Research Themes

Ecological factors governing existing and future patterns of biodiversity

An overarching requirement in biodiversity conservation research is understanding the relationship between ecosystem function (e.g., plant succession, trophic structure, hydrologic and nutrient cycles) and patterns of species richness and abundance (Schultze and Mooney, 1994). The importance of diversity to ecosystem function, and vice versa, led one recent reviewer to call 2002 the "year of the diversity - ecosystem function debate" (Cameron, 2002) . In NW Yunnan, with its heavily humanized landscapes, one also needs to understand how habitat area and fragmentation affect population and ecosystem processes, as well as how to predict the impact of future land use changes on ecosystem health.

Issue 1. Land use systems and sustaining native plant and animal species . A first step towards designing strategies for biodiversity preservation is to survey existing patterns of biodiversity and correlate these patterns with potential factors that impact biodiversity. To identify the effect of human development on biodiversity, surveys must distinguish human impacts from coincidental and confounding factors (Underwood, 1994) , and this requires comparisons among sites that differ in human impacts but are similar in other ways. The highly dissected terrain of Yunnan creates numerous replicate valley systems, and the heterogeneous advance of infrastructure (particularly roads) creates an ideal situation for comparative studies (Mensing et al ., 1998) . Fruitful specific avenues of research would be to investigate patterns of plant and animal diversity in valleys with contrasting adoption of new agricultural technologies, forestry practices, sewage treatment, industrial development, or other features of infrastructure. With our Chinese counterparts and international collaborators, we are selecting flagship organisms that can be monitored for lake and wetlands health, and wild lands conservation. The longitudinal and comparative surveys will be designed and performed by faculty trainers with extensive relevant experience in collaboration with Chinese colleagues and international collaborators Missouri Botanical Garden, International Crane Foundation, The Nature Conservancy).

Issue 2. Identifying the causes of loss of biodiversity. Whereas surveys provide broad hypotheses about the consequences of land-use changes on collections of species, numerous problems can only be addressed with detailed investigations of single species or groups of related species. Students will have a wide range of opportunities for focal species studies, and the faculty trainers (both from the UW-Madison and from China) have collectively a wide range of expertise that can guide students. For example, IGERT faculty, Drs. Karasov and Reed, already have a student (of Dr. Ji's) studying how land use changes effect the nutritional ecology of Yunnan snub-nosed monkeys, a species of sufficient concern that it is the center of a bioreserve program in Yunnan. Another faculty, Dr. Porter, has developed the mathematical tools to model animal landscapes (Porter et al., 2002). These microclimate-and-animal models, based on first-principles using GIS based topography, climate, and vegetation data, and simple animal properties, can identify where species habitat exists, and predict the impact of changes in land cover or climate on population densities.

Dr. Zhu, based on the knowledge of habitat requirements of some key endemic species is combining this information with GIS/Remote Sensing techniques under fuzzy logic to map the current spatial extents of these habitats and identify habitat "hotspots" that need to be maintained. The analysis will also indicate impending gaps that must be filled to meet the requirements of these endemic species as well as areas currently protected but that are of low efficacy in biodiversity and thus could be used for economic development (Zhu et al, 2001; Scott et al., 1993). Other areas of expertise represented by IGERT trainers include toxicology, metapopulation dynamics, biological control, forest management, and wetlands restoration.

Issue 3. Land-use and water resources. A critically important ecosystem function in NW Yunnan is the maintenance of water resources. Managing water resources involves clean water for drinking, agriculture and recreation (Wilson & Carpenter, 1999) ; water for hydroelectric power generation, irrigation and navigation; and flood prevention. Locally our focus will be on the ecohydrology (Zalewski, 1997) of lakes and wetlands, as well as both nonpoint sources (e.g. crop and livestock production) and point sources (e.g., tourist facilities, highway construction) of pollution. Our research scope will be at the watershed level (Cedfeldt et al . , 2000) , building on the experience of our trainers in wetland, agricultural, watershed and basin systems. Nationally, the impacts of changing land-use patterns in Yunnan have been blamed in the flooding of the Yangtze River (Abramovitz, 2001) and internationally, dams along the Upper Mekong are affecting fish catches throughout SE Asia.