基于GIS的若尔盖县2009-2014年沙化土地动态变化定量分析

Quantitative Analysis of Dynamic Changes of Desertification Land in Zoige County from 2009 to 2014 Based on GIS

利用2009年和2014年若尔盖县沙化监测数据、土壤数据等,以沙化监测区为研究区,在GIS技术的支持下,对若尔盖县沙化分布及动态变化进行定量分析,为沙化治理和生态环境建设的对策制定提供科学依据,同时基于GIS对研究区进行了沙化防治区划,为沙化治理提供更直观、更精准的判断和决策手段。主要研究结果有:(1)沙化图斑分布呈聚集分布,空间异质性明显;(2)监测图斑的沙化程度高值聚类明显,表明沙化程度高的图斑在空间上呈现聚集分布;(3)沙化趋势在向西北方向扩展,向黄河和黑河区域扩展趋势明显。在河道6km范围内包括了约70%的有明显沙化趋势的土地,以及60%的沙化土地;(4)两期沙化土地均以轻度沙地为主,说明若尔盖县土地沙化还处于初始阶段,正是沙化治理的有利时期;(5)将研究区划分为:重点防治区、一般防治区、普通防护区、潜在防护区,并提出了治理策略。

Based on the desertification monitoring data and soil data of Zoige county in 2009 and 2014,and with the support of GIS technology,the distribution and dynamic changes of desertification in Zoige county were quantitatively analyzed,which provided scientific basis for the countermeasures of desertification control and ecological environment construction.In addition based on GIS,the study area was divided into desertification prevention and control zones,which provided more intuitive and accurate judgment and decision-making means for desertification control.The main results were as follows:(1)The distribution of desertification patches was aggregated and the spatial heterogeneity was obvious;(2)The clustering of monitoring patches with high desertification degree was obvious,which indicated that the patches with high desertification degree were aggregated in space;(3)The desertification trend was expanding to the northwest,especially to the Yellow River and Heihe River.Within 6 km of the river channel,about 70%of the land with obvious desertification trend and 60%of the desertified land were included;(4)The desertification land in the two stages of was mainly light sandy land,which indicated that land desertification in Zoige county was still in the initial stage,which was a favorable period for desertification control;(5)The research area was divided into key control areas,general control areas,general protection areas and potential protection areas.Finally,the control strategies were put forward。