快速城市化地区塘的消减过程研究——以广州市天河区为例

The Disappearance and reduction process of ponds in rapid urbanization area:Tianhe district,Guangzhou city as a case

塘是我国南方地区常见的、分布广泛的景观类型,也是相对独立的水生生态系统,在生态系统服务和人类经济文化活动中扮演着非常重要的角色。国际学者对其在保护生物多样性、防涝排水、提升景观及改善人居环境等方面的生态功能研究较多,但国内对塘的形成、消减过程、生态环境功能效应等科学问题一直认识不足,在人口和土地的快速城市化胁迫下,为了增加建设用地使用面积而将水塘填埋的行为广泛存在。文章以广州市天河区为研究区,以1996、2000、2004、2007、2011年5期遥感影像为数据,通过目视解译获取研究区的土地利用特征,提取水塘信息,依据塘的主要功能对塘进行分类,通过缓冲区分析、主成份分析和转移矩阵分析探索快速城市化地区水塘消减过程的数量和空间分布特征。结果表明:(1)研究区内水塘景观在15 a间显著消减,数量由109个减至20个,面积由36.30 hm2降至13.18 hm2,个体减少率为81.65%,面积减少率为63.69%;(2)不同时段、不同功能类型的水塘消减过程存在明显差异,养殖塘、风水塘、山塘和灌溉塘面积急剧减少,景观塘面积先降后增;(3)各时段的塘转换主要去向为居住用地、商业及工矿用地等,周边土地利用格局有交通用地、荒草地的塘更易于被转换成建设用地等其他土地利用类型;(4)在城市人居环境建设中,水塘具有保持生物多样性、调节气温、改善气候、防旱排涝、改善人居环境等生态价值,又具有历史文化、景观美化等人文价值,但水塘已成为快速城市化地区居住、商业、工矿用地的主要侵占对象。作为冷岛的水塘生态系统,在城市化进程和各项规划中都应受到重视与保护。

The pond is a very common landscape in south China, also a kind of relatively independent ecological system, which is playing a important role in the ecosystem services and economic, cultural activities. International scholars mainly study the major functionsof pond manifest in biodiversity conservation, drainage-prevention of water logging, geomancy landscaping and＆amp;nbsp;improvement to the living environment. But the question of the formation, the eco-environmental effect and the disappearance and reduction process of ponds has been lacking of recognition for too long, in China, the phenomenon of filling pond for increase area of construction land occurs widely during the fast urbanization. This paper took Tianhe District in Guangzhou City as the research object, obtained Landscape pattern characteristics by interpreting remote sensing data of terms （1996, 2000, 2004, 2007 and 2011）, extracted information of ponds, classified according to main functions, explored the distribution of quantity and space of disappearance and reduction process of ponds, through the analysis of buffer, principal component and transfer matrix. Our results demonstrated that： （1） during 15 years, the area of ponds remarkably reduced by as much as 63.70 percent： from 36. 3 0 hm2 to 13.1 8 hm2. （2） There’s an obvious difference at different stages and with different types of ponds. The area of aquaculture ponds, geomancy ponds, pool-ponds and irrigation ponds declines sharply or even disappears, the area of landscape ponds expand after a decline during the recession. （3） At different stages ,most of the pond converted into residential land, commercial-industrial land, if the pond is surrounded by some special land use patterns such as transportation land and grassland ,it is more likely to transfer into other land use types.（4） During the construction of habitat environment, the pond has important ecological and humane value, such as biodiversity conservation, regulating temperature, improves the microclimate,drainage-prevention of water logging, improvement to the living environment, historical culture, landscaping, etc. But in rapid urbanization areas, ponds have become the main occupancy object of residential land and commercial-industrial land. As a cold-island effect ecosystem, ponds deserve a serious look and protected in the process of city development and the planning.