Habitat Restoration and Agricultural Production under Land Retirement

Current land retirement programs seek to address drainage management challenges in the western San Joaquin Valley of California using a willing seller strategy. In choosing between available parcels, the program managers focus primarily on the drainage mitigation potential of retiring each parcel of land. The results of 50-year groundwater simulations suggest that retirement of parcels already underlain by shallow groundwater produces the largest drain flow reduction. However, the managers also want this land to provide useful habitat for threatened terrestrial organisms. Using the depth of unsaturated material above a shallow water table as a proxy for habitat suitability, the model results reveal that only retirement of land that is currently well aerated and free from shallow groundwater will provide useful habitat in the long term. A secondary objective of land retirement is to minimize the negative local economic impact of removing a parcel from production. According to a productivity proxy drawn from model results, the retirement of land already overlying shallow groundwater will minimize the short-term productivity decline.