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Jack Stanford
Organization of Biological Field Stations (OBFS)

Biodiversity and Ecosystem Function:
Measuring and Contrasting
biological diversity in relation to
ecosystem functions and social processes
in large regional ecosystems

OBFS has 195 stations--that means that thereís at least one of our field stations in every state in the country except either No or So Dakota (and weíre working on that). But I donít think we have a presence or were involved at all in this "Framewor k" document [see Keynote Address] and I think we need to be involved in this. We are very excited about participating in this symposium because we think that our member stations represent a fantastic monitoring network across the country We represent rural and very involved field sites where the intensity of research varies quite a bit. But at every site data gathering is going on. So think of that OBFS network integrated with our big brothers the LTER program in a way that already does rep resent a large part of the environmental change monitoring across the country. Part of the problem we have (and NSF is helping with this) is our instrumental infrastructure. We are having a heluva time getting up on the Web. Some of our field sites donít even have computers so please keep this in mind. But donít disregard us because we come from states that have powerful senators!

Now I will talk about biodiversity in terms of our field stations and long-term data bases and how they might be contrasted and compared across the country. Unfortunately I have not had time to do that comparison so what I will do is tell you what is g oing on at my site and compare it to what I think is going on at other sites. Biodiversity is a complex subject and it can be looked at in a lot of ways. Distribution and abundance of animals is the essence of ecology. How we talk about biodiversity is co mplex. How we integrate humans is complex. In many respects it is uninteresting or unuseful if it is not attached to some kind of interpretation. In other words itís one thing to collar a bunch of animals and follow them around and say "they were the re, and they were here." Itís another thing to say "why" that is so, and what are they doing in that ecosystem. We have tried to incorporate this idea in what we call the Crown of the Continent Ecosystem in northern Montana and southern Bri tish Columbia with the greater Yellowstone area. We have a project going on right now that compares and contrasts those two areas. Embodied in all these comparisons is the very very important concept of environmental change and how that influences both hu man processes and the distribution and abundance of the animals that most of us are interested in. Talking about both population and genetic kinds of diversity. There are corollaries on the human side that relate to culture history and so on. So out there on the landscape in a given ecosystem there is a complicated and interactive process that is going on.

Between the human side and bio-physical side we are searching for metrix that will allow us to make predictions about ohow those two atrtributes will interact. One of the mettrix that are useful is the debt/equity ratio because it is turning out that peole do things on the landscape according to this. So we could have a long discussion on the metrics that link these two things. Iím not gonna do that Ė Iím going to instead try to focus on a few studies that have gone on at our field station and rememb er this is not an LTER site but an intensive, fairly well instrumented, long-history field station. Our station was established in 1899 and itís been gathering information all along. But we only came up on the Web in a meaningful way in the last six month s. Because of our rural location. Also those 195 field stations I mentioned Ė ours is one in about five that has a full-time data manager. So LTER is pretty well equiped, we are coming on line and the more we can interact with LTER to try to understand of these kinds of questions is really important.

So let me give you some sort of run-through of the work thatís going on at our station that articulates some of those questions. Now hereís something we are very proud of and most intensive research sites have this now Ė this is a digital output itís b een very carefully calibrated and you can see the edge of the line and believe me that was not easy! Going across US/Canadian boundaries took just about all our funds to get that far and what we have here is land cover types accurate to about 30 square me ters in satellite imagery. This is done by the Spatial Analysis Lab at the University of Montana that has collaborated with us there at the field station at Flathead Lake. What we see here is a complex mosaic of land cover and use types and what we are tr ying to do is overlay this with meaningful databases that describe the distribution and abundance of animals and plants and people in ways that are meaningful to society.

Let me start at sort of a patch size and work back to that landscape picture. And try to articulate some of the x-site comparisons that might be possible from data that might be possible from data similar to what we are gathering in our studies and wha t is being gathered elsewhere. Here you see a grizzly bear in Glacier Natl. park in one of the what we call high sub-alpine dry meadows. And we are in the process of trying to determine what role that bear plays in this system. It is one of the charismati c megafauna that is being collared and studied Ė weíre interested in not just what the bear is doing but what itís doing to the structure and plant distribution in these meadows because it digs and much of the patchiness in what you see across here is a c osequence of these bears rototilling the soil as they dig for lillies. Now Iím a limnologist and you might wonder why I started working on this well as we were working our way towards high alpine lakes we had to watch for grizzlies and I noticed they were digging and doing so in what appeared to be a very non-random fashion. And we have gone out now and quantified this over long terms in the different meadows and basically in a nutshell the bears are creating patches that overlay from year to year as they dig for the bulbs of glacier lillies which are high in carbohydrates and other food values. And if I were to put the last few years over here last year there was less digging because the huckleberry crop was particularly good. And the year before that Ė vice-versa. So basically whatís happened is the bears are disturbing about 17 percent or so of these meadows annually. I have a student in another session ĖSandy T____ [?-didnít catch last name] will show that part of the response in the plant community i nvolves nitrogen cycling. The bears are releasing a mineralization potential and this causes the glacier lilies to dominate the community. Thereís something like 27 vascular plants in these meadows and in the disturbed areas thereís a predominance of succ essional species whereas in the other areas the other species predominate. I would like to make some x-site comparisons for example with the Niwot site. They have glacier lilies there but no bears. There are gophers there but no bears. So hereís one examp le of how x-site comparisons could be made. And also something about the important species in the montaine environments of the west. And in a nutshell Ė basically the bears are randomizing those meadows in their continued disturbance effect and are essent ially farming the lilies. Might want to take a look at Sandyís paper later on to see the data in more detail.

