A framework designation for the assessment of urban ecological risks

Urban ecological risks stemming from urbanization are increasing and limiting the capability of China to effectuate sustainable urban development. Therefore, addressing urban ecological risks is an urgent need. Numerous factors are involved in urban ecological risks, including air, water, and soil. Additionally, risk sources and risk receptors are complex and diverse. In this study, urban ecological risks are defined as adverse effects and possibility of impacts on urban ecosystem services resulting from urbanization. Urbanization is recognized as the risk source, and the urban ecosystem is considered the risk receptor. Based on this understanding, the components of urban ecological risks are defined, and the relationships between the components of urban ecological risks are illuminated by establishing an indicator system. Based on previous studies on urban ecological risks, an explicit framework for identification, assessment, and management of urban ecological risks is proposed. For purposes of identification, there are three types of risk sources: population growth, industrial development, and the expansion of built land. Stressors include the accumulation of contaminants, consumption of resources, and occupation of space. Assessment endpoints are divided into provisioning, regulating, cultural, and supporting services. In response to urban ecological risks having multiple stressors and multiple assessment endpoints, we assessed risks both with a single stressor/single endpoint and comprehensive ecological risks. In our framework, the physical or material assessment of ecosystem services is adopted as the core method for the analysis of urban ecological risk, because it is believed that the analysis of urban ecological risk should be based on the physical or material assessment of ecosystem services instead of the value assessment of ecosystem services. The results of the single value assessment of urban ecosystem services will cause the deviation from the purpose of urban ecosystem services assessment. The purpose of urban ecosystem services assessment is to maintain and/or improve the capability of urban ecosystems of providing physical or material services, and further to reduce or avoid the occurrence risks of unsustainable cities. Additionally, a multi-level characterization method was adopted for the results of urban ecological risk assessment. In this study, we established a platform to manage urban ecological risks based on landscape ecology and environmental internet of things technologies, and to effectuate online urban ecological risk identification, assessment, and management via this platform.     

A Meta-Analysis of the Effects of Ultraviolet B Radiation and Its Synergistic Interactions with pH, Contaminants, and Disease on Amphibian Survival

Abstract:  Human alterations to natural systems have resulted in a loss of biological diversity around the world. Amphibian population losses have been more severe than those of birds and mammals. Amphibian population declines are likely due to many factors including habitat loss, disease, contaminants, introduced species and ultraviolet-B (UVB) radiation. The effect of UVB, however, varies widely among species and can vary within populations of the same species or at different life-history stages. This variation has often led to opposing conclusions about how UVB affects amphibians. We used meta-analysis techniques to explore the overall effects of UVB radiation on survival in amphibians. We also used recently developed factorial meta-analytic techniques to quantify potential interactions between UVB radiation and other stressors on amphibians. Ultraviolet-B radiation reduced survival of amphibians by 1.9-fold compared with shielded controls. Larvae were more susceptible to damage from UVB radiation compared with embryos, and salamanders were more susceptible compared with frogs and toads. Furthermore, UVB radiation interacted synergistically with other environmental stressors and resulted in greater than additive effects on survival when 2 stressors were present. Our results suggest that UVB radiation is an important stressor in amphibians, particularly in light of potential synergisms between UVB and other stressors in amphibian habitats.     

Assessment and management of urbanization-induced ecological risks

The urban ecological risk incurred during the processes of urbanization has been constantly accumulating, creating a severe challenge for China to achieve sustainable urban development. At present, research on systematic evaluation of urban ecological risks is still inadequate, especially at an urban ecosystem level. In this special issue, we use Xiamen City as an example to identify the sources and receptors of urban ecological risks, to develop a methodology system of urban ecological risk assessment, and to propose a method for the management of urban ecological risks. This special issue contains 11 research articles resulting from a comprehensive research project funded by China’s National Natural Science Foundation. The innovations reported in this special issue include a framework of urban ecological risk assessment and a standardized procedure for carrying out urban ecological risk assessment using multiple stressors and endpoints.     

