Journal of Geo-information Science >
Geological Hazard Risk Assessment Based on Information Quantity Model in Fuling District, Chongqing City, China
Received date: 2015-03-24
Request revised date: 2015-06-10
Online published: 2015-12-20
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Using geospatial technologies to assess geological hazard risk has been proved feasible, effective and important in the southwest of China, which is featured by mountainous landscape and the population density is very large. The main objective of this study is to make the risk assessment of the geological hazards in Fuling district using information quantity model, and eight triggering factors are used, including slope, aspect, cumulative catchment area, formation lithology, distances to water, precipitation, vegetation, and land use/land cover type respectively. GaoFen-1 image of December 24, 2013 is used to extract two dynamic triggering factors, vegetation and land use, and precipitation is also taken as a dynamic triggering factor. All triggering factors were then used to construct an information model to assess and predict the geological hazards in the study area in December 2013, producing a geological hazard risk distribution map. Finally, ROC curve was used to validate the information model. The statistical results indicate that the areas with high risk zone is about 9.73% of the entire area and that the percentage of the geological hazards sites is about 52.7% of the entire geological hazards sites. And it shows a satisfactory consistency between the susceptibility map and the geological hazard locations. The AUC of success-rate ROC of 0.796 and the AUC of prediction-rate ROC of 0.748 demonstrate the robustness and relatively good reliability of the information quantity model. Above all, the model can be applied to interpret and predict the geological hazard occurrences in the study area.
TAN Yumin , GUO Dong , BAI Bingxin , XU Bo . Geological Hazard Risk Assessment Based on Information Quantity Model in Fuling District, Chongqing City, China[J]. Journal of Geo-information Science, 2015 , 17(12) : 1554 -1562 . DOI: 10.3724/SP.J.1047.2015.01554
Fig. 1 Methodology flow chart图1 地质灾害易发性评价流程 |
Fig. 2 Study area图2 研究区位置 |
Fig. 3 Slope distribution图3 坡度分布图 |
Fig. 4. Slope aspect distribution图4 坡向分布图 |
Fig. 5 Cumulative catchment area图5 累计汇水面积分布图 |
Fig. 6 Formation lithology图6 地层岩性(地质因子)分布图 |
Fig. 7 Multiple buffer zones of surface stream and river network图7 水域缓冲(地表水因子)分布图 |
Fig. 8 Land use/Land cover map图8 土地利用分类图 |
Fig. 9 Vegetation NDVI distribution map图9 植被(NDVI)分布 |
Tab. 1 Example of precipitation in Fuling district表1 涪陵区部分降雨量信息 |
站点 | 日降雨 | rain5d | rain4d | rain3d | rain2d | rain1d |
---|---|---|---|---|---|---|
白涛 | 0 | 0 | 0.5 | 0 | 0 | 0 |
百胜 | 0 | 0 | 0.8 | 0 | 0.1 | 0.1 |
从林 | 0 | 0 | 1.7 | 0 | 0.1 | 0.5 |
大木 | 0.1 | 0 | 2.5 | 0.1 | 0 | 0.1 |
大溪 | 0 | 0 | 1.7 | 0 | 0 | 0.2 |
对比站 | 0 | 0 | 0 | 0 | 0 | 0 |
涪陵本站 | 0 | 0 | 1.7 | 0 | 0.5 | 0.4 |
明家 | 0.1 | 0 | 0.8 | 0.1 | 0.5 | 0.1 |
注:rain1d,…,rain5d分别表示相对0天前第1-5天日降雨量 |
Tab. 2 Example information values for individual triggering factors表2 影响因子信息量计算表 |
地质灾害因子 | 分段 | 地灾个数(个) | 信息量 | 信息量主要排序 |
---|---|---|---|---|
坡度(°) | 0~5 | 18 | -1.514609 | - |
