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BIO 370 FINAL- Landscape Ecology

Terms in this set (24)

So when we're thinking about landscape structure, this includes, you know, several different things. You know, one theme, you see that, throughout the semesters, we try to define, define what we mean by like, landscape structure define what we mean by like, what describes the population, right? Its abundance, its density, its location, right? And within that location, the size and the shape of that location are important.

But so landscape structure includes this size, shape, composition, number position of patches in a landscape if we're thinking about something like vegetation. So it includes all these, all these defining characteristics, if we're thinking about the landscape, as it is we're looking down on earth, and we're thinking about these different areas and how we classify Okay, that's woods in that is wetland and that is you know, urban areas.

So a patch is a homogenous theory that differs from its surroundings. So what's an example that you know, from campus?? is area that differs from its surrounding How about the little forest area between wall and guess it's Hicks dining hall. Wow,
the planted area between like a river and the desert.
planted area between river and desert
like on the very bigs of the Nile,
like the wetland areas, like there's a spot right across from the golf course and campus by liking chapel, that significantly we wetter than the area that surrounds which would be maybe drier.

So you have an area of like wetlands that is surrounded by you know, golf course and parking lot. Essentially, you have these little patches like I think if you know it on coastal, you have these little patches of forest There used to be a lot more, but think about the patch of forest that is bounded by the tracks. The practice football field you know, cc us maintenance and facilities buildings, the post office, you know that that little forest there, you know that's a patch.

So you have this homogenous forested area surrounded by this other stuff. And so then the matrix is the element within the landscape that is the most continuous spatially. So I'm coastal campus that's pretty much like buildings mixed with manicured lawns, and parking lots. So like, suburban land use developable land.

So what about like patches on the Grand Strand? Whatever you like the dunes in between the road and the beach
that could be paired here. That's basically surrounded a lot by Urban stuff.

So if we zoom in, like this very here, what type of patches Do you see? What's
that marshland
looks like forest. But it could be some of this is like Morris land. Yeah. So we have some patches of like, wetland here a little more upwind for us? And what's the matrix?
What's the major picture here? Would it be like the residential communities that surround it? Yeah, the most continuous stuff is that you know, this residential if we if we saw in GIS if we you know, took this and mapped it all out, you know, we could calculate what percent of this area is this versus this or and you could break this down even further like, what percent is up in forest, what percent is this? What percent is you know, we have like stormwater retention ponds, impervious surfaces, what is what percent is golf course? So, yeah, I mean, we have these mostly, patches are mostly forested, and then mixed with some, you know, with a lot of residential development. Now, when we look at here, would you consider the patches here?
On land?
Yeah, I think that, you know, some agricultural fields, like some of this might be silviculture out here, but, yeah, this is a lot of forested lands, you know, with smaller patches of, you know, fields mixed in. So, it depends on where you are, but you can classify these things.

So, we have a patch, we have a matrix. So, we can, you know, a lot of times, there'll be ecological questions, trying to figure out how does this patch and matrix scheme or these different if we put different numbers at different levels to the landscape, like, what percent of the landscape is paved in an area or you know, what is suburban? What is open grassland?

You know, if we have a bunch of areas, you know, maybe 10 areas you're studying in in each year, you quantified percent, urban, agriculture and natural habitat, you just very broadly 10 areas You want to study the number of
hours, maybe great horned owls, to see if there's some sort of relationship between the number of great horned owls in an area and the different percentages of these habitats in the landscape. Where it could be, you know, a different species, maybe it's a reptile. We do this for fish, you know, What is there? What is the effect of different levels of agriculture on a stream? And how does that influence fish abundance, or the assemblage of fishes that the species that you actually find there?

So these are the types of questions that you can look at. And

it's the value of GIS because you can readily get these numbers. Okay. In this area, there are net, there's there are these national datasets, you know, in this area, what is the percent of intensive agriculture? What is the percent of, you know, use, it's like, hey, what is the percent that is silviculture, in growing trees, in all these different factors, and then try to see how those influenced, you know, assemblages, maybe it's bird assemblages, or reptiles, and so on and so forth.
And, you know, landscapes, they are structured by a variety of processes.

