Day 2: Environmental Science Review

hey everyone welcome back it's day two of ap daily live for environmental science i'm happy that you've decided to join us again my name is lisa bagley i'm your instructor for this evening and if you didn't have a chance to tune in last night i teach in mesquite isd just outside of dallas west mesquite high school i'm super happy glad to have you with us tonight um shout out to my apes tribe and happy birthday bath so i'm going to go ahead and share my screen and we're going to get started let's talk about what we're going to learn in today's video so in ap daily live video 2 we will answer questions and provide clarification of concepts from video one that's going to happen first we'll conduct a brief overview of the content for this unit which is unit 3 populations we'll discuss general free response question do's and don'ts we'll practice connecting our free response question answers to the science practices to maximize our score potential and finally we'll wrap up with questions and a link to some live practice just a reminder about how to use these videos if you didn't get a chance to watch yesterday's video let me help you uh clue into that so ap daily live videos are designed to help you understand how to demonstrate environmental science content knowledge via the essential science practices that the college board expects you to know we'll talk more about those science practices again tonight these are not specifically content review videos however the ep daily content videos that pertain to the units discussed in each of the review videos will be referenced during the presentation so we're going to talk more about that when we talk about feedback here in just a little bit during the free response model modeling portion of the videos i'll point out common pitfalls that students make when answering exam questions and offer suggestions on how to avoid these in order to maximize scoring potential and as always these videos are best used in conjunction with your own personal review on your own time because you know best what you need to work on i shared these last night but we want to share them again these are helpful links for the ap exam information so um specific information about ap exam dates and times can be found at the following url and you may want to take some screenshots of these as we go through information specifically about our exam ap environmental science can be found at the following url information about the digital exam can be found on the digital testing guide which is at this pdf i'm going to talk a little bit more about digital testing tonight and a preview of the digital exam including how to get your own device ready and the practice app is available at this website so again if you need to take a screenshot that's probably a good idea so let's first jump into questions and clarifications from video one first off thank you my eco warriors about giving me some feedback really really want to say thanks for that because the feedback's very valuable and it can make the videos better so we're going to be those are going to be actionable and i appreciate every little bit of feedback we got so thanks so much for doing that a lot of you all said hey hey we want more content review i can understand that but i want you to understand that the content is out there friends there's a lot of content in ap environmental science and these review videos are short if you want a deep dive into course content specifics i'm encouraging you to watch the ap daily content videos that are available in ap classroom if you go into your ap classroom account they are there for you and they are deep dives into this content that we're talking about they also provide practice exam questions for you both free response and multiple choice check them out please i had questions on how long the kahoot will be available kahoots that are that are presented in these videos are going to be available pretty much indefinitely right now as far as i know um i don't have any plans to take them down and so practice away lots of questions also about real time chat some of you guys remember last year's exams so those questions why aren't you answering questions in the chat real time like last year so um there were some legal and logistic issues with answering um the chat in real time so it was decided that the feedback would be solicited at the end of each video during each video and that's what we did last night we'll continue to do that this is true for every ap course and not just environmental science so if you're tuning in to some of our other video series you will also notice that the feedback is going to be solicited by google form rather than live chat several of you wanted more math and more practice with make a claim type questions wish granted tonight we're going to be practicing some math and we'll be practicing some more make a claim type which is science practice 7 so hang tight let's keep going several of you wanted to know how much of the exam is covered by each unit ask and you shall receive there you go so each there's your units one through nine and how much of the exam content comes from those individual units take a screenshot if you need to so that you know which part is which and you can see there that the first two units are six to eight percent we move into about 10 to 15 percent for units three four five six seven to ten for our pollution units and our biggie with global change at 15 to 20. all right there so there were some questions about specifically what's going on with the digital exam um how how's the college board going to make sure that digital exam takers don't cheat first off not really my wheelhouse but i'm going to tell you this right um some of the things we talked about last night the test questions were designed to be unsearchable via the web and i say that i trust me on that one we worked really hard to make sure that they were not searchable so there it's not going to be an internet search kind of thing there's also some new security features in the app to prevent collaboration and the use of unauthorized aids and finally the test will be reviewed post-exam with anti-plagiarism software and other post-test fraud detection algorithms college board has taken this very very seriously and they want to make sure that there's no um that there's no there's no cheating or there's nothing that that gives digital test takers an advantage um same z same z's paper and digital all right so here's uh here's my next one how should i approach a multiple choice question with a visual stimulus or data given that i have limited time on the exam well here's the deal it's the same way you should approach a question with visual stimulus or data in a free response question i always when i when i talk to kids i always say hey take an overall look at the stimulus that you're given to get a general feel of what's being presented read the title what's shown if it's a graph what's shown on the axes what's shown on the x-axis which don't know the y-axis is there a key that goes along with it what does the prompt tell you that the image is showing or that the visual is showing then once you kind of get an overall picture of what's going on there read the question then go back and find the parts of the stimulus that the question is talking about one of the things that we're modeling here is to read the stimulus and then go back and highlight oh they're talking about shrubs they're talking about demographic transition stage two or whatever just like we practice in this video so the strategies aren't any different because remember you're timed on the free response proportion as well how much do i need to write for an identify prompt not much friends just a complete thought that simply names or identifies the answer to the question so it's an identify meaning just once you identify it that's it when i'm looking at multiple choice questions some of the answers seem very similar how do i make the right choice well first off thanks for saying this because that's on purpose the questions are written so that there are reasonable elements even in your distractor answers meaning the incorrect answers your job is to is to choose the most correct answer remember that the multiple choice portion also tests you via the science practices just like the frq portion so read the question very carefully and answer exactly what it's asking you to do those science practices flow throughout both sections of the exam will the free response have all of the parts like the ones that you modeled last night yep they sure will notice also that although each question has a specific focus like the question your question one will will have elements of design and experiment question two will provide solutions and you'll have to justify those and question three will provide solutions and you'll have to justify with math there are multiple parts and multiple science practices assessed with each question do we have to memorize the science practices nope remember you're not directly tested on the practices but i need to let you know that they are the framework around which every exam question both multiple choice and free response is written understanding how they're used will help you focus in on exactly what's being asked of you especially on free response questions what do we need to include in our experimental design answers well that's going to depend on what the prompt is asking you but i wanted to share with you what science practice for which is scientific experiment experiments specifically ask that you know how to do science practice 4a is identify a testable hypothesis or research question b is identify a research method design or measure used in an investigation c is describe an aspect of a research method design or measure used so we've got two identifies and then a describe 4d is not assessed on the exam it's something that you would do in class it has to do with with experimental design in your classroom and then 4e is explaining modifications to experimental procedures that may alter results we had a little bit of practice with some of those last night we'll have more as we go along through the video series all right shout out to brianna a from california she asked about command verbs on the free response questions yes ma'am we will talk about those you'll get some more specific free response questions and pointers in today's videos but i'll hit the command verbs harder in detail tomorrow like what how much do you need what does this actually mean for you to do all right tomorrow's video we'll have a little preview of all that wonderful stuff help i'm freaking out about the biogeochemical cycles lots of you are freaking out about biogeochem don't freak out my friends take a look at the ap daily videos for topics 1.4 which is the carbon cycle 1.5 which is the nitrogen cycle 1.6 which is phosphorus and 1.7 which is the hydrologic cycle those were done by yours truly and they are in depth now what those don't cover is human impacts because that happens in later but if you want to know the steps and the transformations head there help i'm freaking out about ecosystems ecosystem services what do i need to know about those there's a lot of questions about what's the difference between