基于诊断学的生态系统健康评价

Abstract

现有的生态系统健康评价多数是运用以活力-组织-恢复力指标为基础的时间断点个案研究，导致现有跨越时间和空间的研究成果难以进行对比与整合，与学科发展的系统化和全球化趋势不相符。“活力-组织-恢复力”评价指标加和会导致重要信息损失，引入诊断学“问诊-体格检查-实验室检查-辅助检查”的方法整合指标体系。初步探讨利用系统的物质或能量折算为熵流并设置相关辅助指标以计量系统健康水平，总结分析判别步骤，基本能判别各种生态系统属于活力型不健康、结构型不健康、发育型健康和成熟型健康4种状态。借鉴相关水生生态系统能流的研究成果初步检验该方法的可行性，研究表明通过熵流及辅助指标的计算，所引用2个水生生态系统熵流值和系统太阳能利用率、消费和有序化潜力等特征，与生态系统健康现实情况较为相符。同时，利用诊断学方法也可以对生态系统研究中一些难以量化的描述性概念，比如入侵和适度干扰，进行的定量分析。;Current ecosystem health assessments are mostly based on testing and analyzing the vitality-organization-resilience indexes of some breakpoint cases, which makes it hard to compare or integrate different research results across time and space. These results have narrow range of applications and do not conform to the disciplinary development trends of globalization and systematization. As the summation of the vitality-organization-resilience index system may ignore some important information, this article introduces a four-step diagnostic method of interrogation-physical examination-laboratory tests-auxiliary examinations to integrate an index system for the assessment of ecosystems. The method tests the ecosystem health using the entropy flow as measuring standard converted from substances or energy. It also analyzes related auxiliary indexes in different steps. Using energy and weight to calculate energy flow of an ecosystem, the diagnostic method can be divided into four main steps. First, unhealthy or important ecosystems are inquired based on investigators' academic sensitivity. Then the physique of ecosystems are characterized by the entropy value, followed by laboratory analyses of biological information (<em>β</em>i) and quality features (<em>C</em>i). At last, auxiliary examination indexes are measured which provide series information related to vitality-structure of the ecosystems. The study showed that, by calculating the entropy flow and auxiliary indexes, various ecological systems can be distinguished into four dynamic states: unhealthy vitality type, unhealthy structure type, developing healthy type and mature healthy type. The data from three cited aquatic ecosystems, the South Lake, the Cedar Bog Lake and the Silver Spring, were used to analyze the strength of entropy flow, solar energy utilization rates, consumption and potential features of organization. The diagnostic results showed that the Silver Spring scored the highest and the Cedar Bog lake scored the lowest in physique. Considering the environmental conditions and ecological efficiency, the Cedar Bog lake had the lowest consumption and the highest ordering potential in the three ecosystems. Both in the subtropical area, the South Lake's ordering potential equals only to that of the Silver Spring, a spring water river, which indicated that the lake has structural problems, and the Silver Spring was adapted to the river hydraulic state of high consumption and low potential. The results conformed with reality well. Some ecosystem concepts, like invasion and moderate interference, are difficult to describe quantitatively. The diagnostic method can also serve as a preliminary quantitative analysis in the subtle academic field. Measuring by ecological entropy flow, the phenomena of disturbance, plant diseases, insect pests and the invasion have similar essence although they have different performances. The diagnostics provided a preliminary quantitative analysis for ecosystem health in combination with its background and the changing factors.