So how we, what we see on the landscape, you know, when we look out our window, when we look at the earliest aerial imagery, that happens for a variety of processes, we have geological processes, right?

So the underlying geology and things like, continents moving apart and coming together in and, you know, uplift of, you know, plates and forming mountains. Right.

So we have these very, you know, long timescale geological processes that influence the landscape.

Climate, right, influences the landscape. We you know, and we've talked about that, where were deserts most common?
Sounds like a good final question. 30, or 40 degrees 30, around 3030 degrees, north and south, right. And you have that climate there, because is that dry air just sucks everything off the landscape, because all in all, the water was lost in an air is dry, all of our water is lost in the tropics.

Right? So climate is controlling, you don't see a whole bunch of large tropical rain forest trees growing in southern Arizona, because, you know, the climate. And we know that that is dynamic. There are places in there's one place in Northern Africa that, you know, in general, it seems like every 10,000 years it it transitions, it has been moving between grassland and more desert, like. So you're shifting trends in it.

You know, the biggest factor in, you know, on a shorter timescale is humans, right? Humans have tremendously altered the landscape. So they have, you know, humans are the most influential modifiers of the landscape by far. That's not surprising, you know, I look at how the landscape around my neighborhood has changed. There have been 1000s of acres, I would say a rough estimate, at least, at least hundreds, but maybe 1000s of acres in the last four years that have been cleared. And I would say hundreds of acres of that now which was used to be forest has houses on it with people living in paved roads. And there are other hundreds of acres that are dirt that has been moved around to build houses and you know, paved roads and stuff like that.

So you know, humans were really good at changing the landscape quickly.

Fire another natural destructive events, you know, they change landscape quickly talking about this with Mount St. Helens. We, you know, fire has been in the news, a lot. With a slight Australia fires in the Amazon and you know California, they change the landscape as well.

You know on the on the right here is a nice annotator spotlight. You know a nice this is these are maps built in GIS. This is from Western Michigan, the Muskegon River watershed and looking how you know, it's been changed over time or how it's changed over time, this was over about a 90 year period. And this is land use within the Muskegon River watershed.

So this is basically showing the blue is water, this is forested, and this lighter color is cleared land, probably for agriculture, cc and 1890. You know, of course, did 1900 is basically been clear cut, right? And so that, you know, you have, you had a lot of clear cutting, occurring in the 1800s, the early 1900s, in the Midwest, in the northeast, you know, for the timber industry. And then as you move through time things, you know, don't change a lot in the 30s and 40s, probably with agriculture. But by the 70s, you see some of this clear cut land is now changing back to more forested area. We see that, you know, they're large, large, you know, very large swaths of land. almost the whole northern tier, Pennsylvania was clear cut. So, this was a common theme and but now it is known as the Big Woods of the state.
And so a really good example of this is from Kappa Gamma and insolate in Minnesota.

So this is North Eastern Minnesota, commonly known as cab off its national lands, their state land, I forget, I think it's national stuff. But basically, this is the area of Hector's within this landscape from 1926 to 1986. It's over a 60 year period. And so why do you think it changed so much?
What changed?
What changed it so that was a massive shift in the landscape.
beavers are an ecosystem engineer. Maybe there was more beers in the system that that took it and shifted it from all of this forested landscape. To more moist Meadow wet Meadow can be repurposed.

So, why why do you think beaver levels were so low that you wouldn't have had many beaver ponds.
beavers were trapped really heavily. They were, you know, extirpated in some areas. You know, beaver numbers, they just been trapped for a long time really heavily. And so, you know, beavers now are really common. In some places. They're they're considered at nuisance levels. from a human perspective, they're their nuisance levels. But that wasn't always the case like they had to be reintroduced in South Carolina, I think in the 1940s. They they're just gone. So here, it doesn't look like they are gone in Minnesota, but their numbers were much, much lower. And they have you know, beaver numbers are high now.

