this movie covers subtopic 8.4 human systems and resource use under the main topic of IB ESS topic 8 human systems and resource use the significant idea number one for this subtopic is that human Herring carrying capacity is difficult to quantify you need to be able to evaluate the application of carrying capacity to local and global human populations recall that the definition of carrying capacity is the maximum number of a species or load that can be sustainably supported by a given area at the carrying capacity K the population stops growing as resources are maxed out as illustrated in this graph where n is the population of a certain species it is possible to estimate the carrying capacity of an environment for a given species however this is problematic in the cases in the case of human populations for a number of reasons one reason it's difficult to measure human carrying capacity is that humans use a great range of resources much more than just we eat what we eat and drink look at this map it shows which exports make the most money for individual countries look at the range of resources in addition to food and drink like capital goods in the USA which includes air aircrafts and transistors in Canada Europe and South America we've got motor vehicle parts and transport equipment just think of all the resources required to produce that stuff then there are textiles metals gems coil coal and oil this is a complicated mix of resources again much more complicated than the resources a deer or bird might need another reason it's difficult to measure human carrying capacity is that humans substitute resources with others if the resources run out for example they substitute wood for coal or solar energy for oil or apricots for peaches in substituting they can extend their carrying capacity at least locally another reason it's difficult to measure human carrying capacity is that resource use varies from individual to individual and country to country for example look at this map of per capita meat consumption in countries worldwide clearly the United States consumes more meat than India another reason human carrying capacity is difficult to quantify is that we import resources from outside our immediate or local environment so we cannot just look at the local environment to see how many people it can support it might increase the carrying capacity at a local level but it will not influence global carrying capacity or it might decrease it if the United States imports 10 to 30 percent of food that allows more people to live in this area however that food comes from somewhere else in the world thus affecting the glory global carrying capacity developments and technology lead to changes in the resources we use for example the use of solar panels can reduce the consumption of fossil fuels reducing the pace of climate change thus increasing human carrying capacity right again that imp that makes it difficult to quantify human carrying capacity what are the different approaches to increasing human carrying capacity eco-centric smae try to reduce their use of non-renewable resources and minimize their use of renewable ones some may try to drop off the grid meaning they become self-sufficient through the use of solar energy for electricity collecting rain water growing their own food etc while techno centrists may argue there is no limit to the human carrying capacity because technology will have the solutions for human impact for example more fuel-efficient vehicles will stretch out the time.if oil is fully depleted genetically modified crops can increase fooled yield allowing us to feed more people this figure shows a general diagram of a linear example a human impact which increases linear with the population such as transport emissions where some change for example a drop in the average distance traveled in private motor vehicles which results in a shift of the curve and an increase in the number of people that the area can accommodate before the limit is reached the carrying capacity will have increased we don't know whether such changes might occur in the future therefore it's difficult to quantify human carrying capacity similarly this figure shows a sigmoidal example which such which could be soil erosion where some change for example widespread improvement in soil conservation measures results in a shift of the entire curve and an increase in the number of people the area can accommodate before the limit is reached another example of the of behavior influencing carrying capacity is visualized with this figure and it could be storm water causing a discharge of untreated sewage where the shift in the curve might be a real result from an increased uptake and installation of domestic air tanks again shifting the curb and allowing more people to supported by the area recall the Malthusian theory proposed in 1798 that set the idea forth that the population can never increase beyond the food supply is necessary to support it when the population reaches this critical point there will be war famine and disease in 1976 Paul Ehrlich also proposed that when the population reaches 3.5 million there will be famines and struction and that feeding a population of 6 billion would be totally impossible so far both of these predictions of disaster have been incorrect so what does that mean for the future significant idea number two the ecological footprint is a model that makes it possible to determine whether human populations are living within carrying capacity an ecological footprint is the area of land and water required to support a defined human population at a given standard of living the measure