How will anticipated changes in climate interact with grassland plant community composition and diversity to affect the performance of seedlings? We ask this question for two reasons. 1) If plant species are to track spatial shifts in the locations of suitable climatic conditions, plant species must invade communities by means of seedling establishment; more diverse plant communities have been shown to be less invasible, but it is not known how warming will interact with diversity to affect invasion.

The Luquillo Forest Dynamics Plot (LFDP) is a 16-ha long-term study plot in subtropical wet forest in the Luquillo Mountains of Puerto Rico. It is part of the Luquillo LTER and the Center for Tropical Science (CTFS) network of large tropical forest plots. Forests are often subject to multiple, compounded disturbances, representing both natural and human-induced processes. Our goal is to understand forest structure, diversity and dynamics, and to predict long-term changes resulting from interactions of past human land use and intermittent hurricane damage.

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).

High yielding perennial grasses, legumes, and grass/cereal hybrids are currently being investigated as potential alternative crops which could produce high yields of food or forage while also maintaining high levels of ecosystem services (lowered erosion, increased carbon sequestration, improved soil quality, and higher levels of pollinators and natural enemies as compared to annual systems). However, it is still unknown to what extent it will be possible to select perennial grasses and perennial grass/cereal hybrids for increased yield without jeopardizing the perennial life cycle.