So because there are more beavers and more beaver ponds created, basically changed from a mostly forested area to a mix of these meadows and woodlands. And this is also a change, you know, changes in nutrient retention, basically, look at how beavers have caused these nutrients to be retained in landscape. And just because of how they have altered it, to shifting from dominated by forest by to a mix of Beaver pond and in meadow and forest.
Alright, so if we're looking at this slide here, then and we've talked about matrices and patches, we can see these are from six counties in Ohio.

And so the dark green is these are forested patches, and it's surrounded by deforested lands. So forested paths are areas of patches, and we have this deforested land surrounding it in these six counties, right.

So by yourself, trying to do this by hand with paper and pencil, this would be really tough to, you know, figure out, you know, what is the you know, what is the actual percent you could get some guesses of deforested versus forested land. And the counties, you could guess is another interesting piece of information would be, what is the average path size, and we might want to know, what the average path sizes is, because different animals sometimes require different patches, some animals, small body animals and stuff, they can do really well in a small patch, they don't need a large patch, like a force, but other animals were talking you know, at the extreme talking about grizzly bears, one of their limits to to being in places besides you know, the social aspects of things and people not liking predators, is they need large roads with roadless regions, these big giant patches that are rare now, you know, on the landscape.

So, you know, thinking about here, the patch sizes here, versus the the average patch size here and on that all that type of stuff is the power GS can be quantified using, you know, Spatial Analyst tools within GIS.
Alright, so we left off here, read mode pointer up here. And we left off talking about memories maps here. And then using like geographic information system to actually quantify this stuff, how much forest and how much, you know, farmland would be or fear the, the, you know, here, for example, the farmland is the matrix matrix is that the area surrounding the forest is weather is the patches here, remember that.

And we can go back in and look at stuff like for each of these counties, you know, the total area covered, you could just, you know, trying to do this by hand to calculate it out. Not easy. But in something like GIS, you can do that, pretty easily.

We can also do things like calculate patch shape, right? And patch shape is important for a variety of reasons. And this, this is often quantified with this equation, where S is a perfect circle. So s equals one. And patches circular is sh s gets greater, it's less circular, circular, and there's a longer perimeter relative to the area. So there's more of a perimeter compared to the area that is within it, the ratio of that. And so this can be important, because if you think about it, some animals need lots of cornering.

And I mentioned this before, so something like a grizzly bear, they need large expanses of core habitat, know, where, where is their best habitat, because when you're thinking about patches, to go back up here, right, you have a patch and, you know, the outside of a forest as it borders, you know, a field, you know, that that first part of the force isn't really truly just forest, right? It's edge. So patches that are really long have a lot of edge habitat, but they might not have much core habitat and some species really need that core habitat that's really truly forest because you think about for the example you know, maybe within the forest a little more shaded a little cooler or something right on the edge, there's a little more sunlight you know, so they're these they're these differences both a biotic and biotic differences between the edge and the core of the habitat.
So patch shape effects how much edge there are edge there is right with if this number is larger, S is larger, there's going to be more edge relative to what's inside of the patch.

And there's something known as the edge effect and this is this transitions and, and a lot of times edges they'll support a mix of species from from both habitats in some animals do really well in edge habitats.

Some animals do really well in edge habitats, you know, for example, well you tell me what types of animals might do well on edge having at Wake Forest in agriculture Come on, what types of critters
wouldn't be that small speak smaller species like mice, like rodents, like like
that or know that it could be I don't know for sure that I mean, that can make sense.

But think about deer, deer thrive in patchwork habitat. Now, that's probably why There's more deer in the continental US than there ever has been.

Coyotes do really well. And habitat, rabbits do really well in edge habitat, there are certain birds that do really well in edge habitat.

So sometimes edge habitat can have like really high species richness compared to the core, or the matrix. You know, surrounding it, because you get a mixed species in some species just do really well on the edge. Right.

But you know, it when you're thinking about these habits, from a conservation perspective, say you're evaluating four different pieces, you're working for the Nature Conservancy, you're evaluating four different pieces of land in South Carolina to buy. And there are certain target species you're focused in on. And this suit, let's assume none of them are hit edge habitat specialists. You would want to look at, you know, maybe the reach 100 acres, but 100 acres isn't just 108. And one of the factors you might want to consider is what is the patch shape, how much core habitat is actually there?
So this is for something totally different looking at butterflies and skin others they they looked at the effects of patch eyes or in the population size and density of these butterflies. The Granville Granville, fertility flies, so here we have our population size on the x axis, the area squared and meter squared on the y axis.

