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971.
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
972.
Oil is the world’s primary source of non-renewable energy, and it has also contaminated ocean coastlines due to spills. It
is therefore important to have remediation treatments that are both effective, and ecologically not harmful. Current in situ
bioremediation methods consist primarily of biostimulation, through addition of nutrients, and bioaugmentation, the addition
of hydrocarbon degrading microorganisms. The purpose of this article is to discuss successful and unsuccessful remediation
through the use of biostimulation, bioaugmentation, or a combination of both. As microbial treatments are capable of enhancing
coastal oil remediation in temperate and tropical settings, the success of a particular remediation approach will be determined
based on the type and amount of oil, type of soil and/or sediment, microbial inoculants and the often changing physical, chemical
and biological environmental conditions. Environmental factors and limitations will be discussed as to why certain bioremediation
events were successful while others were not. 相似文献
973.
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
974.
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
975.
976.
Nasution MA Yaakob Z Ali E Tasirin SM Abdullah SR 《Journal of environmental quality》2011,40(4):1332-1339
Palm oil mill effluent (POME) is highly polluting wastewater generated from the palm oil milling process. Palm oil mill effluent was used as an electrolyte without any additive or pretreatment to perform electrocoagulation (EC) using electricity (direct current) ranging from 2 to 4 volts in the presence of aluminum electrodes with a reactor volume of 20 L. The production of hydrogen gas, removal of chemical oxygen demand (COD), and turbidity as a result of electrocoagulation of POME were determined. The results show that EC can reduce the COD and turbidity of POME by 57 and 62%, respectively, in addition to the 42% hydrogen production. Hydrogen production was also helpful to remove the lighter suspended solids toward the surface. The production of Al(OH)XHO at the aluminum electrode (anode) was responsible for the flocculation-coagulation process of suspended solids followed by sedimentation under gravity. The production of hydrogen gas from POME during EC was also compared with hydrogen gas production by electrolysis of tap water at pH 4 and tap water without pH adjustment under the same conditions. The main advantage of this study is to produce hydrogen gas while treating POME with EC to reduce COD and turbidity effectively. 相似文献
977.
Soils adjacent to chromated copper arsenate (CCA)-treated fence posts along a fence line transecting different soil series, parent material, drainage classes, and slope were used to determine which soil properties had the most influence on As spatial distribution and speciation. Metal distribution was evaluated at macroscopic (total metal concentration contour maps) and microscopic scales (micro-synchrotron X-ray fluorescence maps), As speciation was determined using extended X-ray absorption fine structure spectroscopy, and redox status and a myriad of other basic soil properties were elucidated. All geochemical parameters measured point to a condition in which the mobilization of As becomes more favorable moving down the topographic gradient, likely resulting through competition (Meh-P, SOM), neutral or slightly basic pH, and redox conditions that are favorable for As mobilization (higher Fe(II) and total-Fe concentrations in water extracts). On the landscape scale, with hundreds of kilometers of fence, the arsenic loading into the soil can be substantial (~8-12 kg km). Although a significant amount of the As is stable, extended use of CCA-treated wood has resulted in elevated As concentrations in the local environment, increasing the risk of exposure and ecosystem perturbation. Therefore, a move toward arsenic-free alternatives in agricultural applications for which it is currently permitted should be considered. 相似文献
978.
Agroforestry, the deliberate integration of trees into agricultural operations, sequesters carbon (C) while providing valuable services on agricultural lands. However, methods to quantify present and projected C stocks in these open-grown woody systems are limited. As an initial step to address C accounting in agroforestry systems, a spatial Markov random field model for predicting the natural logarithm (log) of the mean aboveground volume of green ash ( Marsh.) within a shelterbelt, referred to as the log of aboveground volume, was developed using data from an earlier study and web-available soil and climate information. Windbreak characteristics, site, and climate variables were used to model the large-scale trend of the log of aboveground volume. The residuals from this initial model were correlated among sites up to 24 km from a point of interest. Therefore, a spatial dependence parameter was used to incorporate information from sites within 24 km into the prediction of the log of the aboveground volume. Age is an important windbreak characteristic in the model. Thus, the log of aboveground volume can be predicted for a given windbreak age and for values of other explanatory variables associated with a site of interest. Such predictions can be exponentiated to obtain predictions of aboveground volume for windbreaks without repeated inventory. With the capability of quantifying uncertainty, the model has the potential for large regional planning efforts and C stock assessments for many deciduous tree species used in windbreaks and riparian buffers once it is calibrated. 相似文献
979.