a regulating surface and a provisioning service ap daily content video topic 2.2 friends head there there's a whole video series three of them on ecosystem services and that's going to give you all you need to know on ecosystem services and how they're used both in the exam and content-wise kyle from fremont california kyle you do not know how iconic fremont is he has a specific question about something i talked about yesterday in the second free response question could gmos be used as a pest control method for free response model 2 part j from yesterday's video excellent excellent question very specific i wanted to address that the answer is no sorry here's why the prompt specifically mentions that the fields in the experiment are sewn with genetically identical alfalfa seeds and the independent variable must be an application of some treatment on top of the constant that the seeds are genetically identical so there's a constant there that the seeds are the same they're genetically identical a plant that is genetically modified to contain genes for pest resistance would introduce an additional variable that is not accounted for in the prompt so gmos would not be a treatment for pesticide i get where you're going it's a great thought and i wanted to address it and finally why are you mean and don't give us guided notes well the primary reason is of course that i'm mean but seriously it's not um note taking my friends is a personal endeavor you should take the notes that you need on the topics that you identify as your weak points this puts you in the driver's seat and in charge of your own learning also i'm a teacher educational research shows that the activity of note taking actually helps you put the stuff you're learning up here sabuya take your notes and by the way i'm just going to say something at the end of this video series there will be some guided notes given to you but not before thanks all right so let's do some content review jumping into populations which is unit 3. generalist species they thrive in changing or disrupted environments an example of a general species would be a raccoon sometimes called a trash panda specialist species are advantaged in environments that are stable however example there would be a real panda pandas are specialists our selected species are physically smaller they have many offspring they have early maturation and sexual maturity they may reproduce only once during their lifetime because their lifetimes are short and they have short life spans k selected species are physically larger they have a few offspring they have late maturation and late sexual maturity they generally generally reproduce more than once during their life lifespan because they have longer lifespans elephants are case selected survivorship curves graphically portray the relative rate of a cohort which is a group of individuals of the same age in a population they look like this we have three types of survivorship curves type 1 type 2 and type 3. type 1 curves show high early survival rates and increasing mortality with age there they are right there type 3 curves show low early survival rates individuals however that do survive or the early part of their lifespans tend to live a full life span and there they are right there it's kind of the inverse type 1 and type 3 are inverse type 2 curves show constant survival rates as the cohort ages and there's that linear that linear line right there in the middle our selected species generally follow type 3 curves and k selected species generally follow type 1 curves population growth will always be limited by resource availability and resources are always finite when resources are abundant population growth increases when resources are scarce unequal distribution in those resources may result in increased mortality events decreased fecundity what the heck is that oh it's the ability to produce new offspring the carrying capacity or k is the measure of the maximum population an ecosystem can support based on resource availability overshoot refers to when a population exceeds the carrying capacity of its ecosystem overshoot can result in environmental consequences such as resource degradation or a die back of the population age structure diagrams are a graphical represent representation of population growth rates they look kind of like this so we often see those in relation to human populations but they can also be created for non-human populations as well these diagrams have characteristic shapes depending on how quickly a population is growing or not growing total fertility rate or tfr refers to the average number of children a woman will have in her lifetime total fertility rate is affected by the age at which a woman has her first child educational opportunities for women access to family planning and government laws policies and laws if the total fertility rate is equal to the replacement level fertility the population is considered stable normally that's around two infant mortality rate refers to the number of deaths prior to age one child mortality would be deaths prior to age five infant mortality is influenced by maternal health care and nutrition guys there's a lot of us on earth there are over 7.8 billion people on the planet human population growth or human population decline in a geographic area is influenced by the birth rate in the area infant mortality rates death rates and access to family planning as well as access to education and age at marriage the earlier you get married the more children you generally reproduce on a global scale human population growth is limited by the earth's carrying capacity and food supply so we're going to talk a little bit about this population growth tends to population group tends to grow exponentially but food supplies tend to grow linearly this is called malthusian theory after thomas malthus and we'll talk a little bit more about that in our practice population growth can be affected by density dependent or density independent factors density dependent factors include access to clean water access to clean air availability of food resources disease transmission territory size density dependent factors are types of factors that affect a population more as the population size increases density independent factors include major storms like hurricanes tornadoes tsunamis etc fires prolonged heat waves and droughts these are factors that affect a population at the same rate no matter what the population size is and you'll notice that there's a little bit of a difference there so these density independent factors tend to be abiotic a population's doubling time can be approximated by the rule of 70. yay math you're going to divide the number 70 by the population's growth percentage the rule of 70 works for a population of any size growing at any rate and you don't need to know the starting population size for instance a population of approximately 374 000 people is growing at a rate of 1.24 yearly how long will it take for the population to double in size 70 divided by 1.24 it's going to double in size in about 56 and a half years or if a population of reindeer doubles in size in 93 years what is the growth rate of the population 70 divided by x equals 93 so that's about a little less than percent growth so about 0.75 percent growth you always want to check this kind of math for reasonableness because if it's growing at one percent then it should double in 70 years so if it's growing higher than one then your doubling time will be less than 70. it's growing if it's doubling in more than 70 than your population then your growth rate should be less than one demographic transition is a country or region's progression from high birth and death rates to lower birth and death rates and from a pre-industrial to an industrial economic system as development and modernization occurs characteristics of developing countries include higher infant mortality rates more children in the workforce lower life expectancy lower rates of access to modern medicine and to education and lower rates of access to safe drinking water and sanitation so we're gonna go just quickly through those stages stage one is your pre-industrial stage birth rates and death rates are high population growth is slow and the population tends to be agrarian or agricultural stage two is our industrializing countries death rates begin to fall but birth rates remain high lifespan begins to increase and population growth is rapid here three of demographic transition is our mature industrial societies birth rates begin to fall death rate remains low from stage two where it dropped and the population growth begins to slow down finally we have stage four or post-industrial our birth and death rates are both low the population is aging when we're talking about age structure diagram we have a higher proportion of aging or elderly individuals total fertility rate may fall below replacement level fertility and population growth is near zero or it might actually be negative we're going to practice with the visual model of those stages in a free response question today let's talk about the science skills that are associated with unit 3. remember of course that any skill can be tested in any unit so for practice one which is concept explanation the college board says that the generals and specialist species and demographic transition can be associated with concept explanation practice five could be data analysis k selected in our selected species survivorship curves carrying capacity age structure diagrams and total fertility rate practice six mathematical routines population growth and resource availability which is the rule of 70. and practice 7 environmental solutions human population dynamics we'll practice with several of these today all right let's talk a little bit about things to do when we write free response questions that are going to be um easier to point and things to do that are that make pointing an frq more difficult for a reader um this is going to help you um get some of those points that you want on your free response questions so as you read your prompt and take it apart for the for the for what the prompt is actually asking you do dive right in to answering that question you do have 23 minutes per question so you need to use your time wisely pace yourself of course 70 minutes three questions about 23 minutes per question so make sure you're planning accordingly remember if you're a digital test taker you can't go backwards and forwards so you need to to keep that in mind for paper exam takers please make sure you write legibly and again for paper exam takers please make sure you organize your responses to the question in the order that it's asked is this essential no does it make it easier to read it does do answer and complete thoughts you don't necessarily have to have complete sentences especially on those shorter prompts which are identified but complete thoughts allow your your reader to know kind of what what you're thinking please elaborate with specific examples where they're asked please show your math units everywhere if there's a calculation show your math everywhere including in the setup and show every math step even if you can do it in your head and a lot of you can you're smart people put it on the paper or