So the bears are up there in the top of the altitudinal gradient during some times of the year. During others they are down in the floodplain surfaces like this one especially in the spring when they first come out of the den. So thereís a big altitudi nal gradient here. Now I would like to tell you a little about the differences between the patch-scale of the mountain meadow and the river bottom flood plain and talk about the complexities of habitat and the distribution and abundance of animals across these very complex flood plain surfaces that exist in this case between Glacier Park and the high country of the Bob Marshall Wilderness Complex. These are areas that the ungulates have to come down and use in the winter because there is too much snow up higher. Very complex successional stages created by annual flooding of rivers creating a very dynamic and active riparian zone. Across this floodplain surface we can identify a whole host of different habitats created by downwelling and upwelling of water as it either flows through the channel or penetrates the aluvium. The different kinds of ecotonal surfaces that exist between the aquatic and upland environments on these flood plains involve lots of studies going on around the country. So what does it m ean? If you look at a single day in August for example the temperatures in the environments in this mosaic varies from about 5 degrees all the way up to 29 degrees centigrade. And all these habitats are interconnected. So thereís a template that allows a great number of aquatic, semi-aquatic and even terrestrial species to co-exist. To give you a couple of examples: here we have a well in a spring brook where we are sampling to find out what sort of macroinvertebrates live in the ground water system. We h ave discovered this whole food web involving small salamanders as the top carnivores. Now these are stone flies and the gist of this is that there is a tremendous amount of biodiversity in the groundwater system that influence processes at the surface. An d if you look at floodplains vs. channel and river vs. spring brook habitats, you come up with a total of something like 400 macroinvertebrate species on this floodplain surface. 30 percent of these would be unknown if you werenít looking at the groundwat er system. Now Iíll contrast that with a constrained reach of the river, or an upstream reach and the numbers of species may be half that. Thatís why we talk about these floodplain surfaces as hot spots of biodiversity. Now look at this distribution of fi shes in the floodplain ponds vs. the spring brooks vs. the main channel. The numbers differ from day to night Ė if you go out at night you see more because they are little guys. They brood their little ones in the quiet off-main-stream channels. Now if yo u regulate rivers you take away these habitats and itís no wonder that salmon are declining in the Northwest when these habitats are interrupted or disconnected from the main channel.

Now if you jam this up to a larger scale you can easily identify critical areas for biodiversity. It turns out that a good share of those areas are in areas where there is no roading Ė which is an extremely important process that tends to allow exotics to come in and natives to then decline. For example the boreal toad- a rapidly declining species that prefers the floodplains. We think the floodplains act as nodes for this species, giving us a model to work from when determining conservation patterns, based on long-term datasets and a very clear understanding of landscape dynamics. This is a plot of alluvial reaches in the whole Flathead basin. You can see they are arrayed in a patch-like pattern at this scale. You can gen this same concept up for the entire river basin. Now we think that recovery of Columbia River salmon has got to be closely tied to restoration and reconnection of these floodplain surfaces. Particularly those that have many of the natural attributes left of an ecosystem concept on th ose surfaces.

We could have done a lot of contrasting of those sites looking at floodplain structure and function. Thereís an LTER site here in New Mexico where Manuel Molles, Cliff Dahm and others are doing floodplain work that is directly comparable to what we are seeing up there in Montana. That kind of activity would greatly promote our understanding.

Now letís talk about Flathead Lake and the processes that occur here. President Clinton and Vice President Gore were just at Lake Tahoe and one of the cross-site comparisons that has been very popular is comparing Flathead Lake to Lake Tahoe. This is o ne of the biggest natural lakes in the country and we are concerned about decreasing biodiversity as a result of increasing fertility by letting blue-green algae to dominate the water column. Exactly the same concerns at Lake Tahoe. There is a very profou nd seasonal nutrient response. As these algae that grow in the lake take the available nutrients that come through the lakeóif you have a long-term database and a long-term perspective, carefully quality-controlled database you get an understanding of how annual quality influences the kinds of processes that occurs in the plankton community. And these are the long-term data that we have here for primary production Ė if your were to plot Lake Tahoe on here it would be very much lower in the early years and now itís very high. So problems in Lake Tahoe related to human sources of nitrogen and phosphorus have really changed the relationship comparatively between the two lakes. We can get a lot of value from cross-site comparisons as to why that is the case.

Then comes the problem with exotic introductions and what sorts of influences that has on lake processes. I will end here by showing again the rather infamous slide that shows how the introduction of Mi____ _____ [didnít catch genus/species name] which ate all the large zooplankton in the lake and changed the distribution of salmon and eagles Ė with the salmon migrating up stream to spawn and the eagles feeding on them. Clearly as the foodweb changed the eagles and salmon disappeared from this system. So making these associations with the trophic responses at these sites is extremely important. For example there is very solid work going on with trophic dynamics at North Temperate Lakes LTER site and we can make cross-site comparisons there, as well. So Iíll conclude there and just end by reminding you that biodiversity is a complex subject --area matters, geo-spatial context matters, and time matters. And with the networks gathering similar kinds of data on biodiversity perhaps we can really begin to u nderstand how regional patterns are really being influenced by environmental change.