瑞典驼鹿(Alces alces)萎缩综合症:背景及当前的假说

20世纪80年代,在瑞典人们经常发现驼鹿死亡或身体状况差的情况.递交给瑞典国立兽医研究所(SVA)进行尸体常规检查的驼鹿数目增加了10倍之多.艾尔夫斯堡(Alvsborg)的狩猎者们对此尤为关注.随后,人们对驼鹿这一复杂的萎缩综合症进行了相关描述并从1991年开始收集有关患病驼鹿的报道.迄今为止,仍未找到该综合症确定的潜在病因,但人们提出了一些可能的假说以解释此综合症.这些假说基本上可以分为两类:食物相关假说和宿主-寄生虫相关假说.食物相关假说认为萎缩综合症有如下根本原因:酸化/撒石灰、采食动物密度/食物产量或污染.上述假说很少经严格实验检验,多半实验仅为一些观察结果支持,之所以这些假说与人们的预计相吻合,是因为这些假说是事后试图解释这些观察到的现象而提出的.     

人为因素对社会-生态系统脆弱性和恢复力影响的地理差异

横跨北极的地区,可更新资源和不可更新资源、人口密度、资产投资、住宅与交通基础设施的分布存在着很大差异,这些差异被公认为是研究当前和未来社会-生态系统变化的热点.由于当前政治和经济的稳定,芬诺斯堪的亚地区北部社会-生态系统呈现出相对良好的形势,而俄罗斯北部从苏联解体开始便一直经历着急速且消极的变化,这些变化反映了俄罗斯普遍存在的危机状态.北美洲虽然处在一个相对稳定有序的制度下,采取了一些措施用于防止和减轻与工业有关的环境退化,但大多即将出台的新发展计划仍将会显著扩大社会-生态系统受到潜在影响的空间范围.制度或管理条款与生态系统服务功能对环境变化的缓冲能力紧密相关.无论气候是否变暖,某些地理区域对外来破坏作用表现得特别脆弱,这有可能威胁到这些区域在将来提供产品和服务的能力.尽管某些地区的气候变化有可能会使这种形势恶化,但从长远来看,气候变化也有可能会使其恢复力得到加强.     

The financial additionality and viability of CDM projects allowing for uncertainty

Financial additionality and viability for Clean Development Mechanism (CDM) projects is commonly demonstrated through deterministic internal rate of return (IRR) benchmark analysis, supplemented with a sensitivity analysis. This method is vulnerable to assumptions on cash flows (including that from carbon credits) and is unable to differentiate grades of separation from the benchmark. This paper examines the financial additionality test and viability in the presence of cash flow uncertainty, where IRR becomes a random variable. A case example project involving wind power is exampled. It is seen that the boundaries between acceptance and rejection as a CDM project based on financial additionality and viability tests become blurred, leading to possible alternative conclusions. Comment is given on false positives and false negatives, in terms of acceptance and rejection of projects.     

Temporal change estimation of mercury concentrations in northern pike (Esox lucius L.) in Swedish lakes

Adequate temporal trend analysis of mercury (Hg) in freshwater ecosystems is critical to evaluate if actions from the human society have affected Hg concentrations ([Hg]) in fresh water biota. This study examined temporal change in [Hg] in Northern pike (Esox lucius L.) in Swedish freshwater lakes between 1994 and 2006. To achieve this were lake-specific, multiple-linear-regression models used to estimate pike [Hg], including indicator variables representing time and fish weight and their interactions. This approach permitted estimation of the direction and magnitude of temporal changes in 25 lakes selected from the Swedish national database on Hg in freshwater biota. A significant increase was found in 36% of the studied lakes with an average increase in pike [Hg] of 3.7 ± 6.7% per year that was found to be positively correlated with total organic carbon. For lakes with a significant temporal change the dataset was based on a mean of 30 fish, while for lakes with no temporal change it was based on a mean of 13 fish.     

Measurement, Collaborative Learning and Research for Sustainable Use of Ecosystem Services: Landscape Concepts and Europe as Laboratory

Policies at multiple levels pronounce the need to encompass both social and ecological systems in governance and management of natural capital in terms of resources and ecosystems. One approach to knowledge production and learning about landscapes as social–ecological systems is to compare multiple case studies consisting of large spaces and places. We first review the landscape concepts’ biophysical, anthropogenic, and intangible dimensions. Second, we exemplify how the different landscape concepts can be used to derive measurable variables for different sustainability indicators. Third, we review gradients in the three dimensions of the term landscape on the European continent, and propose to use them for the stratification of multiple case studies of social–ecological systems. We stress the benefits of the landscape concepts to measure sustainability, and how this can improve collaborative learning about development toward sustainability in social–ecological systems. Finally, analyses of multiple landscapes improve the understanding of context for governance and management.     

Body mass and parental decisions in the Antarctic petrel Thalassoica antarctica : how long should the parents guard the chick?

