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all right hello welcome to the soil
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organisms lecture so the first part
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we're going to talk about animals plants
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and algae so right here this first slide
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it's a video by a company called 59° out
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of Sweden on how to get the perfect soil
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so when you click on the lecture slides
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or have the lecture slides glowing as
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you watch along with the narrated
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lecture right here I would hit pause on
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this and I would click on the link there
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and it should take you to the YouTube
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video to watch that video on how to get
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perfect soil so in terms of this lecture
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what are we what what do we want to talk
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about when we talk want to talk about
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soil organisms so soils are teeming with
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life forms that's what makes it fertile
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soil so when we talk about soil by our
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definition it must contain microbes must
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have microbial activity and all the soil
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life forms are beneficial to soil
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development some are pathogenic some are
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problem causing give pathogens to plants
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so when we talk about fertile soil when
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we talk about the idea of the soil being
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its own ecosystem and the soil being
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alive these organisms are big part in
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that these life forms these organisms
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are responsible for human development
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you miss has a very high exchange
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capacity and water holding capacity and
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is great for soil structured fertility
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like we talked about before and so
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because of that or the reason for that
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is because of these organisms and the
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role that these organisms play within
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the soil and allowing this to happen to
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where they're going to make nutrients
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available and they're going to help out
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with that exchange capacity and they're
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going to be moving around and creating
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pores and allowing for water and air to
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move in between all of this is is work
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done by these organisms and make soil
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this alive
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Ecosystem this this fertile soil this
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this absolute foundation for everything
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else that happens so the first animals
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we'll talk about our vertebrates so
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animals with an internal skeleton
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they're not really very important in
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terms of what we're talking about they
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can't actually be pests they can destroy
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crops where they do where we do find
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importance for them is that they can
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aerate soils and kind of a they plow the
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soils in a way by doing grazing and so
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because they graze and they basically
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cause a disturbance and kind of allow
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the soil to be plowed in a way they
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basically put in that disturbance to
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kind of kick-start the succession
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process again also in leaving their
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feces they can help help start the
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decomposition process because they leave
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something there and then the other
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organisms now have something to feed off
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of and start that process of turning
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things things from the above the soil
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into soil earthworms are one of the one
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of the group of round worms and
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earthworms are very important in terms
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of doing organic degradation so the idea
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is that there one of these one of these
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organisms that's very important in terms
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of the idea of causing things to degrade
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causing things that weren't soil to now
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become soil and taking that houmous and
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that partially degraded organic matter
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and turning it into degraded organic
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matter or topsoil they are helped
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produce kind of a super human because it
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has a very high exchange capacity and
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that makes it easier for the minerals
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are sorry for the nutrients to go back
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and forth between the plant roots and