put it into your digital testing app with units please check all your calculations for reasonableness that's a biggie when you're asked for a solution to an environmental problem keep in mind the practicality and reasonableness of your solution and what type of solution the question is asking for is it asking for an environmental solution an economic solution a legislative solution a social solution make sure that you read carefully so that you're specifically addressing what they're asking do read and follow the instructions in the question carefully if the prompt asks for two examples of a phenomena only the first two answers that are given will be evaluated regardless of the quality of your additional responses so please make sure that you read if they ask for two give me two if you're asking if they ask for one give one because the additional ones are not evaluated and to do make sure that you're clear on the differences between an environmental effect an economic effect a social effect or a human health effect okay let's talk about some things that it would be better not to do on a free response please don't waste your time on long introductions or background information unless the prompt specifically asks please don't do that don't use absolutes like everything will die or everything will go extinct those are usually not true and they're usually not pointable don't use vague or non-quantifiable terms like that's good for the environment or that's bad for the environment or this hurts human health if it hurts human health be specific as to how or green that's a green solution environmentally friendly or eco these are non-quantifiable terms um they're usually not specific enough to answer what the prompt is actually asking for don't write in first person don't use your name in your response don't use your teacher's name in your response don't use my name in your response and don't ramble get to the point of your response for paper test takers don't use pencil use a ballpoint or non-gel ink pad with blue or black ink will still score you anyway it's just harder to read finally don't panic and don't get upset if you're unfamiliar with a question take a deep breath read it carefully read it calmly think about the practice that you've had here because you probably know something about this topic somewhere in that brain of yours for paper test takers don't scratch out excessively one or two lines through the unwanted text is enough don't leave questions blank there's no penalty for a wrong answer so make every effort on every question and finally don't quit don't quit give it your all let's look at an example all right here we go free response model question one are you ready yes you are boom the consequences of a growing human population have been a concern since the times of thomas malthus oh thomas pelvis when he proposed that humans could exceed their carrying capacity on earth there's thomas malthus and so the concept we're talking about here is carrying capacity describe the concept of a carrying capacity for a species and describe how a change in the availability of a specific resource could affect the carrying capacity of a species this is concept explanation which is practice one so the answer to that first part is just give me what what's the what's the concept of a carrying capacity the carrying capacity is the maximum population size of a given species that an environment can sustain without resource degradation the second one has a little bit more to it so notice that i highlighted a specific resource they're wanting you to say a specific resource in your response and notice that i said if the availability of insert resource here so you could say something like if the availability of water if the availability of food if the availability of habitat but you must name a specific resource because the prompt says specific resource so let's see how we can model answer this if the availability of food water habitat increases then the carrying capacity will also increase or if the availability of choose your resource decreases the carrying capacity will also decrease or if the availability of your chosen resource changes carrying capacity may not be affected but you have to link a specific resource and its availability going up or down to carrying capacity going up or down to get that point right there as the human population grows forests are often clear-cut describe a negative effect of clear cutting forested areas concept explanation by the way so clear cutting is topic 5.2 so if you're not sure about the negative effect of clear cutting check out video 5.2 so trees sequester carbon burning or cutting them releases carbon dioxide which increases climate change trees and forests absorb pollutants so clear cutting them reduces the absorption of pollutants trees hold soil in place so clear-cutting them those clear-cut areas have higher rates of soil erosion and increased chances of flooding trees shade water and soil so clear-cut areas have higher water and soil temperatures which may lead to changes in nutrient cycling in aquatic habitats finally intact forests provide habitat so clear-cutting them will reduce habitat and reduce biodiversity any of these are acceptable negative effects they're all talked about in topic 5.2 besides creating or expanding forest preserves describe one mitigation strategy that humans can employ to reduce the negative impact of human population growth on forests hmm what the heck is a mitigation strategy well mitigation means to reduce the impact or the seriousness of something so mitigation strategy is something that would would tend to reduce the impact right and of course it says reduce the negative impact of human population growth but the word mitigation can be a little bit freaky that's environmental solutions so you're going to provide me with some solutions those solutions um would be in your sustainability which is 5.17 practice sustainable forestry where trees that are harvested can be replaced with seedlings that can grow into new trees include forested areas as part of housing development plans to maintain a portion of land as a forest ecosystem practice sustainable agriculture and food production vertical farming ocean farming to reduce the need to clear forested land for farming manage a forest air forested area to extract some resources while still maintaining the core biomass so the forest can serve an ecological role in the ecosystem ecosystem services build up not out and construct or maintain high density dwellings or neighborhoods that reduce overall land the overall land use for housing developments you don't have to cut down forests for that use alternative fuels rather than burning biomass and finally establish ecotourism in a forested area all right lots of ways you could go there and finally still in part b describe an additional benefit of the mitigation strategy you described in part bii so your additional benefit has to match the mitigation strategy that you chose so as we go through these answers i'm going to say if you chose this then these are acceptable if you chose this these are acceptable so here we go stick with me all right so if you chose practicing sustainable forestry an additional benefit of that is that sustainable foresty preserves biodiversity by maintaining a variety of plant animal species it protects soil and water resources and it provides wooden resources for human use if you chose manage a forested area to do some extraction while still maintaining core biomass oh look at that it preserves biodiversity it protects soil and water resources and it provides wood and resources for human use we're still going on this one all right if you chose include forested areas as part of housing development plans it preserves biodiversity and it protects soil and water resources and it maintains the aesthetic benefit of trees near homes which homeowners like if you chose build up not out and construct high density dwellings then an additional benefit would be preserving biodiversity and protecting soil and water resources as well as reducing the reliance on transportation fueled by fossil fuels which decreases global climate change overall we're still going if you chose to practice sustainable agriculture as your medigap mitigation strategy we will preserve biodiversity and protect soil and water resources if you chose alternative fuels rather than burning biomass it preserves biodiversity and protects soil and water resources it also reduces global climate change and decreases co2 commissions during energy generation when switching from burning biomass to renewable energy resources finally if you chose establishing ecotourism it provides jobs and it brings money to the local economy those would be economic benefits and it doesn't specify in the prompt what kind of benefits it has to be so what did you notice about most of the model answers for the additional benefits of mitigation strategies preserving biodiversity and protecting soil and water resources absolutely as the country industrializes it moves often moves through demographic transition the model below illustrates the changes to the four stages of demographic transition there is the visual of the demographic transition model that we verbally described in the previous slides notice there's the four stages and we've got a key there i'm going to see that again based on the model identify the stage in the demographic transition with the greatest change in crude birth rate so this is a visual representation let's find the crude birth rate there it is and the stage with the greatest decrease or the greatest change it could have been an increase or decrease but in this case it's a decrease is stage two so if we were to take the slope of the line in that area that one's got the greatest slope based on the model describe the relationship between the crude death rate and the crude birth rate that led to the trend in total population in stage two so first off we need to find total population which is your dotted line and when we look at that dotted line there in stage two right the total population is increasing so the crude death rate decreased and the crude birth rate increased and remember well it didn't really increase it remained relatively high which causes the total population to increase rapidly that's what we're seeing there that that stage two is a rapid population increase or population growth rate can be determined by subtracting the death rate from the birth rate so when the birth rate exceeds the death rate then the rate of growth is positive so there'll be population growth could have gone either way with that explain one likely social or economic cause for the change in the crude birth rate as illustrated in stage three so let's first off find the crude birth rate in stage three and there it is so the question is what's the trend that you observe there because there's a change and that's what the question is asking you to to explain so there is a decrease in your crude birth rate this could be caused from a transition from an agricultural country to an industrialized country and that change makes more children a financial burden rather than a financial benefit a rise in relative affluences affluence of the country can affect the status of women there's