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871.
Increasingly government agencies are seeking to quantify the outcomes of proposed policy options in terms of ecosystem service
benefits, yet conflicting definitions and ad hoc approaches to measuring ecosystem services have created confusion regarding
how to rigorously link ecological change to changes in human well-being. Here, we describe a step-by-step framework for producing
ecological models and metrics that can effectively serve an economic-benefits assessment of a proposed change in policy or
management. A focus of the framework is developing comparable units of ecosystem goods and services to support decision-making,
even if outcomes cannot be monetized. Because the challenges to translating ecological changes to outcomes appropriate for
economic analyses are many, we discuss examples that demonstrate practical methods and approaches to overcoming data limitations.
The numerous difficult decisions that government agencies must make to fairly use and allocate natural resources provides
ample opportunity for interdisciplinary teams of natural and social scientists to improve methods for quantifying changes
in ecosystem services and their effects on human well-being. This framework is offered with the intent of promoting the success
of such teams as they support managers in evaluating the equivalency of ecosystem service offsets and trades, establishing
restoration and preservation priorities, and more generally, in developing environmental policy that effectively balances
multiple perspectives. 相似文献
872.
García-Llorente M Martín-López B Nunes PA González JA Alcorlo P Montes C 《Environmental management》2011,48(3):418-435
Biological invasions occur worldwide, and have been the object of ecological and socio-economic research for decades. However, the manner in which different stakeholder groups identify the problems associated with invasive species and confront invasive species management under different policies remains poorly understood. In this study, we conducted an econometric analysis of the social factors influencing willingness to pay for invasive alien species management under two different regimes: eradication and prevention in the Doñana Natural Protected Area (SW Spain). Controlling for the participation of local residents, tourists and conservationists, email and face-to-face questionnaires were conducted. Results indicated that respondents were more willing to pay for eradication than prevention; and public support for invasive alien species management was influenced by an individual’s knowledge and perception of invasive alien species, active interest in nature, and socio-demographic attributes. We concluded that invasive alien species management research should confront the challenges to engage stakeholders and accept any tradeoffs necessary to modify different conservation policies to ensure effective management is implemented. Finally, our willingness to pay estimates suggest the Department of Environment of Andalusian Government has suitable social support to meet the budgetary expenditures required for invasive alien species plans and adequate resources to justify an increase in the invasive alien species management budget. 相似文献
873.
Anthropogenic impairment of water bodies represents a global environmental concern, yet few attempts have successfully linked
fish performance to thermal habitat suitability and fewer have distinguished co-varying water quality constraints. We interfaced
fish bioenergetics, field measurements, and Thermal Remote Imaging to generate a spatially-explicit, high-resolution surface
of fish growth potential, and next employed a structured hypothesis to detect relationships among measures of fish performance
and co-varying water quality constraints. Our thermal surface of fish performance captured the amount and spatial-temporal
arrangement of thermally-suitable habitat for three focal species in an extremely heterogeneous reservoir, but interpretation
of this pattern was initially confounded by seasonal covariation of water residence time and water quality. Subsequent path
analysis revealed that in terms of seasonal patterns in growth potential, catfish and walleye responded to temperature, positively
and negatively, respectively; crappie and walleye responded to eutrophy (negatively). At the high eutrophy levels observed
in this system, some desired fishes appear to suffer from excessive cultural eutrophication within the context of elevated
temperatures whereas others appear to be largely unaffected or even enhanced. Our overall findings do not lead to the conclusion
that this system is degraded by pollution; however, they do highlight the need to use a sensitive focal species in the process
of determining allowable nutrient loading and as integrators of habitat suitability across multiple spatial and temporal scales.
We provide an integrated approach useful for quantifying fish growth potential and identifying water quality constraints on
fish performance at spatial scales appropriate for whole-system management. 相似文献
874.
