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871.
Pasqualini V Oberti P Vigetta S Riffard O Panaïotis C Cannac M Ferrat L 《Environmental management》2011,48(1):38-56
Forest management can benefit from decision support tools, including GIS-based multicriteria decision-aiding approach. In
the Mediterranean region, Pinus pinaster forests play a very important role in biodiversity conservation and offer many socioeconomic benefits. However, the conservation
of this species is affected by the increase in forest fires and the expansion of Matsucoccus feytaudi. This paper proposes a methodology based on commonly available data for assessing the values and risks of P. pinaster forests and to generating maps to aid in decisions pertaining to fire and phytosanitary risk management. The criteria for
assessing the values (land cover type, legislative tools for biodiversity conservation, environmental tourist sites and access
routes, and timber yield) and the risks (fire and phytosanitation) of P. pinaster forests were obtained directly or by considering specific indicators, and they were subsequently aggregated by means of GIS-based
multicriteria analysis. This approach was tested on the island of Corsica (France), and maps to aid in decisions pertaining
to fire risk and phytosanitary risk (M. feytaudi) were obtained for P. pinaster forest management. Study results are used by the technical offices of the local administration—Corsican Agricultural and Rural Development Agency (ODARC)—for planning the conservation of P. pinaster forests with regard to fire prevention and safety and phytosanitary risks. The decision maker took part in the evaluation
criteria study (weight, normalization, and classification of the values). Most suitable locations are given to target the
public intervention. The methodology presented in this paper could be applied to other species and in other Mediterranean
regions. 相似文献
872.
Forests are a major terrestrial ecosystem providing multiple ecosystem services. However, the importance of forests is frequently
underestimated from an economic perspective because of the externalities and public good properties of these services. Forest
eco-compensation is a transfer mechanism that serves to internalize the externalities of forest ecosystem services by compensating
individuals or companies for the losses or costs resulting from the provision of these services. China’s current forest eco-compensation
system is centered mainly on noncommercial forest. The primary measures associated with ecosystem services are (1) a charge
on destructive activities, such as indiscriminate logging, and (2) compensation for individual or local activities and investments
in forest conservation. The Compensation Fund System for Forest Ecological Benefits was first listed in the Forest Law of the People’s Republic of China in 1998. In 2004, the Central Government Financial Compensation Fund, an important source for the Compensation Fund for Forest
Ecological Benefits, was formally established. To improve the forest eco-compensation system, it is crucial to design and
establish compensation criteria for noncommercial forests. These criteria should take both theoretical and practical concerns
into account, and they should be based on the quantitative valuation of ecosystem services. Although some initial headway
has been made on this task, the implementation of an effective forest eco-compensation system in China still has deficiencies
and still faces problems. Implementing classification-based and dynamic management for key noncommercial forests and establishing
an eco-compensation mechanism with multiple funding sources in the market economy are the key measures needed to conquer these
problems and improve the forest eco-compensation system and China’s forestry development in sequence. 相似文献
873.
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
874.
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
875.
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
876.
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
877.
With 207 million ha of forest covering 22% of its land area, China ranks fifth in the world in forest area. Rapid economic
growth, climate change, and forest disturbances pose new, complex challenges for forest research and management. Progress
in meeting these challenges is relevant beyond China, because China’s forests represent 34% of Asia’s forests and 5% of the
worlds’ forests. To provide a broader understanding of these management challenges and of research and policies that address
them, we organized this special issue on contemporary forest research and management issues in China. At the national level,
papers review major forest types and the evolution of sustainable forestry, the development of China’s forest-certification
efforts, the establishment of a forest inventory system, and achievements and challenges in insect pest control in China.