a decreased reliance on child labor or shift in the social structure expansion of women's status or an access to education to economic opportunity or political power increases the age at which a woman first has her babies and increases career advancement for women which would lead to a reduction in birth rates increased access to contraception which enables family planning and decreases fertility rates the increased average age at marriage if you marry later you tend to have fewer babies which reduces the overall number of children per woman increased access to medical intervention vaccines and prenatal care leads to a decrease in mortality rates and an increase in life expectancy oops any of those would account for that decrease in crude birth rate as shown in stage 3. we're finally at part d during a demographic transition intensive agricultural practices used to feed a growing population can result in soil eroding from crop fields and running off into surface waters make a claim there's your practice 7 that proposes an effective long-term solution to minimize the erosion of topsoil into surface waters so we're going to provide a solution here we go again soil is uh topic 4.2 and um for 5.4 is agriculture so you can maintain and plant vegetated buffers between surface waters and crop fields you could create retention ponds to capture the eroded soil you could maintain cover crops on fields after harvest to to minimize erosion you could use no-till agriculture strip cop cropping contour plowing or terracing any of those would be acceptable long-term solutions to minimize the erosion of topsoil now justify your claim justify the claim that you made in the in the previous section di by explaining an additional benefit to the proposed solution other than just preventing the erosion of topsoil all right here we go additional benefit justify it this is again practice seven all right so an additional benefit other than preventing the erosion of topsoil if you chose planting vegetated buffers it creates habitat to maintain biodiversity creates habitat for crop pest predators which provides a natural method of pest control and these vegetated buffers filter additional pollutants from runoff it also recharges groundwater by slowing the flow of runoff which allows for infiltration if you chose creating retention ponds this would create a habitat for aquatic species which helps maintain biodiversity filters additional pollutants from runoff and recharges groundwater by slowing the flow of runoff and allowing for infiltration if you chose maintaining cover crops on your field that provides nutrients for your next crop so we're talking a lot about agriculture here it suppresses weeds and it filters additional pollutants from runoff if you chose using no-till agriculture that reduces fuel requirements needed on your farm it also reduces the release of greenhouse gases associated with mechanized agriculture which decreases global climate change if you chose using strip cop cropping contour plowing or terracing these improve crop yields they maintain soil fertility and they reduce fertilizer runoff into waterways oh and they also it also allows for the cultivation of crops on steep slopes so all of this is practice seven practice seven is heavily tested on the frq portion of the exam both questions two and three will ask you to provide environmental solutions and to justify them you'll see this again in model question two all right deep breath these are long all right here we go birth rates infant mortality rates death rates and a variety of other factors affect whether the size of a human population is growing or declining demographic changes have important environmental social and economic implications identify one factor that contributes to the high crude death rate in countries that have never experienced the changes that result from a demographic transition okay this is practice one and a lot of this actually kind of links in with the previous one as well so unsafe drinking water or a lack of access to clean water a loss of agricultural land for crops and livestock stock a lack of access to health care risk of death during pregnancy or lack of quality health care high rates of diseases such as heart disease respiratory infections infectious diseases like hiv aids malaria tuberculosis high infant mortality so those are those and those that's an identified prompt so you just need to tell tell me what it is and move on describe a typical age structure diagram for a developing country a developing country has a pyramid-shaped age structure diagram there's more individuals in the younger cohorts and there's a broad base to that pyramid they look kind of like the one that i just popped up on the screen a rapidly growing population will have more individuals in the younger cohorts and the pre-reproductive pre-reproductive stages and less than the older cohorts any of these could um these these points any of these would be acceptable answers or a rapidly growing population will have a higher proportion of younger people than will a stable or declining population but you need to describe it for me all right so demographic data from 2018 are shown in the table below use the data in the table to answer the following questions my animation was a little off there that's this is obviously practice six with which is mathematical routines so we've got world more developed countries less developed countries we have population in millions crude birth rate per 1000 crude death rate per 1000. so again i like to take a visual of what i'm looking at so we're going to calculate the percent of the global population that was living in more developed countries in 2018 okay so the way to do this this is our formula so it's the number of people in the more developed countries and our denominator our divisor is the number of people total in the world and then times 100. so first find your your more developed countries number there she blows then your world number there it is so when we plug those numbers in to our formula this is what we got approximately 16.6 okay we're going to use the data to answer the following questions we're going to calculate the population growth rate as a percent for less developed countries and we're going to show our work again this is mathematical routines there's our less developed countries and we want our crude birth rate so we have 21 births per thousand people minus seven deaths per thousand people times 100 and when when we actually we're going to reduce that so we've got 21 births minus 7 deaths divided by 10 equals 14 over 10 which equals 1.4 percent as countries change during demographic transition there's often a growing demand for meat in human diets it takes an estimated one thousand five seven hundred one thousand seven hundred fifty liters of water to produce about 113 grams beef the average person in a more developed country consumes about 85 grams of beef per day so we've got some important numbers in there calculate the amount of water needed in liters per year to produce the beef consumed by one person in a more developed country and of course show your work here we go this is topic 5.7 by the way 85 grams per one day times 365 days in a year times the liters of water per grams of beef yields 4.8 times 10 to the fifth liters of water per year dimensional analysis same prompt different question make a claim to produ to propose a solution that would reduce the amount of water required to produce enough food for individuals make a claim we're going to reduce the amount of water environmental solutions here we go there's a lot of them eat less meat produce plant-based protein sources use drip irrigation for crops plant local or native crops that do not require as much water plant gmo crops that do not require as much water switch from water intensive livestock farming like beef to less water intensive livestock farming like chicken switch from feedlots or kafos which can lead to soil compactation and runoff to more sustainable farming methods any of those would reduce the amount of water required to produce enough food for individuals same prompt different question describe one environmental disadvantage associated with increasing amount of meat in human diets other than the con associated with the consumption of water which we just talked about again environmental solutions more land is required to produce the same number of calories from meat as from plants the use of animal feedlots to raise animals generates large amounts of waste this contaminates ground in surface waters animal feedlots increases incidence of disease in livestock has an unpleasant odor and increases water pollution overgrazing can occur because we have too many animals in one area and cattle release greenhouse gases such as methane which can exacerbate global climate change sorry about that guys i had a leftover from the previous one so we've got our over grazing which is on both those slides there and then cattle releasing greenhouse gases such as methane so there's there's one two three four five of them including that methane whoops all right so what should we take away from today things to remember remembering a few key do's and don'ts for your free response questions can increase your scoring potential in order to earn full credit you must show all your math work as well as the units in each step of your calculations it's going to be really really good to get familiar with science practice 7 which is environmental solutions and how to justify your answers there be sure to reference a stimulus image graph or table if you're asked to provide evidence and you have a graphical stimulus and of course careful reading of the prompts for context clues will give you a big advantage when it comes to earning points so once again i am soliciting your help with clarification and information what can i do to make things clearer and better there's your google feedback form there's your qr code lay it on me and give you a second to grab that of course i'm going to answer some selected submitted questions you might get a shout out at the beginning of ap daily live video 3. be sure to tune in to us preview of that video we'll go with clarifications and answers to submitted questions for ap daily live video 2 just like we did today content review on earth systems lots of visual models in this one of course frq modeling with connecting science practices to content knowledge interactive practice on concepts in video three here's your kahoot tell us what you got there's your kahoot url your game pin and your qr code gamepin is zero zero five seven eight two seven nine five i loved seeing everybody play yesterday have at it friends as always thanks for watching and i'll see you tomorrow night you

