Conservation Tillage and Crop Residue Mulching Rapidly Restored Soil Structure and Microbial Activity on Degraded Maize Fields in the Patzcuaro Watershed (Mexico)

摘要

A field experiment with seven soil management treatments was implemented in a degraded soil of the Patzcuaro Watershed in central Mexico to evaluate maize cropping with conventional tillage (CT), no-tillage under varying percentages of soil crop residue coverage (0%, 33%, 66% and 100%), and no-tillage under 33% of soil coverage together with planted leguminous species (Vicia sp. and Phaseolus vulgaris L.). The treatments of no-tillage under soil crop residue coverage were established in 1995 and the leguminous species were planted in 1998. Two years after planting leguminous species, the alternative management treatments had increased total organic carbon, biodegradable C fractions, such as water soluble C, water soluble carbohydrates and biomass C, and aggregate stability compared to CT treatment. The highest increase in aggregate stability was found in the no-tillage with 33% of soil crop residue coverage treatment (28% greater than CT treatment). In particular, the use of no-tillage, preserving a moderate amount of crop residue (33%) and planted leguminous species rapidly improved soil quality. Assayed conservation tillage practices can provide an alternative technology for carrying out a sustainable agriculture in the Patzcuaro watershed, which can be extrapolated to similar areas elsewhere.