阴山北部土地荒漠化与气候特征分析

内蒙古阴山北部地区地处农牧交错带,是土壤风蚀、土地荒漠化和区域环境恶化最严重的地区之一,低丘陵区平均土壤侵蚀面积占土地总面积的52.65%,高平原区平均土壤侵蚀面积占土地总面积的93.13%。影响土地荒漠化的因子很多,自然气候是很重要的影响因子,分析自然气候对土地荒漠化的影响十分有意义。以阴山北部7个旗县多年降水量、地温、风速、观测和对沙尘暴日数的记录资料为重要参考,以武川县、四子王旗地表土壤风蚀试验数据为基本依据,短尺度分析自然气候对土壤风蚀影响的结果表明,土壤风蚀具有十分明显的季节性特征,即冬、春季是土壤风蚀的重要时期,尤其春季是土地荒漠化的最强烈时期。得出阴山北部地区风蚀平均侵蚀模数与风速、沙尘暴日数呈正相关,与地温呈负相关,与降水量的关系较复杂。阴山北部轻度风蚀地区的自然气候变化有增强风蚀作用的趋势,需多加关注;而风蚀作用强烈地区,地温的升高有增强风蚀作用的趋势,但年降水量的增加,年平均风速的减小,有减弱风蚀作用的趋势,并且沙尘暴日数有下降的趋势,土地荒漠化有减缓的趋势。

Analysis on the Relationship Between Soil Desertffication and Character of Climate in the North of Inner Mongolia

North of Mount Yin of Inner Mongolia,in the farming-pastoral ecotone,is an area where soil erosion is very heavy,and more and more people pay attention to it.52.65% area of low hill regions and 93.13% area of high plain regions were destroyed by wind.There are many cases that lead to soil erosion.Nature climate is an important case.So,analysis the relationship between nature climate and soil desertification has important meanings.How nature climate affects wind erosion was analyzed based on seven towns' statistics data,including rainfall,ground-temperature,wind speed and data about wind erosion in Wu Chuan and SiZi Wang town.The wind erosion showed seasonal dynamics and was very serious in winter and spring,especially in spring.Average erosion modulus of wind erosion positively correlated with wind speed and days of sandstorms,and showed negative correlation with ground temperature,and had complex relationship with the amounts of rainfall.The climate changes in lighter wind erosion regions tended to make wind erosion heavier and should be paid more attention.In the heavier regions,ground-temperature rising could make wind erosion serious.Increased rainfall and decreased wind speed and soil-storm tended to lessen wind erosion.