Similar soil multifunctionality and function synergies, but with management trade-offs, in agricultural land covers

Abstract

Evaluating and monitoring the impact of management on soil quality requires understanding how cropping systems or land covers combine multiple practices, which may thereby improve some soil properties but negatively affect others. We assessed soil multifunctionality in the most common agricultural covers (avocado, blueberry, blackberry, and annual crops) and uncropped soil (forest) to explore soil degradation in a region of central Mexico that is undergoing a massive transformation from forests or low-medium intensity annual crops to intensively managed commodity crops for exportation. We measured indicators for carbon sequestration, nutrient supply, soil structuring, population regulation, nutrient cycling, water retention, and plant growth promotion functions in 56 sites. We examined the effects of management practices on specific soil functions, multifunctionality, and on the synergies or trade-offs among soil functions. Increasing intensity of management in export crops was expected to reduce soil multifunctionality and function synergies and increase function trade-offs. Contrary to our expectations of low soil multifunctionality in intensively managed land covers, all covers obtained similar multifunctionality values because their scores varied within single functions but did not consistently decrease or increase in any of the covers. Carbon sequestration, nutrient supply, plant growth promotion, and soil structuring showed synergies that seemed unaffected by management. Population regulation, nutrient cycling, and water retention did not show synergies and showed trade-offs associated with management. Maintaining the synergies by promoting positive cascading effects of carbon sequestration and reducing trade-offs by increasing biological activities supporting multiple functions seems necessary for preserving soil functions and positive function interactions.