Journal of Tropical Oceanography >
Evolution of water level profile dynamics in the Modaomen estuary of the Pearl River and its responses to human activities*
Received date: 2021-06-09
Revised date: 2021-08-05
Online published: 2021-08-16
Supported by
National Key Research and Development Program of China(2016YFC0402600)
National Natural Science Foundation of China(41106015)
National Natural Science Foundation of China(42076171)
National Natural Science Foundation of China(51979296)
Science and Technology Planning Project of Guangdong Province, China(202002030452)
Water Resource Science and Technology Innovation Program of Guangdong Province(2016-20)
The water level in the estuary area is affected by many factors, such as runoff, tide and topography, resulting in a complex pattern in spatial morphology. Understanding the evolution characteristics of water level distribution is essential for sustainable water resources managements in estuaries. In this study, we use the residual water level data from six gauge stations (Makou, Ganzhu, Jiangmen, Zhuyin, Denglongshan, and Sanzao stations) along the Modaomen estuary of the Pearl River during 1965 to 2016, together with the monthly averaged river discharge data from the Makou hydrological station during the corresponding period. With a bivariate variable linear regression model, we quantitatively identify the influence of human activities on water surface profile dynamics, and attempt to understand the coupling relationship among human activity, dynamic structure and morphological change. The results show that the bulk parameters displaying the shape of water level profile (i.e., curvature) can well indicate the trends of erosion and deposition of river bed, with the positive curvature indicating sedimentation tendency and the negative curvature indicating erosion tendency. In the central part of the Modaomen estuary, such as the Jiangmen-Ganzhu reach, there exists an area where the water level slope is considerably reduced, especially during the dry season when the water level slope even fluctuates negatively in the landward direction. The river-bed deepening caused by human activities such as land reclamation, sand excavation and river dredging are the main reason for the alteration in spatial dynamics of the water surface profiles in the Modaomen estuary. We show that the river-bed deepening causes the water level curvature of the seaward reach (Sanzao to Zhuyin reach) and the upper reach (Ganzhu to Makou reach) decreasing by 0.41×10-4 m·km-2 and 1.04×10-4 m·km-2, respectively, while the central reach of the estuary (Zhuyin to Ganzhu reach) increasing by 0.21×10-4 m·km-2; the water surface shape changes from concave (C>0) - convex (C<0) - concave to convex - concave - convex, and the trends of erosion and deposition of river bed are also adjusted accordingly.
MA Yuting , CAI Huayang , YANG Hao , LIU Feng , CHEN Ou , XIE Rongyao , OU Suying , YANG Qingshu . Evolution of water level profile dynamics in the Modaomen estuary of the Pearl River and its responses to human activities*[J]. Journal of Tropical Oceanography, 2022 , 41(2) : 52 -64 . DOI: 10.11978/2021072
