黄土丘陵沟壑区作物生产潜力影响因素分析——以王家沟流域为例

Factors affecting crop productivity in loess hilly-gully area──taking Wangjiagou watershed as an example

针对黄土丘陵沟壑区土壤侵蚀非常严重、作物产量低而不稳以及农业生产力水平低下的特点 ,本文首先分析了近几年来王家沟流域不同种类和不同年份作物生产力变化的特征 ,然后在地理信息系统 (GIS)技术支持下 ,利用基于土壤侵蚀条件下的YIELD作物生产力模型并结合各作物的实际观测资料 ,从降雨量、气温等气象因素以及地膜覆盖、施肥、梯田等耕作措施两方面分析了该小流域作物生产力变化的原因 ,结果表明在气象因素 (大气降水 )和土壤侵蚀的共同影响下 ,土壤水分和养分的变化是影响该区域作物生产力变化的主要制约因素。

Crop productivity model research is an important means to study agricultural production, but the universally low adaptability of the model limited its popularization and application. Since Geographic Information System (GIS) owns powerful function of analyzing, processing,managing and visualizing spatial data, it has been widely used in agricultural production. The loess hilly-gully area is one of the most serious soil eroded areas in the world and serious soil erosion has made soil quality degrade and land productivity drop. Aiming at characters of serious soil erosion and low and unstable crop productivity, this paper firstly introduces crop production of Wangjiagou watershed in recent ten years. Then, supported by GIS and aided with crop productivity mode YIELD model, combining actual observation data of crops, it analyzes reasons accountable for changes in agricultural production from two aspects of meteorologicfactors (precipitation, temperature) and farming practices, mulching fertilizing and terracing. The result showed that changes of soil moisture and soil nutrient affected by precipitation and soil erosion are the main factors influencing changes in crop productivities.Effective tillage measures can greatly enhance level of soil water and soil nutrient and promote crop productivities.