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the and the soil which is absolutely a
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useful thing average healthy soil has
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over a million
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earthworm's per acre and they process
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about two tons of organic matter daily
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so two tons is is a high high number in
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terms of organic matter if we just think
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about you know like a quarter ton truck
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or a half ton truck and think about
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filling that up and you're talking about
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you know if it's a half ton filling it
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up four times if it's a quarter time
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filling it up eight times with organic
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matter and that's the amount of organic
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matter that an earthworm or that a group
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of earthworms will will process so it's
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they're extremely important in the soil
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they're mostly in the top six inches of
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the soil the big problem we face with
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agriculture not so much in forestry but
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definitely with agriculture is that they
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can easily be killed by by tillage by
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fumigating by flooding or if you have
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air air in areas with droughty soils so
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that's why irrigation like we talked
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about before
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extremely important that's why getting
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the right amount of water and not being
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flooded is important and that's also why
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when you'll see other practices like not
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tilling the soil and and newer
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agricultural practices coming out
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because we understand now how important
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these organisms are in this soil
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development process so here's just some
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of those examples of different critters
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that are in the soil so we've got our
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earthworms down on the left you got a
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nice example of a vertebrate on our
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right and then just kind of up above the
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different things that they can do within
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the soil as they as they move around and
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and how they're gonna change the look of
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the soil in terms of arthropods think of
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like our bugs and insects so when we're
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specifically talking arthropods we're
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saying hard exoskeletons and segmented
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body parts including legs so ants
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termites millipedes centipedes beetles
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these sorts of things
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these ones feed on decaying vegetation
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and turn the soil so the idea is that
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they're going to eat decaying vegetation
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and then they're also by moving around
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and by digging around they're going to
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kind of turn the soil and kind of
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naturally till the soil themselves
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however clear ground cover around the
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holes which can open up can lead to soil
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erosion so sometimes if you get too big
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of holes or you get a lot of holes that
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can lead to a good amount of soil
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erosion but usually with these bugs
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they're they're good outweighs they're
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bad and so over on the right here we
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have an example of food web and showing
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the organic debris that then gets ate by
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the fungi and the bacteria and then the
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fungi gets ate by the Beatles and the
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mites and the springtails
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and eventually you know they're the
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other things that are within the soil
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like the earthworm snails and slugs and
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those things get eaten by ants and so
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you can see that these these arthropods
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they have their their you their use in
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the food chain there they're there to
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basically feed on on vegetation feed on
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these other animals and kind of keep the
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the food web happening within the soil
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gastropods coiled shelled skeletons and
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singular muscular foot for creeping
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we're talking about slugs and snails and
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as a proud UC santa cruz banana slug I
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now see much more the importance of
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slugs than I used to definitely was one
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of those kids who would throw snails
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around and not and you know crush those
