Analysis on the Factors Influencing the Evolution of Desertification in Ningxia of China from 1999 to 2009

Abstract

With the desertification monitoring data in 1999,2004 and 2009 in Ningxia,we analyzed the evolution of the desertification and its influencing factors in Ningxia.The area of desertification land decreased from 3.2074×106 hm2 in 1999 to 2.8988×106 hm2 in 2009 and reversed obviously during 1999-2009.The area of wind-erosion desertification land decreased from 1.5191×106 hm2 in 1999 to 1.3458×106 hm2 in 2009,and the area of water-erosion desertification land reduced from 1.6572×106 hm2 in 1999 to 1.4897×106 hm2 in 2009,while the area of saline desertification land increased from 3.11×104 hm2 in 1999 to 6.33×104 hm2 in 2009.The area of severe and moderate desertification land decreased obviously from 1.0098×106 hm2 and 1.4270×106 hm2 respectively in 1999 to 2.757×105 hm2 and 1.3838×106 hm2 respectively in 2009,while the area of slight desertification land increased obviously from 7.10×105 hm2 in 1999 to 1.1708×106 hm2 in 2009,so desertification degree weakened obviously.In desertification regions,vegetation cover was improved further and vegetation coverage increased.Among the climate and human factors affecting the evolution trend of desertification,the reversion of desertification was influenced decisively by national policy,comprehensive development and utilization project,establishing and perfecting of various ecological protection measurement and mechanism,public participating in combating desertification,and so on.The negative effect produced by climate change was offset by the positive effect of these human factors.However,the reversion of desertification was slowed down to some extent by the population pressure,the human unreasonable activities in historical period,the inefficient utilization of water resources,and so on.These human factors are the unfavorable factors in combating desertification,which needed to be overcome in the prevention and control of desertification in Ningxia in the future.