Bryan L. Foster - US grants

0076064
Holt
Understanding the implications of patchiness and spatial dynamics is fundamental to many issues in ecology, including many applied problems. This is particularly true of habitat fragmentation, which is a dominant feature of global change. A long-term experiment on habitat fragmentation is underway in the prairie-forest ecotone of eastern Kansas aimed at examining the impact of fragmentation on secondary succession, defined broadly to include key consumer groups, as well as plant dynamics. The physical layout of the experiment (initiated in 1984) is an archipelago of habitat patches in a large mown field. During the first phases of the project, there wre dramatic patch size effects on the distribution of small mammals, but no overall effect of patch size on succession. By 1993, colonization of woody plants was beginning to accelerate. It was hypothesized that this would lead to patch size effects on succession. This hypothesis has been borne out: the rate of succession towards woody vegetation has increased with patch size and decreased with distance from woodland source pools. There has been corresponding succession and spatial shifts in the small mammal community, and small mammals have been shown to inflict considerable damage on woody seedlings. In 1998 there was a serendipitous emergence of 17-year periodical cicadas, which imposed high levels of damage, with more damage in large patches. Monitoring of plant and small mammal dynamics will continue to determine the persistence of patch size and distance effects on successional trajectories. Because a large number of individually marked woody samplings exists, the demographic consequences of succession on woody species can be characterized, including the potential impact of the cicada emergence event on sapling demography. This project is unique in that no experimental studies of succession exist in which patch size effects on plant and animal dynamics have been measured.

Understanding how local and regional processes balance to regulate species diversity is a fundamental goal in ecology. Our research will examine the relative significance of local-scale ecological interactions and species availability in governing relationships between grassland plant diversity, soil nutrient supply, and habitat productivity. We will conduct two factorial field experiments concurrently within a Kansas grassland. In experiment 1, we will directly manipulate soil nutrient supply and plant productivity by applying nitrogen and phosphorus fertilizers to field plots. We will manipulate species availability through the use of multi-species seed additions. In experiment 2, we will manipulate species availability via seed additions in plots arrayed across a natural grassland productivity gradient. With these complimentary approaches, we seek to test a set of predictions regarding: (1) how the pool of available colonists affects the relationship between plant diversity and productivity; (2) how nitrogen and phosphorus supply interact to influence the nature of the diversity-productivity relationship; and (3) how species availability influences rates and pathways of vegetation succession under different conditions of nutrient supply and productivity. We are seeking new insights into the organization of plant communities as well as an enhanced understanding of the processes governing the development of diversity-productivity patterns in grasslands.

A grant has been awarded to University of Kansas Field Station and Ecological Reserves (KSR) under the direction of Dr. Bryan Foster, to construct a multi-purpose building and modest visitor housing at KSR. The multi-purpose building will enhance the KSR environment in three inter-related areas: 1) research, 2) education, and 3) health and safety. Research space in the proposed building will provide a general-purpose laboratory, a laboratory for wet chemistry, and a commons space (library, station archives/reference materials, computer laboratory) for resident and visiting researchers. The multi-purpose building will provide a physical setting for scientists to undertake innovative research that addresses complex environmental issues. The multi-purpose building will also provide basic accommodations for resident and visiting users of the field station. Improvements include a dedicated kitchen area and ample restrooms/showers. Two small sleeping cabins will accommodate the demonstrated need for housing an ever-increasing use of KSR by visiting scientists and students. Collectively these improvements will provide flexibility to accommodate a wide range of current and future uses, and promote the wellbeing of users by providing a safe and efficient work environment.

KSR also supports an active program of teaching and outreach. Teaching initiatives have grown recently and the new multi-purpose building will allow groups of students and visitors to engage in instructional programs in a more appropriate environment. Educational initiatives at KSR reach students of all ages (K-12 short courses, undergraduate classes and individual research experiences [including the NSF program Research Experiences for Undergraduates], graduate research and education, and public workshops). KSR is actively involved in bringing underrepresented groups into science; in particular, faculty and students at Haskell Indian Nations University increasingly use our facilities. KSR also promotes science infrastructure by providing research facilities and archived data sets to scientists both in the region and nationally. Research results produced by these scientists are broadly distributed through the scientific literature, and by novel approaches of public outreach and internet dissemination. Finally, KSR research addresses many topics of societal concern; examples include spread of invasive species, ecosystem restoration, risk assessment of transgenic crops, and pesticide effects on aquatic communities.