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shells on accident sometimes on purpose
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and just did not understand the
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importance to soils and to vegetation so
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one of the the benefits of gastropods is
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that they do feed on decaying vegetation
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but one of the negatives is that they
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feed on plants as well and
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that's why people were okay with you
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know kids destroying slugs or snails and
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you know they see it more as a pest they
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don't understand that they're also
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they're eating that decaying vegetation
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turning that organic matter into human
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sand into soil and there are also good
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soil builders but really it's the idea
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that people see them as plant pests
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that's problematic
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nematodes nematodes are almost
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microscopic unsegmented round worms so
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remember earthworms were also in that
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round worm category so we also have
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nematodes which are also a form of round
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worm now nematodes can feed on organic
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matter they could also be Pradesh asan
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other nematodes and they can be
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parasitic on plants so they're kind of
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hitting that trifecta of they're really
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good in terms of feeding on organic
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matter helping it degrade more they also
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are a positive in that they eat other
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nematodes but then they have that
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negative of being parasitic on plants
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just similar to similar to snails in
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that they're they're seen as a pest on
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plants some of the species of nematodes
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are very very bad for plants and putting
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out very bad pathogens one method for
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for control is a soil FEMA gation so
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putting pesticides into the ground but
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the big thing is that kills all the
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other organisms as well and so if you're
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just trying to kill the nematodes you're
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a-- and you're gonna kill everything
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else as well with fumigation some
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nematodes can create houmous be a
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digestion of organic matter so that it
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that becomes a tree positive in terms of
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soil and they can crawl in soil pores so
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they really do prefer sandy soils
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definitely not clay soils because it's
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too hard for them to move around in the
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clay soils so the size of nematodes is
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very small not quite microscopic but not
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that far from it because on the left
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we have a human hair strand and then on
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the right we have a nematode so we're
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looking at you know roughly something
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like the size of a human hair strand so
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very small but not quite microscopic in
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terms of plants what we really want to
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talk about is the rhizosphere which is
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the volume of soil surrounding plant
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roots that physically and chemically
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interact with the root the word raizo
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itself just means relating to the root
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or roots and it's a very complex
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ecosystem of microbial species now well
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shouldn't an ecosystem be a big thing
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with this the amount of microbial
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species we're talking about bacteria
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fungi nematodes we're talking about
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things that are very small and in just
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millions and millions and millions and
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millions of them so it's it's its own
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tiny little ecosystem within the the
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bigger ecosystems it's got in the
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rhizosphere you've got symbiotic
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relationships with plant roots but you
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also have parasitic relationships with
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plant roots so just kind of going over
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that terminology again sand by a
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symbiotic relationship they're getting
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good out of it each side is getting good
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out of it parasitic one is feeding off
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of the other and one is one is
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benefiting but the other one is
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suffering you can get complex chemical
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reactions within the rhizosphere