hey everyone welcome back it&#39;s day two of ap daily live for environmental science i&#39;m happy that you&#39;ve decided to join us again my name is lisa bagley i&#39;m your instructor for this evening and if you didn&#39;t have a chance to tune in last night i teach in mesquite isd just outside of dallas west mesquite high school i&#39;m super happy glad to have you with us tonight um shout out to my apes tribe and happy birthday bath so i&#39;m going to go ahead and share my screen and we&#39;re going to get started let&#39;s talk about what we&#39;re going to learn in today&#39;s video so in ap daily live video 2 we will answer questions and provide clarification of concepts from video one that&#39;s going to happen first we&#39;ll conduct a brief overview of the content for this unit which is unit 3 populations we&#39;ll discuss general free response question do&#39;s and don&#39;ts we&#39;ll practice connecting our free response question answers to the science practices to maximize our score potential and finally we&#39;ll wrap up with questions and a link to some live practice just a reminder about how to use these videos if you didn&#39;t get a chance to watch yesterday&#39;s video let me help you uh clue into that so ap daily live videos are designed to help you understand how to demonstrate environmental science content knowledge via the essential science practices that the college board expects you to know we&#39;ll talk more about those science practices again tonight these are not specifically content review videos however the ep daily content videos that pertain to the units discussed in each of the review videos will be referenced during the presentation so we&#39;re going to talk more about that when we talk about feedback here in just a little bit during the free response model modeling portion of the videos i&#39;ll point out common pitfalls that students make when answering exam questions and offer suggestions on how to avoid these in order to maximize scoring potential and as always these videos are best used in conjunction with your own personal review on your own time because you know best what you need to work on i shared these last night but we want to share them again these are helpful links for the ap exam information so um specific information about ap exam dates and times can be found at the following url and you may want to take some screenshots of these as we go through information specifically about our exam ap environmental science can be found at the following url information about the digital exam can be found on the digital testing guide which is at this pdf i&#39;m going to talk a little bit more about digital testing tonight and a preview of the digital exam including how to get your own device ready and the practice app is available at this website so again if you need to take a screenshot that&#39;s probably a good idea so let&#39;s first jump into questions and clarifications from video one first off thank you my eco warriors about giving me some feedback really really want to say thanks for that because the feedback&#39;s very valuable and it can make the videos better so we&#39;re going to be those are going to be actionable and i appreciate every little bit of feedback we got so thanks so much for doing that a lot of you all said hey hey we want more content review i can understand that but i want you to understand that the content is out there friends there&#39;s a lot of content in ap environmental science and these review videos are short if you want a deep dive into course content specifics i&#39;m encouraging you to watch the ap daily content videos that are available in ap classroom if you go into your ap classroom account they are there for you and they are deep dives into this content that we&#39;re talking about they also provide practice exam questions for you both free response and multiple choice check them out please i had questions on how long the kahoot will be available kahoots that are that are presented in these videos are going to be available pretty much indefinitely right now as far as i know um i don&#39;t have any plans to take them down and so practice away lots of questions also about real time chat some of you guys remember last year&#39;s exams so those questions why aren&#39;t you answering questions in the chat real time like last year so um there were some legal and logistic issues with answering um the chat in real time so it was decided that the feedback would be solicited at the end of each video during each video and that&#39;s what we did last night we&#39;ll continue to do that this is true for every ap course and not just environmental science so if you&#39;re tuning in to some of our other video series you will also notice that the feedback is going to be solicited by google form rather than live chat several of you wanted more math and more practice with make a claim type questions wish granted tonight we&#39;re going to be practicing some math and we&#39;ll be practicing some more make a claim type which is science practice 7 so hang tight let&#39;s keep going several of you wanted to know how much of the exam is covered by each unit ask and you shall receive there you go so each there&#39;s your units one through nine and how much of the exam content comes from those individual units take a screenshot if you need to so that you know which part is which and you can see there that the first two units are six to eight percent we move into about 10 to 15 percent for units three four five six seven to ten for our pollution units and our biggie with global change at 15 to 20. all right there so there were some questions about specifically what&#39;s going on with the digital exam um how how&#39;s the college board going to make sure that digital exam takers don&#39;t cheat first off not really my wheelhouse but i&#39;m going to tell you this right um some of the things we talked about last night the test questions were designed to be unsearchable via the web and i say that i trust me on that one we worked really hard to make sure that they were not searchable so there it&#39;s not going to be an internet search kind of thing there&#39;s also some new security features in the app to prevent collaboration and the use of unauthorized aids and finally the test will be reviewed post-exam with anti-plagiarism software and other post-test fraud detection algorithms college board has taken this very very seriously and they want to make sure that there&#39;s no um that there&#39;s no there&#39;s no cheating or there&#39;s nothing that that gives digital test takers an advantage um same z same z&#39;s paper and digital all right so here&#39;s uh here&#39;s my next one how should i approach a multiple choice question with a visual stimulus or data given that i have limited time on the exam well here&#39;s the deal it&#39;s the same way you should approach a question with visual stimulus or data in a free response question i always when i when i talk to kids i always say hey take an overall look at the stimulus that you&#39;re given to get a general feel of what&#39;s being presented read the title what&#39;s shown if it&#39;s a graph what&#39;s shown on the axes what&#39;s shown on the x-axis which don&#39;t know the y-axis is there a key that goes along with it what does the prompt tell you that the image is showing or that the visual is showing then once you kind of get an overall picture of what&#39;s going on there read the question then go back and find the parts of the stimulus that the question is talking about one of the things that we&#39;re modeling here is to read the stimulus and then go back and highlight oh they&#39;re talking about shrubs they&#39;re talking about demographic transition stage two or whatever just like we practice in this video so the strategies aren&#39;t any different because remember you&#39;re timed on the free response proportion as well how much do i need to write for an identify prompt not much friends just a complete thought that simply names or identifies the answer to the question so it&#39;s an identify meaning just once you identify it that&#39;s it when i&#39;m looking at multiple choice questions some of the answers seem very similar how do i make the right choice well first off thanks for saying this because that&#39;s on purpose the questions are written so that there are reasonable elements even in your distractor answers meaning the incorrect answers your job is to is to choose the most correct answer remember that the multiple choice portion also tests you via the science practices just like the frq portion so read the question very carefully and answer exactly what it&#39;s asking you to do those science practices flow throughout both sections of the exam will the free response have all of the parts like the ones that you modeled last night yep they sure will notice also that although each question has a specific focus like the question your question one will will have elements of design and experiment question two will provide solutions and you&#39;ll have to justify those and question three will provide solutions and you&#39;ll have to justify with math there are multiple parts and multiple science practices assessed with each question do we have to memorize the science practices nope remember you&#39;re not directly tested on the practices but i need to let you know that they are the framework around which every exam question both multiple choice and free response is written understanding how they&#39;re used will help you focus in on exactly what&#39;s being asked of you especially on free response questions what do we need to include in our experimental design answers well that&#39;s going to depend on what the prompt is asking you but i wanted to share with you what science practice for which is scientific experiment experiments specifically ask that you know how to do science practice 4a is identify a testable hypothesis or research question b is identify a research method design or measure used in an investigation c is describe an aspect of a research method design or measure used so we&#39;ve got two identifies and then a describe 4d is not assessed on the exam it&#39;s something that you would do in class it has to do with with experimental design in your classroom and then 4e is explaining modifications to experimental procedures that may alter results we had a little bit of practice with some of those last night we&#39;ll have more as we go along through the video series all right shout out to brianna a from california she asked about command verbs on the free response questions yes ma&#39;am we will talk about those you&#39;ll get some more specific free response questions and pointers in today&#39;s videos but i&#39;ll hit the command verbs harder in detail tomorrow like what how much do you need what does this actually mean for you to do all right tomorrow&#39;s video we&#39;ll have a little preview of all that wonderful stuff help i&#39;m freaking out about the biogeochemical cycles lots of you are freaking out about biogeochem don&#39;t freak out my friends take a look at the ap daily videos for topics 1.4 which is the carbon cycle 1.5 which is the nitrogen cycle 1.6 which is phosphorus and 1.7 which is the hydrologic cycle those were done by yours truly and they are in depth now what those don&#39;t cover is human impacts because that happens in later but if you want to know the steps and the transformations head there help i&#39;m freaking out about ecosystems ecosystem services what do i need to know about those there&#39;s a lot of questions about what&#39;s the difference between a regulating surface and a provisioning service ap daily content video topic 2.2 friends head there there&#39;s a whole video series three of them on ecosystem services and that&#39;s going