江苏省景观生态风险评估及其与城镇化的动态响应

【目的】 评估景观生态风险,探明其与城镇化的动态响应,为江苏省科学调控高水平生态环境保护和高质量城镇化发展提供依据。【方法】 选用2010年Landsat TM和2018年Landsat OLI遥感影像数据,借助ENVI 5.3、ArcGIS 10.2软件,通过景观格局指数分析景观格局变化,综合评估景观生态风险并探讨其层级结构特征,定量测度景观生态风险与城镇化两者“增量”的响应类型及相关关系。【结果】 江苏省主要景观为耕地、建设用地和水域,其中耕地是基质景观。在景观格局演变中,耕地的异质性增强,建设用地以外部扩张为主,水域基本不变。景观生态风险提升显著,均值由0.123 6上升至0.149 9,现状景观生态风险TOP3城市为苏州、无锡和常州;景观生态风险自北向南逐渐升高,集聚分布态势和经济指向性趋势明显。景观生态风险与城镇化水平“增量”的耦合度大于0.8,城市建设用地快速扩张对景观生态风险快速上升的贡献度高,正向相关系数高达0.83。【结论】 江苏省景观格局变化显著,景观生态风险与城镇化水平同向提升、高度耦合。动态响应类型包括徐州、宿迁、盐城、淮安和扬州构成的低敏感区、沿江地区和连云港构成的中敏感区、苏州和无锡构成的高敏感区。苏南5市和南通“摊大饼式”土地城镇化发展迅速,经济发展水平高的苏南地区是景观生态高风险区域,土地城镇化会加速生态环境恶化,而人口城镇化会缓冲恶化速度,经济结构的转变影响式微。

Assessment of landscape ecological risk and its dynamic response with urbanization development of Jiangsu Province

【Objective】 This paper assessed landscape ecological risk and explored the response with urbanization, aiming to provide the basis for Jiangsu’s scientific regulation and control of high-level ecological environment protection and high-quality development of urbanization. 【Method】 Using remote sensing image data of Landsat TM of 2010 and Landsat OLI of 2018, and with help of ENVI 5.3 and ArcGIS 10.2, we analyzed changes in landscape pattern through landscape pattern indices, made comprehensive assessment of landscape ecological risk and probes into hierarchical structure and its characters, and made quantitative measurement of response type and dependency relationship between increment of both landscape ecological risk and urbanization. 【Result】 Jiangsu’s main landscape types included cultivated land, built-up land and water, with cultivated land as base landscape. In the evolution of landscape pattern, cultivated land’s heterogeneity increases, built-up land was mainly used for external expansion, and water basically remained the same. Landscape ecological risk increased significantly, and average value raised from 0.123 6 to 0.149 9. The TOP 3 cities of current landscape ecological risk were Suzhou, Wuxi and Changzhou, and the high risk area was located in southern Jiangsu while the low risk area lied in northern Jiangsu. The value of landscape ecological risk increased gradually from northern Jiangsu to southern Jiangsu with the passage of time. There were distinctive characters of agglomeration distribution situation and economic development tendency. Coupling degrees of incremental landscape ecological risk and incremental urbanization level were greater than 0.8. Built-up urban land expansion came up with a great contribution rate to increment of landscape ecological risk. And the correlation coefficient reached 0.83. 【Conclusion】 Jiangsu’s landscape pattern changed significantly. Landscape ecological risk and urbanization level displayed the response pattern of homodromous ascending and their increments were high coupling. Dynamic response types contained low-sensitive region of Xuzhou, Suqian, Huai’an and Yancheng in northern Jiangsu and Yangzhou, mid-sensitive region of area along the Yangtze River and Lianyungang, high-sensitive region of Suzhou and Wuxi. Land urbanization of “spreading out the pies” type developed rapidly in five cities of southern Jiangsu and Nantong City. Southern Jiangsu area of high-level economic development was with high landscape ecological risk. Land urbanization would accelerate ecological environment degradation, while population urbanization could slow down the deterioration rate, and economic restructuring made less disturbance.