藏西北高寒草原生态资产价值评估

论文基于遥感估算的生态系统净初级生产力(NPP)和植被覆盖率,测算了1992、1995、2000和2006年4期藏西北高寒草原的生态资产价值,并分析了其时空分布规律。结果表明:藏西北地区生态资产在空间格局上由东南向西北逐渐减小。从生态资产构成来看,藏西北地区的生态资产主要体现在大气调节(45%)和涵养水源(40%)两方面,其次为生产有机物质的价值(11%),水土保持和营养物质循环所占比例较小。从生态资产变化趋势来看,藏西北地区生态资产总值由1992年的616.1×10⁸元增长到2006年的1 637.2×10⁸元,单位面积生态资产均值平均每年增加1.06×10⁴元/km²。考虑到多源遥感数据之间存在一定程度的不一致性以及遥感时间序列数据较短等原因,论文所反映的藏西北地区生态资产变化趋势可能比实际情况偏高,其结果还有待于进一步佐证。     

玛曲县土地利用/覆盖变化对区域生态系统服务价值的影响

运用GIS和遥感技术分析了玛曲县1975、1990和2005年的土地利用/覆盖特征,在此基础上使用生态价值系数(C)计算出该县生态系统服务价值.结果表明,该区域1975~2005年间生态系统服务价值从129.713亿元减少到123.961亿元,共损失5.75亿元,且损失量和损失幅度呈持续增加趋势;该区域生态系统服务价值中,废物处理价值最高,气候调节价值次之,原材料价值最低,且30年间各服务类型的价值均呈减小趋势;玛曲县1975、1990和2005年人均生态系统服务价值分别为58.96,42.80,29.51万元,表明玛曲县由于人口的增长,环境压力呈持续增大趋势.草地和湿地退化是导致该区域生态系统服务价值减少的主要原因.CS检验说明本研究所选C值较为合理.     

巢湖流域农田生态系统磷代谢分析

采用物质流分析方法,建立巢湖流域农业种植系统的静态磷代谢分析模型,结合统计数据和文献参数,估算了2008年巢湖流域农田生态系统排水含磷来源分配以及流域各县(市)农田生态系统排水的磷含量.结果表明,巢湖流域整个农田生态系统的排向水体的含磷总量为14125.1158t,其中化肥和还田畜禽粪便是巢湖流域农田生态系统磷输入的主要来源,其排入水体的含磷总量分别为37172.0944t和26230.2336t;而肥西县与合肥市辖区是农田种植对水环境影响最大的区域,其农田生态系统排水含磷总量分别为4077.6575t和2849.133t.     

Application of an evolutionary algorithm to the inverse parameter estimation of an individual-based model

Inverse parameter estimation of individual-based models (IBMs) is a research area which is still in its infancy, in a context where conventional statistical methods are not well suited to confront this type of models with data. In this paper, we propose an original evolutionary algorithm which is designed for the calibration of complex IBMs, i.e. characterized by high stochasticity, parameter uncertainty and numerous non-linear interactions between parameters and model output. Our algorithm corresponds to a variant of the population-based incremental learning (PBIL) genetic algorithm, with a specific “optimal individual” operator. The method is presented in detail and applied to the individual-based model OSMOSE. The performance of the algorithm is evaluated and estimated parameters are compared with an independent manual calibration. The results show that automated and convergent methods for inverse parameter estimation are a significant improvement to existing ad hoc methods for the calibration of IBMs.     

Obscuring Ecosystem Function with Application of the Ecosystem Services Concept

Abstract: Conservationists commonly have framed ecological concerns in economic terms to garner political support for conservation and to increase public interest in preserving global biodiversity. Beginning in the early 1980s, conservation biologists adapted neoliberal economics to reframe ecosystem functions and related biodiversity as ecosystem services to humanity. Despite the economic success of programs such as the Catskill/Delaware watershed management plan in the United States and the creation of global carbon exchanges, today's marketplace often fails to adequately protect biodiversity. We used a Marxist critique to explain one reason for this failure and to suggest a possible, if partial, response. Reframing ecosystem functions as economic services does not address the political problem of commodification. Just as it obscures the labor of human workers, commodification obscures the importance of the biota (ecosystem workers) and related abiotic factors that contribute to ecosystem functions. This erasure of work done by ecosystems impedes public understanding of biodiversity. Odum and Odum's radical suggestion to use the language of ecosystems (i.e., emergy or energy memory) to describe economies, rather than using the language of economics (i.e., services) to describe ecosystems, reverses this erasure of the ecosystem worker. Considering the current dominance of economic forces, however, implementing such solutions would require social changes similar in magnitude to those that occurred during the 1960s. Niklas Luhmann argues that such substantive, yet rapid, social change requires synergy among multiple societal function systems (i.e., economy, education, law, politics, religion, science), rather than reliance on a single social sphere, such as the economy. Explicitly presenting ecosystem services as discreet and incomplete aspects of ecosystem functions not only allows potential economic and environmental benefits associated with ecosystem services, but also enables the social and political changes required to ensure valuation of ecosystem functions and related biodiversity in ways beyond their measurement on an economic scale.     

