Influence Of Climatic Change On The Agricultural Land Use At Bashang Of Zhangjiakou

The Effects of climate change on agricultural production are being paid attention to increasingly. Bashang of Zhangjiakou area, located in the middle of farming-pastoral ecotone in China, is sensitive to the climate change. The agricultural productivity is of poor level here. Types of agricultural land use vary and show an interlaced distribution pattern. Besides, agricultural land use was affected by climate change obviously. Bashang Guyuan County of Zhangjiakou is taken as an example in this study, from the perspective of the major climatic factors change, combined with changes in the structure of agriculture, to explore the impact of climate change on agricultural land use as well as to analyze the problems of land use in Bashang. And then, the appropriate optimization measures were proposed.In the aspect of temperature change, annual mean temperature in recent50years took on a significantly rising trend in Guyuan County, with an average annual temperature of heating rate of0.38℃/10a. Average temperature of the seasons also showed an upward trend. Rise in temperature of winter was the biggest, for0.50℃/10a; rise in temperature of winter is the smallest, for0.33℃/10a. The total amount of active accumulated temperature and effective accumulated temperature was increasing, especially increasing degree of active accumulated temperature is up to73℃/10a.In the precipitation change aspect, trend analysis was made separately to the two factors: precipitation in summers (June to August) near50years in Guyuan County and absolute value of variability of annual precipitation in Guyuan County. The results showed that precipitation was on the decline, and the increasing trend of absolute value of variability of annual precipitation was very significant, indicating that the interannual changes in precipitation increases of this area. Using "De Martonne" dryness calculation method to carry on the analysis to the Guyuan County arid condition over the years, it was discovered that the Guyuan County arid degree aggravates unceasingly.Based on statistical analysis of arable land, grassland, woodland, agricultural land in Guyuan County, especially the analysis on arable land use situation in the past30years, it was found that cultivated area in Guyuan County changed greatly. After the implementation of Cropland to Forest and Grassland project in2000, the cultivated land reduced sharply, but the proportion of irrigable land in arable land showed a fast-growing trend. Apart from the potato, planted area of other main crops was reduced, crop yield declining obviously.Some related agriculture departments in Guyuan County were visited; the residence investigation in three typical villages and towns were carried on; the topics concerning the climatic change and its influence on the local agricultural land use were inquired as well as discussed with the local villagers. Suitable areas of agriculture land in Guyuan County were divided according to summer precipitation records of all villages and towns in Guyuan County. Finally, agricultural land use was optimally adjusted, combined with the current situation of local agricultural land use and the results of field survey in Guyuan County.