生态质量与生态系统服务功能

生态系统服务功能是自然生态过程对人类的贡献。文章阐述了生态系统服务功能的定义、内涵及其与生态质量和生态系统健康三者间密不可分的关系。迅猛的人口增长、社会变化和技术发展,已使承载人类社会的生命之舟－大自然受到严重破坏和巨大威胁,减少这些破坏和威胁是整个社会特别是生态学工作者面临的重大挑战。只有深入认识三者之间的关系及其重要性,才能自觉防止和减少带有自我毁灭性的经济和社会活动。     

生态质量与生态系统服务功能

生态系统服务功能是自然生态过程对人类的贡献。文章阐述了生态系统服务功能的定义、内涵及其与生态质量和生态系统键康三者间密不可分的关系。迅猛的人口增长、社会变化和技术发展,已使承载人类社会的生命之舟——大自然受到严重破坏和巨大威胁,减少这些破坏和威胁是整个社会特别是生态学工作者面临的重大挑战。只有深入认识三者之间的关系及其重要性,才能自觉防止和减少带有自我毁灭性的经济和社会活动。     

Looking to the Future of Ecosystem Services

Ecosystem services—the benefits that people obtain from ecosystems—are essential to human existence, but demands for services often surpass the capacity of ecosystems to provide them. Lack of ecological information often precludes informed decision making about ecosystem services. The Millennium Ecosystem Assessment (MA) was conceived in part to provide the necessary ecological information to decision makers. To this end, the MA set out to address the stated needs and concerns of decision makers and examine the ecological dynamics and uncertainties underlying these concerns. To improve our understanding of their information needs and concerns, we interviewed 59 decision makers from five continents. The respondents indicated that although most people generally agree about the ideal state of the planet—free of poverty and extreme inequality, replete with cultural and biological diversity—they often disagree about the best way to achieve these goals. Further, although nonspecialists are generally concerned about the environment and may have a good understanding of some of issues, they often have a more limited grasp of the ecological dynamics that drive the issues of concern. We identify some of the principal uncertainties about ecosystem dynamics and feedbacks that underlie the concerns of decision makers. Each of the papers in this special feature addresses these ecological feedbacks from the perspective of a specific discipline, suggesting ways in which knowledge of ecological dynamics can be incorporated into the MA’s assessment and scenario-building process.     

Ecosystem Services of Woody Crop Production Systems

Short-rotation woody crops are an integral component of regional and national energy portfolios, as well as providing essential ecosystem services such as biomass supplies, carbon sinks, clean water, and healthy soils. We review recent USDA Forest Service Research and Development efforts from the USDA Biomass Research Centers on the provisioning of these ecosystem services from woody crop production systems. For biomass, we highlight productivity and yield potential, pest susceptibility, and bioenergy siting applications. We describe carbon storage in aboveground woody biomass and studies assessing the provision of clean and plentiful water. Soil protection and wildlife habitat are also mentioned, in the context of converting lands from traditional row-crop agriculture to woody production systems.     

Restoration of Biodiversity and Ecosystem Services on Agricultural Land

Cultivation and cropping are major causes of destruction and degradation of natural ecosystems throughout the world. We face the challenge of maintaining provisioning services while conserving or enhancing other ecosystem services and biodiversity in agricultural landscapes. There is a range of possibilities within two types of intervention, namely “land sharing” and “land separation”; the former advocates the enhancement of the farmed environment, but the latter a separation between land designated for farming versus conservation. Land sharing may involve biodiversity-based agricultural practices, learning from traditional farming, changing from conventional to organic agriculture and from “simple” crops and pastures to agro-forestry systems, and restoring or creating specific elements to benefit wildlife and particular services without decreasing agricultural production. Land separation in the farmland context involves restoring or creating non-farmland habitat at the expense of field-level agricultural production—for example, woodland on arable land. Restoration by land sharing has the potential to enhance agricultural production, other ecosystem services and biodiversity at both the field and landscape scale; however, restoration by land separation would provide these benefits only at the landscape scale. Although recent debate has contrasted these approaches, we suggest they should be used in combination to maximize benefits. Furthermore, we suggest “woodland islets”, an intermediate approach between land abandonment and farmland afforestation, for ecological restoration in extensive agricultural landscapes. This approach allows reconciliation of farmland production, conservation of values linked to cultural landscapes, enhancement of biodiversity, and provision of a range of ecosystem services. Beyond academic research, restoration projects within agricultural landscapes are essential if we want to halt environmental degradation and biodiversity loss.     

How Social and Nonsocial Context Affects Stay/Leave Decision-Making: The Influence of Actual and Expected Rewards

This study investigated whether deciding to either stay with or leave a social relationship partner, based on a sequence of collaborative social interactions, is impacted by (1) observed and (2) anticipated gains and losses associated with the collaboration; and, importantly, (3) whether these effects differ between social and nonsocial contexts. In the social context, participants played an iterated collaborative economic game in which they were dependent on the successes and failures of a game partner in order to increase their monetary payoff, and in which they were free to stop collaborating with this partner whenever they chose. In Study 1, we manipulated the actual success rate of partners, and demonstrated that participants decided to stay longer with ''better'' partners. In Study 2, we induced prior expectations about specific partners, while keeping the objective performance of all partners equal, and found that participants decided to stay longer with partners whom they expected to be ''better'' than others, irrespective of actual performance. Importantly, both Study 1 and 2 included a nonsocial control condition that was probabilistically identical to the social conditions. All findings were replicated in nonsocial context, but results demonstrated that the effect of prior beliefs on stay/leave decision-making was much less pronounced in a social than a nonsocial context.     

Ship-borne Nonindigenous Species Diminish Great Lakes Ecosystem Services

We used structured expert judgment and economic analysis to quantify annual impacts on ecosystem services in the Great Lakes, North America of nonindigenous aquatic species introduced by ocean-going ships. For the US waters, median damages aggregated across multiple ecosystem services were Open image in new window 138 million per year, and there is a 5% chance that for sportfishing alone losses exceeded Open image in new window 800 million annually. Plausible scenarios of future damages in the US waters alone were similar in magnitude to the binational benefits of ocean-going shipping in the Great Lakes, suggesting more serious consideration is warranted for policy options to reduce the risk of future invasions via the St. Lawrence Seaway.     

Global Drivers and Tradeoffs of Three Urban Vegetation Ecosystem Services

Our world is increasingly urbanizing which is highlighting that sustainable cities are essential for maintaining human well-being. This research is one of the first attempts to globally synthesize the effects of urbanization on ecosystem services and how these relate to governance, social development and climate. Three urban vegetation ecosystem services (carbon storage, recreation potential and habitat potential) were quantified for a selection of a hundred cities. Estimates of ecosystem services were obtained from the analysis of satellite imagery and the use of well-known carbon and structural habitat models. We found relationships between ecosystem services, social development, climate and governance, however these varied according to the service studied. Recreation potential was positively related to democracy and negatively related to population. Carbon storage was weakly related to temperature and democracy, while habitat potential was negatively related to democracy. We found that cities under 1 million inhabitants tended to have higher levels of recreation potential than larger cities and that democratic countries have higher recreation potential, especially if located in a continental climate. Carbon storage was higher in full democracies, especially in a continental climate, while habitat potential tended to be higher in authoritarian and hybrid regimes. Similar to other regional or city studies we found that the combination of environment conditions, socioeconomics, demographics and politics determines the provision of ecosystem services. Results from this study showed the existence of environmental injustice in the developing world.