Understanding factors that regulate the composition and diversity of communities is a key aim in ecology, but is also necessary to anticipate and mediate impacts of environmental change on ecosystems. A long-term field experiment will be established to investigate the role of seed availability, local ecological interactions and chance factors in governing the dynamics of grassland communities along gradients of nitrogen fertilization. Experimental communities will be planted to establish a variety of initial conditions with respect to species diversity, composition and abundance. Once established, these communities will be exposed to varying levels of nitrogen fertilization to evaluate the extent to which fates of species and changes in the community are predictable based upon functional traits and initial population sizes of species.

The project will contribute to understanding of community formation along gradients of nitrogen availability, but also yield information applicable to grassland management and restoration. This project will contribute to education and training of female graduate students and undergraduates from University of Kansas (KU) and Haskell Indian Nations University. Minority students will present at meetings of the Ecological Society and the Society for Advancement of Chicanos and Native Americans. The project will be integrated into an existing public outreach program run by the KU Field Station.

Understanding how local and regional processes interact to regulate the structure and functioning of ecological systems is crucial for predicting the influence of human activity on biodiversity and ecosystem sustainability. This project continues two long-term field experiments in Kansas grasslands investigating effects of soil fertility and seed availability on grassland community dynamics in response to disturbance. Both experiments manipulate soil nutrients through fertilization and employ multi-species seed additions to manipulate availability of species to sites undergoing succession. Experiment 1 involves manipulations of soil nitrogen and phosphorus to examine plant community development on abandoned agricultural land. Experiment 2 parallels Experiment 1 with manipulations of soil resources and seed availability, but does so in the context of hay management and prairie hay meadow restoration.

Results from these long-term experiments will yield basic insights into the assembly and functioning of plant communities while informing the conservation and restoration of grasslands, particularly with respect to native hay meadows which are important repositories of prairie diversity in eastern Kansas. The project will contribute to the development of the University of Kansas Field Station (KUFS), complement ongoing research at KUFS in grassland and restoration ecology, and will support the education and training of graduate, undergraduate and high school students.

Intellectual Merit: Understanding species coexistence continues to be a fundamental goal in ecology with direct relevance to applied fields such as biodiversity conservation, resource management and restoration. For the practitioner of prairie restoration, knowledge of the different modes of coexistence and their relative importance in developing prairies would be valuable for guiding restoration prescriptions pertaining to site preparation, planting methods, invasive species control and management of disturbance regimes. This project initiates a long-term manipulative field experiment in eastern Kansas designed to evaluate multiple modes of species coexistence and plant community development, including the contributions of niche differentiation, functional similarity of species, spatial structure and initial community states in regulating native species establishment, diversity and species turnover in developing prairie restorations.

Broader Impacts: The project will contribute to the development of the University of Kansas Field Station (KUFS) and complement ongoing research and education initiatives at KUFS in grassland ecology. The PI will continue to facilitate involvement of underrepresented groups through participation in KU student minority programs and provide training for two new PhD students. Undergraduates will participate as student hourly field assistants, KU independent study researchers and REU students. The project will also be utilized by students enrolled in KU Ecology courses and by AP Biology students at Lawrence High School.

The University of Kansas is awarded a grant to improve facilities at the University of Kansas Field Station (KUFS). The station provides opportunities for research and public education along the ecotone between the eastern deciduous forest and the tallgrass prairie biomes. Construction of the facilities under this award is part of a larger vision of the KUFS to be fulfilled incrementally, in which the station will attract a greater diversity of students and faculty members from around the globe to world-class facilities inspired by environmentally sound principles. The funds will be used to construct an experimental greenhouse-mesocosm-common garden facility that will support classical mesocosm research, using experimental test systems representing an intermediate step between small laboratory systems and the natural world, serve general ecology workspace needs, and provide the capacity for year-round plant care and propagation that does not currently exist at KUFS. In addition, storm shelters will be constructed for the growing community of site users, an important safety feature given the weather conditions found at KUFS. Enhancement of the facilities at KUFS will help satisfy four critical long-term objectives. First, it will improve the setting where individual-investigator research can explore ecological questions at multiple spatial scales and multiple levels of experimental control. Second, it will further facilitate multi-investigator, interdisciplinary research projects. Third, it will lay the groundwork for future expansions to incorporate significant energy efficiency and sustainability concepts. Fourth, it will augment KUFS? contributions to large-scale networks such as the National Ecological Observatory Network (http://neoninc.org) and the Knowledge Network for Biocomplexity (http://knb.ecoinformatics.org/index.jsp).

