中国地理科学 ›› 2017, Vol. 27 ›› Issue (5): 784-799.doi: 10.1007/s11769-017-0897-3

• 论文 • 上一篇    下一篇

A Method for Alpine Wetland Delineation and Features of Border:Zoigê Plateau, China

ZHENG Yaomin1, NIU Zhenguo1, GONG Peng2,3, LI Mengna1, HU Lile4, WANG Lei5, YANG Yuxiang6, GU Haijun7, MU Jinrong8, DOU Gejia8, XUE Hui8, WANG Lin8, LI Hua9, DOU Gejie10, DANG Zhicairang10   

  1. 1. State Key Laboratory of Remote Sensing Science, Institute of Remote Sensing and Digital Earth, Chinese Academy of Sciences, Beijing 100101, China;
    2. Ministry of Education Key Laboratory for Earth System Modeling, Center for Earth System Science, Institute for Global Change Studies, Tsinghua University, Beijing 100084, China;
    3. Joint Center for Global Change Studies, College of Global Change and Earth System Science(GCESS), Beijing Normal University, Beijing 100875, China;
    4. Chinese Research Academy of Environmental Sciences, Beijing 100012, China;
    5. World-Wide Fund for Nature(China), Beijing 100006, China;
    6. Wildlife Management Bureau of Gansu Province, Lanzhou 730050, China;
    7. Wetland Management Center of Sichuang Province, Chengdu 610081, China;
    8. Gansu Gahai-Zecha National Reserve Administration, Luqu County, Gansu Province 747200, China;
    9. Sichuan Zoigê Wetland National Reserve Administration, Zoigê County, Sichuang Province 624500, China;
    1
    0. Gansu First Meander of Yellow River National Reserve Administration, Maqu County, Gansu Province 747300, China
  • 收稿日期:2016-03-30 修回日期:2016-07-11 出版日期:2017-10-27 发布日期:2017-09-07
  • 通讯作者: NIU Zhenguo,E-mail:niuzg@radi.ac.cn;GONG Peng,E-mail:Penggong@mail.tsinghua.edu.cn E-mail:niuzg@radi.ac.cn;Penggong@mail.tsinghua.edu.cn
  • 基金资助:

    Under the auspices of National Natural Science Foundation of China (No.41201445,41103041),National Science and Technology Support Program (No.2012BAJ24B01),National High Technology Research and Development Program of China (No.2009AA12200307)

A Method for Alpine Wetland Delineation and Features of Border:Zoigê Plateau, China

ZHENG Yaomin1, NIU Zhenguo1, GONG Peng2,3, LI Mengna1, HU Lile4, WANG Lei5, YANG Yuxiang6, GU Haijun7, MU Jinrong8, DOU Gejia8, XUE Hui8, WANG Lin8, LI Hua9, DOU Gejie10, DANG Zhicairang10   

  1. 1. State Key Laboratory of Remote Sensing Science, Institute of Remote Sensing and Digital Earth, Chinese Academy of Sciences, Beijing 100101, China;
    2. Ministry of Education Key Laboratory for Earth System Modeling, Center for Earth System Science, Institute for Global Change Studies, Tsinghua University, Beijing 100084, China;
    3. Joint Center for Global Change Studies, College of Global Change and Earth System Science(GCESS), Beijing Normal University, Beijing 100875, China;
    4. Chinese Research Academy of Environmental Sciences, Beijing 100012, China;
    5. World-Wide Fund for Nature(China), Beijing 100006, China;
    6. Wildlife Management Bureau of Gansu Province, Lanzhou 730050, China;
    7. Wetland Management Center of Sichuang Province, Chengdu 610081, China;
    8. Gansu Gahai-Zecha National Reserve Administration, Luqu County, Gansu Province 747200, China;
    9. Sichuan Zoigê Wetland National Reserve Administration, Zoigê County, Sichuang Province 624500, China;
    1
    0. Gansu First Meander of Yellow River National Reserve Administration, Maqu County, Gansu Province 747300, China
  • Received:2016-03-30 Revised:2016-07-11 Online:2017-10-27 Published:2017-09-07
  • Contact: NIU Zhenguo,E-mail:niuzg@radi.ac.cn;GONG Peng,E-mail:Penggong@mail.tsinghua.edu.cn E-mail:niuzg@radi.ac.cn;Penggong@mail.tsinghua.edu.cn
  • Supported by:

    Under the auspices of National Natural Science Foundation of China (No.41201445,41103041),National Science and Technology Support Program (No.2012BAJ24B01),National High Technology Research and Development Program of China (No.2009AA12200307)

摘要:

Accurate wetland delineation is the basis of wetland definition and mapping, and is of great importance for wetland management and research. The Zoigê Plateau on the Qinghai-Tibet Plateau was used as a research site for research on alpine wetland delineation. Several studies have analyzed the spatiotemporal pattern and dynamics of these alpine wetlands, but none have addressed the issues of wetland boundaries. The objective of this work was to discriminate the upper boundaries of alpine wetlands by coupling ecological methods and satellite observations. The combination of Landsat 8 images and supervised classification was an effective method for rapid identification of alpine wetlands in the Zoigê Plateau. Wet meadow was relatively stable compared with hydric soils and wetland hydrology and could be used as a primary indicator for discriminating the upper boundaries of alpine wetlands. A slope of less than 4.5° could be used as the threshold value for wetland delineation. The normalized difference vegetation index (NDVI) in 434 field sites showed that a threshold value of 0.3 could distinguish grasslands from emergent marsh and wet meadow in September. The median normalized difference water index (NDWI) of emergent marsh remained more stable than that of wet meadow and grasslands during the period from September until July of the following year. The index of mean density in wet meadow zones was higher than the emergent and upland zones. Over twice the number of species occurred in the wet meadow zone compared with the emergent zone, and close to the value of upland zone. Alpine wetlands in the three reserves in 2014 covered 1175.19 km2 with a classification accuracy of 75.6%. The combination of ecological methods and remote sensing technology will play an important role in wetland delineation at medium and small scales. The correct differentiation between wet meadow and grasslands is the key to improving the accuracy of future wetland delineation.

关键词: alpine wetland delineation, ecological methods, remote sensing, Zoigê, Plateau

Abstract:

Accurate wetland delineation is the basis of wetland definition and mapping, and is of great importance for wetland management and research. The Zoigê Plateau on the Qinghai-Tibet Plateau was used as a research site for research on alpine wetland delineation. Several studies have analyzed the spatiotemporal pattern and dynamics of these alpine wetlands, but none have addressed the issues of wetland boundaries. The objective of this work was to discriminate the upper boundaries of alpine wetlands by coupling ecological methods and satellite observations. The combination of Landsat 8 images and supervised classification was an effective method for rapid identification of alpine wetlands in the Zoigê Plateau. Wet meadow was relatively stable compared with hydric soils and wetland hydrology and could be used as a primary indicator for discriminating the upper boundaries of alpine wetlands. A slope of less than 4.5° could be used as the threshold value for wetland delineation. The normalized difference vegetation index (NDVI) in 434 field sites showed that a threshold value of 0.3 could distinguish grasslands from emergent marsh and wet meadow in September. The median normalized difference water index (NDWI) of emergent marsh remained more stable than that of wet meadow and grasslands during the period from September until July of the following year. The index of mean density in wet meadow zones was higher than the emergent and upland zones. Over twice the number of species occurred in the wet meadow zone compared with the emergent zone, and close to the value of upland zone. Alpine wetlands in the three reserves in 2014 covered 1175.19 km2 with a classification accuracy of 75.6%. The combination of ecological methods and remote sensing technology will play an important role in wetland delineation at medium and small scales. The correct differentiation between wet meadow and grasslands is the key to improving the accuracy of future wetland delineation.

Key words: alpine wetland delineation, ecological methods, remote sensing, Zoigê, Plateau