Papers focused on Northern China address historical, social, and political factors that have shaped the region’s forests;
the use of forest landscape models to assess how forest management can achieve multiple objectives; and analysis and modeling
of fuels and fire behavior. Papers addressing Central and South China describe the “Grain for Green” program, which converts
low productivity cropland to grassland and woodland to address erosion and soil carbon sequestration; the potential effects
of climate change on CO2 efflux and soil respiration; and relationships between climate and net primary productivity. China shares many forest management
and research issues with other countries, but in other cases China’s capacity to respond to forest management challenges is
unique and bears watching by the rest of the world. 相似文献
878.
Shana Sampaio Sieber Patrícia Muniz Medeiros Ulysses Paulino Albuquerque 《Journal of Agricultural and Environmental Ethics》2011,24(5):511-531
The diversity of plant resources in the Brazilian semi-arid region is being compromised by practices related to agriculture,
pastures, and forest harvesting, especially in areas containing Caatinga vegetation (xeric shrublands and thorn forests).
The impact of these practices constitutes a series of complex factors involving local issues, creating a need for further
scientific studies on the social-environmental dynamics of natural resource use. Through participatory methods, the present
study analyzed people’s representations about local environmental change processes in the Brazilian semi-arid region, taking
into consideration local production systems, natural resources, and their importance. Environmental historical graphs were
developed with nine local families to analyze landscape changes with regard to cultivated areas and pastures, and their relationship
with the availability of native vegetation. Punctuation exercises were performed to observe the importance of each unit that
supplied native and cultivated resources. The availability of native resources in the environment is subject to stability,
as observed by a majority of the local families. The role of the production units (crops and pastures) was emphasized by most
families in the study, especially because of the need for products for subsistence needs and income generation. The current
decline of such practices is a consequence of an exodus of field workers and also relates to the conservation of native species
that otherwise would have been deforested in favor of agricultural practices. 相似文献
879.
Rita JC Gama-Rodrigues EF Gama-Rodrigues AC Polidoro JC Machado RC Baligar VC 《Environmental management》2011,48(1):134-141
Agroforestry systems (AFSs) have an important role in capturing above and below ground soil carbon and play a dominant role
in mitigation of atmospheric CO2. Attempts has been made here to identify soil organic matter fractions in the cacao-AFSs that have different susceptibility
to microbial decomposition and further represent the basis of understanding soil C dynamics. The objective of this study was
to characterize the organic matter density fractions and soil size fractions in soils of two types of cacao agroforestry systems
and to compare with an adjacent natural forest in Bahia, Brazil. The land-use systems studied were: (1) a 30-year-old stand
of natural forest with cacao (cacao cabruca), (2) a 30-year-old stand of cacao with Erythrina glauca as shade trees (cacao + erythrina), and (3) an adjacent natural forest without cacao. Soil samples were collected from 0-10 cm
depth layer in reddish-yellow Oxisols. Soil samples was separated by wet sieving into five fraction-size classes (>2000 μm,
1000–2000 μm, 250–1000 μm, 53–250 μm, and <53 μm). C and N accumulated in to the light (free- and intra-aggregate density
fractions) and heavy fractions of whole soil and soil size fraction were determined. Soil size fraction obtained in cacao
AFS soils consisted mainly (65 %) of mega-aggregates (>2000 μm) mixed with macroaggregates (32–34%), and microaggregates (1–1.3%).
Soil organic carbon (SOC) and total N content increased with increasing soil size fraction in all land-use systems. Organic
C-to-total N ratio was higher in the macroaggregate than in the microaggregate. In general, in natural forest and cacao cabruca
the contribution of C and N in the light and heavy fractions was similar. However, in cacao + erythrina the heavy fraction
was the most common and contributed 67% of C and 63% of N. Finding of this study shows that the majority of C and N in all
three systems studied are found in macroaggregates, particularly in the 250–1000 μm size aggregate class. The heavy fraction
was the most common organic matter fraction in these soils. Thus, in mature cacao AFS on highly weathered soils the main mechanisms
of C stabilization could be the physical protection within macroaggregate structures thereby minimizing the impact of conversion
of forest to cacao AFS. 相似文献
880.