These are different patch sizes so each dot represents a different patch size. So each point as okay this is saying is a scatterplot x Access, maybe about 11 acres and population size. This is on a log scale here. So population size of maybe like 60 individuals over here is density. So number of individuals per meter square, and area and so you have an inverse relationship.

So as patch size increases, the number of butterflies living the patch into some bigger patch, not surprisingly, holds more butterflies.

But the number of butterflies crammed into that area is not as much they spaced out more, so the density decreases as the patch size increases, right.

And they looked at this across like, you know, some pretty substantially different sized patches from 12 meters squared to 46,000 meters. And the distance between these patches ranged from somewhere just 30 meters apart somewhere over a kilometer and a half apart. And they also found that the the isolated patches supported lower densities of, of butterflies, this is probably because you're not getting immigration into that. So if they're more isolated, if they're farther away, you're not getting butterflies coming in from from other areas.
So we have packsize patch shaped it's important distance between patches is important. And distance between patches, you know, I kind of briefly just touched on that. But that can be a really important within a species for like the life stages. Because, you know, animals, sometimes early in life require, you know, some sort of habitat.

But then as they get bigger, they require a little different habitat. And then as they become adults, they require a little different habitat.

And so having connection between those habitats is is really important as well. Another so and that falls in line with this, this concept of habitat corridors, these connections between patches.

In some species, just their behavior restricts movement between unconnected unconnected patches. We saw this with like copperheads on campus, when I helped Megan Novak to a study she was wanting Dr. Parker's graduate students and I was on our committee. You know, they did it seem the copperheads they didn't seem to really venture into other patches that much the kind of stayed in their own little woods, even though we always think of snakes is it I've seen him on the road or did it on the road. That seemed to be like, a more unusual thing, right? At least on campus.

But you know, so some species just don't like moving between batches. So save, save. If they have to cross a really big open area to get to a patch, and that exposes them, they don't like doing that. It's they won't do it. You know, it also has risks, you know, because of collision with vehicles, sometimes to disconnection patches.

And in some ways, there's been there's been quite a bit of work on this though. And sometimes for some species, the issue isn't as far as when it comes from an abundance thing.

Abundance perspective, if you cut roads between two patches, the abundance is any abundance that loss isn't necessarily lost because of this connectivity, though, might actually be lost just because of the habitat that is lost by cutting the road.

So your loss of habitat, but for some species, they just don't like moving across things like open areas. A dot and bomb, they looked at some butterflies again, and they found higher densities of butterflies in connected patches compared to disconnected patches was about two times higher, you know where they could move between these areas of of habitat. Right. So, habitat corridors are important. They're something that are, you know, considered a lot with planning. Making wildlife corridors, especially You know, we've fragmented landscape we've broken up the landscape think about like, major highways are not a, you know, by by land area. You know, we think about a major highway going through someplace by land area. It's not like that much area.

But it can be a huge obstacle for no some No, it's a huge obstacle fleet and fast animals. I mean, think about deer again hit. They get whacked all the time bears, but there was one place in Orange County off of I think like 90 were it within I don't know how long the iceberg but they're like, close to 10 bears hit in one location over, you know, a several year timespan because it was because it was a you know, they followed a swamp, I think basically across the road there. But you know, so thinking about that type of stuff. In some places, they've come up with pretty inventive over highway habitat corridors where it's like, a bridge with net, a net with natural landscape features over top of the highway. I've seen some stuff like from Alberta with that, that's pretty expensive. But yeah, having corridors, both to allow connection between patches, and allow for safe connection between patches, so animals aren't colliding with vehicles and such.
And all these red lines are their movements, right? And she found the total distance moved in a straight line just as different between these two areas. But the snakes in this unfragmented environment. The only fragment was a dirt road, like a paved road or anything like a pretty unused dirt road. The only so that was the only fragmentation here. And basically, these snakes in the unfragmented Forest had a bigger occupied area.

