Long-term responses in different karst agricultural production systems to farm management and climate change: A comparative prefecture-scale study in Southwest China

Abstract

Rapid shifts have occurred in the agricultural production systems of the karst regions in Southwest China to meet increasing food demands. The responses of agricultural production vary under different degree of rocky desertification. However, the interactive effects of related driving factors on the food production sustainability of local crops are unknown. In this study, we quantified the impacts of seven key indicators—population, cropland area, multiple cropping index, irrigation area, fertilizer use, temperature and precipitation—on agricultural production in three rocky desertification grade regions from 1960 to 2011. We also classified these indicators into three categories: population, farm management and climate change. The results showed that farm management and population were the main drivers of increased food crop production, contributing 79.7% and 17%, respectively. In contrast, climate change had a limited influence on agricultural production. With increases in crop yield, the influences of some indicators were enhanced, and the negative impact on the environment was also increased; therefore, the sustainability of agricultural production systems could be adversely affected in the future. The agricultural production systems in mild rocky desertification areas (Zunyi) could meet the current food demands, while the areas with moderate and severe rocky desertification (Bijie and Qianxinan, respectively) are faced with substantial pressure. Although continuous improvements in agricultural production efficiency due to advances in modern science, technology and management have partly mitigated environmental pressure, rocky desertification poses a challenge to the sustainable development of agriculture in Southwest China. These findings provide a reference for adjusting farm management practices and climate change countermeasures in regions with different degrees of rocky desertification to achieve agricultural production sustainability in the future.