Degrading river network due to urbanization in Yangtze River Delta

doi:10.1007/s11442-016-1293-0

Abstract

Abstract:

Evolution of river systems under the background of human activities has been a heated topic among geographers and hydrologists. Spatial and temporal variations of river systems during the 1960s-2010s in the Yangtze River Delta (YRD) were investigated based on streams derived from the topographic maps in the 1960s, 1980s and 2010s. A list of indices, drainage density (Dd), water surface ratio (WSR), ratio of area to length of main streams (R), evolution coefficient of tributaries (K) and box dimension (D), were classified into three types (quantitative, structural, and complex indices) and used to quantify the variations of stream structure. Results showed that: (1) quantitative indices (Dd, WSR) presented decreasing trend in the past 50 years, and Dd in Wuchengxiyu, Hangjiahu and Yindongnan have decreased most, about 20%. Structurally, the Qinhuai River basin was characterized by significant upward R, and K value in Hangjiahu went down dramatically by 46.8% during the 1960s-2010s. Decreasing tendency in D was found dominating across the YRD, and decreasing magnitude in Wuchengxiyu and Hangjiahu peaks for 7.8% and 6.5%, respectively in the YRD. (2) Urbanization affected the spatial pattern of river system, and areas with high level of urbanization exhibited least Dd (2.18 km/km²), WSR (6.52%), K (2.64) and D (1.42), compared to moderate and low levels of urbanization. (3) Urbanization also affected the evolution of stream system. In the past 50 years, areas with high level of urbanization showed compelling decreasing tendency in quantitative (27.2% and 19.3%) and complex indices (4.9%) and trend of enlarging of main rivers (4.5% and 7.9% in periods of the 1960s-1980s and the 1980s-2010s). In the recent 30 years, areas with low level of urbanization were detected with significant downward trend in Dd and K. (4) Expanding of urban land, construction of hydraulic engineering and irrigation and water conservancy activities were the main means which degraded the river system in the YRD.

Key words: stream structure, spatial and temporal change, urbanization, Yangtze River Delta

Longfei HAN, Chaogui LEI, Liu YANG, Xiaojun DENG, Chunsheng HU, Guanglai XU. Degrading river network due to urbanization in Yangtze River Delta[J].Journal of Geographical Sciences, 2016, 26(6): 694-706.

