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1.
Gorenflo LJ  Brandon K 《Ambio》2005,34(3):199-204
Agricultural development is a leading cause of habitat destruction that increasingly threatens global biodiversity. To help understand the likelihood and implications of agricultural expansion in areas of high conservation importance, this article examines agricultural suitability in forested portions of biodiversity hotspots and tropical wilderness areas, regions with especially rich concentrations of species found nowhere else. The study employs geographic information system technology to examine suitability for six crop categories in selected conservation localities worldwide: those portions of regions containing high biodiversity, protected areas (e.g. national parks) within these regions, and 10-km bands around the protected areas that are dominated by forest. Analyses reveal low suitability for most crop categories under both commercial and subsistence scenarios, with a few exceptions. In most cases, adequate planning can enable the coexistence of agriculture and biodiversity without compromising either.  相似文献   

2.
Novel urban ecosystems, biodiversity, and conservation   总被引:2,自引:0,他引:2  
With increasing urbanization the importance of cities for biodiversity conservation grows. This paper reviews the ways in which biodiversity is affected by urbanization and discusses the consequences of different conservation approaches. Cities can be richer in plant species, including in native species, than rural areas. Alien species can lead to both homogenization and differentiation among urban regions. Urban habitats can harbor self-sustaining populations of rare and endangered native species, but cannot replace the complete functionality of (semi-)natural remnants. While many conservation approaches tend to focus on such relict habitats and native species in urban settings, this paper argues for a paradigm shift towards considering the whole range of urban ecosystems. Although conservation attitudes may be challenged by the novelty of some urban ecosystems, which are often linked to high numbers of nonnative species, it is promising to consider their associated ecosystem services, social benefits, and possible contribution to biodiversity conservation.  相似文献   

3.
Since sewage discharges can significantly contribute to the contaminant loadings in coastal areas, it is important to identify sources, pathways and environmental sinks. Sterol and fatty alcohol biomarkers were quantified in source materials, suspended sediments and settling matter from the Ria Formosa Lagoon. Simple ratios between key biomarkers including 5beta-coprostanol, cholesterol and epi-coprostanol were able to identify the sewage sources and effected deposition sites. Multivariate methods (PCA) were used to identify co-varying sites. PLS analysis using the sewage discharge as the signature indicated approximately 25% of the variance in the sites could be predicted by the sewage signature. A new source of sewage derived organic matter was found with a high sewage predictable signature. The suspended sediments had relatively low sewage signatures as the material was diluted with other organic matter from in situ production. From a management viewpoint, PLS provides a useful tool in identifying the pathways and accumulation sites for such contaminants.  相似文献   

4.
We analyze detailed atmospheric gas/aerosol composition data acquired during the 2008 NASA ARCTAS (Arctic Research of the Composition of the Troposphere from Aircraft and Satellites) airborne campaign performed at high northern latitudes in spring (ARCTAS-A) and summer (ARCTAS-B) and in California in summer (ARCTAS-CARB). Biomass burning influences were widespread throughout the ARCTAS campaign. MODIS data from 2000 to 2009 indicated that 2008 had the second largest fire counts over Siberia and a more normal Canadian boreal forest fire season. Near surface arctic air in spring contained strong anthropogenic signatures indicated by high sulfate. In both spring and summer most of the pollution plumes transported to the Arctic region were from Europe and Asia and were present in the mid to upper troposphere and contained a mix of forest fire and urban influences. The gas/aerosol composition of the high latitude troposphere was strongly perturbed at all altitudes in both spring and summer. The reactive nitrogen budget was balanced with PAN as the dominant component. Mean ozone concentrations in the high latitude troposphere were only minimally perturbed (<5 ppb), although many individual pollution plumes sampled in the mid to upper troposphere, and mixed with urban influences, contained elevated ozone (ΔO3/ΔCO = 0.11 ± 0.09 v/v). Emission and optical characteristics of boreal and California wild fires were quantified and found to be broadly comparable. Greenhouse gas emission estimates derived from ARCTAS-CARB data for the South Coast Air Basin of California show good agreement with state inventories for CO2 and N2O but indicate substantially larger emissions of CH4. Simulations by multiple models of transport and chemistry were found to be broadly consistent with observations with a tendency towards under prediction at high latitudes.  相似文献   