Adaptive management for a turbulent future 总被引:3,自引:0,他引:3
Allen CR Fontaine JJ Pope KL Garmestani AS 《Journal of environmental management》2011,92(5):1339-1345
The challenges that face humanity today differ from the past because as the scale of human influence has increased, our biggest challenges have become global in nature, and formerly local problems that could be addressed by shifting populations or switching resources, now aggregate (i.e., "scale up") limiting potential management options. Adaptive management is an approach to natural resource management that emphasizes learning through management based on the philosophy that knowledge is incomplete and much of what we think we know is actually wrong. Adaptive management has explicit structure, including careful elucidation of goals, identification of alternative management objectives and hypotheses of causation, and procedures for the collection of data followed by evaluation and reiteration. It is evident that adaptive management has matured, but it has also reached a crossroads. Practitioners and scientists have developed adaptive management and structured decision making techniques, and mathematicians have developed methods to reduce the uncertainties encountered in resource management, yet there continues to be misapplication of the method and misunderstanding of its purpose. Ironically, the confusion over the term "adaptive management" may stem from the flexibility inherent in the approach, which has resulted in multiple interpretations of "adaptive management" that fall along a continuum of complexity and a priori design. Adaptive management is not a panacea for the navigation of 'wicked problems' as it does not produce easy answers, and is only appropriate in a subset of natural resource management problems where both uncertainty and controllability are high. Nonetheless, the conceptual underpinnings of adaptive management are simple; there will always be inherent uncertainty and unpredictability in the dynamics and behavior of complex social-ecological systems, but management decisions must still be made, and whenever possible, we should incorporate learning into management. 相似文献
980.
Adeli A Shankle MW Tewolde H Brooks JP Sistani KR McLaughlin MR Rowe DE 《Journal of environmental quality》2011,40(2):566-574
Surface application of broiler litter to no-till cotton could lead to degradation of water quality. Incorporation of broiler litter into the top surface soil (0.05 m) could alleviate this risk. A 2-yr field study was conducted on a silt loam upland soil to determine the effect of incorporation of broiler litter into the soil surface on nutrient and bacterial transport in runoff. The experimental design was a randomized complete block with four treatments and three replications. Treatments were (i) unfertilized control; (ii) surface-appliedbroiler litter at 7.8 Mg ha(-1) without incorporation; (iii) surface-applied broiler litter at 7.8 Mg ha(-1) with immediate incorporation; and (iv) inorganic fertilizer N (urea ammonium nitrate, 32% N) and inorganic fertilizer P (triple superphosphate) at the recommended rate. Phosphorus was surface appliedat 25 kg ha(-1) and N was injected at 101 kg ha(-1) into the soil using a commercial liquid fertilizer applicator. Runoff was collected from small runoff plots (2.4 m by 1.6 m) established at the bottom side of main plots (13.7 m by 6.0 m). Incorporation of broiler litter reduced total N (TN), NO3-N, water soluble P (WSP), and total P (TP) concentrations in runoffby 35, 25, 61, and 64%, respectively, and litter-associated bacteria by two to three orders of magnitude compared with unincorporated treatment. No significant difference in total suspended solids (TSS) in runoffwas obtained between incorporated and unincorporated treatments. Incorporation of broiler litter into the surface soil in the no-till system immediately after application minimized the potential risk for surface nutrient losses and bacteria transport in runoff. 相似文献