Markets are emerging to pay farmers to store more carbon in the soil by using improved agricultural practices. But flows of greenhouse gases into and out of soil are complex, and some scientists are questioning whether these efforts will actually help slow global warming, according to the Yale School of Forestry & Environmental Studies.

While passage last summer of the American Clean Energy and Security Act by the House of Representatives calls for establishing a cap-and-trade program to limit greenhouse gases, it’s expected to have a serious financial impact for farmers. However, the financial penalties will be much lower for continuous no-tillers.