Figures/Tables 7

Figure 1

Table 1

Figure 2

Figure 3

Table 2

Table 3

Table 4

References 29

1	Chen Dechao, Li Xiangping, Yang Jishan.et al., 2002. Development of water system in the progress of urbanization of Shanghai and its influences to the city drainage.Urban Problems, (5): 31-35. (in Chinese)
2	Chin A, 2006. Urban transformation of river landscapes in a global context.Geomorphology, 79(3/4): 460-487. doi: 10.1016/j.geomorph.2006.06.033
3	Dunne T, Leopold L B, 1978. Water in Environmental Planning. San Francisco: W.H.Freeman.
4	Elmore A J, Kaushal S S, 2008. Disappearing headwaters: Patterns of stream burial due to urbanization.Frontiers in Ecology and the Environment, 6(6): 308-312. doi: 10.1890/070101
5	Graf W L, 1977. Network characteristics in suburbanizing streams.Water Resources Research, 13(2), 459-463. doi: 10.1029/WR013i002p00459
6	Gregory K J, Davis R J, Downs P W, 1992. Identification of river channel change due to urbanization.Applied Geography, 12(4): 299-318. doi: 10.1016/0143-6228(92)90011-B
7	Hammer T. R, 1972. Stream channel enlargement due to urbanization.Water Resources Research, 8(6), 1530-1540. doi: 10.1029/WR008i006p01530
8	Han Changlai, Mao Rui, 1997. The structure characteristics and the functional variation of the river systems in Taihu Lake catchment.Journal of Lake Science, 9(4): 300-306. (in Chinese) doi: 10.18307/1997.0403
9	Han Longfei, Xu Youpeng, Shao Yulong.et al., 2013. Effect of urbanization on the stream structure and connectivity: A case study in the midlower reaches of the Qinhuai River.Journal of Lake Sciences, 25(3): 335-341. (in Chinese)
10	Han Longfei, Xu Youpeng, Yang Liu.et al., 2015. Temporal and spatial change of stream structure in Yangtze River Delta and its driving forces during 1960s-2010s.Acta Geographica Sinica, 70(5): 819-827. doi: 10.11821/dlxb201505012
11	Horton Robert E, 1945. Erosional development of streams and their drainage basins: Hydrophysical approach to quantitative morphology.Geological Society of America Bulletin, 56(3): 275-370.
12	Huang Yilong, Wang Yanglin, Liu Zhenhuan.et al., 2008. Stream construction characteristics in rapid urbanization area: Shenzhen city as a case.Geographical Research, 27(5): 1212-1220. (in Chinese) doi: 10.1016/S1872-5791(08)60058-5
13	Ji Xiaomin, Xu Youpeng, Han Longfei.et al., 2014. Impacts of urbanization on river system structure: A case study on Qinhuai River Basin, Yangtze River Delta.Water Science & Technology, 70(4): 671-677. doi: 10.2166/wst.2014.278 pmid: 25116497
14	Li Yuanyuan, Li Jianqiang, Li Zongli.et al., 2011. Issues and challenges for the study of the interconnected river system network.Resources Science, 33(3): 386-391. (in Chinese)
15	Marsh George Perkins, 1865. Man and Nature, or Physical Geography as Modified by Human Action. University of Washington Press.
16	Meyer J L, Wallace J B, Press M C et al., 2001. Lost linkages and lotic ecology: Rediscovering small streams. In: Ecology: Achievement and Challenge. The 41st Symposium of the British Ecological Society sponsored by the Ecological Society of America held at Orlando, Florida, USA, 10-13 April 2000. Blackwell Science, 295-317.
17	Ni Jinren, Liu Yuanyuan, 2006. Ecological rehabilitation of damaged river system.Science and Technology Review, 24(7): 17-20. (in Chinese) doi: 10.1016/S1872-2032(06)60052-8
18	Strahler Arthur N, 1957. Quantitative analysis of watershed geomorphology.Eos, Transactions American Geophysical Union, 38(6): 913-920. doi: 10.1029/TR038i006p00913
19	Tian Guangjin, Jiang Jing, Yang Zhifeng.et al., 2011. The urban growth, size distribution and spatio-temporal dynamic pattern of the Yangtze River Delta megalopolitan region, China.Ecological Modelling, 222(3): 865-878. doi: 10.1016/j.ecolmodel.2010.09.036
20	Vanacker Veerle, Molina Armando, Govers Gerard.et al., 2005. River channel response to short-term human-induced change in landscape connectivity in Andean ecosystems.Geomorphology, 72(1): 340-353. doi: 10.1016/j.geomorph.2005.05.013
21	Xiao P F, Wang X H, Feng X Z.et al., 2014. Detecting China’s urban expansion over the past three decades using nighttime light data.IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing, 7(10): 4095-4106.
22	Xu Guanglai, Xu Youpeng, Wang Liuyan, 2013. Temporal and spatial changes of river systems in Hangzhou-Jiaxing-Huzhou Plain during 1960s-2000s.Acta Geographica Sinica, 68(7): 966-974. (in Chinese)
23	Xu Youpeng, 2012. Impacts of Urbanization of the Yangtze River Delta Region on River System in Basins and Hydrological Processes. Beijing: Science Press. (in Chinese)
24	Yang Kai, Yuan Wen, Zhao Jun.et al., 2004. Stream structure characteristics and its urbanization responses to tidal river system.Acta Geographica Sinica, 59(4): 557-564. (in Chinese) doi: 10.3321/j.issn:0375-5444.2004.04.009
25	Yuan Wen, Yang Kai, Tang Min.et al., 2005. Stream structure characteristics and their impact on storage and flood control capacity in the urbanized plain river network.Geographical Research, 24(5): 717-724. (in Chinese) doi: 10.11821/yj2005050008
26	Yuan Wen, Yang Kai, Wu Jianping, 2007. River structure characteristics and classification system in river network plain during the course of urbanization.Scientia Geographica Sinica, 27(3): 401-407. (in Chinese)
27	Zhang Shixia, Guo Yakun, Wang Ziwen, 2015. Correlation between flood frequency and geomorphologic complexity of rivers network: A case study of Hangzhou China.Journal of Hydrology, 527: 113-118. doi: 10.1016/j.jhydrol.2015.04.060
28	Zhou Hongjian, Shi Peijun, Wang Jingai.et al., 2008. River network change and its ecological effects in Shenzhen region in recent 30 years.Acta Geographica Sinica, 63(9): 969-980. (in Chinese) doi: 10.3321/j.issn:0375-5444.2008.09.007
29	Zhou Hongjian, Wang Jingai, Yue Yaojie.et al., 2006. Assessment of flood hazard based on river network change: Taking the Beijing-Tianjin segment of Yongding River watershed as an example.Journal of Natural Disasters, 15(6): 45-49. (in Chinese)

