hey everybody it's mr. Smith and today I'll be covering topic 1.3 which is aquatic biomes so today we'll focus on factors that determine where aquatic biomes are found how the species that live in them are adapted to live there and the overall characteristics of each aquatic biome our objective for the day is to be able to describe the global distribution and environmental aspects of aquatic biomes we'll also look at different freshwater biomes and how they're an important source of drinking water we'll also look at different marine biomes which means ocean based biomes and we'll look at how they are an important supply of oxygen globally and an important sink for carbon dioxide globally and then finally we'll practice explaining an environmental concept and process at the end of today's video so first we'll cover four characteristics of aquatic biomes salinity refers to how much salt is found in a body of water and it determines which species can survive in this body of water and whether or not it's suitable for drinking water then we have depth depth is going to influence how much sunlight can penetrate the surface of the water so how much sunlight can reach the plants below the surface for photosynthesis so flow is the movement of water and that's going to determine which plants can survive in that body of water it's also going to determine how much dissolved oxygen will be found in the water because rivers and streams and rapidly moving bodies of water allow for better mixing of air and water which leaves some more dissolved oxygen in the water and then finally we have temperature this is very important because the warmer a body of water gets the less dissolved oxygen it can hold and therefore the less aquatic life it can generally support and that's because organisms in the water especially animals are going to require a lot of oxygen from that water so needs to have dissolved oxygen in order to support those animals so rivers are generally going to have high dissolved oxygen and that's because the movement of the water facilitates the mixing of air and water which leads to oxygen dissolving into the water we're also going to see high levels of nutrients found in the sediments that are carried along the bottom of rivers lakes on the other hand are standing bodies of fresh water and this is really important that they're fresh because that means the air a source of drinking water around the world next we have the different zones of a body of water and so the littoral zone is the shallow water around the edge of the lake or the pond and it's going to have what we call emergent plants so these are things like reeds and cattails where the roots of the plant are embedded in the bottom of the body of water but then most of the plant extends up out of the water the limb netic zone is this Zone in the middle and this is the zone where light can reach and so where photosynthesis is able to take place then we have the pre-funding zone which is too deep for light to reach and so there's not going to be any photosynthesis happening in that zone and then finally we have the benthic zone which is kind of like the murky bottom of the body of water and it's going to feature things like invertebrates that are gonna live in that murky bottom and the soil that's down there it's gonna be very nutrient rich because of all the sediments they are containing organic materials freshwater wetlands are areas where the soil is submerged or saturated with water for at least part of the year but it's still shallow enough for what we call emergent vegetation remember that's plants that have their roots in the soil but then extend up and out of the surface of the water another key distinguishing factor is that the plants that live in wetlands have to be adapted to live with their roots submerged in water most plants will die if the roots are totally submerged in water and that's because they won't get enough oxygen they'll essentially suffocate but plants like cattails or lily pads or Reed's all have adaptations that allow them to survive in submerged soils that is the key distinguishing factor of a wetland they're very important because they have a whole host of benefits one of them is that they store excess water during storms which is going to reduce the damage from flooding wetlands also recharge groundwater by absorbing rainfall into the soil and so that's going to refill aquifers and other underground sources of water that humans rely on they're also going to provide a natural filtration basically so the roots of the plants are going to trap pollutants that may be in stormwater runoff and prevent those pollutants from getting down into the groundwater beneath and then finally they're just a great habitat for a whole host of plant life because there's so much water and because the sediments here contains so much organic material which provides nutrients for those plants so really really diverse and productive biome here we have three examples of different types of freshwater wetlands and we'll talk about how plants in each habitat are uniquely suited to those conditions so we have a swamp here that's going to feature cypress trees which are a type of coniferous or pine tree that are uniquely adapted to survive living in submerged soils then we have marshes they're also going to have Reed's & cattail which like the cypress tree are uniquely adapted to survive with their roots totally submerged in water and then finally we have a bog and a bog is characterized by extremely acidic soil and so we have trees like the spruce tree and a species of moss called Spagna moss that are uniquely adapted to survive in these very acidic soils so we can see in each type of wetland here the plant species that are found there are uniquely adapted to survive in those conditions so far we've just talked about freshwater biomes and upcoming we'll talk about marine or ocean biomes but we have to first cover estuaries which are sort of an in-between between fresh and saltwater biomes so they are a mix of fresh and saltwater because they're where rivers empty out into the sea and so they're going to be very productive biomes and that's because there's going to be really high levels of nutrients contained in the sediments that are deposited in estuaries by the river so the river carries all of these organic sediments and then it deposits them in the estuary when it opens out into the ocean so that's gonna make the floodplains of rivers the areas