Altered precipitation patterns are predicted to accompany climate change and are likely to impact grassland soil communities and nutrient cycling processes, which are dependant to a large extent soil water content. While short-term responses of soil communities and nutrient cycling to changes in precipitation amounts and soil water availability have been documented, very few studies have examined the long-term effects of these changes. A long-term reciprocal transplant experiment, initiated in 1993, provides a unique opportunity to address the long term response of soil communities (e.g.

An outstanding question for snowmelt-dominated watersheds of the western US is the response of stream flow to changes in climate. We know little about mountain aquifers because they commonly involve structurally complicated rocks, extreme head gradients (ground slope angles 10-40°), and dramatically fluctuating recharge due to seasonal snow-melt. In general, the western United States is predicted to face warmer temperatures and more frequent and prolonged droughts, and we can expect to see a decrease in annual snowpack, earlier onset of snowmelt, and increased evaporation.

According to the latest IPCC report, global climate change models are predicting an increase in the variability and intensity of extreme weather events, such as drought, in semi-arid regions. Semi-arid grasslands, or shortgrass-steppe, are among the most responsive ecosystems to global climate change. Therefore it is critical to determine the underlying mechanisms of their responses to scenarios like drought and how these mechanisms vary across space and time.

Climate models predict that precipitation patterns will change in the coming decades, and in the U.S. Great Plains, the frequency and duration of summer droughts is predicted to increase. Because water is the most frequently limiting resource in arid and semi-arid systems, changes in water and nitrogen availability may cause linked carbon (C) and nitrogen (N) processes to become asynchronous, changing retention and loss patterns that control ecosystem function.

Climate change has the potential to alter the genetic diversity of plant populations with consequences for ecosystem function. In this study we addressed whether a long-term climate change manipulation has altered the genetic diversity of a dominant C4 grass, Andropogon gerardii, which contributes disproportionately to ecosystem productivity in the tallgrass prairie, using the Rainfall Manipulation Plots (RaMPs).

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.

Konza prairie contains over 550 vascular plant species, of which, only a few have been closely studied. Predicted impacts of climate change on the tallgrass prairie region increase the importance of understanding how native tallgrass prairie species are likely to respond to future changes in water availability and increased air temperatures. Understanding which traits are the best predictors of relative abundance along a continuum of water availability (well watered to water stressed) will aid in the prediction of plant community structure under altered temperature-precipitation regimes.

Human settlements in both arid lands and cities must, of necessity, alter hydrological regimes and geomorphology to provide clean, reliable drinking water, water for agriculture, and protection from flooding. Additionally, people also create substantial modifications to provide water for manufacturing, recreation, aesthetics, and sense of place. All of these practices can result in elimination or degradation of existing aquatic ecosystems, as well as creation of new ecosystems such as artificial lakes, stormwater retention basins, mitigation wetlands, groundwater recharge ponds, etc.

Regime shifts from grasslands to shrublands in arid and semiarid ecosystems are thought to be irreversible, similar to state changes in other systems. We analyze long-term data from the Jornada Basin LTER site to determine if a directional change in climate provides an opportunity to reverse this conversion in the Chihuahuan Desert. We compare historical dynamics based on 140 years of landscape change (1858-1998) with 18 years (1990-2007) of detailed ecosystem responses under a variable climate to predict future responses under either a directional increase or decrease in rainfall.