苏州市吴中区生态环境质量现状定量评估与分析

摘要

Eco-environment is the foundation of human and the development of society and economy. Rapid economic growth improves the people's living standard, but brings some negative effects on the environment. To better understand the impacts of economic development on the eco-environment of city and rural, in this study, the ecological carrying capacity, land use and change, vegetation net primary productivity (NPP) and ecological factor index were selected as indexes to evaluate and analyze of eco-environmental quality of Wuzhong District of Suzhou. The results showed that (1) the ecological carrying capacity of Wuzhong were 0.273 4~0.104 4 hm2, which appeared to be the ecological deficit obviously. In 2005—2012, the ecological carrying capacity, ecological footprint and ecological deficit decreased by 62%, 48% and 46%, respectively. However, in the terms of the ecological footprint and carrying capacity, the ecological deficit was still serious. (2) In 2000—2013, the average vegetation NPP of Wuzhong decreased by 0.12 g·m-2 (C), and the total carbon sequestration storage decreased by 0.8 × 109 g·a-1(C), which implies that the carbon sequestration capacity and productivity of ecosystems in Wuzhong have been declining. (3) In 2000—2013, 406.41 km2 of land cover changed, 139.53 km2 of lands changed into artificial land, which are mainly from farmland, vegetation and paddy lands with 76.16, 30.01 and 24.25 km 2,respectively. (4) Natural ecological green area was increasing, but the vegetation thickness, ecological capacity and the amount of carbon sequestration decreased, which showed a deterioration of the eco-environmental quality of Wuzhong. In conclusion, the eco-environmental quality and the relationship between protection and development of Wuzhong have been becoming worse in 2000—2013.%生态环境是人类生存及社会经济持续发展的基础,经济的快速增长有效提高了人民生活水平,但同时对生态环境也造成了一定的影响. 为了更好地了解经济发展和城市化对城市生态环境的影响程度,定量评估其影响水平,以苏州市吴中区为研究对象,选取生态承载力、土地利用变化、植被净初级生产力(NPP)和生态因子指数等4个指标对苏州市吴中区的生态环境质量进行定量评估和分析. 结果表明:(1) 苏州市吴中区人均生态承载力为0.273 4~0.104 4 hm2, 表现出较为明显的生态赤字. 在2005—2012年间,人均生态承载力、生态足迹和生态赤字分别下降62%,48%和46%,但从生态足迹和承载力来看,生态赤字现象仍较为严重.(2)2000—2013年间,苏州市吴中区植被NPP平均值以C计减少了0.12 g·m-2,固碳总量减少了0.8×109 g·a-1,表明吴中地区各类生态系统的固碳能力和生产能力呈现下降趋势.(3)2000—2013年间,苏州市吴中区共有406.41 km2土地覆被发生转化. 其中,共有139.53 km2土地转化成人工表面,主要来源于农田、植被和水田,转化面积分别为76.16,30.01和24.25 km2.(4)虽然吴中区自然生态绿化面积在增加,但植被厚度、生物多样性、生态能力和碳汇量在减少,其生态环境质量呈变差趋势.因此,最终结果是吴中区因受到经济开发和城市化的影响较大及生态保护措施不利,近10年来其总体生态环境质量呈下降趋势,其发展与保护的矛盾仍很尖锐.