Managing functional diversity for ecological and nutritional goals in Brazil

Collaborators: Anne Elise Stratton, University of Michigan; Jucinei Comin, Federal University of Santa Catarina; Charles Lamb, CEPAGRO, Santa Catarina, Brazil

Funding: NSF GRFP; Conservation, Food, and Health Foundation; Elizabeth Caroline Crosby Research Award, University of Michigan

Ecological approaches to food production, particularly strategic increases in plant functional diversity on farms, may generate a wide range of ecosystem services and improve nutritional quality of food crops. To date, however, limited research has assessed these multifunctional outcomes on working farms. This project, led by PhD student Anne Elise Stratton, is determining linkages between crop functional diversity, soil biological processes, and crop nutritional quality on 16 small-scale family farms in southern Brazil. Cover crops and intercrops that include legume species have large potential to impact soil fertility and food crop nutritional quality because legumes convert atmospheric nitrogen, a necessary plant nutrient and protein building block, into plant-available forms of nitrogen in soil.Legume cover crops and intercrops could improve crop nutrient and phytochemical composition through multiple mechanisms, but the specific linkages between management and crop quality are poorly understood. This project addresses two research questions: 1) How do legume cover crops and intercrops impact soil nutrient cycling processes, crop yield, and crop nutritional quality? And, 2) Do soil properties predict the effects of cover crops and intercrops across a gradient of low to high soil fertility? The farms span a gradient of soil properties and fertility levels because they vary in the length of time since transitioning to ecological management.

Together with an NGO partner in Santa Catarina, the Center for the Study and Promotion of Community Agriculture (Portuguese acronym: CEPAGRO), we received a grant from the Conservation, Food and Health Foundation to build a network of cover crop “resource hubs” and farm managers within a wider participatory certification system for agroecological produce, ultimately driving innovation in sustainable soil management in Santa Catarina. The outreach effort will train 15-20 farmers in best practices to manage cover crops for soil fertility through a participatory research project; institutionalize cover crops as part of the certification network’s farm management plans; and host a first annual cover crop management and soil fertility workshop at a resource hub as part of participatory certification in eastern Santa Catarina.