大连市生态脆弱性评价及其不确定性分析

目的]分析大连市生态脆弱性总体结果和空间分布特征,并识别分析评价体系的敏感性特征。方法]基于生态敏感性—生态恢复力—生态压力度(SRP模型)构建城市生态脆弱性指标体系评估模型;采用OAT(one-at-a-time)方法评估指标权重不确定性下的结果变异程度。结果]大连市极度脆弱、重度脆弱、中度脆弱、轻度脆弱、微度脆弱5个等级面积比例分别是4.17%,22.97%,41.00%,23.69%,8.16%;脆弱性最高的地区位于市中心及甘井子区东部,脆弱性最低的地区位于大连市北部地区、甘井子区与旅顺区交界处。土壤有机碳含量指标对结果影响最大,区域绝对平均变化率的最大值及最大像元变化率分别为11.49%和17.27%。结论]大连市整体生态脆弱性处于中等脆弱水平,对于土壤有机碳含量指标权重应慎重考虑以减少评估结果不确定性。

Ecological Vulnerability Assessment and Its Uncertainty Analysis of Dalian City

Objective] The objectives of the study were to analyze the overall spatial distribution characteristics of the ecological vulnerability of Dalian City and identify the sensitivity characteristics of the evaluation index system.Methods] We constructed an urban ecological vulnerability index system based on sensitivity-recovery-pressure model (SRP), and the one-at-a-time method (OAT) was used to estimate the sensitivity of results under uncertainty of index weights.Results] The vulnerability of Dalian City was classified into five levels:extreme vulnerability, high vulnerability, moderate vulnerability, light vulnerability and slight vulnerability, with an area proportion of 4.17%, 22.97%, 41.00%, 23.69%, and 8.16%, respectively. The areas with the highest vulnerability distributed in the city center and the east area of Ganjingzi District, while areas with the lowest vulnerability distributed in the northern part of Dalian and the junction of Ganjingzi District and Lushun District. The soil organic carbon showed the greatest impact on the evaluation results. The maximum absolute average change rate and the maximum pixel change rate was 11.49% and 17.27%, respectively.Conclusion] The overall ecological vulnerability of Dalian City is at a moderate vulnerability level. The weight of soil organic carbon index should be carefully considered to reduce the uncertainty of evaluation results.