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including antibiotics attractants
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repellents and and also exchanging food
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sources between the roots and the
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microbes the idea of exchanging water
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and minerals and for sugar basically and
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then usually you get higher organic
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matter and more acidic in the soil
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around the rhizosphere
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then you do around the the rest of the
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soil and you also get better drainage in
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aeration because you've got the roots
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pushing through this area and so they
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they they basically leave a tunnel
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system it's all set up for when the next
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plan
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or when the other roots want to come in
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and spread out so you so you have better
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drainage in aeration and then you
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usually get the higher organic matter
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because you've got these animals or
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these organisms hanging around the area
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around the plants and what's interesting
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those it's it's going to be more acidic
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around this area so you really want to
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take a look and thinking about your pH
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you already know that we would prefer
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that six and a half to seven and a half
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pH you're probably going to end up a
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little more on the acidic side so you
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already kind of know what you need to do
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in terms of trying to help out your
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plants if we've studied pH well enough
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so looking at the rhizosphere so on the
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right hand side here we got a diagram so
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this area in the blue would be the
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rhizosphere and we'd see our root hairs
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and our epidermis and the root cap and
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all these different parts of the root
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that are out there in terms of a diagram
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if we look on the left what does that
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actually look like so this is what we
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call a plug where everything that's kind
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of that orangish color oranges reddish
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color that's that soil and then you see
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the plant rooting in there and you can
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see all the different roofs the long tap
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root and the lateral roots going off to
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the side of it and you can see how they
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merge into the soil so this slide right
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here has another video on the
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rhizosphere so make sure to hit pause
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right here on click on the lecture
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slides watch the the rhizosphere video
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and just kind of understand that that
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complex ecosystem that's happening below
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the ground below the plant our other our
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other topic that we wanted to talk about
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in part one is the algae so all algae
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need lights so they'll be in the top
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half inch of the surface we get two big
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categories of algae so we got green
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algae and they're green because they
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contain chlorophyll and so their major
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producers of organic matter
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such a sugar starch cellulose that are
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going to end up in the soil so they're
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important in terms of the soil because
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they've got something to give which is
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they've got the sugar produced from
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photosynthesis and so they're willing to
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give that to the soil and the soil man
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is willing to say well here what about
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these nutrients and from these minerals
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and what about this water and that that
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kick starts that exchange between the
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two in terms of diatoms they're algae
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with silica in cell walls so they can
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also for this photosynthesize but much
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less than green algae after all they can
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do more they'd be green algae but
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diatomaceous earth can be made out of
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diatoms and so hopefully you're saying
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what is diatomaceous earth and then you
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get to this next slide and you find out
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diatomaceous earth is it's basically a
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insecticide or some sort of type of
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insect killer that's made from the
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fossilized remains of tiny aquatic
