沱江流域生态安全预警及其生态调控对策

Ecological Security Early-Warning and Its Ecological Regulatory Countermeasures in the Tuojiang River Basin

从沱江流域生态安全预警入手,基于压力-状态-响应(pressure status response,PSR)模型构建生态安全评价指标体系,采用层次分析、时间序列预测、模糊综合评判、主成分分析方法对流域2010、2015、2020年的生态安全状态进行评价与预警研究。结果表明:(1)沱江流域各区段在2010、2015、2020年3个时段内,整体上呈现全流域生态安全跃升的趋势,生态安全状态逐步好转;(2)纵观2010-2020年期间流域内各区段的生态安全变化,上游区段的生态安全状态明显好于中下游区段,其次为中游区段,下游区段的生态安全状态最为令人担忧。因此,沱江下游是流域内生态安全建设的重点;(3)沱江流域2010-2020年生态安全预警分为3类:安全区域、持续危险区域和退化区域。安全区域包括沱江上、中、下游的21个市县区;持续危险区域涵盖了中、下游的8个县区;退化区域为中游的2个县;(4)沱江流域生态安全预警的主要预警因子可以归纳为植被覆盖与农业灾害因子、人口素质因子、土地承载力因子、景观格局因子、面源污染因子、水土流失因子6大类。针对沱江流域生态安全预警因子的分析结果,提出以下生态调控对策:(1)积极修复植被,改善生态环境;(2)增强农业的防灾减灾能力;(3)加强技能培训,提高人口素质;(4)合理利用土地资源,提高土地承载力;(5)优化土地利用结构,加大景观多样性;(6)提倡生物防治,控制面源污染;(7)大力进行水土保持建设。

Based on a pressure-status-response （PSR） model, an ecological security evaluation index system which consists of 15 selected items was established. The ecological security of the Tuojiaug River Basin in 2010, 2015 and 2020 was predicted as early warning with the aid of the technologies of analytic hierarchy process（AHP） , chronological prediction, fuzzy integrated evaluation, and principal component analysis. Results show that （ 1 ） on the whole the ecological security of the basin will be getting better and better in the years of 2010, 2015 and 2020; （2） it will vary from section to section. It will be much better in the upper reaches than that in the middle and lower reaches, and in the middle reaches than in the lower reaches, so the lower reaches of the Tuojiang River Basin should be the major zone for concern; （3） in terms of mid-term ecological security early-warning, the basin can he sorted into three categories, i.e. safe region, consistently endangered region and degraded region. The safe region is composed of 21 counties （cities or districts） in the upper, middle and lower reaches, the endangered one, of 8 counties （cities or districts） in the middle and lower reaches; and degraded one, of 2 counties only in the middle reaches; and （4） the main factors for early-warning of ecological security in the period of 2010-2020 in the studied area can he concluded as six categories, i.e. vegetation coverage and agricultural disasters, rural population quality, land loading capacity, land use patterns, non-point source pollution, and soil erosion. Based on the findings in the study, the following ecological regulatory countermeasures are put forth ： （ 1 ） to restore vegetation and improve eco-environment ; （ 2 ） to enhance the capacity of the agriculture on preventing and standing natural disasters ; （ 3 ） to strengthen skill training of the labor force and improve quality of the population ; （4） to rationalize exploitation of the land resources and raise loading capacity of the land; （5） to optimize land use structure and increase landscape diversity ; （6） to advocate biological control of pest, and control non-point source pollution ; （7） to develop soil and water conservation projects.