Influences of different plastic film mulches on soil water use and yield of winter wheat in semiarid rain-fed region Research progress on ecological effects under the rotational tillage patternsin agricultural regions of China Spatiotemporal variation of fractional vegetation cover and remote sensing monitoring in the eastern agricultural region of Qinghai Province Classification and Diversity of Echinochloa in Paddy Fields of Main Agricultural Regions in China First-level agricultural region division and strategies for their sustainable develpment The Ecogeographical Distribution of Hippophae rhamnoides Subsp. sinensis and Its Phytogeographical Significance Agricultural resources superiority and characteristic agricultural industrialization in West China