takes into account the area required to provide all the resources needed by the population and the assimilation of all wastes an ecological footprint is a model used to estimate the demands that human populations place on the environment an ecological footprint is the area of land and water required to support a defined human population at a given standard of living the measure takes into account the area required to provide all the resources needed by the population and the assimilation of all wastes you need to be able to compare and contrast the differences in the ecological footprints of two countries and evaluate how environmental value systems impact the ecological footprints of individuals or populations ecological footprints may vary significantly from country to country and person to person and includes aspects such as lifestyle choices or environmental value systems productivity of food production systems land use and industry if the ecological footprint of a human population is greater than the land area available to it this indicates that the population is unsustainable and exceeds the carrying carrying capacity of that area here you see a map illustrating the fact that an ecological footprints vary from country to country high on the list United States low sub-saharan Africa let's compare to Western world countries to see what might influence the differences in eco djegal footprint the netherlands with an ecological footprint of five point two eight grant global hectares per capita with the united states with an ecological footprint of twelve point two two global hectares per capita what might influence these differences one could be the different lifestyle choices and the environmental value systems regarding certain practices such as transportation in the netherlands with the rise in car numbers there came a huge rise in the number of deaths on the roads in nineteen seventy one more than three thousand people were killed by motor vehicles 450 of them children in response a social movement demanding safer cycling conditions for children was formed it was called stop de kinder morte stop the child murder furthermore the dutch faith in the reliability and sustainability of the motor vehicle was also shaken by the Middle East oil crisis of 1973 when oil-producing country stopped exports to the US and Western Europe these two pressures helped to persuade the Dutch government to invest in prutte improved cycling infrastructure and Dutch urban planners started to diverge from the car-centric road building policies being pursued throughout the urbanized West biking is very much a part of Dutch culture and mindset and is often the preferred mode of transportation and commuting in the US however it is very difficult to get around in most towns and cities without a car the Netherlands bikes entered a vie environmental value system versus the US car centered environmental value system might contribute to the differences in ecological footprint the Netherlands is a small densely populated country and it does not have the resources thought to be necessary for large-scale agriculture yet it's the globe global it's the globe's number-two exporter of food as measured by value second only to the United States and the United States has 270 times its landmass the Dutch use climate controlled indoor farms that require less land mass and less chemicals than traditional outdoor farming the country is a global leader in the exports of tomatoes potatoes and onions and the Netherlands is the second largest exporter of vegetables vegetables overall in terms of value more than a third of all global trade and vegetable seeds originates in the Netherlands again how did it get to this environmental value systems 20 years ago the Dutch made a national commitment to sustainable agriculture under the motto twice as much food using half as many resources since 2000 the Dutch have reduced dependence on water for key crops by as much as 90 percent they've almost completely eliminated the use of chemical pesticides on plants in greenhouses and since 2009 Dutch poultry and livestock producers have cut their use of antibiotics by as much as 60% finally let's consider electricity consumption per household twenty four point two three billion kilowatts in the Netherlands compared to one point three six trillion kilowatts in the United States that's 56 times more electricity consumption per household then the Netherlands this difference in household consumption also illustrates that ecological footprints can vary from person to person again all of these choices contribute to the Netherlands lower ecological footprint as compared to the United States degradation of the environment together with the utilization of finite resources is expected to limit human population growth by now in this course you are familiar with the impacts of farming deforestation you to occasionally biodiversity and global warming all anthropogenic Rize results from our presence on earth needless to say if human populations do not live sustainably they will exceed the carrying capacity and risk collapse on that cheery note this ends subtopic 8-point fewer human systems and resource use here is a summary of all that was covered in this movie this ends the movie for IB ESS topic eight point for human systems and resource use the slides were created by me dr. Nina Markham image citation is placed under the image if all images on a slide are from the same source the source is simply cited at the bottom of the slide another resource for you is your IB ESS textbook whether in hardback form or online such as cognitive thank you for listening