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organisms called diatoms or this algae
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called diatoms and their skeletons are
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made of silica and so over a long period
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of time the diatoms accumulate are
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accumulated in rivers streams lakes and
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oceans and so what they do is they go in
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mind these areas especially areas that
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used to be covered in water and aren't
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anymore so like the Kahn River
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floodplain the current River is still
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flowing there but a lot of the area that
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used to be the floodplain is not covered
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by water anymore so that's an those are
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areas where you go and find people
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mining for silica and trying to pull out
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things that you could the silica that
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you can use to make diatomaceous earth
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diatomaceous earth products you can use
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them against bed bugs crickets
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cockroaches fleas ticks pyres and other
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pests so it's just kind of an
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interesting thing with we might not
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think of a insect killer be made out of
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algae but that's kind of that's what
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diatomaceous earth is so right
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I've put some questions you can pause it
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write down the questions try and answer
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it just that way you can kind of start
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preparing yourself for the test and I'm
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gonna go ahead and go on to part two so
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we've got fungi lichens bacteria and
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microbial activity in the second part
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here so if you need a break
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I'd say pause it here write some stuff
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down take a break if not we're gonna
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plow through so right here I've attached
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to video so one of them is a video for
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metallic atom iam Sciences kind of takes
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you into the soil and let you see what's
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going on beneath our feet which i think
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is is really cool and then another video
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from 59° about that goes into the
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different parts of the soil food web and
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really getting comfortable with that
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idea of what's in the food web and how
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did these organisms all fit and why do
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they end up having to work together so
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our first part of part two is extremely
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important and that's the fungi so it's a
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whole kingdom of life-forms comprised of
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single or multicellular forms they're
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heterotrophic with no true organs and
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mostly just thread-like mycelia
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so you can get molds mildews rough Smuts
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mushrooms those are all part of the
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fungi we're really usually when we think
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of fungi or fungus we think of mushrooms
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because that's what we can see above the
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soil but we got all of these other parts
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it's a whole kingdom of organisms so
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that's way up in terms of when we're
00:19:30
talking about species and we're talking
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about Kingdom you've got a lot of levels
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before you get all the way up to Kingdom
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so lots of things are within the kingdom
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of fungi these are major decomposers of
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organic matters and complex minerals so
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they are absolutely great soil builders
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so hopefully in those videos you saw the
00:19:52
web that can be created by by the
00:19:54
mycelia
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around the roots and really allows them
00:19:58
to get that extra
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and stretch out that that root zone to
00:20:03
where they can get lots and lots of
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minerals and lots more water and then
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that helps them become these great soil
00:20:10
builders because it really increases the
00:20:12
exchange capacity within the soil the
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one negative to fungi is that they're
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they do complete compete with the plants
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for some minerals many species are major
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plant pathogens so you do have them
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causing some problems to plants but
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overall in terms of fungi they're much
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more positive for the soil and then they
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are negative the one big thing though
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with with fungi because of the way they
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are and hopefully any of you who are
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used to fungi like mushrooms and things
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like that our understanding of this they