KUFS activities encompass a broad array of teaching, public outreach, and research programs, targeting populations ranging from university students to school children, as well as the general public. Research at KUFS has provided a broad base of knowledge about ecotonal ecosystems in the region, and has fostered the development of scores of students and researchers. The proposed facilities will aid in the development of the KUFS mission by 1) improving research infrastructure in a way that promotes linkages between ecological levels of organization (i.e. communities, populations, and ecosystems) and bridges spatial scales (i.e. laboratory, mesocosm, and field studies); and 2) providing an enhanced platform on which to base undergraduate and graduate education. Importantly, improved facilities will help KUFS serve as a link between regional and national-scale science and education. For more information about the station, please visit the website at http://www.kufs.ku.edu/.

The University of Kansas Field Station (KUFS; www.kufs.ku.edu) is awarded a grant to provide high-speed internet service to KUFS and connectivity to enhance general research/education facilities, data network partnerships, and ongoing researcher programs. Specifically, funds will be used to connect facilities and research installations at KUFS to the University of Kansas main campus (Lawrence, KS) via single-mode optical fiber (cable). This fiber connection provides the communications backbone for high-speed internet connectivity, and a link to campus networking and other resources. Capabilities enabled by this award represent one part of a larger vision for KUFS to be fulfilled incrementally, in which a greater number and diversity of students and researchers from around the globe are attracted to world-class facilities inspired by environmentally sound principles. KUFS provides opportunities for research and public education within the ecotone between the eastern deciduous forest and tallgrass prairie biomes. Enhanced connectivity at KUFS will help satisfy five objectives critical for realizing the KUFS long-range vision. First, it will improve the setting for individual-investigator research. Second, it will further facilitate multi-investigator, interdisciplinary research projects that require electronic connectivity to thrive. Third, it will provide a mechanism for innovative and interactive on-site teaching and outreach. Fourth, it will facilitate KUFS operations through the monitoring of energy dynamics of buildings and facilities, and will enhance security for research projects by allowing real-time monitoring. Lastly, it will augment KUFS' role as a node within large-scale networks (e.g., the National Ecological Observatory Network [NEON]; USDA Soil Climate Analysis Network; AmeriFlux; and other networks). The communications upgrades in this project were developed by professional engineers and designers and will be maintained by the KUFS as part of its ongoing facilities operations, and by its parent institution.

KUFS activities encompass a broad array of teaching, public outreach, and research programs, targeting populations ranging from university students to school children, as well as the general public. Research at KUFS has provided society with a broad base of knowledge about terrestrial and aquatic ecosystems in the region, and has fostered the development of scores of students and researchers. The proposed communications upgrades will aid in the development of the KUFS mission by 1) improving research infrastructure to enable access to real-time data for projects spanning multiple disciplines; and 2) providing an enhanced platform on which to base undergraduate and graduate education. Importantly, improved facilities will help KUFS serve as a link between regional and national-scale science and education. As NEON and other networks mature or emerge, KUFS' historic role as a provider of long-term data sets, and as an active player in developing new data sets critical for forecasting ecological change will be highlighted. Scientific publications and presentations are an obvious means of sharing information, but KUFS also supports such efforts as database development and the generation of remotely-sensed data and images for basic and applied research. These efforts create platforms on which a diverse group of investigators and educators can base their work.

The spatial heterogeneity of the physical environment within a given area may be the primary determinant of the coexistence of multiple species and consequent species diversity therein. However, organisms themselves can contribute to species coexistence through their own processes of variable reproduction and dispersal, through interactions such as competition, and through ways that different organisms modify their environment locally and increase heterogeneity. The balance of the roles of the external environment and the organisms themselves in determining coexistence and diversity of species is a largely open question in ecology. This project will use a novel field experiment to examine this question for a grassland system in Kansas. The experiment will manipulate environmental heterogeneity using soil mixtures and will introduce differences in the effects of organisms by planting different mixtures of species in different ways. A computer simulation model will complement the experiment to explore the details of various processes. This work will contribute to knowledge on the maintenance of species diversity in plant communities, which is valuable in managing natural and modified (in this case, rangeland) plant communities to maintain ecosystem services. The project also contributes to the development of the next generation of scientists through training of graduate and undergraduate students and a well-developed connection to a local high school that involves students in the research.

