资源型城市土地生态安全评价——以大庆市为例

Evaluation on Land Ecological Security of the Resources Cities:A Case Study of Daqing City

大庆是我国著名的油田城市,经过近50年的油田开采,区域内草地三化严重,土壤有机质不断淋失,作业区内土地污染严重,植被覆盖度降低,土地生态环境恶化。从影响土地生态安全的自然、经济、社会3个方面出发构建大庆市土地生态安全评价体系,并采取熵权系数的方法确定各评价指标的权重,在此基础上,采用物元的方法对大庆市1990,1996,2000,2005年4个时段的土地生态安全情况进行评价,评价结果表明:①1990—2005年大庆市土地生态安全等级在逐步提高,但总体处在较低水平;②大庆市土地生态自然子系统的安全等级较低,而经济子系统的安全等级很高,说明由于油田的开采一方面带来了巨大的经济效益,另一方面对土地自然生态系统破坏较大;③大庆市土地生态的社会子系统相对稳定。

Daqing is famous oil field city in our country, undergoes oil field mining for nearly 50 years. In the Daqing city region, the lawn degradation, sand character, salt and alkali character are serious and the soil ulmin ceaselessly leaches out, land is polluted badly in the oil region, the vegetation coverage degree is lower, then land ecological security situation is stern. Setting up the land ecological security evaluating system of the Daqing City based on the influence of the land ecological security＇ s nature, the economy, the social three aspects on the foundation of qualitative analysis, and adopts the entropy scaling coefficient method to determine the weight of each evaluating index, and based on this, uses the matter-element model to evaluating land ecological security situations in Daqing City in 1990, 1996, 2000, 2005, the evaluating results indicates that ① from 1990 to 2005 land ecological security rank is enhancing gradually in Daqing City, but the whole situation is at the lower level ; ②land ecology natural subsystem＇ s security grade is lower in Daqing City, but the economical subsystem＇ s security grade is very high, this is because on the one hand oil field mining has brought the huge economic efficiency to Daqing City, on the other hand destroys the land natural ecosystem in the bigger extent in Daqing City ;③land ecology social subsystem is relative stable in Daqing City.