to give you all you need to know on ecosystem services and how they&#39;re used both in the exam and content-wise kyle from fremont california kyle you do not know how iconic fremont is he has a specific question about something i talked about yesterday in the second free response question could gmos be used as a pest control method for free response model 2 part j from yesterday&#39;s video excellent excellent question very specific i wanted to address that the answer is no sorry here&#39;s why the prompt specifically mentions that the fields in the experiment are sewn with genetically identical alfalfa seeds and the independent variable must be an application of some treatment on top of the constant that the seeds are genetically identical so there&#39;s a constant there that the seeds are the same they&#39;re genetically identical a plant that is genetically modified to contain genes for pest resistance would introduce an additional variable that is not accounted for in the prompt so gmos would not be a treatment for pesticide i get where you&#39;re going it&#39;s a great thought and i wanted to address it and finally why are you mean and don&#39;t give us guided notes well the primary reason is of course that i&#39;m mean but seriously it&#39;s not um note taking my friends is a personal endeavor you should take the notes that you need on the topics that you identify as your weak points this puts you in the driver&#39;s seat and in charge of your own learning also i&#39;m a teacher educational research shows that the activity of note taking actually helps you put the stuff you&#39;re learning up here sabuya take your notes and by the way i&#39;m just going to say something at the end of this video series there will be some guided notes given to you but not before thanks all right so let&#39;s do some content review jumping into populations which is unit 3. generalist species they thrive in changing or disrupted environments an example of a general species would be a raccoon sometimes called a trash panda specialist species are advantaged in environments that are stable however example there would be a real panda pandas are specialists our selected species are physically smaller they have many offspring they have early maturation and sexual maturity they may reproduce only once during their lifetime because their lifetimes are short and they have short life spans k selected species are physically larger they have a few offspring they have late maturation and late sexual maturity they generally generally reproduce more than once during their life lifespan because they have longer lifespans elephants are case selected survivorship curves graphically portray the relative rate of a cohort which is a group of individuals of the same age in a population they look like this we have three types of survivorship curves type 1 type 2 and type 3. type 1 curves show high early survival rates and increasing mortality with age there they are right there type 3 curves show low early survival rates individuals however that do survive or the early part of their lifespans tend to live a full life span and there they are right there it&#39;s kind of the inverse type 1 and type 3 are inverse type 2 curves show constant survival rates as the cohort ages and there&#39;s that linear that linear line right there in the middle our selected species generally follow type 3 curves and k selected species generally follow type 1 curves population growth will always be limited by resource availability and resources are always finite when resources are abundant population growth increases when resources are scarce unequal distribution in those resources may result in increased mortality events decreased fecundity what the heck is that oh it&#39;s the ability to produce new offspring the carrying capacity or k is the measure of the maximum population an ecosystem can support based on resource availability overshoot refers to when a population exceeds the carrying capacity of its ecosystem overshoot can result in environmental consequences such as resource degradation or a die back of the population age structure diagrams are a graphical represent representation of population growth rates they look kind of like this so we often see those in relation to human populations but they can also be created for non-human populations as well these diagrams have characteristic shapes depending on how quickly a population is growing or not growing total fertility rate or tfr refers to the average number of children a woman will have in her lifetime total fertility rate is affected by the age at which a woman has her first child educational opportunities for women access to family planning and government laws policies and laws if the total fertility rate is equal to the replacement level fertility the population is considered stable normally that&#39;s around two infant mortality rate refers to the number of deaths prior to age one child mortality would be deaths prior to age five infant mortality is influenced by maternal health care and nutrition guys there&#39;s a lot of us on earth there are over 7.8 billion people on the planet human population growth or human population decline in a geographic area is influenced by the birth rate in the area infant mortality rates death rates and access to family planning as well as access to education and age at marriage the earlier you get married the more children you generally reproduce on a global scale human population growth is limited by the earth&#39;s carrying capacity and food supply so we&#39;re going to talk a little bit about this population growth tends to population group tends to grow exponentially but food supplies tend to grow linearly this is called malthusian theory after thomas malthus and we&#39;ll talk a little bit more about that in our practice population growth can be affected by density dependent or density independent factors density dependent factors include access to clean water access to clean air availability of food resources disease transmission territory size density dependent factors are types of factors that affect a population more as the population size increases density independent factors include major storms like hurricanes tornadoes tsunamis etc fires prolonged heat waves and droughts these are factors that affect a population at the same rate no matter what the population size is and you&#39;ll notice that there&#39;s a little bit of a difference there so these density independent factors tend to be abiotic a population&#39;s doubling time can be approximated by the rule of 70. yay math you&#39;re going to divide the number 70 by the population&#39;s growth percentage the rule of 70 works for a population of any size growing at any rate and you don&#39;t need to know the starting population size for instance a population of approximately 374 000 people is growing at a rate of 1.24 yearly how long will it take for the population to double in size 70 divided by 1.24 it&#39;s going to double in size in about 56 and a half years or if a population of reindeer doubles in size in 93 years what is the growth rate of the population 70 divided by x equals 93 so that&#39;s about a little less than percent growth so about 0.75 percent growth you always want to check this kind of math for reasonableness because if it&#39;s growing at one percent then it should double in 70 years so if it&#39;s growing higher than one then your doubling time will be less than 70. it&#39;s growing if it&#39;s doubling in more than 70 than your population then your growth rate should be less than one demographic transition is a country or region&#39;s progression from high birth and death rates to lower birth and death rates and from a pre-industrial to an industrial economic system as development and modernization occurs characteristics of developing countries include higher infant mortality rates more children in the workforce lower life expectancy lower rates of access to modern medicine and to education and lower rates of access to safe drinking water and sanitation so we&#39;re gonna go just quickly through those stages stage one is your pre-industrial stage birth rates and death rates are high population growth is slow and the population tends to be agrarian or agricultural stage two is our industrializing countries death rates begin to fall but birth rates remain high lifespan begins to increase and population growth is rapid here three of demographic transition is our mature industrial societies birth rates begin to fall death rate remains low from stage two where it dropped and the population growth begins to slow down finally we have stage four or post-industrial our birth and death rates are both low the population is aging when we&#39;re talking about age structure diagram we have a higher proportion of aging or elderly individuals total fertility rate may fall below replacement level fertility and population growth is near zero or it might actually be negative we&#39;re going to practice with the visual model of those stages in a free response question today let&#39;s talk about the science skills that are associated with unit 3. remember of course that any skill can be tested in any unit so for practice one which is concept explanation the college board says that the generals and specialist species and demographic transition can be associated with concept explanation practice five could be data analysis k selected in our selected species survivorship curves carrying capacity age structure diagrams and total fertility rate practice six mathematical routines population growth and resource availability which is the rule of 70. and practice 7 environmental solutions human population dynamics we&#39;ll practice with several of these today all right let&#39;s talk a little bit about things to do when we write free response questions that are going to be um easier to point and things to do that are that make pointing an frq more difficult for a reader um this is going to help you um get some of those points that you want on your free response questions so as you read your prompt and take it apart for the for the for what the prompt is actually asking you do dive right in to answering that question you do have 23 minutes per question so you need to use your time wisely pace yourself of course 70 minutes three questions about 23 minutes per question so make sure you&#39;re planning accordingly remember if you&#39;re a digital test taker you can&#39;t go backwards and forwards so you need to to keep that in mind for paper exam takers please make sure you write legibly and again for paper exam takers please make sure you organize your responses to the question in the order that it&#39;s asked is this essential no does it make it easier to read it does do answer and complete thoughts you don&#39;t necessarily have to have complete sentences especially on those shorter prompts which are identified but complete thoughts allow your your reader to know kind of what what you&#39;re thinking please elaborate with specific examples where they&#39;re asked please show your math units everywhere if there&#39;s a calculation show your math everywhere including in the setup and show every math step even if you can do it in your head and a lot of you can you&#39;re smart people put