Developing an adaptive management framework for promoting agroecosystem services through cover crops

Developing an adaptive management framework for promoting agroecosystem services through cover crops

Summary

Given the environmental impact of conventional agriculture and its vulnerability to increasingly extreme climate variation, it is necessary to explore and develop alternative, more environmentally sensitive and resilient agricultural systems. By relying more heavily on natural agroecosystem processes, or management practices that mimic these processes, we can establish progressively more resilient production systems. In order to do this, we must better understand the plant-environment feedbacks in agroecosystems and develop a framework for transferring this knowledge into effective management practices.
As we work to manage ecosystem processes with more precision in sustainable agriculture, cover crops are a key tool. Cover crops have been used extensively in the past, and are increasingly used today, especially in organic farming. The contribution of some cover crop species to certain ecosystem functions like increased soil nitrogen and weed suppression is understood, but the degree of impact each cover crop species has on a given ecosystem process is still uncertain. In order to successfully manage these important ecosystem functions, we must have a better understanding of the connection between a given function, the mechanisms affecting that function, and the functional traits regulating that mechanism. This proposal lays the foundation for a framework to identify and interpret the impact of cover crop species and mixtures on relevant ecosystem functions, which will eventually allow us to better manage cover crops for these services. Our initial focus will be on the functional traits relevant to biological nitrogen fixation and weed suppression in mixtures of leguminous and non-leguminous cover crops.
This project is still in the very early stages as we were notified of the award in August and our initial screening plots were established in September as planned.

Objectives/Performance Targets

While we are working towards all of the objectives, we are still in the build-up and preparation phase. We have established our screening plots with five cover crops, alone and in mixtures. These are all over wintering varieties (rye, two hairy vetch varieties, Austrian winter pea, and crimson clover), so the bulk of data collection and progress will happen in the spring. Please see the uploaded photos for an overview of the experiment area and some crimson clover seedlings in October.

• Experiment plot in early December frost
• Crimson Clover seedling in October

Accomplishments/Milestones

At this point in the project schedule we are screening different cover crop varieties to use in the first field season that is part of this grant, in summer 2013. Additionally, we are assessing the best means to measure different relevant traits for the ecosystem services of nitrogen fixation and weed suppression. In preparation for our planned farmer collaboration next season I have begun to talk to our farmer collaborators about their specific interests in the project and land availability.
I have processed the initial soil samples from before planting in September to use as the baseline soil nutrient data. We will have another set of soil samples and a set of plant tissue to analyze in the spring after the cover crop have been harvested and plowed under.
So far all these tasks have gone as planned.

Impacts and Contributions/Outcomes

Given the short time frame and overall schedule, I can’t identify any concrete impacts or contributions to sustainable agriculture at this point. I do think that my initial communication with several partner farmers may have stimulated thought and discussion about their most pressing cover crop question, which I expect will lead to more targeted goals and outcomes in the future. I fully expect to be able to accomplish the expected outcomes outlined in the initial grant application by the end of the grant periods.

Collaborators: