Ecosystem services along a management gradient in Michigan (USA) cropping systems

To assess tradeoffs and synergies among different services provided by major ecosystems in agricultural landscapes, we examined agricultural yield, aboveground net primary productivity, global warming impact, soil quality, water conservation, water quality, and plant diversity in eight replicated ecosystems along a management intensity gradient on the same soil type in SW Michigan, USA. Ecosystems included four annual grain systems in a maize–soybean–wheat rotation, two perennial crops (alfalfa and hybrid poplar trees), an early successional community, and a late-successional deciduous forest. The annual grain systems included tilled and no-till treatments both managed with conventional chemical inputs; and reduced input and biologically based treatments both managed with tillage for weed control and leguminous winter cover crops for nitrogen. Radar diagrams illustrated the suite of services provided by each system. We found 13 significant interactions between ecosystem service indicators, seven being positive and six negative. Numerous trade-offs with grain yield were found, suggesting that by focusing on grain yield in these systems, land managers may be neglecting other ecosystem services. Management of nitrogen fertilizer, cover crops, and tillage (no-till) were particularly important determinants for the delivery of multiple ecosystem services.