So the snakes would use like it would move about the same total distance. But they would have bigger occupied areas. Their home range was larger in these more natural habitats. So they said they're comprehensive all over campus. Yeah, yep. We got copperheads right across from the Science Center. We got copper is by track we our copper is by baseball field, you know, all around actually I saw Unfortunately, there's a dig had copper had like a year and a half ago on the sidewalk walking into science to live look like he got hit by a lawn mower around my lawn.

But yeah, they they, you know, in these natural areas, they had a bigger occupied area, you'll notice that you know, one thing she observed, they did not like coming out in the open, right, they would stay in their wooded patches. They did not want to venture into this, why students don't really Sam and Sam. In general, they don't like they're not going to be in the middle of the quad. You know, they don't like going into these more open areas because it's dangerous. Right? They stick to their smaller patches.
Okay, so switching gears, then think about one thing. So we talked about patch shape and patch size and patch distribution and habitat connectivity and something you know,

...another huge, huge, huge field, especially in a flag system, or product road is looking at how land use affects aquatic systems through things like water, transport, sediment transport, nutrient transport.

So those of you that are in South Carolina, it for two nights ago, it poured last night. So think about the rain, then moving off and across the landscape. How does rain moving across the landscape differ from this top left picture to this middle picture to this bottom right picture?
On the in the center one, it's moving across the zone that I don't think is really built for holding much wires. So it's spraying a lot of sediments and material with it.
Yes, bring in lots of sediments material. Yeah,
that's a very disruptive rain. Well, very far right seems to be more of a stream that is used to lots of water going through it. And very far left seems to be a man may industrial zones. So it's built for channeling water.

So in saving the agricultural zone, in agricultural areas, you're going to get water off landscape a lot, you know, if there's too much of it. But you're basically when you clear land, think about woods, riparian areas, those, those are sponges, right, they slow the flow of water going into a system.

So if you think about a whole bunch of little streams draining into a bigger river, and, and maybe it's three different rivers, one river has a whole bunch of this paved surface, one river has a whole bunch of this air partial and one river is mostly forested, right, these two, the water is going to flow across the landscape a lot faster, and a flow across that sidewalk and you know, flow across the streets really rapidly, it's not soaking in as much you know, even more so than here, you know, the field it'll soak in a little bit, but rush up here, it's also going to carry a huge sediment load compared to here where you have these trees and everything that are that are filters in you know, a sponge in in here, you're going to get lots of nutrients being transported, if there's like fertilizer on the field or something then here think about all the stuff that might be on the street that can wash it to to the stream system.

So, you know, one thing that can be used is if you can be thinking about GIS and geographic information systems and looking at water, you know different watersheds and pervious surfaces and different types of land use in them. You can you can think about how that can affect water quality, right because as you as you move away from this for it's either this or this it changes how water flows. Right. You know, rivers and streams are the gutters through which you know, water flows off the landscape. So, normally, you know this might, after heavy rain, this might slowly rise the stream might slowly rise. You get a heavy rain in an agricultural field with a ditch running through it, if it arise rapidly. Same with you know, an urban stream you know where it's just stormwater dumping into it's going to rise rapid What else does this do? What about a summary? Has that changed things? summary go ahead
I'm sorry, I think I'm getting the wrong concept here too gone
is this is this blacktop cold in the summer or warm or hot or burn your feet off hot
to burn your feet All right,
so so that you know changing the landscape can also influence temperature of streams and so think about this temperature has nice cool Brook flowing through the forest even if it's July shaded compared to this it's more open but the fields not as hot as you know blacktop that you can fry an egg on in South Carolina right. So it can really influence water temperature as well.
So, the landscape structure influences how energy and nutrients and materials go across the landscape, you know, like water sediment on site type stuff, we mentioned things like nitrogen and phosphorus used to fertilize used to fertilize soils for agricultural field.

So, you can you can see that ending up in water than right based off a different land use. So, this is from some some stream years, this is looking at runoff volume, in forested compared to urban are the white egg cruncher these hatches, right? And so they just use like, this is the average percent change per 100 acres of land covered. So, if you convert 100 hectares of land one way or the other, this is how this will change the runoff volume. You know, because remember, runoff is how much water is runoff the landscape that forced is a sponge. Right?