Development of Customized Fire Behavior Fuel Models for Boreal Forests of Northeastern China 总被引:2,自引:1,他引:2
Knowledge of forest fuels and their potential fire behavior across a landscape is essential in fire management. Four customized
fire behavior fuel models that differed significantly in fuels characteristics and environmental conditions were identified
using hierarchical cluster analysis based on fuels data collected across a boreal forest landscape in northeastern China.
Fuel model I represented the dense and heavily branched Pinus pumila shrubland which has significant fine live woody fuels. These forests occur mainly at higher mountain elevations. Fuel model
II is applicable to forests dominated by Betula platyphylla and Populus davidiana occurring in native forests on hill slopes or at low mountain elevations. This fuel model was differentiated from other fuel
models by higher herbaceous cover and lower fine live woody loading. The primary coniferous forests dominated by Larix gmelini and Pinus sylvestris L. var. mongolica were classified as fuel model III and fuel model IV. Those fuel models differed from one another in average cover and height
of understory shrub and herbaceous layers as well as in aspect. The potential fire behavior for each fuel model was simulated
with the BehavePlus5.0 fire behavior prediction system. The simulation results indicated that the Pinus pumila shrubland fuels had the most severe fire behavior for the 97th percentile weather condition, and had the least severe fire
behavior under 90th percentile weather condition. Fuel model II presented the least severe fire potential across weather conditions.
Fuel model IV resulted in greater fire severity than Fuel model III across the two weather scenarios that were examined. 相似文献
875.
876.
South Korea’s Civilian Control Zone (CCZ), a relatively untouched area due to tight military oversight since the end of Korean
War, has received considerable attention nationally and internationally for its rich biodiversity. However, the exclusion
of local communities from the process of defining problems and goals and of setting priorities for biodiversity conservation
has halted a series of biodiversity conservation efforts. Through qualitative research, we explored CCZ farmers’ views of
key problems and issues and also the sources of their opposition to the government-initiated conservation approaches. Key
findings include the farmers’ concerns about the impact of conservation restrictions on their access to necessary resources
needed to farm, wildlife impacts on the value of rice and other agricultural goods they produce, and farmers’ strong distrust
of government, the military, and planners, based on their experiences with past conservation processes. The findings regarding
farmers’ perceptions should prove useful for the design of future participatory planning processes for biodiversity conservation
in the CCZ. This case highlights how conservative measures, perceived to be imposed from above—however scientifically valuable—can
be undermined and suggests the value that must be placed on communication among planners and stakeholders. 相似文献
877.
Assessing the impact of climate change on species and associated management objectives is a critical initial step for engaging
in the adaptation planning process. Multiple approaches are available. While all possess limitations to their application
associated with the uncertainties inherent in the data and models that inform their results, conducting and incorporating
impact assessments into the adaptation planning process at least provides some basis for making resource management decisions
that are becoming inevitable in the face of rapidly changing climate. Here we provide a non-exhaustive review of long-standing
(e.g., species distribution models) and newly developed (e.g., vulnerability indices) methods used to anticipate the response
to climate change of individual species as a guide for managers grappling with how to begin the climate change adaptation
process. We address the limitations (e.g., uncertainties in climate change projections) associated with these methods, and
other considerations for matching appropriate assessment approaches with the management questions and goals. Thorough consideration
of the objectives, scope, scale, time frame and available resources for a climate impact assessment allows for informed method
selection. With many data sets and tools available on-line, the capacity to undertake and/or benefit from existing species
impact assessments is accessible to those engaged in resource management. With some understanding of potential impacts, even
if limited, adaptation planning begins to move toward the development of management strategies and targeted actions that may
help to sustain functioning ecosystems and their associated services into the future. 相似文献
878.