产业生态系统多尺度能值整合评价方法

能值分析方法为自然环境资源与人类社会、经济的统一评价提供了新的思路,但面对当今产业生态学发展的实践需求,在多尺度整合分析、动态模型构建等方面仍显薄弱,需要与经济学等其他学科相对成熟的分析方法与模型加以整合。文章以能值综合方法为核心介质,从成本分析与效果分析的整合、能值分析与区域经济分析的整合,以及能值分析表与投入-产出矩阵模型的整合三个方面进行了产业生态学的能值整合研究方法的具体构建,以促进能值理论方法与产业生态学研究需求的进一步耦合。     

Assessing landscape values: a proposal for a multidimensional conceptual model

To evaluate a specific form of resource management, for example, the maintenance of valuable cultural landscapes, the contributions of many different viewpoints must be considered. In this paper, a model for assessing and integrating the different aspects contributing to landscape evaluation is proposed. Some results of its use in landscape assessment in the Madrid region (central Spain) are discussed.The model takes into account five assessment dimensions which are considered to be independent—the ecological, productive, economic, social and cultural evaluative systems and it recognises and assumes conflicts and trade-offs between these components. The inclusion of the production system as an independent assessment dimension is original and is justified because it is the link that connects the ecological and economic systems. Since this dimension acts most directly on the ecosystem, the production system includes the attribute of ecological or strong (in the sense of [For the Common Good, Beacon Press, Boston, 1994]) sustainability.The evaluation method places special emphasis on defining a conceptual framework, and from this defines scenarios in comparison with which particular development models (landscape planning, resources management) can be evaluated. Seven scenarios, coming from a hypothetical, traditional sustainable scenario of resources management, are defined. One of these, the sound sustainable scenario, is defended as the only one viable in the long term, particularly in developing countries.This method was employed to evaluate the agricultural and natural landscape of the Madrid region municipalities. The multivariate approach adopted was based on the selection of indicator sets for each evaluative dimension. The structure of relationships among indicators was then analysed separately for each dimension and values assigned to the municipalities according to their position on the main axes of the multivariate analyses. Each municipality was assigned to one of the seven development scenarios by means of discriminant analysis. The approach’s greatest assets are its flexibility in the selection of the indicators and the efficacy in its monitoring and comparison of the different analysed cases once a rigorous conceptual framework was established.The paper discusses the conditions for the sustainability of the human activities and provides a method for evaluating and comparing scenarios of resources management.     

Multiple anthropogenic stressors and the structural properties of food webs

Coastal environments are among the most productive on the planet, providing a wide range of ecosystem services. Development and exploitation mean that they are faced with stresses from a number of anthropogenic sources. Such stresses are typically studied in isolation, but multiple stressors can combine in unexpected ways to alter the structure of ecological systems. Here, we experimentally explore the impacts of inorganic nutrients and organic matter on a range of food web properties. We find that these two stressors combine additively to produce significant increases in connectance and mean food chain length. Such increases are typically associated with enhanced robustness to secondary extinctions and productivity, respectively. Despite these apparent beneficial effects, we find a simplification of web structure in terms of taxon richness and diversity, and altered proportions of basal and top species. These effects are driven by a reduction in community assembly and lower consistency in a range of system properties as a result of the multiple stressors. Consequently, impacted food webs are likely to be more vulnerable to human- or climate-induced perturbations in the long-term.     