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mean well aerated soils with lots of
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organic matter and moisture so if I'm
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gonna go mushroom hunting if I'm one of
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those people who finds that of interest
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where am I gonna go I'm gonna go into
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forests and I'm gonna go into forests
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where it rains quite a bit because
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that's an area that I know is going to
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have a lot of organic matter and a lot
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of moisture so the soils going to be
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well aerated and so that makes sense
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having soils that get farmed a lot and
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get compacted to where there's not a lot
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of space for air and water to travel
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through and there's not also gonna be a
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lot of organic matter on the soil I'm
00:21:28
not gonna see a lot of fungi within that
00:21:31
area so that's also another reason when
00:21:33
people talk about trying to change
00:21:35
farming practices knowing the importance
00:21:37
of fungi in terms of being great soil
00:21:39
builders and being a major decomposer of
00:21:41
organic matter and help helping out in
00:21:44
this this idea of exchange between the
00:21:50
soil and the plants and the organisms
00:21:52
because we know of its importance
00:21:55
that's where where we start saying well
00:21:57
maybe these things we're doing
00:21:59
conventional agriculture could be a lot
00:22:01
better so just some examples of mycelia
00:22:08
on the right so that kind of just that
00:22:12
thread like struck
00:22:13
that can spread out throughout the soil
00:22:15
mushrooms down on the bottom left which
00:22:18
were all much more used to seeing and
00:22:21
then just an example of a water mold on
00:22:24
the top left
00:22:28
so mycorrhizae that's a fun fungi that
00:22:32
forms a symbiotic relationship with the
00:22:34
plant roots and the plants feed and
00:22:38
house the fungi and the fungi helps the
00:22:41
plants obtain more water and nutrients
00:22:44
so that's the big that's the symbiotic
00:22:47
relationship the plant feeds and houses
00:22:49
the fungi it lives on the plant and
00:22:51
attaches on the roots and then the fungi
00:22:54
helps the plant to obtain more water in
00:22:56
nutrients by spreading out farther then
00:22:59
the plant roots can go and it can
00:23:01
increase usable soil volume up to a
00:23:03
hundred times and also it secretes
00:23:06
chemicals that rapidly degrade the
00:23:08
minerals to release plant nutrients such
00:23:11
as phosphates so that becomes an
00:23:12
important part to this whole to this
00:23:16
whole process where really it it helps
00:23:19
to get the plant to release nutrients
00:23:22
and those nutrients would not release
00:23:24
without the without the mycorrhizae so
00:23:26
that's what's really important to
00:23:28
understand with fungi and why it's
00:23:30
important in terms of being a part of
00:23:33
the soil is that it it without it some
00:23:38
of these nutrients would not be released
00:23:40
and we know that soil needs certain
00:23:42
nutrients and the plants need certain
00:23:43
nutrients you got two major forms of
00:23:46
mycorrhizae you got ecto mycorrhizae and
00:23:48
you got endo mycorrhizae so the ecto
00:23:50
Micra is he forms a sheath around the
00:23:52
roots and can penetrate between the root
00:23:55
cells only whereas the endo mycorrhizae
00:23:57
penetrates into the host cell so the
00:24:00
ecto mycorrhizae forms a protective
00:24:02
sheath around the roots and then can
00:24:06
penetrate between the root cells only
00:24:08
whereas the ecto mycorrhizae actually
00:24:10
goes into the cells and so over 80% of
00:24:14
crop species and all perennial tree
00:24:16
species contain mycorrhizae and in many
00:24:20
cases the the fungi like I said is
00:24:22
necessary for survival of the plant
00:24:24
because it can go that extra
00:24:26
to those extra areas within the soil
00:24:28
that the plant which just can't reach so
00:24:34
here's just a couple examples of just
00:24:36
plant roots with that with that
00:24:39
mycorrhizae around it and stretching out
00:24:44
our second category was lichens so it's
00:24:48
a symbiotic relationship between an
00:24:50
algae and a fungus so the fungus houses
00:24:52
houses the single-celled algae so the
00:24:55
algae lives on the fungus and then then
00:24:59
it photosynthesizes sugars for the
00:25:02
fungus so the algae can then
00:25:04
photosynthesize sugars for the fungus so
00:25:06
it gives it food
00:25:07
the fungus gives it a place to live and
00:25:09
grow nice symbiotic relationship these
00:25:12
lichens are major decomposers of rocks
00:25:15
and dead trees and that becomes
00:25:16
important in the idea that lichens are
00:25:19
one of the first creatures to show up in
00:25:21
terms of primary succession so when we
00:25:22
don't have soil lichens are one of these
00:25:25
things that can come in and sit settle
00:25:29
on the rocks can help that decomposing
00:25:32
process which is that basic start to
00:25:35
soil and so they play an important role
00:25:38
especially in primary succession and
00:25:40
lichens you can find them in all land
00:25:43
areas the world bacteria is huge in
00:25:48
terms of soil development and and as a
00:25:53
soil organism and as a participant in
00:25:56
this soil ecosystem so the number of
00:26:03
bacteria exceeds that of all the other
00:26:06
microbes in the soil so in one gram of
00:26:09
soil it can have a million bacteria now
00:26:14
in our minds bacteria because of what we
00:26:16
know can hurt us bacteria it has a
00:26:20
negative connotation but in the soil
00:26:22
bacterias is is a positive thing can be
00:26:25
a negative thing but definitely a
00:26:26
positive thing so in terms of
00:26:30
autotrophic bacteria they have energy
00:26:33
obtained from photosynthesis or certain
00:26:36
minerals well in heterotrophic bacteria
00:26:38
the energy is obtained from organic
00:26:41
forms in the soil so your most common
00:26:45
bacteria in the soil is going to be your
00:26:46
heterotrophic bacteria especially the
00:26:50
act acting on my seats but you can't
00:26:56
have some of this heterotrophic bacteria
00:26:57
being pathogenic mostly most of it
00:27:02
though degrades dead material to humans
00:27:04
which is perfect and important and
00:27:08
really good for our understanding of how
00:27:11
does how does that process happen so if
00:27:13
we say humans is parsley degraded soil
00:27:16
matter how did it happen how does poop
00:27:19
and how does dead animals and how do
00:27:21
leaves and twigs and all these other
00:27:23
things on the forest floor or on our AG
00:27:27
fields turn into soil and the first step
00:27:31
in that is going to be mostly this
00:27:33
bacteria and specifically the
00:27:34
heterotrophic bacteria autotrophic
00:27:37
bacteria also plays a part in that they
00:27:39
can oxidize minerals to usable form so
00:27:42
trying to get that nitrogen that's in
00:27:44
the atmosphere in the unusable form and
00:27:46
get it into that ammonia in the soil
00:27:49
which is a usable form and then also
00:27:51
then doing the denitrification and
00:27:54
getting it back out into the atmosphere
00:27:58
which takes us to the idea of nitrogen
00:28:00
fixing bacteria so the idea that that
