| Popis: |
In order to understand the possibility and spatial pattern of Benggang (collapsing hill) erosion in risk assessment and distinguish the primary and secondary areas in Benggang prevention, we took a small watershed in Anxi County (Fujian, China) as the study area and Benggang as the source, and constructed the Benggang expansion resistance surface using the minimum cumulative resistance (MCR) model and divided the risk zoning. The results showed that the area around Benggang displayed a low resistance value, while the northwest and southeast areas displayed a high resistance value. The Benggang expansion resistance surface had an island type form. Based on resistance surface, the research region was divided into very high-risk, high-risk, medium risk, low-risk and very low-risk zones. We proposed corresponding Benggang management suggestions for those zones. A total of 21 strategic saddle points were extracted based on the resistance surface morphology. The strategic points in the lower safety zone were considered as the priority areas for Benggang prevention. We compared the hazard results based on the MCR model and the information quantity method. These results were consistent in spatial distribution, indicating the reliability of the results of hazard zoning by the MCR model.为在风险评价中体现出崩岗侵蚀产生的可能性和空间趋势、分清崩岗防治中的主次区域,本研究以安溪县小流域为研究区,以崩岗为源地,通过最小累积阻力模型构建崩岗扩张阻力面并划分危险性分区。结果表明: 研究区内崩岗周围区域阻力值较低,西北部及东南部阻力值较高,崩岗扩张阻力面形态为岛屿型。依据阻力面将研究区域分为高危险区、较高危险区、中等危险区、较低危险区和低危险区,并由此提出相应的崩岗治理建议。基于阻力面形态提取出鞍部战略点共21个,较低安全区中战略点应作为预防崩岗重点区域。将基于最小累积阻力模型和信息量法的危险性结果进行比较,两者在空间分布态势上一致,证明通过最小累积阻力模型进行危险性分区的结果可靠。. |