对美国格林威治湾底栖动物造成危害的潜在胁迫因子的诊断

格林威治湾是纳拉甘西特湾一处受到多种影响因子作用的城市化形成港湾。本研究鉴定了对于格林威治湾底栖动物的重要影响因素。首先利用现存数据与信息来验证水体受损情况。其次确定了影响来源,影响因素和具体影响的存在。继而探究了来源,影响因素和具体影响之间的关系。这使我们能够鉴定出最可能危害水体的影响因素。本研究评估了化学制品、营养物质和悬浮沉积物3类污染物。这种证据权重的方法表明格林威治湾主要受到富营养化相关的影响因素危害。格林威治湾的沉积物富含碳,低溶解氧浓度的情况十分常见,尤其在格林威治湾西部。底栖生物群落出现发育不良的情况,与在氧气不足情况下的预测结果吻合。尽管我们的分析表明环境中的污染物浓度可能导致有害结果的出现,我们并未在结果中检出毒性。这是由于沉积物中存在大量的有机物,这些有机物限制了污染物的生物可利用性。我们的分析还表明悬浮沉积物的影响对于湾区的大部分区域而言几乎不存在。本分析展示了诊断法步骤可以用于组织和评估影响格林威治湾生态健康的潜在影响因素。诊断法步骤对于管理受到多重因素影响的水体非常有用。
精选自Marguerite Pelletier, Kay Ho, Mark Cantwell, Monique Perron, Kenneth Rocha, Robert M. Burgess, Roxanne Johnson, Kenneth Perez, John Cardin, Michael A. Charpentier. Diagnosis of potential stressors adversely affecting benthic invertebrate communities in Greenwich Bay, Rhode Island, USA. Environmental Toxicology and Chemistry: Volume 36, Issue 2, pages 449–462, July 2017. DOI: 10.1002/etc.3562
详情请见http://onlinelibrary.wiley.com/wol1/doi/10.1002/etc.3562/full
     

Effects of chytrid fungus and a glyphosate-based herbicide on survival and growth of wood frogs (Lithobates sylvaticus)

Anthropogenic-derived stressors in the environment, such as contaminants, are increasingly considered important cofactors that may decrease the immune response of amphibians to pathogens. Few studies, however, have integrated amphibian disease and contaminants to test this multiple-stressor hypothesis for amphibian declines. We examined whether exposure to sublethal concentrations of a glyphosate-based herbicide and two strains of the pathogenic chytrid fungus, Batrachochrytrium dendrobatidis (Bd) could: (1) sublethally affect wood frogs (Lithobates sylvaticus) by altering the time to and size at metamorphosis, and (2) directly affect survivability of wood frogs after metamorphosis. Neither Bd strain nor herbicide exposure alone significantly altered growth or time to metamorphosis. The two Bd strains did not differ in their pathogenicity, and both caused mortality in post-metamorphic wood frogs. There was no evidence of an interaction between treatments, indicating a lack of herbicide-induced susceptibility to Bd. However, the trends in our data suggest that exposure of wood frogs to a high concentration of glyphosate-based herbicide may reduce Bd-caused mortality compared to animals exposed to Bd alone. These results exemplify the complexities inherent when populations are coping with multiple stressors. In this case, the perceived stressor, glyphosate-based herbicide, appeared to affect the pathogen more than the host's immune system, relieving the host from disease-caused effects. This suggests caution when invoking multiple stressors as a cause for increased disease susceptibility and indicates that the effects of multiple stressors on disease outcome depend on the interrelationships of stressors to both the pathogen and the host.     

A model-based approach to determine the long-term effects of multiple interacting stressors on coral reefs

The interaction between multiple stressors on Caribbean coral reefs, namely, fishing effort and hurricane impacts, is a key element in the future sustainability of reefs. We develop an analytic model of coral-algal interactions and explicitly consider grazing by herbivorous reef fish. Further, we consider changes in structural complexity, or rugosity, in addition to the direct impacts of hurricanes, which are implemented as stochastic jump processes. The model simulations consider various levels of fishing effort corresponding to' several hurricane frequencies and impact levels dependent on geographic location. We focus on relatively short time scales so we do not explicitly include changes in ocean temperature, chemistry, or sea level rise. The general features of our approach would, however, apply to these other stressors and to the management of other systems in the face of multiple stressors. It is determined that the appropriate management policy, either local reef restoration or fisheries management, greatly depends on hurricane frequency and impact level. For sufficiently low hurricane impact and macroalgal growth rate, our results indicate that regions with lower-frequency hurricanes require stricter fishing regulations, whereas management in regions with higher-frequency hurricanes might be less concerned with enhancing grazing and instead consider whether local-scale restorative activities to increase vertical structure are cost-effective.     

