Walnut orchard planted with mustard
Creating Healthy Agroecosystems

The field of agroecology explores how the living ecosystems on farm fields can be stewarded to
benefit the environment, economy, and human health.


Our agroecology research strives to address major issues facing California agriculture

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  • Overdrafting groundwater in times of drought
  • Water pollution from fertilizer and pesticide runoff

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  • Smoke from agricultural burning
  • Dust from tillage, traffic, and harvest
  • Pesticide drift from spraying
  • Nitrous oxide emissions from fertilizer use

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  • Soil salinity issues for irrigated cropland
  • Soil erosion on agricultural land

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  • Reliance on non-renewable energy, especially petroleum

We study how agricultural ecosystems can be encouraged to thrive. Broadly, we work on:


Biodiversity above ground iconAbove-Ground Diversity

By growing a variety of crops or integrating crops and livestock on the same farm, farmers spread economic risk and are less susceptible to the radical price fluctuations associated with changes in supply and demand. Properly managed, research suggests diversity can also buffer a farm in a biological sense by suppressing weeds, pathogens, and pests and holding soil, nutrients, and water in place.


Biodiversity below groundManaging the Soil

A common philosophy among sustainable agriculture practitioners is that a "healthy" soil is a key component of sustainability: the soil is viewed as a fragile and living medium that must be protected and nurtured to ensure its long-term productivity and stability. Research indicates practices that improve soil health can benefit crop yields, nutrient-use efficiency, water quality, and carbon sequestration. 


Bag of fertilizer iconEfficient Use of Inputs

Many inputs and practices used by conventional farmers are also used in sustainable agriculture. Sustainable farmers, however, maximize reliance on natural, renewable, and on-farm inputs. The goal is to develop efficient, biological systems which do not need high levels of material inputs.