Hydrological Change and Its Causes in the River Network of the Pearl River Delta
Received date: 2002-01-10
Revised date: 2002-03-18
Online published: 2002-07-25
Supported by
National Natural Science Foundation of China, No. 49971019
This paper aims to summarize and illustrate a variety of human-induced hydrologic and geomorphic changes in the Pearl River Delta (PRD) and to analyse the causes and effects.The hydrologic characteristics of the river network have been altered in the following three main aspects. First, stage has become higher or lower over the past decades in an uneven manner in the delta. From the early 1950s to the 1980s, scattered and small embankments were enlarged and combined to expand land mass and reduce flood hazards in the PRD. However, reduction of water surface area and concentration of flow into major channels generally caused stage to go up slightly. Secondly, corresponding to the stage changes, the stage-discharge relationship has been substantially modified, as evidenced by over 2 m drop of stage for the same amount of discharge. Thirdly, the ratio of flow partition into two channels at several river bifurcation points has continuously changed over the past decade. Closely associated with the hydrologic changes are alterations of river channel and estuarine morphologies. Such geomorphic changes primarily include noticeable or even alarmingly severe modification of river channel bed, extension of river mouth and contraction of estuary in the study region. It was found that the hydrologic and geomorphic changes that have occurred within a relatively short period of time are mainly consequences of a wide variety of human activities, coupled with influences of natural events, including (a) channel dredging of sand for construction usage, (b) combination of embankments and construction of dams, (c) channel constriction and reduction or complete loss of floodplain, (d) sea level rise, and (e) channel bed erosion by record floods.
CHEN Xiaohong, CHEN Yongqin . Hydrological Change and Its Causes in the River Network of the Pearl River Delta[J]. Acta Geographica Sinica, 2002 , 57(4) : 429 -436 . DOI: 10.11821/xb200204007
[1] Xu Hailiang. The preliminary study on environmental change of estuary and its hydrological modeling: a case study of Zhujiang Estuary. Tropical Geography, 1998, 18(2): 162-167.
[徐海亮. 河口环境变异与水文模拟计算初探—以珠江河口网河区为例. 热带地理, 1998, 18(2): 162-167.]
[2] Chen Xiaohong. Recognition of temporal change of hydrological feature. Acta Scientiarum Naturalium Universitatis Sunyatseni, 2000, 39(1).
[陈晓宏. 洪水特征的时间变异性识别. 中山大学学报 (自然科学版), 2000, 39(1): 96-100.]
[3] He Yizhao, Han Tianhuai. Revision of the forecasting program for peak stage at Gaoyao of Xijiang River. Pearl River, 1998, (5): 8-10.
[何以昭, 韩天槐. 西江干流高要洪峰水位预报方案修正的探讨. 人民珠江, 1998, (5): 8-10.]
[4] Li Tianjian. Analysis on hydrological factors and geomorphologic change of rivers. Guangdong Water Resources and Hydro-electrics, 2001, (suppl.): 32-33.
[李天坚. 水文要素与河道变化的分析. 广东水利水电, 2001, (增刊): 32-33.]
[5] Szilagyi J. Identifying cause of declining flows in the Republican River. J. Water Resources Planning and Management, ASCE, 2001, 127(4): 244-253.
[6] Committee on American River Flood Frequencies. Improving American River Flood Frequency Analysis. Washington: National Academy Press, D. C., 1999.
[7] Pinter N, Tomas R, Wlosinski J H. Assessing flood hazard on dynamic rivers. EOS, 2001, 82(31): 333-339.
[8] Dai Liangsheng. Review of the reclamation project at Baiteng Lake. Pearl River, 1981, (2): 1-11.
[戴良生. 白藤堵海工程的回顾. 人民珠江, 1981, (2): 1-11.]
[9] Zeng Zhaoxuan, Qiu Shijun. The influence of sea level rise on the Pearl River Delta. Pearl River, 1994, (1): 6-9.
[曾昭璇, 丘世钧. 珠江口海平面上升对三角洲的影响. 人民珠江, 1994, (1): 6-9.]
[10] Huang Zhenguo, Zhang Weiqiang, Lai Guanwen et al. The influence of sea level rising on the embankments in the Zhujiang Delta. Acta Geographica Sinica, 1999, 54(6): 518-525.
[黄镇国, 张伟强, 赖冠文 等. 珠江三角洲海平面上升对堤围防御能力的影响. 地理学报, 1999, 54(6): 518-525.]
/
| 〈 |
|
〉 |