表1 磨刀门河口双变量三参数线性回归模型的率定结果Tab. 1 Calibration of the bivariate linear regression model with three parameters in the Modaomen estuary |
站点 | 缓变阶段 | 调整阶段 | |||||
---|---|---|---|---|---|---|---|
α1 | α2 | β | RMSE | R2 | RMSE | R2 | |
马口 | 2.78×10-4 | 0.33 | -0.29 | 0.38 | 0.94 | 0.22 | 0.93 |
甘竹 | 1.57×10-4 | 0.61 | -0.10 | 0.26 | 0.91 | 0.08 | 0.97 |
江门 | 1.14×10-4 | 0.67 | 0.09 | 0.21 | 0.89 | 0.09 | 0.95 |
竹银 | 0.46×10-4 | 0.83 | 0.03 | 0.07 | 0.94 | 0.05 | 0.93 |
灯笼山 | 0.19×10-4 | 0.86 | 0.03 | 0.04 | 0.92 | 0.03 | 0.94 |
图5 磨刀门河口缓变阶段回归模型的率定(a、c、e、g、i)和调整阶段水位变化过程的反演(b、d、f、h、j)a、b为马口站; c、d为甘竹站; e、f为江门站; g、h为竹银站; i、j为灯笼山站。图中虚线为1:1率定中线 Fig. 5 Calibration of the regression model in the pre-human period (a, c, e, g, i) and reconstruction of the water level in the post-human period (b, d, f, h, j) in the Modaomen estuary |
图6 磨刀门河口水位Z(a)、水位坡降S (b)、水位曲率C (c)变化值的沿程变化 Fig. 6 Longitudinal variations in the residual water level (a), residual water level slope (b) and the residual water level curvature (c) along the Modaomen estuary |
表2 强人类活动对沿程水位、坡降、曲率的影响程度Tab. 2 Influence of strong human interventions on the residual water level, slope and curvature along the estuary |
三灶—灯笼山 | 灯笼山—竹银 | 竹银—江门 | 江门—甘竹 | 甘竹—马口 | ||
---|---|---|---|---|---|---|
余水位/m | △TOT | -0.029 | -0.070 | -0.292 | -0.461 | -0.634 |
△GEO | -0.015 | -0.036 | -0.219 | -0.341 | -0.450 | |
△BOU | -0.015 | -0.034 | -0.073 | -0.119 | -0.185 | |
余水位坡降/(×10-2m·km-1) | △TOT | -0.198 | -0.245 | -1.039 | 0.001 | -0.876 |
△GEO | -0.131 | -0.125 | -0.880 | 0.169 | -0.669 | |
△BOU | -0.068 | -0.120 | -0.160 | -0.167 | -0.207 | |
余水位曲率/(×10-4m·km-2) | △TOT | -0.137 | -0.882 | 0.230 | 0.187 | -1.122 |
△GEO | -0.064 | -0.755 | 0.286 | 0.157 | -1.044 | |
△BOU | -0.098 | -0.121 | -0.062 | -0.007 | -0.058 |
注: △TOT表示总变化量, △GEO表示地形边界影响量, △BOU表示动力边界影响量 |
表3 磨刀门河口不同河段曲率与冲淤趋势的对应关系Tab. 3 Correlation between curvature and tendency of erosion and deposition in different reaches of the Modaomen estuary |
年份 | 河段 | 平均水深变化/m | 实测冲淤变化 | 曲率/(×10-4m·km-2) | 动力反演冲淤趋势 |
---|---|---|---|---|---|
1962—1977 | 三灶至灯笼山 | / | / | 0.66 | 淤积 |
灯笼山至竹银 | -0.10 | 淤积 | 1.23 | 淤积 | |
竹银至百顷头 | -0.25 | 淤积 | 0.26 | 淤积 | |
百顷头至甘竹 | 0.11 | 侵蚀下切 | -1.24 | 冲刷 | |
甘竹至马口 | 0.22 | 侵蚀下切 | 1.30 | 淤积 | |
1977—1999 | 三灶至灯笼山 | / | / | -0.01 | 冲刷 |
灯笼山至竹银 | 0.21 | 侵蚀下切 | 0.75 | 淤积 | |
竹银至百顷头 | 0.40 | 侵蚀下切 | 0.15 | 淤积 | |
百顷头至甘竹 | 0.23 | 侵蚀下切 | -1.47 | 冲刷 | |
甘竹至马口 | -0.04 | 微淤 | 1.71 | 淤积 | |
1999—2005 | 三灶至灯笼山 | / | / | -0.28 | 冲刷 |
灯笼山至竹银 | -0.06 | 微淤 | 0.04 | 淤积 | |
竹银至百顷头 | 0.25 | 侵蚀下切 | -0.01 | 冲刷 | |
百顷头至甘竹 | 0.46 | 侵蚀下切 | -0.26 | 冲刷 | |
甘竹至马口 | 1.06 | 侵蚀下切 | 0.89 | 淤积 | |
2005—2013 | 三灶至灯笼山 | / | / | 0.53 | 淤积 |
灯笼山至竹银 | 0.72 | 侵蚀下切 | -0.26 | 冲刷 | |
竹银至百顷头 | 0.80 | 侵蚀下切 | -0.20 | 冲刷 | |
百顷头至甘竹 | -0.02 | 微淤 | 0.11 | 淤积 | |
甘竹至马口 | 0.31 | 侵蚀下切 | -0.01 | 冲刷 |
注: 地形资料仅有1962、1977、1999、2005、2013年份数据, 三灶至灯笼山段无地形统计数据, 表中用斜杠表示; 前人研究未在江门进行分段统计, 故表中将江门替换成百顷头; 1962年至1964年无曲率数据, 故第一阶段曲率采用1965年至1977年的平均值; 表中加粗部分表示实测冲淤变化与曲率反演结果不匹配的情况 |
*感谢所有对本文付出努力的人, 感谢河口海岸研究所团队, 感谢各位审稿专家对本文提出的宝贵建议。
[1] |
陈吉余, 程和琴, 戴志军, 2008. 河口过程中第三驱动力的作用和响应--以长江河口为例[J]. 自然科学进展, 18(9): 994-1000. (in Chinese)
|
[2] |
韩志远, 田向平, 欧素英, 2010. 人类活动对磨刀门水道河床地形和潮汐动力的影响[J]. 地理科学, 30(4): 582-587.
