›› 2013, Vol. 23 ›› Issue (4): 612-626.doi: 10.1007/s11442-013-1032-8

• Research Articles • 上一篇    下一篇

Hydroclimatological changes in the Bagmati River Basin, Nepal

  

  1. 1. Department of Environmental Science and Engineering, School of Science, Kathmandu University, Nepal;
    2. Institute of Geographic Sciences and Natural Resources Research, CAS, Beijing 100101, China;
    3. Institute of Remote Sensing Applications, CAS, Beijing 100101, China
  • 收稿日期:2012-07-12 修回日期:2013-04-05 出版日期:2013-08-15 发布日期:2013-08-15
  • 作者简介:Yam Prasad Dhital, Ph.D Candidate, specialized in flood hydrology and hydroclimatological changes. E-mail: yam@ku.edu.np
  • 基金资助:

    This work was supported by the Chinese Academy of Sciences (CAS), China, and TWAS, the Academy of Sciences for the Developing World, 3240240226

Hydroclimatological changes in the Bagmati River Basin, Nepal

Yam Prasad DHITAL, TANG Qiuhong, SHI Jiancheng   

  1. 1. Department of Environmental Science and Engineering, School of Science, Kathmandu University, Nepal;
    2. Institute of Geographic Sciences and Natural Resources Research, CAS, Beijing 100101, China;
    3. Institute of Remote Sensing Applications, CAS, Beijing 100101, China
  • Received:2012-07-12 Revised:2013-04-05 Online:2013-08-15 Published:2013-08-15
  • About author:Yam Prasad Dhital, Ph.D Candidate, specialized in flood hydrology and hydroclimatological changes. E-mail: yam@ku.edu.np
  • Supported by:

    This work was supported by the Chinese Academy of Sciences (CAS), China, and TWAS, the Academy of Sciences for the Developing World, 3240240226

摘要:

Study on hydroclimatological changes in the mountainous river basins has attracted great interest in recent years. Changes in temperature, precipitation and river discharge pattern could be considered as indicators of hydroclimatological changes of the river basins. In this study, the temperatures (maximum and minimum), precipitation, and discharge data from 1980 to 2009 were used to detect the hydroclimatological changes in the Bagmati River Basin, Nepal. Simple linear regression and Mann-Kendall test statistic were used to examine the significant trend of temperature, precipitation, and discharge. Increasing trend of temperature was found in all seasons, although the change rate was different in different seasons for both minimum and maximum temperatures. However, stronger warming trend was found in maximum temperature in comparison to the minimum in the whole basin. Both precipitation and discharge trend were increasing in the pre-monsoon season, but decreasing in the post-monsoon season. The significant trend of precipitation could not be observed in winter, although discharge trend was decreasing. Furthermore, the intensity of peak discharge was increasing, though there was not an obvious change in the intensity of maximum precipitation events. It is expected that all these changes have effects on agriculture, hydropower plant, and natural biodiversity in the mountainous river basin of Nepal.

关键词: Bagmati River Basin, hydroclimatological change, temperature, precipitation, discharge

Abstract:

Study on hydroclimatological changes in the mountainous river basins has attracted great interest in recent years. Changes in temperature, precipitation and river discharge pattern could be considered as indicators of hydroclimatological changes of the river basins. In this study, the temperatures (maximum and minimum), precipitation, and discharge data from 1980 to 2009 were used to detect the hydroclimatological changes in the Bagmati River Basin, Nepal. Simple linear regression and Mann-Kendall test statistic were used to examine the significant trend of temperature, precipitation, and discharge. Increasing trend of temperature was found in all seasons, although the change rate was different in different seasons for both minimum and maximum temperatures. However, stronger warming trend was found in maximum temperature in comparison to the minimum in the whole basin. Both precipitation and discharge trend were increasing in the pre-monsoon season, but decreasing in the post-monsoon season. The significant trend of precipitation could not be observed in winter, although discharge trend was decreasing. Furthermore, the intensity of peak discharge was increasing, though there was not an obvious change in the intensity of maximum precipitation events. It is expected that all these changes have effects on agriculture, hydropower plant, and natural biodiversity in the mountainous river basin of Nepal.

Key words: Bagmati River Basin, hydroclimatological change, temperature, precipitation, discharge