赤峰市沙化土地结构与动态研究

Study on Structure and Dynamic of Desertification Land in Chifeng City

采用实地调查与遥感材料分析相结合的方法,根据沙化土地的固定情况、利用方式及沙化程度引入土地沙化程度指数,对赤峰市沙化土地结构及1994年至2004年10年间的沙化土地变化情况进行综合分析,结果表明:(1)赤峰市沙化土地总面积为1 914 982.6 hm2,占全市总面积的22.2%。有明显沙化趋势的土地1 029 690.3hm2,占全市总面积的11.9%。从固定情况分析,流动沙地占7.8%,半固定沙地占10.1%,固定沙地占80.5%,露沙地占0.5%,沙化耕地占1.1%。从利用方式来看,沙化耕地占1.1%,沙化林地占24.8%,沙化草地占65.8%,未利用沙化土地占8.3%。根据沙化程度,轻度沙化土地占46.4%,中度沙化土地占35.2%,重度沙化土地占10.1%,极重度沙化土地占8.3%。各旗县土地沙化程度指数变动幅度较大,红山区土地沙化程度指数为0,翁牛特旗为22.45。(2)1994年至2004年10年间,赤峰市沙化土地面积减少748 797.3 hm2,减少28.1%。固定沙地增加5.6%,半固定沙地减少47.4%,流动沙地减少24.8%,露沙地增加223.7%,沙化耕地减少96.7%。土地沙化程度指数下降23.2%,红山区下降最多为100%,已经没有沙化土地。克什克腾旗和翁牛特旗下降最少,分别下降4.8%和6.9%。

By using the method of combining the investigation and remote sensing date, base on the fixed situation, use manner, desertification degree and land desertification degree index of the desertification land, the structure and dynamics of desertification land in Chifeng city during 1994 and 2004 were studied comprehensively. It is show that total desertification land area and the land with obvious desertification trend is 1 914 982.6 hm^2 and 1 029 690.3 hm^2, 22.2% and 11.9% of the total area of Chifeng city respectively. From point of fixed situation, shifting sandy land, half-fixed sandy land, fixed sandy land, exposure sandy land and desertification cultivated land is 7.8% ,10.1% ,80.5% ,0.5% and 1.1% respectively. From point of use manner, desertification cultivated land, desertification forest land, desertification grassland and unused desertification land is 1.1%, 24.8%, 65.8% and 8.3% respectively. From point of desertification degree, light desertification land, middle desertification land, serious desertification land and super serious desertification land is 46.4%, 35.2%, 10.1% and 8.3% respectively. The land desertification degree index range of different counties varies greatly, Hongshan district is 0, Wengniute county is 22.45. During 1994 to 2004, the desertification land of Chifeng city reduce 748 797.3 hm^2, reduce 28.1%. Fixed sandy land increase 5.6%, half fixed sand reduce 47.4%, shifting sandy land reduce 24.8%, exposure sandy land increase 223.7 % and desertification cultivated land reduce 96.7N. The land desertification degree index reduce 23.20%, the most is 100 % which take placed in Hongshan district where no sandy land present now, and the lest is 4.8 % and 6.9 % which take placed in Keshiketeng county and Wengniute county.