长江流域资源与环境 >> 2013, Vol. 22 >> Issue (8): 1221-.

• 生态环境 • 上一篇    下一篇

汉江中游河谷平原植被指数时空变化及其与沙化土地动态的关联关系

陈 慧|杜 耘|肖 飞|王学雷|严 翼|李元征   

  1. (1.中国科学院测量与地球物理研究所|湖北 武汉 430077;2.湖北省环境与灾害监测评估重点实验室|湖北 武汉 430077;3.中国科学院大学|北京 100049 
  • 出版日期:2013-09-20

RELATIONSHIP BETWEEN TEMPORAL AND SPATIAL CHANGE OF VEGETATION INDEX AND DESERTIFICATION LAND DYNAMIC IN THE PLAIN AREA OF MIDDLE REACHES OF THE HANJIANG RIVER

CHEN Hui1,2,3|DU Yun1,2 |XIAO Fei1,2 | WANG Xuelei1,2|YAN Yi1,2,3|LI Yuanzheng1,2〖MZ)〗   

  1. (1.Institute of Geodesy and Geophysics, Chinese Academy of Sciences, Wuhan 430077, China;2.Key Laboratory for Environment and Disaster Monitoring and Evaluation of Hubei Province, Wuhan 430077, China;3. University of Chinese Academy of Sciences, Beijing 100049, China)
  • Online:2013-09-20

摘要:

针对沙化土地广泛分布的汉江中游河谷平原区,采用MODIS EVI数据分析2003~2011年区域植被状态时空变化,并据此探讨沙化土地的动态特征。利用时序植被指数统计分析,探讨研究区植被的总体变化规律;分析不同缓冲区植被指数的空间分布格局,反映了区域环境状况的空间差异以及由此而可能产生的土地利用格局的变化;并基于不同距离缓冲区的EVI时空差异对比分析,探讨沙化土地动态与植被变化的关联关系。研究表明,近9 a来汉江中游河谷平原区EVI呈明显上升趋势;随着离河流距离的逐渐增加,每千米范围内各年的年均EVI值均表现出先增大后减小的空间特征,并在距河3 km区域处EVI值达到最大;而EVI的时空差异,则体现了沙化土地的空间分布与动态特征

Abstract:

Remote sensing has the advantage of high temporal resolution and monitoring large scale environment,thus it has been widely used to monitor the dynamic status of desertification.The vegetation index extracted from remotely sensed image can be used for regional desertification assessment.The normalized difference vegetation index (NDVI),as a common vegetation index,has been widely used to quantitatively and qualitatively assess the desertification during the past 20 years.However,the soil background and atmospheric noise influenced the application of NDVI.The enhanced vegetation index (EVI) is developed to avoid the interference from soil backgrounds and atmosphere,thus may show efficiency in monitoring the desertification dynamism.The plain area in the middle reaches of the Hanjiang River,especially for the valley,is characterized by high coverage.Monitoring the desertification status with regular remote sensing data is difficult,although the desertification of this region is ubiquitous.In this study,the vegetation coverage changes of this region during 2003—2011 were investigated with the time series of MODIS EVI data.The dynamics of desertification decreased during this period,as the EVI increased gradually.The SouthtoNorth Water Diversion Project triggered the decline of groundwater level for middle reaches of the Hanjiang River,and this might facilitate the desertification.Furthermore,the impairment of the decline in groundwater on EVI was negatively correlated to the distance from river.In response,a large area of land afforesting has been initiated to prevent the land from deserting in Lao Hekou,Xiangfan and Zhongxiang since 1990.However,the improvement of this project on vegetable coverage has not been accessed yet.According to the distance from the river,the region investigated was assigned as 8 buffer zones with equal distance of 1 km and the associated characteristics were analyzed.There were pronounced spatial fluctuations for EVI in buffer regions of different distances.In 1—3 km buffer region,the mean value of annual EVI increased with the distance from the river,and reached the maximum value at 3 km.Whereas in 3—8 km buffer zone,the EVI value decreased gradually.Additionally,these changes could not be well explained by synchronized climate factors,such as mean monthly temperature or/and precipitations.However,the variations of EVI in temporal and spatial scale may be attributed to the innate physiological,chemical and biological differences in soil.In conclusion,EVI values of the plain area in the middle reaches of the Hanjiang River valley showed a conspicuous ascendant trend during the last nine years,suggesting the efficiency of afforestation against desertification.While the discrepancy of EVI in different spatial scales suggested that attentions should be paid to the innate features of soil and proceed from local reality conditions

No related articles found!
Viewed
Full text


Abstract

Cited

  Shared   
  Discussed   
[1] 张 政, 付融冰| 杨海真, 顾国维. 水量衡算条件下人工湿地对有机物的去除[J]. 长江流域资源与环境, 2007, 16(3): 363 .
[2] 许素芳,周寅康. 开发区土地利用的可持续性评价及实践研究——以芜湖经济技术开发区为例[J]. 长江流域资源与环境, 2006, 15(4): 453 -457 .
[3] 郝汉舟, 靳孟贵, 曹李靖, 谢先军. 模糊数学在水质综合评价中的应用[J]. 长江流域资源与环境, 2006, 15(Sup1): 83 -87 .
[4] 程 江,何 青,王元叶,刘 红,夏小明. 长江河口细颗粒泥沙絮凝体粒径的谱分析[J]. 长江流域资源与环境, 2005, 14(4): 460 -464 .
[5] 彭 建,景 娟,吴健生,蒋依依,张 源. 乡村产业结构评价——以云南省永胜县为例[J]. 长江流域资源与环境, 2005, 14(4): 413 .
[6] 蔡述明. 研究长江中游地区水资源开发利用的新成果[J]. 长江流域资源与环境, 2004, 13(1): 100 .
[7] 段学花 王兆印 余国安. 以底栖动物为指示物种对长江流域水生态进行评价[J]. 长江流域资源与环境, 2009, 18(3): 241 -247 .
[8] 王宏巍. 俄罗斯土壤污染防治立法研究及其对构建我国《土壤污染防治法》的启示[J]. 长江流域资源与环境, 2009, 18(4): 326 .
[9] 刘蓓蓓, 李凤英, 俞钦钦, 于洋, 毕军. 长江三角洲城市间环境公平性研究[J]. 长江流域资源与环境, 2009, 18(12): 1093 .
[10] 许妍, 高俊峰, 黄佳聪. 太湖湿地生态系统服务功能价值评估[J]. 长江流域资源与环境, 2010, 19(06): 646 .