Indices	Definitions	Formulas	Units	Explanations
Dd	Drainage density	Dd=L/A, L is total stream length in the basin, A is area of the basin	km/km²	Dd was firstly introduced by Horton (1945) to indicate the drainage ability
WSR	Water surface ratio	WSR=(A_w/A)×100%, A_w is total water area, including the water area of streams, ponds and lakes	%	WSR denotes the regulating and storing ability
K	Development coefficient of tributaries	K=L_b/L_m, L_b is length of tributaries, L_m is length of main streams	No dimension	K refers to developing degree of tributaries
R	Ratio of area to length of main streams	R=A_m/L_m, A_m is area of the main streams, L_m is length of main streams	km²/km	R is the average width of main streams, indicating developing degree of main stream
D	Box dimension	Intersecting the river networks with square boxes with side length r, count the number N(r) of boxes with stream segments. N(r) increases with decreasing r of the box, and we can get a serial of r-N(r).	No dimension	Fractal theory was first introduced to geography, and it denotes the complexity of the pattern of river network (Zhang et al., 2015).

Indices	Period	Study area					Other areas
Indices	Period	A	B	C	D	E*	Shanghai* (Yang et al., 2004; Yuan et al., 2005)	Pearl River Delta* (Zhou et al., 2008)
Area (km²)	-	3841.0	4914.0	7621.0	497.1	476.1	4962.5	1991.8
Dd	1960s	3.80	3.54	3.75	1.25	3.40	3.45	0.86
	1980s	3.27	3.87	3.24	1.58	3.06		0.84
	2010s	2.93	3.41	2.93	1.14	2.75		0.65
WSR	1960s	6.10	18.86	10.63	5.53	9.50	5.62
	1980s	5.59	17.47	9.88	5.60	7.60
	2010s	4.66	15.20	8.76	7.52	6.70
K	1960s	4.93	2.54	3.65	2.52	3.39	3.39	4.42
	1980s	4.00	3.07	2.83	2.74	2.96		3.04
	2010s	3.83	2.56	1.94	4.37	2.53		3.50
R	1960s	41.53	43.75	45.54	44.11	37.40
	1980s	42.83	48.22	47.03	39.96	34.10
	2010s	38.85	42.94	45.66	73.23	35.60
D	1960s	1.71	1.68	1.69	1.32	1.62	1.40
	1980s	1.65	1.71	1.64	1.32	1.58
	2010s	1.58	1.65	1.58	1.27	1.54

	Administrative division	Urbanization degree (%)*
High level of urbanization	Municipal district of Changzhou	58.15
	Municipal district of Suzhou	57.76
	Municipal district of Wuxi	49.94
	Municipal district of Hangzhou	46.79
Medium level of urbanization	Kunshan County	39.68
	Zhangjiagang County	38.38
	Taicang County	35.62
	Changsu County	34.64
	Wuxian County	31.93
	Wujiang County	30.18
Low level of urbanization	Haining County	29.82
	Haiyan County	22.20
	Qingpu County	22.05

Indices	Periods	Areas of different urbanization degree
Indices	Periods	High level	Medium level	Low level
Dd	1960s	2.45	3.80	4.47
	1980s	2.32	4.04	3.46
	2010s	1.78	3.64	2.96
WSR	1960s	6.88	14.69	17.23
	1980s	7.14	13.51	16.25
	2010s	5.55	11.85	15.30
K	1960s	2.93	4.90	9.12
	1980s	2.90	4.65	6.19
	2010s	2.10	4.57	2.89
R	1960s	40.91	41.39	41.08
	1980s	42.76	45.72	44.39
	2010s	46.14	42.37	40.68
D	1960s	1.45	1.67	1.69
	1980s	1.43	1.69	1.61
	2010s	1.38	1.66	1.61

