The effects of two organic manures on soil properties and crop yields on a temperate calcareous soil under a wheat–maize cropping system

Abstract

To improve soil fertility, efforts need to be made to increase soil organic matter content. Straw manure is considered another important management practice to maintain soil organic matter content. This study compared effects of two organic manures (straw and farmyard manure) on soil properties and crop yields in a crop rotation system under semi-arid conditions. Soil physical, chemical and biological characteristics were determined in the experiment. After 25 years cropping and fertilization, two organic manures significantly influenced soil properties and crop yields. Farmyard manure combined with chemical fertilizer management (M + NP) resulted in higher increase in SOC, available-N, available-P, and higher activities of protease, urease, and alkaline-phosphatase compared with those found under straw manure combined with chemical fertilizer management (S + NP). However, soil of straw treatment had higher levels of potential soil respiration, soil water retention, microbial biomass, soil porosity, invertase, catalase and lower bulk density than farmyard manure treatment. M + NP produced the highest crop yields at all treatments. Biochemical properties of both treatments were positively correlated with SOC and nutrient content. These results indicate that straw management positively affected soil physical, chemical and biochemical properties as manure treatment in calcareous soil. Adding straw manure, as a replacement of farmyard manure, could be a promising strategy on some soil physical and biological properties as compared to farmyard manure in calcareous soil.