【作者】 章飞军；

【导师】 陆健健；

【作者基本信息】 华东师范大学 ， 生态学， 2007， 博士

【摘要】 能量是所有开放系统生存和演化的必要条件，是生态系统代谢的通用“货币”。从能量入手，容易在生态系统复杂性研究上获得突破。能量学的方法运用于复杂的生态系统研究已成为当前和未来生态学研究的一个重要方向。本文在国内首次在长江河口湿地生态系统研究中应用“埃三极”（Exergy）理论，主要目的在于对生态系统的状态和变化进行量化探索，使得复杂的生态系统研究更加有效准确。本文主要研究成果如下：（1）基于生物量和生物复杂性信息的Exergy分析非常直观地反映出长江河口大型底栖动物群落的复杂性状况。Exergy计算比生物量、丰度分析更具系统性和综合性。（2）综合分析受干扰后大型底栖动物群落演替得出干扰的空间尺度决定了群落的恢复特征，如果干扰区域明显小于周边未受干扰的区域，那么群落的复杂性（信息量和网络结构）将先于生物量得到恢复。（3）而Exergy作为一种生态监测指标的研究表明该指标不但适用于干扰后底栖动物群落恢复过程的监测，而且适合更广泛的生物系统研究。用周边对照区作为计算受干扰群落的局域Exergy值的动态参考比用历史资料更合适。（1）Exergy指标用于长江口潮下带大型底栖动物群落结构分析2005年4月对长江口全区域潮下带共10个采样站位的大型底栖动物进行了调查。分析了其种类组成、丰度、生物量现状及相关环境因子的作用，阐明了其空间分布格局，并应用Exergy理论分析了不同空间格局下的底栖动物群落所处的状态。本次调查采获大型底栖动物38种，分属5个生态类型，种类数以河口外缘的顾圆沙附近的10号站位和九段沙下沙附近的1号站位较多，分别为23种和12种，口内站位均未超过10种。各站位大型底栖动物的平均丰度为32.9个／m²、平均生物量为5.035g／m²（湿重）；各站位的平均生物量仅为5.035g／m²（湿重），大大低于1988年同期（5月）的平均生物量24.2 g／m²；口外缘站位的总丰度和总生物量均高于口内站位，表现为九段沙下沙附近的1号站位和中沙附近的2号站位的大型底栖动物丰度较大，分别为80 ind.／m²和70ind.／m²。其余8个站位的的丰度则均小于50ind.／m²，其中尤其以白茆沙附近的8号站位和新村沙附近的9号站位最小，仅为4ind.／m²。生物量分布则以九段沙附近1、2号，东风西沙附近的7号和新村沙附近的9号站位较高，其他站位相对较低，其中尤其以白茆沙附近的8号站位最低，仅为0.048 g／m²（干重）。环境因子相关分析（R＝0.924，P＜0.05）表明盐度是决定长江口大型底栖动物种类分布最重要的环境因子。群落聚类、标序分析显示，春季长江口潮下带大型底栖动物群落结构空间分异明显，完全符合目前长江口支、港、槽“三级分汊”的空间格局。Exergy分析可以得出长江河口底栖动物群落的复杂性状况为北支(EX_A=4582.25 J m^-2)优于南支(EX_B=1071.228 J m^-2、Ex_c=11.58 J m^-2、EX_D=1751.81 J m^-2)，口外(EX_D=1751.81 J m^-2)优于口内(EX_B=1071.228 J m^-2、Ex_c=11.58 J m^-2)，这与生物量和丰度分析结果一致，也就是说基于生物量和生物复杂性信息的Exergy可以非常直观的反映出长江河口大型底栖动物群落的复杂性状况。同时可以看到Exergy计算比生物量、丰度分析更加简洁，而且Exergy分析更具系统性和综合性。（2）用于河口潮滩湿地大型底栖动物群落演替分析2006年1月在崇明岛西端的潮间带湿地进行了一项生态工程，经过土方工程的区域被选为大型底栖动物群落的演替区，因为其中的大型底栖动物群落受到了较大的破坏，在其周边未受干扰区设立对照样点。本研究试图通过群落重建群的研究分析三个问题：（1）在群落恢复过程中不同的生态学指标是如何变化的?（2）群落演替过程中什么先增长，生物量还是复杂性?（3）是否可以选择生态学指标以利于演替过程中三类不同的增长模式（生物量、网络结构和信息量）的识别?多变量分析用于检验被干扰区群落是否已经得到恢复。Shannon-Wiener指数、Margalef指数、Pielou均匀度指数、生态“埃三极”（Eco-Exergy）和结构“埃三极”（Specific Eco-Exergy）用于分析演替过程中群落状态的变化。结果显示物种随时间的更替与群落结构的变化密切相关。物种丰富度增长迅速，而且对照区和演替区的物种组成非常相似。演替进行1个月左右之后，演替区的生物多样性已经超过了对照区。生态“埃三极”和结构“埃三极”提供了群落结构发展的有用信息，但仍然缺乏鉴别系统所处信息状态的能力。多样性分析结果可以从中度干扰假说（Imermediate Disturbance Hypothesis）得到很好的解释。总体而言，干扰的空间尺度决定了群落的恢复特征，如果干扰区域明显小于周边未受干扰的区域，那么群落的复杂性（信息量和网络结构）将先于生物量得到恢复。（3）用于河口潮滩湿地生态建设过程监测分析Exergy作为热力学指标是指系统从给定状态到与其周围介质达到热力学平衡所需做的最大功，Exergy概念被生态学家借鉴应用于生态系统的研究，使它有了生物学的含义。应用Exergy作为生态指标，用于指示崇西潮滩湿地生态工程中受到干扰的大型底栖动物群落结构的复杂的恢复过程。用BACI（beforeversus after.control versus impact）方法进行底栖动物采样，根据（a）不同食性类群的代码基因数；（b）储存在有机体基因内的信息；（c）种水平上的基因组尺度（C值）作为参数估算局域Exergy。结果显示工程区的Exergy值在工程干扰后9d时降到最低，接着工程区大型底栖动物群落的Exergy值逐渐与周围对照区趋向平衡。270d后，工程区的大型底栖动物群落得到恢复。3种不同方法估算的区域Exergy值表现出极为相似的动态趋势，进一步证实了用基因组尺度数据估算Exergy的可行性和优越性。研究表明Exergy指标不但适用于干扰后底栖动物群落恢复过程的监测，而且适合更广泛的生物系统研究。用周边对照区作为计算受干扰群落的局域Exergy值的动态参考比用历史资料更合适。更多还原

【Abstract】 Application of the energy methods as an indicator in the complexity of the ecosystem is a significant trend. Because energy is the essential term of the ecosystem, further more it is an universal "money". From the enery launching on, it’s easy to obtaining breakthrough at the complexity study of the ecosystem. In this paper, Exergy indicator applicated in three aspects of the esturine wetland ecology study. The main conclusions as following: First, State about