[1]	FENG Yuxue, LI Guangdong. Interaction between urbanization and eco-environment in the Tibetan Plateau [J]. Journal of Geographical Sciences, 2021, 31(2): 298-324.
[2]	FANG Chuanglin, CUI Xuegang, DENG Xiangzheng, LIANG Longwu. Urbanization and eco-environment coupling circle theory and coupler regulation [J]. Journal of Geographical Sciences, 2020, 30(7): 1043-1059.
[3]	SONG Zhouying, ZHU Qiaoling. Spatio-temporal pattern and driving forces of urbanization in China’s border areas [J]. Journal of Geographical Sciences, 2020, 30(5): 775-793.
[4]	SONG Xiaoqing, WEN Mengmeng, SHEN Yajing, FENG Qi, XIANG Jingwei, ZHANG Weina, ZHAO Guosong, WU Zhifeng. Urban vacant land in growing urbanization: An international review [J]. Journal of Geographical Sciences, 2020, 30(4): 669-687.
[5]	LIU Haimeng, FANG Chuanglin, FANG Kai. Coupled Human and Natural Cube: A novel framework for analyzing the multiple interactions between humans and nature [J]. Journal of Geographical Sciences, 2020, 30(3): 355-377.
[6]	CUI Xuegang, FANG Chuanglin, LIU Haimeng, LIU Xiaofei, LI Yonghong. Dynamic simulation of urbanization and eco-environment coupling: Current knowledge and future prospects [J]. Journal of Geographical Sciences, 2020, 30(2): 333-352.
[7]	ZHANG Xinhuan, XU Wenqiang, XIANG Xinyi, ZHANG Zhiping, CUI Mingjie. Mechanism of interaction between urbanization and resource environment in Central Asia [J]. Journal of Geographical Sciences, 2020, 30(11): 1723-1738.
[8]	MA Haitao, SUN Zhan. Comprehensive urbanization level and its dynamic factors for five Central Asian countries [J]. Journal of Geographical Sciences, 2020, 30(11): 1761-1780.
[9]	HUANG Jinchuan, NA Ying, GUO Yu. Spatiotemporal characteristics and driving mechanism of the coupling coordination degree of urbanization and ecological environment in Kazakhstan [J]. Journal of Geographical Sciences, 2020, 30(11): 1802-1824.
[10]	ZHOU Yannan, YANG Yu, SONG Zhouying, HE Ze, XIA Siyou, REN Yawen. Dynamic transition mechanism analysis of the impact of energy development on urbanization in Central Asia [J]. Journal of Geographical Sciences, 2020, 30(11): 1825-1848.
[11]	JING Cheng, TAO Hui, JIANG Tong, WANG Yanjun, ZHAI Jianqing, CAO Lige, SU Buda. Population, urbanization and economic scenarios over the Belt and Road region under the Shared Socioeconomic Pathways [J]. Journal of Geographical Sciences, 2020, 30(1): 68-84.
[12]	LYU Lachang, SUN Feixiang, HUANG Ru. Innovation-based urbanization: Evidence from 270 cities at the prefecture level or above in China [J]. Journal of Geographical Sciences, 2019, 29(8): 1283-1299.
[13]	Liying GUO, Liping DI, Qing TIAN. Detecting spatio-temporal changes of arable land and construction land in the Beijing-Tianjin corridor during 2000-2015 [J]. Journal of Geographical Sciences, 2019, 29(5): 702-718.
[14]	ZHUANG Liang, YE Chao, HU Senlin. Spatial production and spatial dialectic: Evidence from the New Urban Districts in China [J]. Journal of Geographical Sciences, 2019, 29(12): 1981-1998.
[15]	CHEN Mingxing, YE Chao, LU Dadao, SUI Yuwen, GUO Shasha. Cognition and construction of the theoretical connotations of new urbanization with Chinese characteristics [J]. Journal of Geographical Sciences, 2019, 29(10): 1681-1698.