ASABE Technical Library - Abstract

Abstract. Karst rocky desertification is a process of land desertification associated with human disturbance and one of the most serious eco-environmental problems that threaten the sustainable development of agriculture in southwestern China. One way of reducing the constraint is to practice conservation agriculture(CA). In this study, the effects of no tillage with straw cover (NT) and conventional tillage (CT) on soil properties and crop yields were investigated in karst regions, Southwest China. Results showed that the 2-year conservation agriculture increased soil moisture content by 3%, while decreased soil bulk density by 7% in the top 30cm compared with CT treatment. In 2014, within 0-30cm soil depth, total nitrogen under NT treatment were 5% higher than that under CT treatment. In 2015, the mean soil organic matter and available P were enhanced 12% and 13% in 0-30cm soil depth than that under CT, respectively. short-term NT significantly (P < 0.05) increased available N in the top 20 cm by 9% as compared to CT treatment. For the effect of conservation agriculture on maize yields, 2-year mean yields increased by 11% compared with CT treatment because of the improved soil physical and chemical properties. Therefore, these improvements in soil properties and maize yields are of considerable importance for food security and sustainable agriculture in the karst regions.