it on the paper or put it into your digital testing app with units please check all your calculations for reasonableness that&#39;s a biggie when you&#39;re asked for a solution to an environmental problem keep in mind the practicality and reasonableness of your solution and what type of solution the question is asking for is it asking for an environmental solution an economic solution a legislative solution a social solution make sure that you read carefully so that you&#39;re specifically addressing what they&#39;re asking do read and follow the instructions in the question carefully if the prompt asks for two examples of a phenomena only the first two answers that are given will be evaluated regardless of the quality of your additional responses so please make sure that you read if they ask for two give me two if you&#39;re asking if they ask for one give one because the additional ones are not evaluated and to do make sure that you&#39;re clear on the differences between an environmental effect an economic effect a social effect or a human health effect okay let&#39;s talk about some things that it would be better not to do on a free response please don&#39;t waste your time on long introductions or background information unless the prompt specifically asks please don&#39;t do that don&#39;t use absolutes like everything will die or everything will go extinct those are usually not true and they&#39;re usually not pointable don&#39;t use vague or non-quantifiable terms like that&#39;s good for the environment or that&#39;s bad for the environment or this hurts human health if it hurts human health be specific as to how or green that&#39;s a green solution environmentally friendly or eco these are non-quantifiable terms um they&#39;re usually not specific enough to answer what the prompt is actually asking for don&#39;t write in first person don&#39;t use your name in your response don&#39;t use your teacher&#39;s name in your response don&#39;t use my name in your response and don&#39;t ramble get to the point of your response for paper test takers don&#39;t use pencil use a ballpoint or non-gel ink pad with blue or black ink will still score you anyway it&#39;s just harder to read finally don&#39;t panic and don&#39;t get upset if you&#39;re unfamiliar with a question take a deep breath read it carefully read it calmly think about the practice that you&#39;ve had here because you probably know something about this topic somewhere in that brain of yours for paper test takers don&#39;t scratch out excessively one or two lines through the unwanted text is enough don&#39;t leave questions blank there&#39;s no penalty for a wrong answer so make every effort on every question and finally don&#39;t quit don&#39;t quit give it your all let&#39;s look at an example all right here we go free response model question one are you ready yes you are boom the consequences of a growing human population have been a concern since the times of thomas malthus oh thomas pelvis when he proposed that humans could exceed their carrying capacity on earth there&#39;s thomas malthus and so the concept we&#39;re talking about here is carrying capacity describe the concept of a carrying capacity for a species and describe how a change in the availability of a specific resource could affect the carrying capacity of a species this is concept explanation which is practice one so the answer to that first part is just give me what what&#39;s the what&#39;s the concept of a carrying capacity the carrying capacity is the maximum population size of a given species that an environment can sustain without resource degradation the second one has a little bit more to it so notice that i highlighted a specific resource they&#39;re wanting you to say a specific resource in your response and notice that i said if the availability of insert resource here so you could say something like if the availability of water if the availability of food if the availability of habitat but you must name a specific resource because the prompt says specific resource so let&#39;s see how we can model answer this if the availability of food water habitat increases then the carrying capacity will also increase or if the availability of choose your resource decreases the carrying capacity will also decrease or if the availability of your chosen resource changes carrying capacity may not be affected but you have to link a specific resource and its availability going up or down to carrying capacity going up or down to get that point right there as the human population grows forests are often clear-cut describe a negative effect of clear cutting forested areas concept explanation by the way so clear cutting is topic 5.2 so if you&#39;re not sure about the negative effect of clear cutting check out video 5.2 so trees sequester carbon burning or cutting them releases carbon dioxide which increases climate change trees and forests absorb pollutants so clear cutting them reduces the absorption of pollutants trees hold soil in place so clear-cutting them those clear-cut areas have higher rates of soil erosion and increased chances of flooding trees shade water and soil so clear-cut areas have higher water and soil temperatures which may lead to changes in nutrient cycling in aquatic habitats finally intact forests provide habitat so clear-cutting them will reduce habitat and reduce biodiversity any of these are acceptable negative effects they&#39;re all talked about in topic 5.2 besides creating or expanding forest preserves describe one mitigation strategy that humans can employ to reduce the negative impact of human population growth on forests hmm what the heck is a mitigation strategy well mitigation means to reduce the impact or the seriousness of something so mitigation strategy is something that would would tend to reduce the impact right and of course it says reduce the negative impact of human population growth but the word mitigation can be a little bit freaky that&#39;s environmental solutions so you&#39;re going to provide me with some solutions those solutions um would be in your sustainability which is 5.17 practice sustainable forestry where trees that are harvested can be replaced with seedlings that can grow into new trees include forested areas as part of housing development plans to maintain a portion of land as a forest ecosystem practice sustainable agriculture and food production vertical farming ocean farming to reduce the need to clear forested land for farming manage a forest air forested area to extract some resources while still maintaining the core biomass so the forest can serve an ecological role in the ecosystem ecosystem services build up not out and construct or maintain high density dwellings or neighborhoods that reduce overall land the overall land use for housing developments you don&#39;t have to cut down forests for that use alternative fuels rather than burning biomass and finally establish ecotourism in a forested area all right lots of ways you could go there and finally still in part b describe an additional benefit of the mitigation strategy you described in part bii so your additional benefit has to match the mitigation strategy that you chose so as we go through these answers i&#39;m going to say if you chose this then these are acceptable if you chose this these are acceptable so here we go stick with me all right so if you chose practicing sustainable forestry an additional benefit of that is that sustainable foresty preserves biodiversity by maintaining a variety of plant animal species it protects soil and water resources and it provides wooden resources for human use if you chose manage a forested area to do some extraction while still maintaining core biomass oh look at that it preserves biodiversity it protects soil and water resources and it provides wood and resources for human use we&#39;re still going on this one all right if you chose include forested areas as part of housing development plans it preserves biodiversity and it protects soil and water resources and it maintains the aesthetic benefit of trees near homes which homeowners like if you chose build up not out and construct high density dwellings then an additional benefit would be preserving biodiversity and protecting soil and water resources as well as reducing the reliance on transportation fueled by fossil fuels which decreases global climate change overall we&#39;re still going if you chose to practice sustainable agriculture as your medigap mitigation strategy we will preserve biodiversity and protect soil and water resources if you chose alternative fuels rather than burning biomass it preserves biodiversity and protects soil and water resources it also reduces global climate change and decreases co2 commissions during energy generation when switching from burning biomass to renewable energy resources finally if you chose establishing ecotourism it provides jobs and it brings money to the local economy those would be economic benefits and it doesn&#39;t specify in the prompt what kind of benefits it has to be so what did you notice about most of the model answers for the additional benefits of mitigation strategies preserving biodiversity and protecting soil and water resources absolutely as the country industrializes it moves often moves through demographic transition the model below illustrates the changes to the four stages of demographic transition there is the visual of the demographic transition model that we verbally described in the previous slides notice there&#39;s the four stages and we&#39;ve got a key there i&#39;m going to see that again based on the model identify the stage in the demographic transition with the greatest change in crude birth rate so this is a visual representation let&#39;s find the crude birth rate there it is and the stage with the greatest decrease or the greatest change it could have been an increase or decrease but in this case it&#39;s a decrease is stage two so if we were to take the slope of the line in that area that one&#39;s got the greatest slope based on the model describe the relationship between the crude death rate and the crude birth rate that led to the trend in total population in stage two so first off we need to find total population which is your dotted line and when we look at that dotted line there in stage two right the total population is increasing so the crude death rate decreased and the crude birth rate increased and remember well it didn&#39;t really increase it remained relatively high which causes the total population to increase rapidly that&#39;s what we&#39;re seeing there that that stage two is a rapid population increase or population growth rate can be determined by subtracting the death rate from the birth rate so when the birth rate exceeds the death rate then the rate of growth is positive so there&#39;ll be population growth could have gone either way with that explain one likely social or economic cause for the change in the crude birth rate as illustrated in stage three so let&#39;s first off find the crude birth rate in stage three and there it is so the question is what&#39;s the trend that you observe there because there&#39;s a change and that&#39;s what the question is asking you to to explain so there is a decrease in your crude birth rate this