EMERGY analysis for sustainability evaluation of the Baiyangdian wetland ecosystem in China

This study presents a quantitative and ecological benefit evaluation of the Baiyangdian wetland in China between the years 2000 and 2006. Methods of EMERGY analysis were applied to illustrate the wetland ecosystem, to evaluate the economic and environmental inputs and consequent yields, and to assess the sustainability of the Baiyangdian wetland. The indicators for the integrated ecological and economic system, such as EMERGY yield ratio (EYR) (7.51), EMERGY investment ratio (EIR) (4.52), environmental loading ratio (ELR) (2.92), EMERGY exchange ratio (0.41), and EMERGY sustainable indicator (ESI) (2.57) were calculated, compared, analyzed, and discussed. The non-renewable investment in Baiyangdian was greater than renewable investment, leading to the unsustainable development of the system. High EYR indicated that the Baiyangdian integrated system had created huge profits for its people, while ELR and ESI revealed that human behavior has been a heavy burden on the environment, and countermeasures should be taken by the Chinese government to relieve and resolve these problems. Potential management methods were also proposed in this paper.     

吴江市土地利用变化及其生态效应

利用1993、2000和2004年吴江市的遥感影像,在GIS和RS支持下,通过构建土地利用转移矩阵对土地利用变化进行分析,并对其产生的生态效应进行研究。结果表明,吴江市的耕地基底向建设用地基底转化,生态系统结构的多样性和均匀度降低,景观整体形状趋于规则;生态系统功能退化,耕地的减少以及建设用地面积的增加是导致总价值减少的主导力量,而水域生态服务价值的增加是阻止其显著减少的原因;水源涵养和废物处理功能贡献度最大,超过总价值的50%;汾湖镇所占生态服务价值比重最高,分别为24.2%、25.21%2、5.13%,桃源镇所占比重最低。     

基于AnnAGNPS模型的三峡库区秭归县生态服务价值

利用三峡库区秭归县统计和调查资料,并基于AnnAGNPS模型获取秭归县1985、1990、2000、2007年径流、土壤侵蚀和养分流失等数据,客观计量秭归县年际生态服务物质量,进而估算各年际生态服务价值量.结果表明,1985~2007年,秭归县生态服务物质量均发生了变化.2000年径流、泥沙、总氮、总磷和有机碳的年输出量最高,分别为473mm、68.6t/km2、133kg/km2、33kg/km2和684kg/km2,而2007年上述指标最低,分别为419mm、40.6t/km2、112kg/km2、20kg/km2和445 kg/km2,分别下降了12.8%、68.9%、18.7%、65.4%和53.5%;1985~2007年秭归县生态服务价值也发生了变化,2000年最低,为45.1亿元,2007年最高,为54.2亿元,增加了20.1%.利用调查统计和模型输出的方法进行生态服务价值量的计量较为客观准确,避免了一些计算上的不确定性,但该方法所需数据量庞大,可能会限定其他地区的应用.     

河网城市不透水面的河流生态系统响应:方法论框架

河网城市不透水面快速扩展,已成为影响河流生态系统健康的主要因素,理解掌握区域不透水面与河流生态系统之间的压力响应关系十分必要。以国外研究为重点,从不透水面的识别技术方法、 流域不透水面与河流生态系统状况之间的压力响应关系、 不透水面在流域土地利用规划调控和河流管理应用等三个方面,回顾了不透水面研究的主要进展,特别对不透水面影响河流生态系统的阈值效应进行了较细致梳理。从研究区域、 研究视角、 研究方法、 决策应用等四个方面,讨论了当前研究可能存在的问题。结合河网地区较为特殊的水文地貌特点,提出了河网城市开展相关研究的主要任务,认为必须解决的若干关键技术方法问题包括:不透水面实地调查方法及与有效不透水面转换、 汇水单元及其多尺度体系、 压力响应体系构建,以及数据分析技术方法等。最后以上海地区为案例,分析了河岸带尺度上的不透水面与河流生态系统之间的压力响应关系。这一研究体系框架试图为相关实证研究提供可实际操作的方法论参考。     

森林生态系统恢复力评价——以江西省莲花县为例

生态系统恢复力是森林资源可持续发展的中心目标之一。在明确生态系统恢复力定义和尺度的基础上,分析了森林生态系统恢复力的影响因素,从生境条件和生态存储两方面遴选出26个指标,建立了森林生态系统恢复力评价指标体系,并以江西省莲花县为案例区,采用组合赋权法确定了指标权重,通过空间叠加计算了莲花县森林生态系统恢复力。结果表明:森林生态系统恢复力主要受内部存储的影响,其权重达到0.554。莲花县森林生态系统恢复力在0.103到0.464之间,平均值为0.268,恢复力达到或超过平均水平的森林面积为37 907 hm²,占森林总面积的49.2%,整体处于较低水平;分级结果表明仅48.16%的森林达到高或较高恢复力水平;在空间分布上,莲花县森林生态系统恢复力为南高北低,南部和中部的森林大多处于高或较高恢复力水平,北部地区大部分森林处于中等、较低或低恢复力水平。此外,恢复力高的森林沿乡镇边界线分布的特点非常明显。该研究结果可为森林资源管理提供重要科学依据。