The Conservation Reserve Program (CRP) helps landowners retire environmentally sensitive land from agricultural production to reestablish ecosystems, aiming to improve water quality, prevent soil erosion, and reduce loss of wildlife habitat. In 2021, the USDA Farm Service Agency (FSA) identified Monitoring, Assessment, and Evaluation (MAE) Projects to quantify CRP environmental benefits on water quality and quantity, wildlife, rural economies, and our climate within perennial grasses, tree plantings, and wetlands.  Ducks Unlimited and USGS are leading the project, in which our Clemson team partners with Kenyon College (Gambier, Ohio) to focus on the Glaciated Interior Plains, particularly Ohio, Indiana, and Michigan. The overarching objective is to increase the understanding of soil organic carbon (SOC) accumulation and greenhouse gas (GHG) exchange across a 15-state region in the Central United States representing 81% of CRP wetlands and >138 Major Land Resource Areas (MLRAs). Ultimately, findings will aid FSA in more precisely directing CRP initiatives towards climate-related goals, refining current models, and enhancing tools for conservation planning. 

Longleaf pine, a once-dominant tree species in the southeastern US from Virginia to Texas, has seen a decline, often replaced by loblolly pine plantations. Recognizing the importance of longleaf for ecosystem services such as wildlife habitat, biodiversity, carbon storage, and water resources, there is a growing interest in its restoration. Longleaf stands might also be more resilient to climate change compared to loblolly plantations.

Currently, we lack data and effective models to understand how longleaf and loblolly stands will respond to a changing climate across their geographical range. To address this gap, our project utilizes a network of eddy covariance towers that measure daily forest water use and carbon dioxide exchange. By assessing the sensitivity of these processes to short- and long-term climatic drivers, we aim to fill critical data gaps for both species, accounting for various soil and stand characteristics.

We will integrate data from our existing six sites with information from legacy sites and establish two new sites to enhance our understanding of how longleaf and loblolly stands respond to different climates. The collected data will help refine ecohydrological models, enabling us to predict water yield and forest carbon sequestration more accurately based on specific site conditions and climate drivers.

In summary, this project contributes to advancing scientific knowledge of the complex processes and interactions within longleaf and loblolly pine ecosystems. By refining models, we aim to provide valuable tools for land managers, helping them predict how these ecosystems will deliver essential services in the face of a changing climate.