How do agricultural conservation practices affect water quality?

How do agricultural conservation practices affect water quality?

Aug. 11, 2014

A new modeling framework will help managers estimate the effects of land use change and agricultural conservation practices on water quality.

The soil and water assessment tool (SWAT), was developed by CHANS-Net members Irem Daloglu, Joan Iverson Nassauer and Rick Riolo, as well as Donald Scavia. All the scientists are at the University of Michigan.

An integrated social and ecological modeling framework – impacts of agricultural conservation practices on water quality,” was published in online preview of the most recent issue of Ecology and Society.

The SWAT synthesizes social, economic, and ecological aspects of landscape change to evaluate how different agricultural policy and land tenure scenarios and land management preferences affect landscape pattern and downstream water quality.

The researchers linked a stylized agent-based model of farmers’ conservation practice adoption decisions with a water quality model to simulate the water quality effects of changing land tenure dynamics and different policies for crop revenue insurance in lieu of commodity payments over 41 years, from 1970 to 2010, for a predominantly agricultural watershed of Lake Erie.

Results show that non-operator owner involvement in land management decisions yields the highest reduction in sediment and nutrient loads, and crop revenue insurance leads to more homogeneous farmer decisions and a slight increase in sediment and nutrient loads unless cross compliance with expanded conservation requirements is implemented.