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Remote Sensing for Land & Resources    2019, Vol. 31 Issue (4) : 104-111     DOI: 10.6046/gtzyyg.2019.04.14
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GIS-based estimation of fractal dimension and geomorphological development of the water system in the dam construction area
Quan AN1,3, Zhonghua HE1,2,3(), Cuiwei ZHAO1, Hong LIANG1,3, Shulin JIAO1,3, Chaohui YANG4
1. School of Geographic and Environmental Science, Guizhou Normal University, Guiyang 550001, China
2. State Engineering Technology Institute For Karst Desertification Control, Guizhou Normal University, Guiyang 550001,China
3. Key Laboratory of Remote Sensing Application on Mountain Resources and Environment in Guizhou Province, Guiyang 550001, China
4. Department of Emergency Management of Guizhou Province, Guiyang 550001, China
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Abstract  

The fractal dimension of water system is one of the quantitative representation methods for determining geomorphic development degree. The study of water system fractal dimension is of great significance for the investigation of the sedimentation mechanism of karst dam basin landform. Advanced space borne thermal emission and reflection radio mater global digital elevation model (ASTER-GDEM) was used as a data source for extracting water system and 30 m resolution ASTER-GDEM. Based on the ArcGIS 10.2, Horton-Strahler theory, water grid method and fishing net method, the authors estimated the water system fractal dimension of Longchangqiao watershed in the dam construction area of Yuzhong, and explore the influence of landform development on the hydrological characteristics of the basin in dam construction. Some conclusions have been reached: The fractal dimensions of the water system estimated by different methods and different data sources under the complex geomorphic structure of the karst area are quite different. The fractal dimension values of the extracted water system of 1.50 million topographic maps estimated by the Horton-Strahler method, the water grid method and the fishing net method are 1.69, 1, 53, 1.54 respectively. The fractal dimensions estimated by 30 m resolution ASTER-GDEM extraction water system are 0.66, 1.59, 1.60. Among them, the fractal dimension values estimated by the Horton-Strahler method are significantly different, with the difference reaching 1.03. Comprehensive analysis of Horton-Strahler theory, water grid method and fishing net method for estimating the relationship between the fractal dimension of different data source water systems and actual landform development in karst dam construction area shows that the water system fractal dimension estimated by the fishing net method and the actual landform status of the study area are most consistent with each other. According to the estimation of the water system estimated by the fishing net, the fractal dimension of the extracted water system estimated by the fishing net method is 1.54, and the fractal dimension estimated by the 30 m resolution ASTER-GDEM extraction system is about 1.60, which suggests that the study area is at the late stage of the young period and the early stage of mature period in geomorphological development, and the results coincide with the actual development of the study area. In addition, three methods were used to estimate the fractal dimension accuracy of the water system in the karst dam basin, and the results show the following order: fishnet method>water grid method>Horton-Strahler method.
Keywords GIS      karst landform      ASTER-GDEM      fractal dimension      adaptive analysis     
:  P33  
Corresponding Authors: Zhonghua HE     E-mail: zhonghuahe@gznu.edu.cn
Issue Date: 03 December 2019
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Quan AN
Zhonghua HE
Cuiwei ZHAO
Hong LIANG
Shulin JIAO
Chaohui YANG
Cite this article:   
Quan AN,Zhonghua HE,Cuiwei ZHAO, et al. GIS-based estimation of fractal dimension and geomorphological development of the water system in the dam construction area[J]. Remote Sensing for Land & Resources, 2019, 31(4): 104-111.