So if you increase urban or agricultural landscape by 100 actors, increasing runoff volume, five 5% if you change it to 100, Eric tears of forest, you know, you're decreasing it by 8%. Sediment not surprising, right? You I mean, you get set lots of sediment, Washington urban area has been in agriculture areas, big time increasing sediment load, forest area, big time decreasing sediment load.

And so you get these different, you know, with phosphorus and nitrogen as well. nitrogen, phosphorus increasing in urban agricultural areas, decreasing forested areas. Interestingly, a big in urban areas, a big potential source of nitrogen and phosphorus, and some other stuff like bacteria, is animal waste, actually, people's pet waste that's not picked up. They were actually the Orange County or Walker river waterkeeper I think was handing out at the one like one event I took my kids to a couple years ago handing out like, dog poop bags, right, because just dog waste is you know, actually they've done some studies showing that it's a pretty important source of some of this stuff in in urban areas. So pick up after dawn.
So this is from a famous study looking at the effects of land use on biological integrity, you know, percent wetland is percent wetland increased, not surprisingly, higher ipi scores mean better. So basically, and this is from my old masters advisor in Michigan, and then Nancy Roth wrote this paper in the 90s. But more forced higher idi score, which means better idi is indexed by biotic integrity. And this is basically just, this is based off of what types of critters were there.

You know, as far as macroinvertebrates because some Some macro invertebrates are, you know, they're they're not all bugs, but we'll just colloquially call them bugs in the stream. There are really tolerant to pollution, others are not and they need really high water quality. And so essentially just based off of that, you can you often assign, you can assign stream health, there are all these different things that can be used to assign stream health based off of what type of macroinvertebrates are found in the stream.

So lots of agriculture, you get a pretty strong negative relationship almost 50% the relationship between percent agriculture and i vi or 50% of
the variability in ipi score can be explained just by how much agriculture is in the landscape. About the same thing for forests, but inverse, you have more forest, better i vi school, a little less for wetlands where you have about 40% of the variation but still a lot of lot of variation.

And not surprisingly, the highest scores are where there's the greatest person or percent wetland urban was a little more mixed, right you know, only about 21% of the variation is explained and with with urban The interesting thing is is that group is urban but not an urban is equal, right, this could be urban with some like forced in buffer around it, or it could be urban with like, concrete jungle. But for these other ones, you know, agriculture forests, WETLAND, very, very clear, distinct relationships.
And when we're thinking about landscape ecology, you know, these processes that we're talking about can happen at different stages. So this, this whole study of landscape ecology, who had the landscape where a lot of times using maps and GIS, well, if we're looking at a map, we have to think about or whatever ecological environmental thing we're thinking about, what's the appropriate scale, we need to zone into just a specific, you know, one acre plot? Or should we be looking at 10s of 1000s of acres, right.

And I use, you know, this is this is from stream ecology, but but looking at this, like stream shading characteristics, that's, you know, something that is more of a local site.

So here are a whole bunch of different like, things like channel form, nutrient retention, sediment retention, effects of lanius on temperature, organic matter, inputs, habitat. So, you know, things like shading of a stream, that's a very local thing, are there trees, right at that site?

But if you're looking at something like nutrient retention, that's a much that's a larger scale thing like that you're like, so if you're talking about nutrients, are they being retained by the land? Or are they washing into a stream? That is something that is happening over a large area, right, it's not happening at this, like tiny little, you know, 10, by 10 foot plot that is happening over, you know, could be hundreds of acres, 1000s of acres, but a large area.

So, you know, that's something to think about, as well, you know, what scale is when you're thinking about landscape? ecology? is a ecological process occurring it is it occurring at this tiny little small scale? Or is it occurring at this really big scale? Right, like, you know, we're, you're talking about a matrix of, you know, farms in urban area, you know, across, you know, hundreds of square miles affecting something or even larger, or is it something that's just been influenced, like, stream shading at a site? Or their trees, they're not, you know, within like, 100 meters, stretch it back.
All right. That's it. That's ecology, principles of ecology.