湿地退化标准的探讨

湿地退化是自然环境变化和人类不合理利用导致的湿地生态系统结构破坏、功能衰退、多样性减少、生产力下降等一系列生态环境恶化的现象。我国湿地退化现象严重，恢复和重建工作紧迫。湿地退化标准的制定是一项基础工作．它应包括湿地面积变化、组织结构状况、湿地功能、社会价值、物质能量平衡、持续发展能力、外界胁迫压力等方面。与恢复重建相联系将退化湿地分为4个等级，分别对应不同的恢复重建策略。

Discussion on Standard of Wetland Degradation

Wetland is a special ecosystem, which is located in the zone of interaction between land and water. It's very important to both of environment and human, and is one of the three life-sustained systems with forest and ocean. Wetland degradation would directly affect eco-environmental change, social progress and economic sustainable-development. It is a series of phenomenon of ecosystem deterioration, such as structure destroying, function decaying, diversity decreasing, productivity declining, and so on, that caused by natural environment changes and irrational human activities. The phenomenon is serious in China, and it has been endangering eco-environmental evolution, social progress and economic development, so setting about a project of restoration-creation of degradation wetland is imperative. So far, a number of restoration-creation projects have put in practice, but their expected effects is unclear. It is a basic work that formulates a standard of wetland degradation, and it would provide decision-making basis for assessment of wetland and restoration-creation projects of degradation wetlands. Drafting the standard should keep to some principles, including representative, quantification, universality, realizable and availability. The standard should include of change of wetland acreage, structure status, function, social value, balance of matter and energy, ability of sustainable development, outside pressure, etc. Taking the relation of different degradation wetland and restoration-creation into account, the paper divides four grades of degradation wetland, that is non-degradation, slight degradation, serious degradation and extreme degradation. For different degradation grade, the wetland has different policy of restoration-creation respectively. The non-degradation wetland is a healthy ecosystem which can be suited to exploitation; the slight degradation wetland, which could restore naturally, is mainly preserved; the serious degradation wetland hasn't been developed by itself and need some engineering measurements to impel it to restore; the extreme degradation wetland, the last grade one, has been destroyed completely and only one approach will adopt to create a new ecosystem according to the new surroundings.