the health of the macrobenthic ecosystem: North branch was better than south branch, outside was better than inside. The conclusions showed that exergy analyzing was better than analyzing of biomass or abundance. Second, the characteristics of a systems’ recovery after disturbance appeared to be dependent on the spatial scale of the disturbance. If a disturbed area was small when compared to a contiguous non-disturbed one, complexity （information and network） would recover prior to biomass. Third, we discussed the feasibility of using the more available genome size data set for estimating exergy and the broader implications of using this indicator in other biological systems. Exergy was demonstrated to be a useful indicator that integrated the processes underlying the recovery of the benthic community after disturbance.（1） Exergy was used to analyze macrobenthic fauna community in the Yangzi estuarySamples of subtidal macrobenthic fauna were collected and environmental factors were measured in the Yangtze Estuary in April, 2005. The community structure of macrobenthic fauna and its correlation with environmental factors were analyzed. Exergy as an indicator used to analyze the state of the macrobenthic ecosystem. Thirty-eight species were identified, belonging to five ecological assemblages. The total number of species was low, but was higher in the outer sampling sites of the estuary. The average abundance was 32.9 ind·m^-2 and the average biomass was 5.035 g·m^-2（fresh weight） at all sampling stations. Compared with historic data from the 1970s and 1980s, the community structure of macrobenthic fauna has changed obviously and the biomass has decreased rapidly. Total abundance and biomass of the species were obviously higher in the outer sampling sites of the estuary. Salinity was the main factor affecting the distribution of the macrobenthic fauna. The Bray-Curtis Cluster analysis showed that the macrobenthic fauna at all sampling station had four assemblages, which accorded with three spatial structural grads of the Yangtze River Estuary.State about the health of the macrobenthic ecosystem: North branch is better than south branch, outside was better than inside.（2） Ecological indicators performance during a re-colonisation field experiment and its compliance with ecosystem theoriesThe study was carried out in an intertidal flat after ecological engineering at the west of the Chongming Island in January, 2006. Succession plots were disturbed by ecological engineering and macrobenthos community were damaged severely. Through a re-colonisation field study three main questions were approached: （1） How do different ecological indicators react during the process of recovery? （2） What does grow first during a community succession, biomass or complexity? （3） Can the chosen ecological indicators help in recognising the three proposed forms of growth: biomass, network and information, throughout re-colonisation? Multivariate analysis was performed to examine the convergence of the disturbed plots with the surrounding community during recovery. Shannon-Wiener Index, Margalef