5.
Background, aim, and scope  Large-scale deforestation is occurring in subarctic North America following clearing by salvage logging or insect attack. Numerous shrubs, herbs, and deciduous tree species tend to dominate areas on which stands of white spruce have grown. In the absence of economically advantageous mechanical methods, several herbicides have value in efforts to reforest by planting white spruce. Glyphosate, imazapyr, triclopyr, and hexazinone are all capable of selectively removing many competing species, but there is concern about whether they would degrade naturally or persist owing to the frigid climate. Materials and methods  We established test plots with all four herbicides in upland and river bottom sites at 65°N and 58°N latitudes. The northern site has extremely cold winters, with soils that freeze to a depth of 1–2 m, and precipitation of 275 mm/year. The southern site has heavy rain and snowfall, amounting to 2,250 mm/year evenly distributed. Soil seldom freezes deeply. On each test plot, one of the four herbicides was applied at twice the normal operational use rate to facilitate detection. They were applied at the normal timing, with hexazinone, imazapyr, and triclopyr applied in June and glyphosate applied in fall. Soils were sampled immediately after treatment and those samples used as references for dissipation data gathered over the next 11–14 months from soil 0- to 15- and 15- to 45-cm depths. Results  Dissipation rates did not follow first-order rates because freezing conditions slowed most microbial activity. All products dissipated to close to or below detection limits within the time of the study. Dissipation from vegetation was substantially more rapid and depended on the nature of the plants treated as well as the product used. While soil residues dissipated more slowly than in temperate regions, they did display consistent dissipation patterns during above-freezing conditions and also the influence of microbial activity. Mobility was very limited with all products but hexazinone. Discussion  These products dissipate during summer in high latitudes much as they would in temperate climates. Winter changes are small, but are not unlike some changes reported elsewhere under freezing conditions. Unlike many other studies, soil water did not influence dissipation heavily, but the high latitude and semi-arid climate also did not create severely droughty soils. Residues in plants were much higher than those in soils, but denatured the vegetation quickly, leading to unsuitability for forage in any case. Conclusions  Low toxicity of these products and their metabolites combined with consistent dissipation and low mobility suggest that toxic hazard of their use at high latitudes need not be a matter of serious concern to humans, terrestrial wildlife, or aquatic systems. They are safe for use in management and rehabilitation of boreal forests when used properly. Recommendations and perspectives  Dissipation at rates approaching those in warmer climates offer a hypothesis that microflora native to high latitudes may be adapted to destruction of such molecules at lower temperatures than may be indicated by experiments with microflora adapted to warmer climates. Residues pose no observable risk to wildlife or humans in the area of use when products are applied properly. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available for authorized users.  相似文献   

6.
Results from an ozone monitoring programme during the summers of 1975 and 1976 in the lower Telemark area (ca. 59°N) in Norway shows that elevated ozone concentrations (up to 120 ppb) occurred, mainly during prevailing high pressure situations. Wind trajectory analyses indicate that the elevated ozone concentrations in part seem to be generated from locally emitted precursors, and in part are associated with long range transport in north-western Europe.  相似文献   

7.
Curran SR  Cruz MC 《Ambio》2002,31(4):373-376
Our synthesis focuses on how markets influence the population and environment relationship within coastal ecosystems by considering the differential valuing of environmental resources and ecosystem services through 3 perspectives: livelihood, globalization, and public goods and externalities. These are not new perspectives when considering how markets shape demographic and environmental outcomes. However, we suggest that the insight offered by viewing coastal and marine health through these combined lenses brings into focus with renewed urgency the perils facing these vital ecosystems.  相似文献   

8.
The natural range of variation of ecosystems provides reference conditions for sustainable management and biodiversity conservation. We review how the understanding of natural reference conditions of boreal forests in northern Europe has changed from earlier perceptions of even-aged dynamics driven by stand-replacing disturbances towards current understanding highlighting the role of non-stand-replacing disturbances and the resultant complex forest dynamics and structures. We show how earlier views and conceptual models of forest disturbance dynamics, including the influential ASIO model, provide estimates of reference conditions that are outside the natural range of variation. Based on a research synthesis, we present a revised forest reference model incorporating the observed complexity of ecosystem dynamics and the prevalence of old forests. Finally, we outline a management model and demonstrate its use in forest ecosystem management and show how regional conservation area needs can be estimated. We conclude that attaining favourable conservation status in northern Europe’s boreal forests requires increasing emphasis on ecosystem management and conservation for old forest characteristics.Electronic supplementary materialThe online version of this article (10.1007/s13280-020-01444-3) contains supplementary material, which is available to authorized users.  相似文献   

