Effects of land cover change on evapotranspiration in the tropical Lancang-Mekong River Basin from 2001 to 2020

被引:0
|
作者
Chen H. [1 ,2 ]
Chen Y. [1 ,2 ]
Song Q. [1 ]
Montri S. [3 ,4 ]
Nuttapon K. [3 ]
Zhang J. [1 ]
机构
[1] CAS Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla
[2] Fujian Provincial Key Laboratory of Subtropical Resources and Environment, Fujian Normal University, Fuzhou
[3] Department of Highland Agriculture and Natural Resources, Faculty of Agriculture, Chiang Mai University, Chiang Mai
[4] Agriculture and Forestry Climate Change Research Center (AFCC), Faculty of Agriculture, Chiang Mai University, Chiang Mai
关键词
evapotranspiration; Lancang-Mekong River Basin; land use; water resource;
D O I
10.11975/j.issn.1002-6819.2022.22.012
中图分类号
学科分类号
摘要
Land cover types have changed dramatically in the tropics as human activity is ever increasing in recent years. These changes can cause great impacts on regional water security. Therefore, it is a high demand to accurately quantify the effect of land cover change on evapotranspiration (ET) for a better understanding of the mechanism of the water cycle under global warming. This study aims to investigate the effects of land cover change on the ET in the tropical Lancang-Mekong River Basin (LMRB) from 2001 to 2020. Firstly, the land cover data was reclassified and we corrected the unreasonable change types. The land cover product (MCD12Q1) was then evaluated using high spatial resolution images with Google Earth Pro. Secondly, the ET product (MOD16) was assessed using a total of 10 eddy covariance observation sites. Pearson's correlation coefficient (r), Root Mean Square Error (RMSE), Mean Absolute Error (MAE), and Mean Relative Percentage Error (MRPE) were also used to analyze the land cover changes and ET trends in this region. Finally, a dynamic analysis was developed to accurately quantify the effect of land cover changes on ET water consumption, where the impacts of climate change were excluded. The results show that: 1) The MCD12Q1 performed better with an overall accuracy beyond 82%, the forests and cropland of which were 90.5% and 89.4%, respectively. The RMSE values of MOD16 on the 8-day and monthly scales were only slightly larger than 1 mm/day. Therefore, the two products (land cover and ET) can be expected to analyze the ET changes in the study area. 2) The changing area accounted for 24.7% of the total. There was a degradation trend of the overall vegetation, where the conversion areas of the forest to shrubs and shrubs to cropland accounted for 61.2% of the changing area. 3) The trend analysis showed that there was an increasing average ET of 5 mm/a in the entire region. 4) A significant difference was observed in the annual average ET of each land cover type. Generally, the annual average ET of the forest was higher than that of shrubs, and the annual average ET of shrubs was higher than that of cropland. 5) The major types of land cover change caused a total decrease of 27.89 billion m3 of water consumption, whereas, climate change led to an increase of 19.10 billion m3 of ET water consumption. 6) Although there was a decrease of ET in the land cover change area, there was no significant influence of the land cover change area on the increasing ET. In general, the vegetation degradation resulted in a decrease in ET and water consumption, indicating the conversion of forests to shrubs and shrubs to cropland from 2001 to 2020. A better understanding of the water cycle response to global change can provide useful knowledge to effectively monitor the water resources security and the allocation of land and water resources in the tropical LMRB. © 2022 Chinese Society of Agricultural Engineering. All rights reserved.
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页码:113 / 122
页数:9
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共 31 条
  • [11] Xu Jing, Hua Jian, Yan Zhongyue, Study on effects of land cover change on runoff simulation result in a headstream watershed, Journal of Nanjing University (Natural Science), 52, 1, pp. 142-148, (2016)
  • [12] Yue Siyu, Li Huaien, Zhao Li, Impacts of climate and land use changes on water scarcity in the Wei River Basin, Research of Soil and Water Conservation, 28, 5, pp. 95-101, (2021)
  • [13] Chen H, Gnanamoorthy P, Chen Y, Et al., Assessment and inter-comparison of multi-source high spatial resolution evapotranspiration products over Lancang-Mekong River Basin, Southeast Asia, Remote Sensing, 14, 3, (2022)
  • [14] Sulla-Menashe D, Gray J M, Abercrombie S P, Et al., Hierarchical mapping of annual global land cover 2001 to present: The MODIS Collection 6 Land Cover product, Remote Sensing of Environment, 222, pp. 183-194, (2019)
  • [15] Mu Q, Heinsch F A, Zhao M, Et al., Development of a global evapotranspiration algorithm based on MODIS and global meteorology data, Remote Sensing of Environment, 111, pp. 519-536, (2007)
  • [16] Mu Q, Zhao M, Running S W., Improvements to a MODIS global terrestrial evapotranspiration algorithm, Remote Sensing of Environment, 115, pp. 1781-1800, (2011)
  • [17] Zhang Y, Kong D, Gan R, Et al., Coupled estimation of 500 m and 8-day resolution global evapotranspiration and gross primary production in 2002-2017, Remote Sensing of Environment, 222, pp. 165-182, (2019)
  • [18] Kim W, Miyata A, Ashraf A, Et al., FluxPro as a realtime monitoring and surveilling system for eddy covariance flux measurement, Journal of Agricultural Meteorology, 71, pp. 32-50, (2015)
  • [19] Kim W, Seo H, Komori D, Et al., Characteristics of the relative sampling error and its application to flux aggregation in eddy covariance measurements, Journal of Agricultural Meteorology, 76, pp. 89-95, (2020)
  • [20] Wohlfahrt G, Haslwanter A, Hortnagl L, Et al., On the consequences of the energy imbalance for calculating surface conductance to water vapour, Agricultural and Forest Meteorology, 149, pp. 1556-1559, (2009)