where rivers flood up onto the land surrounding them or deltas where rivers open out to the ocean it's gonna make them have really fertile really productive soil so one type of estuaries a salt marsh these are estuary habitats found along the coast of temperate climates and they're gonna be really important breeding grounds for a ton of different fish and shellfish species so they'll swim into the salt marsh lay their eggs which will hatch and then they'll swim back out to the ocean and live the rest of their life really really important to supporting a bunch of different marine organisms here's a picture of it here so you can see it's kind of meandering opening of this river gradually out into the ocean then we have mangroves mangroves are really unique habitats there are estuaries that are found only in tropical climates so it's got to be a lot warmer Rainier and the mangrove swamps are characterized by mangrove trees these are really neat trees that have these super long stilted roots and so the mangroves you can see here basically sit up perched kind of on these roots and the roots are really key to the habitat they are going to stabilize the shoreline so they're gonna anchor the soil in place protect it from storm surges or really high winds they can absorb a lot of water when there's excess water from rainfall which will prevent flooding and then finally they're gonna also provide a super-important habitat for a bunch of different fish species that are going to basically swim among these roots fry and protection from predators find food to eat and so they're really vital estuary habitats next we have the coral reef so the coral reef is an ecosystem found in warm shallow waters beyond the shoreline really important to understand that it is one of the most biodiverse ecosystems on earth and it is the most biodiverse ecosystem found in marine biomes it's going to feature a mutualistic relationship between coral which is an animal and algae which is a plant so coral taking carbon dioxide out of the ocean and they're gonna create a calcium carbonate shell which we refer to as the reef it's their exoskeleton this is going to provide a home to the algae so the algae will actually live in the coral reef but then what they'll do is they'll take in some of the carbon dioxide that the coral give off through respiration and they'll use it for photosynthesis to make sugars these sugars then fuel the coral and provide them with an energy source really important to remember that this is a mutualistic relationship meaning that neither organism could survive without the other but when they live together in this mutualistic way they're able to live in an area that neither of them would be able to survive in without the help of the other next we have the intertidal zone intertidal zones are basically a narrow band of cosine between low and high tide so when the tide moves out each afternoon it's going to leave a lot of this area exposed to sunlight um there's also going to be a lot of crashing waves which requires the species that live in the intertidal zone to be able to basically hang on to the rocks there and anchor themselves so we'll see that species like barnacles sea stars and crabs are we're going to have adaptations that allow them to attach themself to the rock and resist being pulled out when the tide goes out another adaptation that they need to have is a tough outer shell or tough skin that prevents them from being dried out by that harsh sunlight that they're going to be exposed to at low tide this prevents desiccation which is basically the drying out of the organism what we'll see here when we look at this diagram is that different organisms are uniquely adapted to live at different levels of the intertidal zone so for example we have the spiral rack which is a type of seaweed it's adapted to live at the high tide zone because it can actually kind of curl up on itself and secrete a mucus which acts as kind of a moisturizing substance that prevents it from drying out during low tide so big important takeaway from the intertidal zone is that the organisms have to be uniquely adapted to live at the different areas found in the intertidal zone and finally we'll end with the open ocean so the open ocean we should know is a very low productivity biome per unit of area so per kilometer of the ocean it's much less productive than a kilometer of the tropical rainforest this is because only algae and phytoplankton can survive in much of the ocean it's just too deep for most plants to survive so although it has very low productivity per unit of area it's such a large biome and it covers so much of the earth that all of the algae and phytoplankton that live in the ocean produce a huge portion of the oxygen that we need on earth in order to survive it's also going to be an important sink for carbon dioxide meaning that these organisms are going to absorb a lot of carbon dioxide out of the atmosphere and that's going to mitigate and reduce the impacts of global warming because it takes in dioxide out of the atmosphere we have a couple zones we should know in the ocean we have the photic zone which is the area that sunlight can reach so that's the area where we will see photosynthesis occurring then we have the aphotic or the abyssal zone this is the zone that is too deep for sunlight to reach and so there's no photosynthesis that's going to be occurring here really important we should know that the organisms that live in the abyssal or the aphotic zone are going to need adaptations to survive there so many of them have an adaptation called bioluminescence which allows them to glow giving themselves a source of light so they can see and navigate in this dark ecosystem and also they're going to need to be adapted to sustain extremely high pressures due to all of the water that's above them so big theme from all of the aquatic biomes we should know is that the organisms that live in them need to be uniquely adapted to survive the conditions found in those biomes a practice frq for topic 1.3 today will involve concept explanation so I want you to identify an organism that's found in an aquatic biome and explain how that organism is uniquely adapted to live in that specific biome alright everybody thanks for tuning in today don't forget to like this video if it was helpful subscribe for future apes video updates and check out other notes over here to the side and as always think like a mountain write like a scholar