This research will examine the strengths of exogenous and endogenous spatial heterogeneity in mediating species coexistence and diversity in grassland communities. The exogenous spatial heterogeneity is taken here as the spatial heterogeneity in soils, and the endogenous heterogeneity is taken as the conditions created by spatial heterogeneity in response to dispersal limitation, demographic stochasticity, competitive interactions, and organism-environment feedbacks resulting in endogenous spatial structuring of populations and communities independent of underlying environment gradients. A novel experiment will compare mixed and unmixed soils in a block design. Seeds will be sown to vary species aggregation pattern and species pools (by functional and phylogenetic diversity). A smaller set of experiments will focus on plant-soil feedbacks. The experiments will be complemented by the development of a simulation model that can mimic the experimental design. The simulation will allow additional scales of heterogeneity to be considered. By combining experiments with models, the work will close a gap between theory and empirical work. The research will be extended to education through an associate scientist program involving a local high school students who will participate directly in data gathering and analysis. Graduate students will participate in training undergraduates and the high school students. The work will contribute to conservation through an understanding of the effects of plant community simplification.

Pollinators are key to the maintenance of Earth's biodiversity because almost 90% of flowering plants rely on animal pollinators to reproduce. Pollinators are also a vital component of global agriculture, and pollination services by insects are worth hundreds of billions of dollars annually. Given their importance, it is critical that we develop an understanding of how insect pollinator communities interact with plants across complex landscapes that are often heavily modified by humans. Researchers have recently begun using "network" approaches to study plant-pollinator interactions across entire ecological communities. A plant-pollinator network can be visualized as a "web" of all interactions between pollinators and plants at a given place. By building and evaluating plant-pollinator networks, researchers can, for example, assess whether pollination at a given site will remain stable in the face of disturbance or loss of species. This is especially relevant, considering that human-induced stressors, such as habitat loss and pesticide use, are causing pollinator declines worldwide. This research will use a new genetic approach to determine which plant species are pollinated by which bee species in ten Kansas prairies. Data will be used to construct plant-pollinator networks to assess the potential effect of disturbance and loss of pollinator species on pollination services across human-modified landscapes. As part of this project, the research team will conduct pollinator ecology workshops for middle- and high school students aspiring to be first-generation college graduates.

Plant-pollinator networks are typically constructed from observations of insects landing on flowers (i.e., "visitation networks"). Few researchers have evaluated these insects for the presence and species identities of pollen carried between flowers; doing so based on pollen morphology is especially time-consuming. In this project, investigators will use metabarcoding to identify pollen carried by native bees collected across ten study sites. Several structural properties of the resulting pollen transport networks will be compared to the properties of networks based on visitation data alone. Investigators predict that: A) pollen transport networks will exhibit greater network-level specialization than visitation networks, and B) pollen transport networks will be less nested than visitation networks, indicating that plant-pollinator interactions could be more susceptible to species loss than the visitation data, alone, would suggest.

Pollinators are key to the maintenance of Earth's biodiversity because almost 90% of flowering plants rely on animal pollinators to reproduce. Pollinators are also a vital component of global agriculture, and pollination services by insects are worth hundreds of billions of dollars annually. Given their importance, it is critical that we develop an understanding of how insect pollinator communities interact with plants across complex landscapes that are often heavily modified by humans. Researchers have recently begun using "network" approaches to study plant-pollinator interactions across entire ecological communities. A plant-pollinator network can be visualized as a "web" of all interactions between pollinators and plants at a given place. By building and evaluating plant-pollinator networks, researchers can, for example, assess whether pollination at a given site will remain stable in the face of disturbance or loss of species. This is especially relevant, considering that human-induced stressors, such as habitat loss and pesticide use, are causing pollinator declines worldwide. This research will use a new genetic approach to determine which plant species are pollinated by which bee species in ten Kansas prairies. Data will be used to construct plant-pollinator networks to assess the potential effect of disturbance and loss of pollinator species on pollination services across human-modified landscapes. As part of this project, the research team will conduct pollinator ecology workshops for middle- and high school students aspiring to be first-generation college graduates.