Index, Pielou evenness, Eco-Exergy and Specific Eco-Exergy were applied to characterise the state of the community during the process. Results showed that the replacement of species over time happened associated macrobenthos community. Species richness increased rather rapidly and species composition was similar in disturbed and undisturbed areas. After 1 month, diversity was consistently higher in the community undertaking recovery. Eco-Exergy and Specific Eco-Exergy provided useful information about the structural development of the community but lacked discriminating power with regard to the informational status of the system. The observations appear to illustrate a case explainable by the Intermediate Disturbance Hypothesis （IDH）. Overall, the characteristics of a systems’ recovery after disturbance appear to be dependent on the spatial scale of the disturbance. If a disturbed area is small when compared to a contiguous non-disturbed one, complexity （information and network） will recover prior to biomass.（3） Application of exergy as an indicator in the restoration of ecosystemThermodynamic function exergy, which represents the distance of an open system from equilibrium, is proposed as an ecological indicator for summarizing the complex dynamics occurring in a disturbed community during the recovery processes. This quantity has been difficult to capture using classical indices. Exergy storage is estimated for benthic communities in response to experimental disturbance, as induced by ecological engineering, at the Chongxi tidal wetland of Chongming Island. exergy storage was sampled using the BACI scheme （before versus after, control versus impact）. The control area is proposed as a dynamic reference for estimating the local exergy storage of the benthic community. Three different methods were used for estimating exergy on the basis of coefficients: （a） taken from trophic groups, （b） estimated from coding genes for broad taxonomical groups and （c） estimated from genome size and taken as close as possible to the taxonomical level of the species, providing a basis for inferring upon their similarities. The results show a decrease of local exergy content in the disturbed area, with a minimum in the area exposed to the engineering 1 month after the experimental disturbance. Subsequently, the exergy of the benthic community increased to the reference level, i.e., the surrounding control area, in accordance with the proposed hypothesis on the dynamics of exergy storage during a system’s development. Moreover, the adjacent control samples represented an appropriate dynamic reference for estimating the local exergy of the experimentally disturbed community. The three methods for estimating the local exergy values provided comparable results. Therefore, we discuss the feasibility of using the more available genome size data set for estimating exergy and the broader implications of using this indicator in other biological systems. Exergy was demonstrated to be a useful indicator that integrates the processes underlying the recovery of the benthic community after disturbance.更多还原