A landscape-scale framework to identify refugia from multiple stressors

From a conservation perspective, quantifying potential refugial capacity has been predominantly focused on climate refugia, which is critical for maintaining the persistence of species and ecosystems. However, protection from other stressors, such as human-induced changes in fire and hydrology, that cause habitat loss, degradation, and fragmentation is also necessary to ensure that conservation efforts focused on climate are not undermined by other threats. Thus, conceptual and methodological advances for quantifying potential refugia from multiple anthropogenic stressors are important to support conservation efforts. We devised a new conceptual approach, the domains of refugia, for assessing refugial capacity that identifies areas where exposure to multiple stressors is low. In our framework, patterns of environmental variability (e.g., increased frequency of warm summers), thresholds of resilience, and extent and intensity of stressors are used to identify areas of potential refugia from a suite of ongoing anthropogenic stressors (e.g., changes in fire regime). To demonstrate its utility, we applied the framework to a Southern California landscape. Sites with high refugial capacity (super-refugia sites) had on average 30% fewer extremely warm summers, 20% fewer fire events, 10% less exposure to altered river channels and riparian areas, and 50% fewer recreational trails than the surrounding landscape. Our results suggest that super-refugia sites (∼8200 km²) for some natural communities are underrepresented in the existing protected area network, a finding that can inform efforts to expand protected areas. Our case study highlights how considering exposure to multiple stressors can inform planning and practice to conserve biodiversity in a changing world.     

危险化学品泄漏入海区域风险评估方法研究

我国的危险化学品区域风险评估研究工作起步较晚,针对危险化学品泄漏入海的方法研究较少。现有区域风险评估方法中评估对象多为单一风险因素,存在着未全面考虑研究区域内其他风险源和敏感资源等综合影响的不足。在结合国内外研究进展现状的基础上,强化与相关技术方法的衔接,建立了综合考虑危险化学品危险性和区域风险承受力等因素的危险化学品泄漏入海区域风险评估方法工作,并选择天津市XX企业开展方法案例应用。本研究能够为科学合理划分危险化学品泄漏区域海洋环境风险等级提供技术支撑,为开展危险化学品泄漏入海风险防范和修复评估等工作提供决策依据。     

深圳市主要外来入侵植物调查及治理状况

通过对深圳市具有代表性的公共园林绿地中的外来入侵植物的调查,确定薇甘菊和五爪金龙为深圳市为害最为严重的外来入侵植物。对这两种植物的群落特征进行调查发现,这两种植物具有相似的生态适应性,可共同生长于同一生境中,为害深圳市多种本地植物,对低矮乔木、灌木和草本植物为害严重,对高大乔木的为害不明显。目前深圳市多采用物理、化学防治为主,结合简单生物防治的方法控制其为害,但效果不理想。目前还没有较为成熟的生物防治方法。     

Identification and assessment of environmental burdens of Chinese copper production from a life cycle perspective

The environmental burdens of Chinese copper production have been identified and quantified in the context of typical technologies, materials supplies and environmental emissions by a life cycle approach. Primary and secondary copper production using copper ores and scraps, respectively, were analyzed in detail. The flash and bath smelting approaches and the recycling of copper scraps were selected as representative copper production processes. A quantitative analysis was also conducted to assess the influence of material transport distance in copper production. Life cycle assessment （LCA） results showed that resources depletion and human health contribute significantly to environmental burdens in Chinese copper production. In addition, the secondary copper production has dramatically lower environmental burdens than the primary production. There is no obvious distinction in overall environmental burdens in primary copper production by flash or bath smelting approach. However, resources depletion is lower and the damage to human health is higher for flash smelting approach. Ecosystem quality damage is slight for both approaches. Environ- mental burdens from the mining stage contribute most in all life cycle stages in primary copper production. In secondary copper production, the electrolytic refining stage dominates. Based on the life cycle assessment results, some suggestions for improving environmental performance were proposed to meet the sustainable development of Chinese copper industry.     

