In this paper, the index systems of the agricultura drought and decrease percentage of grain crop are established. Th trend and influence of drought in the region is analyzed based o the 50 years (1951-2000) statistic...In this paper, the index systems of the agricultura drought and decrease percentage of grain crop are established. Th trend and influence of drought in the region is analyzed based o the 50 years (1951-2000) statistical data of precipitation and 5 years (1951–2002) agricultural drought of the region, includin five provinces: Shaanxi, Gansu, Ningxia, Qinghai and Xinjiang The result shows that the drought disaster is increasing and th most serious were in the 1970s and 1990s, and main agricultura drought is a great disaster incident. The regression prediction equa tion of drought and flood grades and agricultural drought area grades are set up by the harmonic wave method, and forecastin the drought will lighten during the first ten years of the 21s century.展开更多
基金National Society Science Foundation of China (Grant No. 08BZZ031) National Nature Science Foundation of China (Grant No.40471053, Grant No. 40501077)+1 种基金Key Lab Foundation of Shaanxi (Grant No. 04JS39)Key Foundation of Baoji University of Arts & Sciences (Grant No.ZK06111).
文摘In this paper, the index systems of the agricultura drought and decrease percentage of grain crop are established. Th trend and influence of drought in the region is analyzed based o the 50 years (1951-2000) statistical data of precipitation and 5 years (1951–2002) agricultural drought of the region, includin five provinces: Shaanxi, Gansu, Ningxia, Qinghai and Xinjiang The result shows that the drought disaster is increasing and th most serious were in the 1970s and 1990s, and main agricultura drought is a great disaster incident. The regression prediction equa tion of drought and flood grades and agricultural drought area grades are set up by the harmonic wave method, and forecastin the drought will lighten during the first ten years of the 21s century.