00:28:04
they can change the gaseous form of
00:28:07
nitrogen in the atmosphere and change it
00:28:10
to that usable NH for ammonia that can
00:28:14
actually be nitrogen that's used within
00:28:16
the soil and becomes part of this
00:28:18
nitrogen cycling and and provides
00:28:20
nitrogen to the plants so you have
00:28:23
free-living nitrogen bacteria that live
00:28:26
in the soil pores and you got symbiotic
00:28:28
nitrogen-fixing bacteria which live
00:28:30
inside the plant roots free living
00:28:32
account for almost all the nitrogen
00:28:34
fixation on earth about 15 pounds per
00:28:37
acre per year that's a lot of nitrogen
00:28:40
fixation and then the symbiotic exists
00:28:43
mostly in the legume family so peas and
00:28:46
beans alfalfa clovers peanuts can also
00:28:50
do this as well but
00:28:52
mostly within this legume family you get
00:28:56
these bacteria that they're going to
00:28:59
live on nodules on the roots they're
00:29:02
going to put provide that ammonia to the
00:29:04
plants and then what do they get out of
00:29:06
it they get to live on the plant and
00:29:08
they get the sugars from the plant so
00:29:11
they get pumped up because they're
00:29:12
getting sugar and managing from the
00:29:14
plant and then in exchange they take
00:29:16
this nitrogen in the soil that's in this
00:29:19
gaseous form and turn it into ammonia
00:29:21
that then the plant can use and so
00:29:24
that's why anything that's in the pee
00:29:26
family being family alfalfa clover all
00:29:29
these things they don't need nitrogen
00:29:31
fertilizers because they do they provide
00:29:33
their own nitrogen so here's an example
00:29:37
of that idea of what's a what's a root
00:29:41
nodule and how are they living within
00:29:43
that nodule so if you look at the top
00:29:46
right here you've got your root hairs
00:29:47
and in the root hairs there's an
00:29:50
infection thread where the bacteria
00:29:51
works its way in and this is that
00:29:53
symbiotic bacteria and then it becomes a
00:29:57
nodule as it swells up and sticks out of
00:30:01
the root and so on the right there all
00:30:04
those little balls sticking out on the
00:30:07
roots those are the nodules and so if we
00:30:09
look at more like a close-up diagram of
00:30:12
it here's our here's our member of the
00:30:14
legume family because we see right where
00:30:17
it says the word photosynthesis just to
00:30:19
the left of it you see that nice bean
00:30:20
pod or pea pods and we know it's a
00:30:22
legume so we know it does this nitrogen
00:30:25
fixing it has ins nitrogen fixing
00:30:27
bacteria so we look at the roots and we
00:30:29
see those nodules down there and if we
00:30:31
were to zoom in with a microscope we'd
00:30:33
see all this bacteria living in that
00:30:35
nodule and it's there to be able to take
00:30:37
in the plant takes in that nitrogen
00:30:40
through stomata or through lenticels
00:30:46
whatever pores it has that they can
00:30:48
bring in the nitrogen and then it's
00:30:49
going to be this bacteria in the soil
00:30:51
that then is gonna change it to ammonia
00:30:54
and make it usable for the plant so it's
00:30:57
amazing when you really think about it
00:31:01
so just trying to kind of give you the
00:31:05
diet the whole
00:31:06
diagram of that so we've got nitrogen in
00:31:09
our atmosphere 78% of it the majority of
00:31:12
our atmosphere is nitrogen because when
00:31:14
we think about it we need oxygen but if
00:31:17
you think about human beings as a whole
00:31:20
of the earth there is way more grass and
00:31:23
way more plants and way more trees than
00:31:26
there are people so therefore our
00:31:28
atmosphere is way more nitrogen than it
00:31:30
is oxygen and the reason is we need that
00:31:34
nitrogen to make this soil and to make
00:31:37
the whole process and to create this
00:31:38
whole foundation of the earth that we
00:31:41
think of as as the soil ecosystem so
00:31:45
here's another look at it trying to put
00:31:47
everything into it so we got that
00:31:49
nitrogen in the atmosphere we got the
00:31:51
nitrogen fixing bacteria in the root
00:31:53
nodules
00:31:54
we got nitrogen fixing soil bacteria we
00:31:58
got some decomposers we got our little
00:32:01
vertebrate animal they're munching on
00:32:04
the plant and then pooping and then
00:32:07
we've got the plant roots decomposing
00:32:10
the parts of the plants decomposing and
00:32:12
the whole cycle all of this is that
00:32:15
nitrogen cycle will happen within the
00:32:17
soil and these organisms are crucial in
00:32:21
this cycle in terms of microbial
00:32:26
activity so the big thing to understand
00:32:29
with microbial activity is generally
00:32:31
conditions that are best for plant
00:32:32
growth are also best for microbial
00:32:35
activity so if you can grow plants
00:32:37
you're gonna have microbes and if you're
00:32:39
gonna have microbes in the soil then
00:32:42
that's fantastic because then you've got
00:32:44
all these little little things that want
00:32:48
to create organic matter and process
00:32:51
organic matter so what are those
00:32:54
conditions what what makes sense for
00:32:56
lots of microbial activity temperatures
00:32:58
about 80 degrees water to Field capacity
00:33:01
loamy soils that have that lots of pore
00:33:04
space but they can also move water well
00:33:06
and they can hold water well and a pH
00:33:08
close to 7 that's why that ideal plant
00:33:10
growth is six and a half to seven and a
00:33:12
half and overall this makes for good
00:33:14
fertile soil and so in temperate
00:33:17
climates like the continental US
00:33:20
regular precipitation becomes the most
00:33:22
important pact most important factor in
00:33:24
building the soil microbe population so
00:33:26
if you've got precipitation you're going
00:33:28
to have this great microbial activity if
00:33:30
you have an arid region that's where it
00:33:33
gets tough and where you lack that
00:33:35
microbial activity and that's why you'll
00:33:37
see a lot less organic matter in more
00:33:40
arid places even deserts where you see
00:33:42
no organic matter you're gonna not have
00:33:45
any microbial activity and that's why
00:33:47
your soil isn't good for being able to
00:33:50
grow plants good or use of good cultural
00:33:54
practices like crop rotation integrated
00:33:56
pest management and low tillage or no
00:33:58
tillage or conservation tillage will
00:34:00
help maintain this balance microbe
00:34:03
population and basically keep the
00:34:06
microbes happy because one thing that
00:34:08
could happen is if your microbes are
00:34:10
happy that's great they're very helpful
00:34:12
for your soil if the microbes don't have
00:34:14
what they need then they'd be making him
00:34:16
become pathogenic or the pathogenic
00:34:18
microbes start out numbering the helpful
00:34:22
microbes so micro microbes can be
00:34:25
helpful but they could also be
00:34:27
pathogenic and it really depends on how
00:34:30
healthy the soil is because when the
00:34:31
conditions are best for plant growth the
00:34:34
microbes are happy when it's not best
00:34:37
for plant growth that's when the
00:34:38
microbes didn't cause problems so for
00:34:42
part 2 here's some more lecture quiz
00:34:45
questions pause it write down the
00:34:47
questions put down your answers if you
00:34:51
have any questions you can always email
00:34:54
me or let me know here is a video that I
00:34:58
think sums it all up and does a great
00:35:01
great summary of everything and really
00:35:04
kind of puts the whole thing together
00:35:05
and probably and does it in my mind
00:35:08
better than I can so watch this video
00:35:10
let me know if you enjoy it because I
00:35:12
enjoy it I think it's great I think it
00:35:14
really sums it up and with that I'll see
00:35:18
you next time
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