Plant-pollinator networks are typically constructed from observations of insects landing on flowers (i.e., "visitation networks"). Few researchers have evaluated these insects for the presence and species identities of pollen carried between flowers; doing so based on pollen morphology is especially time-consuming. In this project, investigators will use metabarcoding to identify pollen carried by native bees collected across ten study sites. Several structural properties of the resulting pollen transport networks will be compared to the properties of networks based on visitation data alone. Investigators predict that: A) pollen transport networks will exhibit greater network-level specialization than visitation networks, and B) pollen transport networks will be less nested than visitation networks, indicating that plant-pollinator interactions could be more susceptible to species loss than the visitation data, alone, would suggest.

Long-term studies are increasingly valuable as a means to evaluate and predict the responses of ecosystems to multiple global changes. This research program employs two long-term field experiments in Kansas grassland to evaluate the interplay of soil fertility, plant species interactions and regional processes governing the recovery of vegetation, biodiversity and ecosystem function on abandoned agricultural lands. Results from these long-term experiments will continue to yield basic insights into the dynamics and functioning of ecological communities following disturbance and in response to excess nutrients. The results will also inform the management, conservation and restoration of native grasslands. The project will continue to contribute to the development of the University of Kansas Field Station (KUFS), complement ongoing research at KUFS in grassland and restoration ecology, and support the education and training of graduate, undergraduate and high school students.

These long-term experiments involve the manipulation of soil nutrient availability via fertilization and employ multi-species propagule additions to evaluate the contribution of plant propagule availability in the regulation of plant community and ecosystem dynamics. Experiment 1 involves factorial manipulations of soil Nitrogen (N) and Phosphorus (P) and was established on a site that was plowed prior to the initiation of the study, permitting examination of plant community assembly in the context of secondary succession initiated on bare soil. Experiment 2 involves factorial manipulations of N and annual haying. This experiment parallels Experiment 1 with manipulations of soil resources and propagule pools, but does so with different initial conditions and in the context of hay management and prairie hay meadow restoration. Together these complementary experiments address a range of questions and hypotheses in community ecology emerging from six related themes that will continue to guide research: 1) species coexistence and diversity; 2) patterns and mechanisms of ecological succession; 3) community assembly and meta-community dynamics; 4) linkage between community structure and ecosystem function; 5) grassland restoration and management; 6) collaborative research in community and ecosystem ecology. Continued sampling of both experiments for another five years will extend the core data sets (plant species abundances and productivity data) to a 21-year time series and permit comprehensive syntheses of vegetation dynamics over two-decades.

Grasslands comprise 26% of global land area and 80% of agriculturally productive land. In addition to their agricultural importance, grasslands also play key roles in diverse ecosystem services, including the production of clean water and the prevention of flooding. Native grasslands are often very species-rich, with richness increasing with increasing annual precipitation and declining following disturbance. These patterns of diversity can have important consequences because species-rich grasslands have been shown to be more productive and more resilient to unpredictable events like drought, flooding, or tornado damage. It is essential to understand the processes that govern both the patterns of plant diversity and the benefits of plant diversity to better manage grassland areas. The different processes that create and maintain the rich diversity of plant species coexisting in grasslands are unknown, but recent research suggests that plant pathogens may play a role. This project examines the extent plant disease determines natural patterns of plant diversity within grasslands by conducting parallel experiments at multiple field sites within the United States and China. Undergraduates, graduate students and post-doctoral researchers will be trained in diverse field and laboratory methods, including students and faculty from colleges and community colleges adjacent to study sites in Illinois, Missouri and Kansas. Data from this project will generate new directions for the management of rangelands and also lead to improvements in the yield and resilience of agricultural and native ecosystems.

Pathogens are predicted to accumulate and limit plant productivity most strongly in grasslands with low plant phylogenetic diversity, low plant genetic diversity and high precipitation. These predictions will be tested through a coordinated set of field observations, field manipulations, and greenhouse assays, performed on parallel diversity and rainfall gradients in North American and Asian grasslands. Specifically, patterns of plant and pathogen phylogenetic diversity, patterns of plant resistance due to genetic diversity, and patterns of ecological and evolutionary feedback will be tested across rainfall gradients in central United States and China. Rainfall manipulations of experimental plant communities will test environmental dependence of plant species coexistence, productivity benefits of plant diversity, and the role of pathogens as drivers of these processes. These empirical studies will be integrated with mathematical models to generate predictions of patterns and benefits of plant biodiversity, as well as predictions of vulnerabilities of grasslands to environmental perturbations.