The temperate forests of eastern North America support high biodiversity and critical ecosystem functions while providing natural resources and cultural benefits to an expanding human population. The region is shaped by a legacy of landscape change: major shifts in climate, vegetation and disturbance at millennial time scales; extensive deforestation for agriculture in the 17th – 19th centuries; and abandonment of farmlands, natural reforestation and increasing urbanization through the mid-21st century.

The KBS LTER site is in a diverse, rural-to-semirural landscape typical of the U.S. Great Lakes and upper Midwest regions. Research at KBS asks how diverse plants, animals, and microbes in agricultural landscapes can contribute to farm productivity, environmental performance, and profitability. We study annual and perennial crops including corn, soybean, and wheat rotations, forage crops such as alfalfa, and biofuel crops such as poplars, switchgrass, and native successional communities.

Tropical environments are changing fast due to deforestation and regrowth, urbanization, climate change, and other forces. The consequences are immense for the whole array of ecosystem services people require. The Luquillo Long-Term Ecological Research Program (LUQ) is tackling these issues in Puerto Rico. LUQ began in 1988 and focused on natural disturbances (hurricanes, landslides, droughts, floods) and ecosystem response. That work revealed patterns of resistance and resilience to cycles of natural disturbance.

 The National Ecological Observatory Network (NEON) is a national-scale research platform for analyzing and understanding the impacts of climate change, land-use change, and invasive species on ecology. NEON features sensor networks and experiments, linked by advanced cyberinfrastructure to record and archive ecological data for at least 30 years. Using standardized protocols and an open data policy, NEON will gather essential data for developing the scientific understanding and theory required to manage ecological challenges.

Landscapes at the Sevilleta LTER site are dominated or codominated by two perennial grasses from different biomes, Bouteloua eriopoda (black grama) from the Chihuahuan Desert and B. gracilis (blue grama) from the shortgrass steppe, and the Chihuahuan Desert shrub Larrea tridentata (creosotebush). We used a long-term removal study to examine inter-specific interactions between these dominant species, and to determine which species would eventually dominate following the removal of the others.

Diverse plant litter mixtures frequently decompose substantially differently than expected, compared to the average of the individual component species. These strong “non-additive” effects constitute an important way in which biodiversity influences key components of below-ground ecosystem function like soil C and N cycling, and it remains unclear which plant traits drive diversity effects on soil C and N cycling.

Freshwater wetlands of the Florida Everglades are oligotrophic (water total phosphorus < 10 ug/L in unenriched marsh), with published values for average aboveground net primary productivity of sawgrass ranging from 255-606 g C m^-2 yr-¹ and periphyton from 17-10,371 g C m^-2 yr^-1. High temporal and spatial variability in these estimates, derived primarily by harvesting and small-scale gas exchange techniques, have been attributed to the underlying geology and hydrology of the landscape and phenology of dominant species.

The 2007 Regional report by the Intergovernmental Panel on Climate Change predicted that the central grassland region of North America is very likely to warm substantially during the twenty first century. Modelers are less certain about changes in the timing and amount of precipitation in the region. Our research examines how changes in plant available water will affect critical biological processes in the central grassland region of North America, specifically comparing a site at the Shortgrass Steppe LTER to a site on the mixed grass prairie near Hays, KS.

In tallgrass prairie, annual tiller recruitment occurs primarily from belowground meristems (bud bank) rather than from seed. Therefore, in this system bud banks regulate plant population and community dynamics to a greater extent than seed banks. Current models predict greater variability in precipitation, with larger events and longer dry spells between events for northeastern Kansas. We hypothesize that bud banks mediate plant community response to changing precipitation patterns by differential release of meristems from dormancy and changing the production of new meristems.