9.
10.
Galaz V 《Ambio》2005,34(7):567-572
Dealing with uncertainty and complexity in social-ecological systems is profoundly dependent on the ability of natural resource users to learn and adapt from ecological surprises and crises. This paper analyzes why and how learning processes are affected by strategic behavior among natural resource users and how social conflict is affected by social and ecological uncertainty. The claim is that social conflict among natural resource users seriously inhibits the possibilities of learning and adaptation in social-ecological systems. This is done combining insights from political science, experimental economics, and social-psychology and an analytical case study elaborating social conflict and institutional change in Swedish water management institutions. This paper also discusses the crucial role the institutional context plays in defining the outcome of learning processes in Swedish water management institutions and hence highlights previously poorly elaborated political aspects of learning processes and institutional change in social-ecological systems.  相似文献   

11.
Chris Sandbrook 《Ambio》2015,44(4):636-647
Unmanned aerial vehicles, or ‘drones’, appear to offer a flexible, accurate and affordable solution to some of the technical challenges of nature conservation monitoring and law enforcement. However, little attention has been given to their possible social impacts. In this paper, I review the possible social impacts of using drones for conservation, including on safety, privacy, psychological wellbeing, data security and the wider understanding of conservation problems. I argue that negative social impacts are probable under some circumstances and should be of concern for conservation for two reasons: (1) because conservation should follow good ethical practice; and (2) because negative social impacts could undermine conservation effectiveness in the long term. The paper concludes with a call for empirical research to establish whether the identified social risks of drones occur in reality and how they could be mitigated, and for self-regulation of drone use by the conservation sector to ensure good ethical practice and minimise the risk of unintended consequences.  相似文献   

12.
Guo Q 《Ambio》2003,32(6):428-430
Both frequency and intensity of disturbances in many ecosystems have been greatly enhanced by increasing human activities. As a consequence, the short-lived plant species including many exotics might have been dramatically increased in terms of both richness and abundance on our planet, while many long-lived species might have been lost. Such conclusions can be drawn from broadly observed successional cycles in both theoretical and empirical studies. This article discusses 2 major issues that have been largely overlooked in current ecosystem management policies and conservation efforts: i) life history constraints; and ii) future global warming trends. It also addresses the importance of these 2 factors in balancing disturbance frequency and intensity for optimal biodiversity maintenance and ecosystem management.  相似文献   

13.
At a global level, the relationship between biodiversity importance and capacity to manage it is often assumed to be negative, without much differentiation among the more than 200 countries and territories of the world. We examine this relationship using a database including terrestrial biodiversity, wealth and governance indicators for most countries. From these, principal components analysis was used to construct aggregated indicators at global and regional scales. Wealth, governance, and scientific capacity represent different skills and abilities in relation to biodiversity importance. Our results show that the relationship between biodiversity and the different factors is not simple: in most regions wealth and capacity varies positively with biodiversity, while governance vary negatively with biodiversity. However, these trends, to a certain extent, are concentrated in certain groups of nations and outlier countries. We discuss our results in the context of collaboration and joint efforts among biodiversity-rich countries and foreign agencies.

Electronic supplementary material

The online version of this article (doi:10.1007/s13280-014-0581-0) contains supplementary material, which is available to authorized users.  相似文献   

14.
Bruckmeier K  Neuman E 《Ambio》2005,34(2):91-100
Most of the Swedish coastal fisheries are not sustainable from either a social, economic or ecological point of view. We propose the introduction of local fisheries management (LFM) as a tool for restructuring the present large-scale management system in order to achieve sustainability. To implement LFM two questions need to be answered: How to distribute the resource fish among different resource user groups? How to restructure present fisheries management to meet the criteria of sustainability? Starting from these questions we describe possible forms of LFM for Swedish coastal fishery supported by recent research. The biological and social preconditions for restructuring fisheries management are derived from an analysis of the ecological and managerial situation in Swedish fishery. Three types of LFM--owner based, user based, and community based management--are analyzed with regard to the tasks to be carried outin LFM, the roles of management groups, and the definition and optimal size of management areas.  相似文献   

15.
16.
The arctic tundra and boreal forest were once considered the last frontiers on earth because of their vast expanses remote from agricultural land-use change and industrial development. These regions are now, however, experiencing environmental and social changes that are as rapid as those occurring anywhere on earth. This paper summarizes the role of northern regions in the global system and provides a blueprint for assessing the factors that govern their sensitivity to social and environmental change.  相似文献   