Obstacles to Bottom‐Up Implementation of Marine Ecosystem Management

Abstract: Ecosystem management (EM) offers a means to address multiple threats to marine resources. Despite recognition of the importance of stakeholder involvement, most efforts to implement EM in marine systems are the product of top‐down regulatory control. We describe a rare, stakeholder‐driven attempt to implement EM from the bottom up in San Juan County, Washington (U.S.A.). A citizens advisory group led a 2‐year, highly participatory effort to develop an ecosystem‐based management plan, guided by a preexisting conservation‐planning framework. A key innovation was to incorporate social dimensions by designating both sociocultural and biodiversity targets in the planning process. Multiple obstacles hindered implementation of EM in this setting. Despite using a surrogate scheme, the information‐related transaction costs of planning were substantial: information deficits prevented assessment of some biodiversity targets and insufficient resources combined with information deficits prevented scientific assessment of the sociocultural targets. Substantial uncertainty, practical constraints to stakeholder involvement, and the existence of multiple, potentially conflicting, objectives increased negotiation‐related costs. Although information deficits and uncertainty, coupled with underinvestment in the transaction costs of planning, could reduce the long‐term effectiveness of the plan itself, the social capital and momentum developed through the planning process could yield unforeseeable future gains in protection of marine resources. The obstacles we identified here will require early and sustained attention in efforts to implement ecosystem management in other grassroots settings.     

Modeling and interpreting the accuracy assessment error matrix for a doubly classified map

This paper considers two maps having the same spatial extent and the same mapping categories but where each map is subject to classification error. An overlay of the maps yields a (dis)similarity matrix whose (i, j)-entry is the areal proportion placed into category i by the first map and into category j by the second map. A parametric model, called the latent truth model, is proposed which specifies the dissimilarity matrix in terms of the true (but unknown) proportions for the mapping categories as well as the unknown error rates for the two maps. The number of parameters in the model exceeds the degrees of freedom in the dissimilarity matrix. However, a method of regularization is applied to effectively reduce the dimension of the parameter space and to permit model fitting. From the fitted model, one obtains estimates for the true mapping proportions as well as estimated error matrices for each of the maps. Accuracy assessment characteristics for each map (such as user's accuracy, producer's accuracy, overall accuracy, and the kappa coefficient) can be computed from the estimated error matrices. Methods are illustrated with two landcover maps of Wicomico County, Maryland.     

Development and application of a comprehensive ecological risk assessment indicator system in Xiamen,China

Urban ecological risk is one of the important factors that may restrict the social and economic development. Therefore, it is of great significance to carry out a comprehensive assessment of ecological risks so that an ecological risk prevention and control plan can be scientifically formulated. In this paper, a comprehensive ecological risk assessment indicator system of Xiamen was established based on local ecological properties and socioeconomic status. This indicator system covers seven indicators including air pollution, soil pollution, water pollution, fresh water consumption, change in land use, occupation of key zones with ecological functions, and road network expansion. Based on this indicator system and in conjunction with the single factor assessment of ecological risks, this study constructed a model of comprehensive ecological risk assessment and forecasted the comprehensive ecological risk of Xiamen in 2020. The results showed that the comprehensive ecological risk level of Xiamen in 2020 is medium and the main stressors are the discharge of air and water pollutants. From the perspective of risk receptors, i.e. the ecosystem services, the risk posed to the ecosystem services associated to the maintenance of air quality and water purification is the highest. Therefore, this study proposed the recommendations on ecological risk prevention and regulation in Xiamen based on the comprehensive assessment of ecological risks, in the hope to provide scientific support for local ecological protection and sustainable development.     