In Procellariiformes, the parents guard the chick after it has attained homeothermy. This strategy may reduce the probability that a small chick is taken by predators, but is costly as only one parent can forage at a time. The decision to leave the chick may therefore be a compromise between the chick's vulnerability to predators, the body condition of the parent on the nest and whether the foraging parent returns in time. We studied how the number of days that parents guarded the chick was related to the body mass of the parent at the nest and the time the foraging parent spent at sea in the Antarctic petrel Thalassoica antarctica. We also examined how the body mass of the parent on the nest and the duration of the foraging trips influenced the chicks' body condition at the end of the guarding period. When the foraging parent did not return to the nest in time to relieve its mate, the number of days the parent on the nest kept guarding the chick was positively related to its body mass on arrival in the colony. The number of days the foraging parent spent at sea was positively related to the body mass of its mate, but those that returned in time had a shorter stay at sea relative to their mate's body mass than those that did not return before their mate had left. Apparently, both the body mass of the parent at the nest and the ability of the foraging parent to adjust its stay at sea to the mate's body mass is important for the number of days the parents guard the chick and also the chick's body condition at this point. The inability to return to the nest before the mate has left may be the result of needing a minimum amount of time at sea to find food, or because some parents having low foraging success and therefore prolong their stay at sea. Received: 10 October 1997 / Accepted after revision: 14 March 1998     

Perfluorinated and chlorinated pollutants as predictors of demographic parameters in an endangered seabird

Despite global occurrence of several perfluorinated compounds (PFCs) the potential ecological effects of such substances on natural populations are not known. In endangered lesser black-backed gulls (Larus fuscus fuscus) on the Norwegian Coast, the blood concentrations of PFCs were as high as legacy organochlorines (OCs), and here we examined whether PFCs show associations similar to those of OCs to factors potentially affecting population growth, by evaluating relationships between contaminant concentrations and demographic parameters (reproductive performance and the probability of adults returning between breeding seasons). PFCs were not adversely associated with demographic parameters, while the most persistent OCs; notably PCB and p,p′-DDE, were adversely associated with early chick survival, and adult return rate. This study thus suggests that when the concentrations of PFCs and OCs are of similar magnitude in a gull population, OCs are more likely to cause adverse ecological effects.     

Social and Cultural Sustainability: Criteria, Indicators, Verifier Variables for Measurement and Maps for Visualization to Support Planning

Policies on economic use of natural resources require considerations to social and cultural values. In order to make those concrete in a planning context, this paper aims to interpret social and cultural criteria, identify indicators, match these with verifier variables and visualize them on maps. Indicators were selected from a review of scholarly work and natural resource policies, and then matched with verifier variables available for Sweden’s 290 municipalities. Maps of the spatial distribution of four social and four cultural verifier variables were then produced. Consideration of social and cultural values in the studied natural resource use sectors was limited. The spatial distribution of the verifier variables exhibited a general divide between northwest and south Sweden, and regional rural and urban areas. We conclude that it is possible to identify indicators and match them with verifier variables to support inclusion of social and cultural values in planning.     

Reconnecting to the Biosphere

Humanity has emerged as a major force in the operation of the biosphere, with a significant imprint on the Earth System, challenging social-ecological resilience. This new situation calls for a fundamental shift in perspectives, world views, and institutions. Human development and progress must be reconnected to the capacity of the biosphere and essential ecosystem services to be sustained. Governance challenges include a highly interconnected and faster world, cascading social-ecological interactions and planetary boundaries that create vulnerabilities but also opportunities for social-ecological change and transformation. Tipping points and thresholds highlight the importance of understanding and managing resilience. New modes of flexible governance are emerging. A central challenge is to reconnect these efforts to the changing preconditions for societal development as active stewards of the Earth System. We suggest that the Millennium Development Goals need to be reframed in such a planetary stewardship context combined with a call for a new social contract on global sustainability. The ongoing mind shift in human relations with Earth and its boundaries provides exciting opportunities for societal development in collaboration with the biosphere--a global sustainability agenda for humanity.     

Agriculture as Provider of Both Food and Fuel

A database of global agricultural primary production has been constructed and used to estimate its energy content. The portion of crops available for food and biofuel after postharvest losses was evaluated. The basic conditions for agriculture and plant growth were studied, to ensure sustainable scenarios regarding use of residues. The available energy contents for the world and EU27 was found to be 7,200–9,300 and 430 TWh, respectively, to be compared with food requirements of 7,100 and 530 TWh. Clearly, very little, or nothing, remains for biofuel from agricultural primary crops. However, by using residues and bioorganic waste, it was found that biofuel production could theoretically replace one-fourth of the global consumption of fossil fuels for transport. The expansion potential for global agriculture is limited by availability of land, water, and energy. A future decrease in supply of fossil energy and ongoing land degradation will thus cause difficulties for increased biofuel production from agriculture.