5~10 | 31 | -0.352688 | - | |
10~15 | 87 | 0.530870 | 11 | |
15~20 | 56 | 0.667521 | 8 | |
20~25 | 4 | -1.244959 | - | |
坡向(°) | 平坦 | 5 | -2.08588 | - |
0~30 | 10 | -0.326033 | - | |
30~150 | 66 | 0.189856 | 19 | |
150~200 | 21 | -0.005354 | - | |
200~250 | 30 | 0.372565 | 16 | |
250~310 | 32 | -0.020237 | - | |
310~330 | 13 | 0.04228 | - | |
330~360 | 19 | 0.357179 | 17 | |
累积汇水面积 (格网) | 1~2 | 114 | 0.100335 | 21 |
2~4 | 31 | 0.437477 | 15 | |
4~8 | 15 | -0.550313 | - | |
8~20 | 21 | 0.162117 | 20 | |
>20 | 15 | -0.793704 | - | |
土地利用类型 | 耕地 | 76 | 0.503849 | 12 |
林地 | 61 | -7.919041 | - | |
园地 | 19 | 1.316537 | 2 | |
草地 | 5 | -0.589446 | - | |
交通运输用地 | 2 | 0.743452 | 7 | |
水域及水利设施用地 | 11 | 0.478293 | 13 | |
城镇村及工矿用地 | 22 | 2.009376 | 1 | |
离地表水距离 (m) | 0~150 | 97 | 1.218703 | 3 |
150~250 | 60 | 1.187452 | 4 | |
250~400 | 21 | -0.728606 | - | |
>400 | 18 | -2.39345 | - | |
地层岩性 | 三叠系中统雷口坡组 | 0 | 0 | - |
三叠系下统嘉陵江组 | 12 | -1.138709 | - | |
三叠系上统须家河组 | 0 | 0 | - | |
侏罗系下统珍珠冲组 | 0 | 0 | - | |
侏罗系中统新田沟组 | 0 | 0 | - | |
二迭系上统 | 0 | 0 | - | |
侏罗系上统蓬莱镇组 | 2 | -3.63999 | - | |
侏罗系中统上沙溪庙组 | 106 | 0.783518 | 6 | |
二迭系下统 | 0 | 0 | - | |
三叠系下统飞仙关组 | 0 | 0 | - | |
志留系下统罗惹坪组 | 0 | 0 | - | |
侏罗系上统遂宁组 | 49 | 0.797644 | 5 | |
侏罗系中统下沙溪庙组 | 22 | -0.309074 | - | |
侏罗系中下统自流井组 | 5 | -0.961061 | - | |
植被(NDVI) | -1~0 | 176 | 0.132877 | 21 |
0~0.2 | 11 | -1.164542 | - | |
0.2~0.4 | 9 | 0.353476 | 18 | |
0.4~1.0 | 0 | 0 | - | |
降雨量(mm) | 0.0~1.0 | 65 | 0.568849 | 10 |
1.0~2.0 | 43 | 0.453245 | 14 | |
2.0~3.0 | 80 | 0.572047 | 9 | |
>3.0 | 8 | -0.003276 | - |
Fig. 10 Geological hazard risk distribution map图10 地质灾害易发性评价分区图 |
Tab. 3 Comparison of risk zones and geological hazards sites表3 危险性等级分布表 |
易发性等级 | 该级别面积(km2) | 占研究区面积比(%)(a) | 灾害点个数 | 占灾害点总数比(%)(b) | 灾积比(b/a) |
---|---|---|---|---|---|
低 | 449.617 | 15.27 | 3 | 1.5 | 0.09 |
较低 | 666.110 | 22.62 | 12 | 6.3 | 0.27 |
中 | 895.299 | 30.41 | 21 | 10.8 | 0.36 |
较高 | 648.251 | 21.97 | 56 | 28.7 | 1.31 |
高 | 286.582 | 9.73 | 104 | 52.7 | 5.42 |
Fig.11 Success-rate ROC curve and prediction-rate ROC curve图11 成功率ROC曲线和预测率ROC曲线 |
The authors have declared that no competing interests exist.
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[4] |
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[5] |
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[6] |
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[7] |
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[8] |
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[9] |
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[10] |
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[11] |
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[12] |
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[13] |
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[14] |
|
[15] |
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[16] |
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[17] |
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[18] |
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[19] |
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[20] |
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[21] |
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