URL:  
https://www.gtzyyg.com/EN/10.6046/gtzyyg.2019.04.14     OR     https://www.gtzyyg.com/EN/Y2019/V31/I4/104
Fig.1  Research area overview
河流
等级		 数目/条 平均长
度/km		 分叉比/
Rx		 河长比/
RL		 lgRx lgRL
1 1 557 1 191.470
1.981 0.559 0.297 -0.252
2 786 666.210
2.005 0.560 0.302 -0.520
3 392 373.230
3.187 0.458 0.503 -0.298
4 123 171.010
2.617 0.481 0.418 -0.379
5 47 82.330
5.875 0.395 0.769 -0.114
6 8 32.520
Tab.1  Horton-Strahler method parameters based on water system of topographic map
河流
等级		 数目/条 平均长
度/km		 Rb RL lgRb lgRL
1 877 1 363.910
2.016 0.486 0.305 -0.516
2 435 663.030
2.112 0.464 0.325 -0.489
3 206 307.920
1.392 0.622 0.144 -0.843
4 148 191.470
2.056 0.526 0.313 -0.505
5 72 100.750
72.000 0.028 1.857 0.269
6 1 2.850
Tab.2  Horton-Strahler method parameters based on water system of ASTER-GDEM
1:5万栅格水系法 30 m空间分辨率ASTER-GDEM栅格水系法
栅格边长r 栅格数目N(r) Lgr LgN(r) 栅格边长r 栅格数目N(r) Lgr LgN(r)
500 4 975 2.699 3.697 500 5 754 2.699 3.760
1 000 2 161 3.000 3.335 1 000 2 614 3.000 3.417
1 500 1 225 3.176 3.088 1 500 1 526 3.176 3.184
2 000 810 3.301 2.908 2 000 1 004 3.301 3.002
2 500 569 3.398 2.755 2 500 675 3.398 2.829
3 000 424 3.477 2.627 3 000 491 3.477 2.691
3 500 328 3.544 2.516 3 500 374 3.544 2.573
4 000 269 3.602 2.430 4 000 295 3.602 2.470
4 500 216 3.653 2.334 4 500 244 3.653 2.387
5 000 187 3.699 2.272 5 000 205 3.699 2.312
5 500 161 3.740 2.207 5 500 163 3.740 2.212
6 000 143 3.778 2.155 6 000 146 3.778 2.164
6 500 117 3.813 2.068 6 500 131 3.813 2.117
7 000 106 3.845 2.025 7 000 114 3.845 2.057
7 500 93 3.875 1.968 7 500 100 3.875 2.000
8 000 85 3.903 1.929 8 000 90 3.903 1.954
8 500 78 3.929 1.892 8 500 79 3.929 1.898
9 000 70 3.954 1.845 9 000 76 3.954 1.881
9 500 65 3.978 1.813 9 500 69 3.978 1.839
10 000 59 4.000 1.771 10 000 64 4.000 1.806
Tab.3  Water system of topographic map and ASTER-GDEM grid parameters
地形图水系渔网法 ASTER-GDEM水系渔网法
栅格边长r 栅格数目N(r) Lgr LgN(r) 栅格边长r 栅格数目N(r) Lgr LgN(r)
500 5 023 2.699 3.701 500 5 723 2.699 3.758
1 000 2 169 3.000 3.336 1 000 2 574 3.000 3.411
1 500 1 238 3.176 3.093 1 500 1 561 3.176 3.193
2 000 800 3.301 2.903 2 000 996 3.301 2.998
2 500 566 3.398 2.753 2 500 686 3.398 2.836
3 000 427 3.477 2.630 3 000 491 3.477 2.691
3 500 322 3.544 2.508 3 500 373 3.544 2.572
4 000 264 3.602 2.422 4 000 295 3.602 2.470
4 500 221 3.653 2.344 4 500 238 3.653 2.377
5 000 177 3.699 2.248 5 000 200 3.699 2.301
5 500 154 3.740 2.188 5 500 172 3.740 2.236
6 000 131 3.778 2.117 6 000 143 3.778 2.155
6 500 121 3.813 2.083 6 500 126 3.813 2.100
7 000 101 3.845 2.004 7 000 113 3.845 2.053
7 500 92 3.875 1.964 7 500 101 3.875 2.004
8 000 80 3.903 1.903 8 000 90 3.903 1.954
8 500 74 3.929 1.869 8 500 82 3.929 1.914
9 000 68 3.954 1.833 9 000 71 3.954 1.851
9 500 64 3.978 1.806 9 500 65 3.978 1.813
10 000 57 4.000 1.756 10 000 61 4.000 1.785
Tab.4  Water system of topographic map and ASTER-GDEM fishing net method parameters
参数 地形图水系 ASTER-GDEM水系
Horton-
Strahler法		 栅格水
系法		 渔网
法		 Horton-
Strahler法		 栅格水
系法		 渔网
法
分维值 1.69 1.53 1.54 0.66 1.59 1.60
R2 0.996 6 0.996 4 0.994 1 0.993 4
Tab.5  Comparison of fractal values from water system of topographic map and ASTER-GDEM by different methods
Fig.2  Landform types and mountain shadow maps of various watersheds in the study area
流域 地貌
类型		 面积/
km2		 占向阳流
域比例		 占研究
区比例		 成因类型①
向阳流域 K化低山谷地 29.46 3.54 0.72 F
K化中山谷地 59.01 7.09 1.45 K2
峰丛谷地 193.88 23.31 4.76 K1,K2
峰丛洼地 60.94 7.33 1.5 K2
峰林溶原(盆地) 173.25 20.83 4.25 K1、K2
浅切中山 316.39 38.04 7.77 F
阳长流域 K化中山谷地 427.07 26.75 10.48 F,K1,K2
峰丛谷地 757.33 47.43 18.59 K1,K2
峰丛洼地 185.6 11.62 4.56 K1,K2
峰林溶原(盆地) 128.82 8.07 3.16 K1,K2
浅切中山 102.38 6.41 2.51 F
深切中山 36.65 3.01 0.9 F
龙场桥流域 K化低山谷地 16.88 1.03 0.41 K2
K化中山谷地 711.24 43.23 17.46 K1,K2
峰丛谷地 196.62 11.95 4.83 K1,K2
峰丛洼地 676.79 41.14 16.61 K1,K2
深切中山 43.53 2.64 1.07 F
Tab.6  Geomorphological development parameters and area ratio of different watersheds
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