17.
Baltic Sea populations of the northern pike (Esox lucius) have declined since the 1990s, and they face additional challenges due to ongoing climate change. Pike in the Baltic Sea spawn either in coastal bays or in freshwater streams and wetlands. Pike recruited in freshwater have been found to make up about 50 % of coastal pike stocks and to show natal homing, thus limiting gene flow among closely located spawning sites. Due to natal homing, sub-populations appear to be locally adapted to their freshwater recruitment environments. Management actions should therefore not involve mixing of individuals originating from different sub-populations. We offer two suggestions complying with this advice: (i) productivity of extant freshwater spawning populations can be boosted by modifying wetlands such that they promote spawning and recruitment; and (ii) new sub-populations that spawn in brackish water can potentially be created by transferring fry and imprinting them on seemingly suitable spawning environments.  相似文献   

18.
19.
Woodwell GM 《Ambio》2002,31(5):432-436
The objectives of conservation have been focused ever more intensively for two decades on the preservation of "biodiversity." Emphasis has been on the losses of species through extinction. The cure has been the establishment of parks and reserves to protect "hot spots," especially in the tropics, where the diversity of species is high. The efforts in preservation have often extended to the development of connecting links among reserves to allow movements among them. The approach has been codified in law in the form of the Endangered Species Act in the United States and the Biodiversity Treaty, both of which address the issue species by species and each of which has obvious weaknesses. Such efforts may be appropriate but they are totally inadequate as the sum of activities in conservation in a world of 6 billion people with exploding technologies for exploiting virtually all of the earth for immediate human benefit. The biosphere is decaying rapidly as a habitat for all life, including people, not because of the extinction of species, but because of the progressive impoverishment of natural communities through human-induced chronic disruption that is now global and ubiquitous. The improverishment leads to progressive environmental dysfunction that is cumulative, but only in its later stages leads to extinction of species. Long before extinction becomes important, genetically distinct, local ecotypes are lost and the natural communities in which they were developed become improverished and dysfunctional. The most conspicuous disruption is that of climate, a global change in the environment of every ecosystem. The most elaborate and carefully interlinked array of natural reserves will succumb as climate is moved out from under them... and biodiversity will suffer the very extinctions the parks were established to avoid. But long before that, the human environment will suffer conspicuous and progressive impoverishment. The objective of conservation is the preservation of the integrity of function of landscapes (and waterbodies). Emphasis falls on forests in the normally naturally forested parts of the earth because forests are so large in area globally and have such a large influence on virtually every aspect of environment. Functional integrity requires structural integrity over 85% or more of the naturally forested zone in most areas. It also requires objective measurement and definition by the scientific community. Suddenly, conservation has become, not the preservation of biodiversity, honorable as that may be, but the preservation of the functional integrity of the human environment. That purpose is the central purpose that we assign to the governments that we establish in democracies to define and defend the public interest. It is past time for the scientific and conservation communities to recognize the urgency of this transition, join in defining competent new objectives for conservation, and to convey to the public the urgency of the need for governmental responsibility in protecting the public interest in a habitable biosphere.  相似文献   

20.
It has been increasingly recognized that taxonomic diversity indices have a number of desirable properties as an indicator for assessing ecological quality status, in particular their less sensitivity to natural habitat type and sampling effort but more to environmental stress and anthropogenic impact, and a statistical framework for the assessment of the significance of departure from expectation. Taxonomic patterns of macroinvertebrate fauna for assessing ecological quality status were studied based on six datasets collected from intertidal zones of the Yellow Sea, near Qingdao, northern China, during the period of 1989?C1998. The invertebrate communities were sampled yearly at five stations with different bottom types during summer season (June). A total of 141 macroinvertebrate taxa were identified belonging 119 genera, 81 families, 34 orders, 19 classes, and 10 phyla. Multivariate analyses demonstrated that the taxonomic patterns of invertebrate fauna represented a significant variation in long-term temporal scale during the study period. The average taxonomic distinctness indices (??+) decreased to a significantly low level, while the variation in taxonomic distinctness measures (??+) increased to a significantly high level compared with the expected values from 1989 to 1998. The pairwise indices of ??+ and (??+) showed a decreasing and increasing trend of departure from the expected taxonomic breadth in response to the environmental stress and anthropogenic impact, respectively. These results imply that the ecological quality status has been significantly deteriorated due to the increasing environmental stress and anthropogenic impact in intertidal zones of the Yellow Sea, northern China, and that the taxonomic distinctness indices of macroinvertebrate fauna are a robust indicator for evaluating ecological quality status.  相似文献   

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