基于景观格局与生态过程的土地整理生态效应评价——以天津市七里海镇为例

EVALUATION OF ECOLOGICAL BENEFITS OF LAND ARRANGEMENT PROJECTS BASED ON LANDSCAPEPATTERN AND ECOLOGICAL PROCESS: A CASE STUDY IN QILIHAI TOWN OF TIANJIN CITY

关键词:  景观格局 生态过程 土地整理 生态效应

Key words:  landscape pattern  ecological process  land arrangement  ecological effect

摘要:

目前，对土地整理项目效益的评价多集中关注于经济效益评价，对生态效应的评价较少，更没有将评价结果应用于土地整理项目的规划设计和实施中。该文从生态系统结构的整体出发，结合宏观的景观格局与微观的生态过程，选取了斑块个数、破碎化指数、景观隔离度、植被覆盖率、生物多样性指数、物质循环速率、干扰频率和土壤质量8个二级评价指标，构建了土地整理项目的生态效应评价体系，运用归一化方法对评价指标量化，并结合天津市七里海镇土地整理项目进行实证研究，结果表明该土地整理项目在景观格局方面得到了较好的优化，斑块个数减少，破碎化指数降低，总体景观隔离度降低，但局部区域由于修建水泥道路导致隔离度增加。在生态过程方面，植被覆盖率提高，但呈现季节性，生物多样性降低，物质循环速率和干扰频率增加，土壤质量有较大提高。总体上，土地整理项目取得了耕地面积和土壤质量改善方面较好的效益，但在生态系统方面受到较大干扰，带来了负效应。今后需要在土地整理项目中从生态学角度进行规划设计，以取得经济、社会和生态综合效益。

Abstract:

At present, evaluation of land consolidation project benefit more focused on evaluation of economic benefit, fewer on evaluation of ecological effect, and none of the results of the evaluation was applied to the land consolidation project's planning ,design and implementation. From the overall structure of the ecological system, and combining macro landscape patterns and micro ecological process, selected the number of patches, landscape fragmentation, landscape isolation degree, vegetation coverage, biological diversity index, material circulation rate, interference frequency and soil quality, and then constructed the ecological effect evaluation system of land arrangement. Using the normalized method to quantify the evaluation index, an empirical study of land consolidation project was carried out in Qilihai town of Tianjin, and the results showed that the land arrangement in landscape pattern has been better optimization; the number of patches decreased, the landscape fragmentation reduced, and the overall landscape isolation degree was reduced except local regional isolation increases due to the construction of the cement road. In the ecological process, vegetation coverage rate increased seasonally, biodiversity reduced, material recycling rate and frequency increased; the soil quality improved greatly. Overall, the land consolidation project made better benefit in arable land and soil quality improvement, but the ecosystem was disturbed greatly and got negative effects. In the future, the land consolidation project should be planed and designed from the ecological point of view, in order to achieve economic, social and ecological comprehensive benefits.