could be caused from a transition from an agricultural country to an industrialized country and that change makes more children a financial burden rather than a financial benefit a rise in relative affluences affluence of the country can affect the status of women there&#39;s a decreased reliance on child labor or shift in the social structure expansion of women&#39;s status or an access to education to economic opportunity or political power increases the age at which a woman first has her babies and increases career advancement for women which would lead to a reduction in birth rates increased access to contraception which enables family planning and decreases fertility rates the increased average age at marriage if you marry later you tend to have fewer babies which reduces the overall number of children per woman increased access to medical intervention vaccines and prenatal care leads to a decrease in mortality rates and an increase in life expectancy oops any of those would account for that decrease in crude birth rate as shown in stage 3. we&#39;re finally at part d during a demographic transition intensive agricultural practices used to feed a growing population can result in soil eroding from crop fields and running off into surface waters make a claim there&#39;s your practice 7 that proposes an effective long-term solution to minimize the erosion of topsoil into surface waters so we&#39;re going to provide a solution here we go again soil is uh topic 4.2 and um for 5.4 is agriculture so you can maintain and plant vegetated buffers between surface waters and crop fields you could create retention ponds to capture the eroded soil you could maintain cover crops on fields after harvest to to minimize erosion you could use no-till agriculture strip cop cropping contour plowing or terracing any of those would be acceptable long-term solutions to minimize the erosion of topsoil now justify your claim justify the claim that you made in the in the previous section di by explaining an additional benefit to the proposed solution other than just preventing the erosion of topsoil all right here we go additional benefit justify it this is again practice seven all right so an additional benefit other than preventing the erosion of topsoil if you chose planting vegetated buffers it creates habitat to maintain biodiversity creates habitat for crop pest predators which provides a natural method of pest control and these vegetated buffers filter additional pollutants from runoff it also recharges groundwater by slowing the flow of runoff which allows for infiltration if you chose creating retention ponds this would create a habitat for aquatic species which helps maintain biodiversity filters additional pollutants from runoff and recharges groundwater by slowing the flow of runoff and allowing for infiltration if you chose maintaining cover crops on your field that provides nutrients for your next crop so we&#39;re talking a lot about agriculture here it suppresses weeds and it filters additional pollutants from runoff if you chose using no-till agriculture that reduces fuel requirements needed on your farm it also reduces the release of greenhouse gases associated with mechanized agriculture which decreases global climate change if you chose using strip cop cropping contour plowing or terracing these improve crop yields they maintain soil fertility and they reduce fertilizer runoff into waterways oh and they also it also allows for the cultivation of crops on steep slopes so all of this is practice seven practice seven is heavily tested on the frq portion of the exam both questions two and three will ask you to provide environmental solutions and to justify them you&#39;ll see this again in model question two all right deep breath these are long all right here we go birth rates infant mortality rates death rates and a variety of other factors affect whether the size of a human population is growing or declining demographic changes have important environmental social and economic implications identify one factor that contributes to the high crude death rate in countries that have never experienced the changes that result from a demographic transition okay this is practice one and a lot of this actually kind of links in with the previous one as well so unsafe drinking water or a lack of access to clean water a loss of agricultural land for crops and livestock stock a lack of access to health care risk of death during pregnancy or lack of quality health care high rates of diseases such as heart disease respiratory infections infectious diseases like hiv aids malaria tuberculosis high infant mortality so those are those and those that&#39;s an identified prompt so you just need to tell tell me what it is and move on describe a typical age structure diagram for a developing country a developing country has a pyramid-shaped age structure diagram there&#39;s more individuals in the younger cohorts and there&#39;s a broad base to that pyramid they look kind of like the one that i just popped up on the screen a rapidly growing population will have more individuals in the younger cohorts and the pre-reproductive pre-reproductive stages and less than the older cohorts any of these could um these these points any of these would be acceptable answers or a rapidly growing population will have a higher proportion of younger people than will a stable or declining population but you need to describe it for me all right so demographic data from 2018 are shown in the table below use the data in the table to answer the following questions my animation was a little off there that&#39;s this is obviously practice six with which is mathematical routines so we&#39;ve got world more developed countries less developed countries we have population in millions crude birth rate per 1000 crude death rate per 1000. so again i like to take a visual of what i&#39;m looking at so we&#39;re going to calculate the percent of the global population that was living in more developed countries in 2018 okay so the way to do this this is our formula so it&#39;s the number of people in the more developed countries and our denominator our divisor is the number of people total in the world and then times 100. so first find your your more developed countries number there she blows then your world number there it is so when we plug those numbers in to our formula this is what we got approximately 16.6 okay we&#39;re going to use the data to answer the following questions we&#39;re going to calculate the population growth rate as a percent for less developed countries and we&#39;re going to show our work again this is mathematical routines there&#39;s our less developed countries and we want our crude birth rate so we have 21 births per thousand people minus seven deaths per thousand people times 100 and when when we actually we&#39;re going to reduce that so we&#39;ve got 21 births minus 7 deaths divided by 10 equals 14 over 10 which equals 1.4 percent as countries change during demographic transition there&#39;s often a growing demand for meat in human diets it takes an estimated one thousand five seven hundred one thousand seven hundred fifty liters of water to produce about 113 grams beef the average person in a more developed country consumes about 85 grams of beef per day so we&#39;ve got some important numbers in there calculate the amount of water needed in liters per year to produce the beef consumed by one person in a more developed country and of course show your work here we go this is topic 5.7 by the way 85 grams per one day times 365 days in a year times the liters of water per grams of beef yields 4.8 times 10 to the fifth liters of water per year dimensional analysis same prompt different question make a claim to produ to propose a solution that would reduce the amount of water required to produce enough food for individuals make a claim we&#39;re going to reduce the amount of water environmental solutions here we go there&#39;s a lot of them eat less meat produce plant-based protein sources use drip irrigation for crops plant local or native crops that do not require as much water plant gmo crops that do not require as much water switch from water intensive livestock farming like beef to less water intensive livestock farming like chicken switch from feedlots or kafos which can lead to soil compactation and runoff to more sustainable farming methods any of those would reduce the amount of water required to produce enough food for individuals same prompt different question describe one environmental disadvantage associated with increasing amount of meat in human diets other than the con associated with the consumption of water which we just talked about again environmental solutions more land is required to produce the same number of calories from meat as from plants the use of animal feedlots to raise animals generates large amounts of waste this contaminates ground in surface waters animal feedlots increases incidence of disease in livestock has an unpleasant odor and increases water pollution overgrazing can occur because we have too many animals in one area and cattle release greenhouse gases such as methane which can exacerbate global climate change sorry about that guys i had a leftover from the previous one so we&#39;ve got our over grazing which is on both those slides there and then cattle releasing greenhouse gases such as methane so there&#39;s there&#39;s one two three four five of them including that methane whoops all right so what should we take away from today things to remember remembering a few key do&#39;s and don&#39;ts for your free response questions can increase your scoring potential in order to earn full credit you must show all your math work as well as the units in each step of your calculations it&#39;s going to be really really good to get familiar with science practice 7 which is environmental solutions and how to justify your answers there be sure to reference a stimulus image graph or table if you&#39;re asked to provide evidence and you have a graphical stimulus and of course careful reading of the prompts for context clues will give you a big advantage when it comes to earning points so once again i am soliciting your help with clarification and information what can i do to make things clearer and better there&#39;s your google feedback form there&#39;s your qr code lay it on me and give you a second to grab that of course i&#39;m going to answer some selected submitted questions you might get a shout out at the beginning of ap daily live video 3. be sure to tune in to us preview of that video we&#39;ll go with clarifications and answers to submitted questions for ap daily live video 2 just like we did today content review on earth systems lots of visual models in this one of course frq modeling with connecting science practices to content knowledge interactive practice on concepts in video three here&#39;s your kahoot tell us what you got there&#39;s your kahoot url your game pin and your qr code gamepin is zero zero five seven eight two seven nine five i loved seeing everybody play yesterday have at it friends as always thanks for watching and i&#39;ll see you tomorrow night you

Transcript for:Day 2: Environmental Science Review

Transcript for:
Day 2: Environmental Science Review