|
[3] |
洪鹏锋, 杜文印, 2019. 强人类活动驱动下珠江磨刀门河口潮汐动力增强原因初探[J]. 人民珠江, 40(9): 28-32.
|
[4] |
胡煌昊, 徐阳, 官明开, 等, 2016. 珠江河口水下三角洲冲淤演变分析[J]. 水道港口, 37(6): 593-598.
|
[5] |
黎开志, 周文浩, 钱挹清, 等, 2005. 珠江磨刀门整治效果分析[J]. 人民珠江, (S1): 31-34. (in Chinese)
|
[6] |
刘锋, 田向平, 韩志远, 等, 2011. 近四十年西江磨刀门水道河床演变分析[J]. 泥沙研究, (1): 45-50.
|
[7] |
吕海滨, 吴超羽, 刘斌, 2006. 珠江口磨刀门整治前后水动力数值模拟[J]. 海洋科学, 30(11): 58-63.
|
[8] |
倪晋仁, 1990. 关于悬移质输沙率计算模式的探讨[J]. 水利学报, (8): 10-19.
|
[9] |
钱挹清, 2004. 珠江三角洲河道无序采沙影响及管理措施[J]. 人民珠江, (2): 44-46, 58.
|
[10] |
杨昊, 欧素英, 傅林曦, 等, 2020. 珠江磨刀门河口日均水位变化及影响因子辨识[J]. 水利学报, 51(7): 869-881.
|
[11] |
袁建国, 廖志伟, 2009. 珠江河口综合治理概述[J]. 人民珠江, 30(S2): 13-14, 18.
|
[12] |
张红武, 张俊华, 卜海磊, 等, 2011. 试论推移质输沙率公式[J]. 南水北调与水利科技, 9(6): 140-145.
|
[13] |
张先毅, 黄竞争, 杨昊, 等, 2019. 长江河口潮波传播机制及阈值效应分析[J]. 海洋与湖沼, 50(4): 788-798.
|
[14] |
张先毅, 杨昊, 黄竞争, 等, 2020. 强人类活动驱动下珠江磨刀门河口径潮动力的季节性异变特征[J]. 海洋与湖沼, 51(5): 1043-1054.
|
[15] |
张子昊, 2018. 人类活动影响下珠江网河河道演变与机制[D]. 广州: 中山大学: 55-61.
|
[16] |
郑国栋, 2005. 人类活动对珠江三角洲水动力环境影响研究[D]. 武汉: 武汉大学: 87-97.
|
[17] |
邹志利, 2009. 海岸动力学[M]//邹志利. 沙质海岸泥沙运动. 4版. 北京: 人民交通出版社: 159-176. (in Chinese)
|
[18] |
|
[19] |
|
[20] |
|
[21] |
|
[22] |
|
[23] |
|
[24] |
|
[25] |
|
[26] |
|
/
〈 | 〉 |