Potato cropping system management strategy impacts soil physical, chemical, and biological properties over time

Abstract

Soil health is essential for agricultural sustainability and environmental quality yet may be degraded by intensive cropping practices. Improved cropping systems and management practices may greatly enhance soil properties associated with soil heath. Four different potato cropping systems, designed to address specific management goals of soil conservation (SC), soil improvement (SI), disease suppression (DS), and a status quo standard rotation (SQ), along with a non-rotation (PP) control, were evaluated for their effects on soil physical, chemical, and biological properties in field trials in Maine, USA. The purpose of the study was to determine how and to what extent these different cropping system approaches and practices would affect soil properties. Cropping systems were established in 2004 and actively managed through 2010, with potato crops also planted in subsequent years (2011−12) to examine residual effects. Cropping system significantly affected many parameters associated with soil health, with effects generally increasing over time as well as having lasting residual effects. All rotations increased aggregate stability, water availability, microbial biomass C, and total C and N compared to no rotation (PP), and 3-yr systems (SI, SC, DS) increased aggregate stability relative to the 2-yr system (SQ). The 3-yr systems with reduced tillage (SI and SC) also increased water availability and reduced bulk density relative to the other systems. However, the SI system, which included yearly compost amendments, resulted in greater increases in total and particulate organic matter (POM) C and N, active C, microbial biomass C, water availability, CEC, concentrations of P, K, Ca, Mg, and S, and lower bulk density than all other rotations. Cropping systems that incorporate management practices such as increased rotation length and the use of cover crops, green manures, reduced tillage, and, particularly, organic amendments, can improve soil physical, chemical, and biological properties associated with soil health.