基于RWEQ模型修正的土地沙化敏感性评价

(1.生态环境部南京环境科学研究所, 南京 210042; 2.南京信息工程大学 江苏省大气环境与装备技术协同创新中心, 南京 210044; 3.生态环境部卫星环境应用中心, 北京 100094; 4.辽宁省生态环境保护科技中心, 沈阳 110161)

土地沙化敏感性评价; 因子优化; 中国西北部; RWEQ模型

RWEQ-Based Assessment on Sensitivity of Land Desertification
HU Mengtian1, ZHANG Hui1,2, GAO Jixi3, QIU Kuanbiao1, WANG Yansong4, LYU Jiujun4, JU Changhua1

(1.Nanjing Institute of Environmental Sciences, ministry of Ecology and Environment, Nanjing 210042, China; 2.Jiangsu Collaborative Innovation Center of Atmospheric Environment Technology, Nanjing University of Information Science & Technology, Nanjing 210044, China; 3.Satellite Environment Center, ministry of Ecology and Environment, Beijing 100094, China; 4.Liaoning Science and Technology Center for Ecological and Environmental Protection, Shenyang 110161, China)

assessment of sensitivity of land to desertification; factor optimization; northwest China; RWEQ model

备注

中国西北部是土地沙化面积最大,发展最快,危害最为严重的地区,提高土地沙化敏感性评价结果精度对精确识别沙化敏感区、科学划定土地沙化敏感性生态保护红线、制定土地沙化防治对策具有重要意义。基于土壤风蚀修正模型对我国通用的土地沙化敏感性评价方法进行了修正,研究了土壤风蚀修正模型中的风力因子、土壤湿度2个因子分别代替通用土地沙化敏感性评价中的大风天数、干燥度指数2个因子的可行性,并采用通用土地沙化敏感性评价方法与本研究提出的修正土地沙化敏感性评价方法对我国西北部地区土地沙化敏感性进行了评价。结果 表明:(1)修正土地沙化敏感性评价方法中的土壤湿度因子、风力因子分别与通用土地沙化敏感性评价方法中的干燥度指数因子、大风天数因子在空间上具有较高的一致性,但在气象站点分布较少的区域,修正土地沙化敏感性评价方法中的土壤湿度和风力因子更能准确地刻画气候干湿状况和大风情况。(2)修正土地沙化敏感性评价方法的评价结果大大提高了通用土地沙化敏感性评价方法的评价结果精度,可为中国沙化敏感性精细化评估提供科学参考。

Northwestern China is the largest area of land affected by land desertification with fastest expanding, which causes a great loss to this region. It is of great significance to improve the classification accuracy of land sensitivity to desertification for the accurate identification of areas sensitivity to desertification, for the scientific delimitation of the land sensitivity to desertification ecological red lines and for formulating the control countermeasures of land desertification. In this paper, the wind erosion factor and soil moisture factor in revised wind erosion equation model were used to replace days on strong wind factor and climate dryness factor in the assessment of land sensitivity to desertification(general assessment of land sensitivity to desertification). And we assessed northwest China's land sensitivity to desertification by the revised wind erosion equation model based assessment of land sensitivity to desertification(modified assessment of land sensitivity to desertification)and general assessment of land sensitivity to desertification. The results show that:(1)the spatial distribution of soil moisture factor in modified assessment of land sensitivity to desertification is strongly coincided with that of the climate dryness factor in general assessment of land sensitivity to desertification, at the same time, the spatial distribution of wind erosion factor in modified assessment of land sensitivity to desertification is strongly coincided with that of the days on strong wind factor in general assessment of land sensitivity to desertification; but in the area where meteorological stations scarcely and unevenly distribute, the soil moisture factor and wind erosion factor can more accurately describe the degree of land dryness and wind intensity;(2)compared with general assessment of land sensitivity to desertification method, the results of the modified assessment of land sensitivity to desertification method in northwest China could obtain higher spatial accuracy and more reasonable spatial distribution; the modified assessment of land sensitivity to desertification method can provide support for spatial refinement assessment on land sensitivity to desertification in the future.