From the USDA's Natural Resources Conservation Service:
ACEP's agricultural land easements also support environmental quality, wildlife habitat, historic preservation and protection of open spaces. Native American tribes, state and local governments and non-governmental organizations that have farmland or grassland protection programs are eligible to partner with NRCS to purchase conservation easements.
Wetland reserve easements allow landowners to restore and protect habitat for wildlife on their lands, reduce damage from flooding, recharge groundwater and provide outdoor recreational and educational opportunities. Eligible landowners can choose to enroll in a permanent or 30-year easement. Tribal landowners have the option of enrolling in 30-year contracts as well.