农林复合流域非点源污染调控的景观生态学研究现状

A Landscape Ecological Approach for the Control of Non-point Source Pollution Exported from Agroforestry Watershed

农业生产活动产生的非点源污染已成为三峡库区等农林复合流域较为严重的生态环境问题。景观生态学强调景观格局对生态过程中物质流、能量流的控制和影响。本研究以三峡库区农林复合流域为研究对象,从斑块类型水平、景观水平,综述非点源污染调控的景观生态学途径研究进展:第一阶段为景观生态调查。了解流域景观格局特征,判定造成非点源污染的主要原因和关键环节,明晰非点源污染产生的"源"斑块及其生态过程,确定景观格局与非点源污染的反馈关系;第二阶段为景观生态规划。斑块水平上,选取最佳管理措施(BMPs),评定应用效果;景观水平上,增加新的景观要素,调整"源"、"汇"景观斑块类型,评估景观水平调控效果;第三阶段景观生态管理。从斑块和景观两种水平进行小流域景观生态建设,逐步实施BMPs,实现景观生态规划与管理的有机结合,增强景观异质性,有效控制非点源污染强度,达到小流域的可持续发展。

Non-point source （NPS） water pollution generated by agricultural production is considered as a major environmental issue in China. Landscape ecology emphasizes the regulation and effect of landscape pattern on material flow, energy flow through ecological processes. In this study, landscape ecological approach for non-point source pollution control was discussed on patch class-level and landscape-level under the Three Gorges Reservoir agroforestry watershed conditions. The first was landscape ecological investigation. It was understanding the characteristics of watershed landscape pattern, realizing the main reason and key process for non-point source pollution, understanding the ＂source patches＂ of NSP and its ecological processes, and defining the feedback between landscape spatial pattern and non-point source pollution. The second was landscape ecological planning. BMPs were selected and assessed on patch-level. New landscape elements was added. The ＂source＂and ＂sink＂ landscape patches were adjusted and assessed on landscape-level. The third was landscape ecological management. It included constructing watershed landscape on patch- and landscape-level, gradually implementing BMPs, combining landscape planning and management, enhancing landscape heterogeneity, controlling non-point source pollution intensity effectively, and achieving the sustainable development of small watershed.