Soil Quality and the Solar Corridor Crop System

Abstract

e solar corridor crop system (SCCS) is designed for improved crop productivity based on highly e cient use of solar radiation by integrating row crops with drilled or solid-seeded crops in broad strips (corridors) that also facilitate establishment of cover crops for year-round soil cover. e SCCS is an agroecosystem with diverse system structure that should inherently provide many features to build soil quality. Management strategies include reduced tillage, intercropping, and soil conservation through crop residue retention, which are associated with improved soil quality attributes of enhanced C and N content, e ective nutrient cycling, and high microbial activity. Our objective was to evaluate the e ect of SCCS in 76-and 152-cm (corridor) row widths on selected soil quality indicators as an assessment of soil quality during establishment of SCCS. Microbial activity, measured as soil glucosidase activity, was highest in rhizosphere soils planted to corn (Zea mays L.) hybrids at 74,000 plants ha -1 regardless of row width. However, soil glucosidase activity was strongly correlated (r 2 = 0.72) with active carbon (AC), and showed trends for increased contents in rows bordering the corridor.is suggested that increased carbon xation by plants at the wide row spacing due to greater exposure to solar radiation also increased carbon substrates released into the rhizosphere for microbial metabolism. e limited soil quality assessment conducted in this study demonstrated that an integrated cropping system represented by the SCCS o ers an e ective management system for maintaining crop production while promoting soil quality and soil conservation.

Leaf, plant, to canopy: A mechanistic study on aboveground plasticity and plant density within a maize–soybean intercrop system for the Midwest, USA

“…Historic yield trends of maize hybrids in the Midwest have been attributed to increasing population density and changes in belowground architecture may have had a more direct role than aboveground architecture (Hammer et al, 2009). Efforts to characterize belowground plasticity in modern maize hybrids may be more effective at improving the solar corridor intercrop system, which would complement the evidence that the scM maize system can promote soil quality (Kremer & Deichman, 2014a).…”

The Solar Corridor: A New Paradigm for Sustainable Crop Production

“…Although the primary focus of the SCPS is to improve grain yield of the main crop (i.e., maize), the inter-cropped species have important implications for soil conservation, fertility management, soil organic matter maintenance, pest suppression, and soil health [14]. Cover crop mixtures including legumes in intercrop combinations may serve as nitrogen fertilizer resources for the main crop and minimize chemical fertilizer inputs and their potential environmental impacts [1].…”

“…Such interactions may provide yield stability for the main crop because the crop mixture in the SCPS maximizes light capture and water and nutrient use, and thus a more efficient resource utilization strategy by limiting competition by weeds. Proper management of the complexity of an intercropping system such as the SCPS will accommodate the physical, biological, and ecological interactions between the crop components to maximize biomass and grain yields while contributing to essential ecological services including nutrient cycling, biological pest control, water and soil conservation, and soil health [14]. The keys to effective management in the SCPS is a. selection of maize hybrids responsive to the solar corridor planting arrangement to fully utilize radiation; and b. compatible inter-crop species that do not interfere with maize yet provide the benefits of a secondary crop in grain or forage yields or for soil improvement and conservation.…”

Introduction: The Solar Corridor Concept

“…Trials were limited to six corn hybrids grown on one soil series at one location; thus, subsequent field studies with a greater number of hybrid selections on a range of different soils are needed to further validate the SCCS for high yields in sustainable crop production. Evaluation of the SCCS for potential improvement in soil quality relative to corn monoculture was conducted in the field during 2011 and 2013 (Kremer and Deichman, 2014). It was hypothesized that greater interception of solar radiation by corn in the SCCS increases root exudation of C substrates, leading to enhanced rhizosphere microbial activity and subsequent nutrient cycling, plant growth promotion, and pathogen suppression, all of which are soil quality indicators.…”

“…It was hypothesized that greater interception of solar radiation by corn in the SCCS increases root exudation of C substrates, leading to enhanced rhizosphere microbial activity and subsequent nutrient cycling, plant growth promotion, and pathogen suppression, all of which are soil quality indicators. The SCCS increased labile soil organic C and enhanced microbial activity measured as soil glucosidase activity, suggesting that corn in SCCS and the crop in the corridor continuously contribute to soil quality throughout the year, which is often limited in conventional monoculture systems (Kremer and Deichman, 2014). Thus, in addition to a potential for similar to greater grain yields relative to monoculture, the SCCS may also serve as a strategy for maintaining or improving soil quality, a critical component of sustainable agriculture goals.…”