The management of small-scale freshwater fisheries in Amazon has been based usually on surveys of urban markets, while fisheries
of rural villages have gone unnoticed. We compared the fishing characteristics (catch, effort and selectivity) between an
urban market and five small villages in the Lower Tocantins River (Brazilian Amazon), downstream from a large reservoir. We
recorded 86 and 601 fish landings in the urban market and villages, respectively, using the same methodology. The urban fishers
showed higher catch per unit of effort, higher amount of ice (related to a higher fishing effort, as ice is used to store
fish catches) and larger crew size per fishing trip, but village fishers had a higher estimated annual fish production. Conversely,
urban and village fishers used similar fishing gear (gillnets) and the main fish species caught were the same. However, village
fishers showed more diverse strategies regarding gear, habitats and fish caught. Therefore, although it underestimated the
total amount of fish caught in the Lower Tocantins River region, the data from the urban market could be a reliable indicator
of main fish species exploited and fishing gear used by village fishers. Monitoring and management should consider the differences
and similarities between urban and rural fisheries, in Amazon and in other tropical regions. 相似文献
879.
Three different systems of designating protected areas in a Mediterranean region in southeastern Spain were studied, referring
to their effectiveness and efficiency for protecting both the breeding territories and the suitable habitat of a set of ten
raptor species. Taking into consideration the varying degrees of endangerment of these species, a map of multispecies conservation
values was also drawn up and superimposed on the three protected-area systems studied. In order to compare the levels of protection
afforded by the three systems, we considered two indices that measured their relative effectiveness and efficiency. The effectiveness
estimated the proportion of territories or optimal habitat protected by the networks while efficiency implicitly considered
the area of each system (percentage of breeding territories or optimal habitat protected per 1% of land protected). Overall,
our results showed that the most efficient system was that formed by the set of regional parks and reserves (17 protected
breeding territories per 100 km2), although, given its small total area, it was by far the least effective (only protecting the 21% of the breeding territories
of all species and 17% of the area of high conservation value). The systems formed by the Special Protection Areas (designated
under the EU “Birds Directive”) and by the Special Conservation Areas (designated under the EU “Habitats Directive”) notably
increased the percentages of protected territories of all species (61%) and area of high conservation value (57%), but their
efficiency was not as high as expected in most cases. The overall level of protection was high for all species except for
the Lesser Kestrel (Falco naumanni), an endangered falcon that inhabits pseudo-steppe and traditional agricultural habitats, which are clearly underrepresented
in the protected-area network of the study region. 相似文献
880.
Rosenfeld J Hogan D Palm D Lundquist H Nilsson C Beechie TJ 《Environmental management》2011,47(1):28-39
Sediment size and supply exert a dominant control on channel structure. We review the role of sediment supply in channel structure,
and how regional differences in sediment supply and landuse affect stream restoration priorities. We show how stream restoration
goals are best understood within a common fluvial geomorphology framework defined by sediment supply, storage, and transport.
Landuse impacts in geologically young landscapes with high sediment yields (e.g., coastal British Columbia) typically result
in loss of instream wood and accelerated sediment inputs from bank erosion, logging roads, hillslopes and gullies. In contrast,
northern Sweden and Finland are landscapes with naturally low sediment yields caused by low relief, resistant bedrock, and
abundant mainstem lakes that act as sediment traps. Landuse impacts involved extensive channel narrowing, removal of obstructions,
and bank armouring with boulders to facilitate timber floating, thereby reducing sediment supply from bank erosion while increasing
export through higher channel velocities. These contrasting landuse impacts have pushed stream channels in opposite directions
(aggradation versus degradation) within a phase-space defined by sediment transport and supply. Restoration in coastal British
Columbia has focused on reducing sediment supply (through bank and hillslope stabilization) and restoring wood inputs. In
contrast, restoration in northern Fennoscandia (Sweden and Finland) has focused on channel widening and removal of bank-armouring
boulders to increase sediment supply and retention. These contrasting restoration priorities illustrate the consequences of
divergent regional landuse impacts on sediment supply, and the utility of planning restoration activities within a mechanistic
sediment supply-transport framework. 相似文献