Detecting pattern in biological stressor response relationships using model based cluster analysis

Environmental monitoring of aquatic systems is needed to estimate the quality of the systems, to evaluate standards and to study stressor–response relationships. Monitoring programs often focus on the collection of biological, chemical and physical measures of the system. An important concern is the effect of chemical and physical stressors on the biological community. Evaluation of relationships may be difficult as the extent of the relationship is not known. From a management perspective, interest is on what factors affect the biological community and where these factors have an influence. The focus of this paper is on the use of regression based cluster analysis as a tool for finding relationships between a single biological response and a suite of environmental stressors. The approach to cluster analysis uses a penalized regression classification likelihood and Markov Chain Model Composition Monte Carlo. This approach allows for simultaneous development of regression models and clustering of the regression models. The method is applied to the analysis of a data set describing stressors/response relationship in Ohio.     

Characterization of biological responses under different environmental conditions: A hierarchical modeling approach

A natural river system is organized as a nested hierarchy of interconnected habitats with specific environmental conditions to which the biological community has adapted. Due to this hierarchical structure, identifying the role of different stressors on the biological community is a formidable task. Efforts trying to link stressors to biological integrity have always been bound to the geographic scale of the selected study area, leading to scale-specific results. In this research, an attempt is made to lift this limitation and develop a hierarchical, scale-sensitive methodology that can identify the significant environmental stressors to the biological community at different scales. Sites with similar background environmental conditions are clustered using self-organizing maps (SOM). This is used to identify stressors which affect the biological community throughout the area of study - called environmental gradients or large-scale stressors. Subsequently, these clusters of similar observations (sampling sites) are progressively sub-divided using environmental variables with a significant but localized effect on the biological community - called small-scale stressors. A parent group of sites is split only when the resulting sub-groups have significantly different biological responses. At the end of this recursive sites decomposition procedure, the original set of observations is organized as a tree of environmentally homogeneous groups of observations characterized by unique biological responses to multiple stressors with different geographic extents. The developed hierarchical analysis methodology has been validated using a large-size dataset of environmental observations from the State of Ohio. Our results show that habitat degradation and increased nutrient loading are the large-scale stressors with a widespread impact in Ohio. Other stressors, such as heavy metals, pH or nitrate concentrations have significant albeit localized effects on biological integrity.     

How complex do models need to be to predict dispersal of threatened species through matrix habitats?

Persistence of species in fragmented landscapes depends on dispersal among suitable breeding sites, and dispersal is often influenced by the "matrix" habitats that lie between breeding sites. However, measuring effects of different matrix habitats on movement and incorporating those differences into spatially explicit models to predict dispersal is costly in terms of time and financial resources. Hence a key question for conservation managers is: Do more costly, complex movement models yield more accurate dispersal predictions? We compared the abilities of a range of movement models, from simple to complex, to predict the dispersal of an endangered butterfly, the Saint Francis' satyr (Neonympha mitchellii francisci). The value of more complex models differed depending on how value was assessed. Although the most complex model, based on detailed movement behaviors, best predicted observed dispersal rates, it was only slightly better than the simplest model, which was based solely on distance between sites. Consequently, a parsimony approach using information criteria favors the simplest model we examined. However, when we applied the models to a larger landscape that included proposed habitat restoration sites, in which the composition of the matrix was different than the matrix surrounding extant breeding sites, the simplest model failed to identify a potentially important dispersal barrier, open habitat that butterflies rarely enter, which may completely isolate some of the proposed restoration sites from other breeding sites. Finally, we found that, although the gain in predicting dispersal with increasing model complexity was small, so was the increase in financial cost. Furthermore, a greater fit continued to accrue with greater financial cost, and more complex models made substantially different predictions than simple models when applied to a novel landscape in which butterflies are to be reintroduced to bolster their populations. This suggests that more complex models might be justifiable on financial grounds. Our results caution against a pure parsimony approach to deciding how complex movement models need to be to accurately predict dispersal through the matrix, especially if the models are to be applied to novel or modified landscapes.