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561.
Victoria F. Griffiths Joseph W. Bull Julia Baker E.J. Milner-Gulland 《Conservation biology》2019,33(1):76-87
Governments, businesses, and lenders worldwide are adopting an objective of no net loss (NNL) of biodiversity that is often partly achieved through biodiversity offsetting within a hierarchy of mitigation actions. Offsets aim to balance residual losses of biodiversity caused by development in one location with commensurate gains at another. Although ecological challenges to achieve NNL are debated, the associated gains and losses for local stakeholders have received less attention. International best practice calls for offsets to make people no worse off than before implementation of the project, but there is a lack of clarity concerning how to achieve this with regard to people's use and nonuse values for biodiversity, especially given the inevitable trade-offs when compensating biodiversity losses with gains elsewhere. This is particularly challenging for countries where poor people depend on natural resources. Badly planned offsets can exacerbate poverty, and development and offset impacts can vary across spatial-temporal scales and by location, gender, and livelihood. We conceptualize the no-worse-off principle in the context of NNL of biodiversity, by exploring for whom and how the principle can be achieved. Changes in the spatial and temporal distribution of biodiversity-related social impacts of a development and its associated offset can lead to social inequity and negatively impact people's well-being. The level of aggregation (regional, village, interest group, household, and individual) at which these social impacts are measured and balanced can again exacerbate inequity in a system. We propose that a determination that people are no worse off, and preferably better off, after a development and biodiversity offset project than they were before the project should be based on the perceptions of project-affected people (assessed at an appropriate level of aggregation); that their well-being associated with biodiversity losses and gains should be at least as good as it was before the project; and that this level of well-being should be maintained throughout the project life cycle. Employing this principle could help ensure people are no worse off as a result of interventions to achieve biodiversity NNL. 相似文献
562.
Ge Sun Devendra M. Amatya Steven G. McNulty R. Wayne Skaggs Joseph H. Hughes 《Journal of the American Water Resources Association》2000,36(2):367-374
ABSTRACT: There are increasing concerns in the forestry community about global climate change and variability associated with elevated atmospheric CO2. Changes in precipitation and increases in air temperature could impose additional stress on forests during the next century. For a study site in Carteret County, North Carolina, the General Circulation Model, HADCM2, predicts that by the year 2099, maximum air temperature will increase 1.6 to 1.9°C, minimum temperature will increase 2.5 to 2.8°C, and precipitation will increase 0 to 10 percent compared to the mid‐1990s. These changes vary from season to season. We utilized a forest ecosystem process model, PnET‐II, for studying the potential effects of climate change on drainage outflow, evapotranspiration, leaf area index (LAI) and forest Net Primary Productivity (NPP). This model was first validated with long term drainage and LAI data collected at a 25‐ha mature loblolly pine (Pinus taeda L.) experimental watershed located in the North Carolina lower coastal plain. The site is flat with poorly drained soils and high groundwater table. Therefore, a high field capacity of 20 cm was used in the simulation to account for the topographic effects. This modeling study suggested that future climate change would cause a significant increase of drainage (6 percent) and forest productivity (2.5 percent). Future studies should consider the biological feedback (i.e., stomata conductance and water use efficiency) to air temperature change. 相似文献
563.
Yiliang He Bin Zhao Joseph B. Hughes Sung Soo Han 《Frontiers of Environmental Science & Engineering》2008,2(3):326-332
The performances and kinetic parameters of Fenton oxidation of 2,4- and 2,6-dinitrotoluene (DNT) in water-acetone mixtures and explosive contaminated soil washing-out solutions were investigated at a laboratory scale. The experimental results show that acetone can be a significant hydroxyl radical scavenger and result in serious inhibition of Fenton oxidation of 2,4- and 2,6-DNT. Although no serious inhibition was found in contaminated soil washing-out solutions, longer reaction time was needed to remove 2,4- and 2,6-DNT completely, mainly due to the competition of hydroxyl radicals. Fenton oxidation of 2,4- and 2,6-DNT fit well with the first-order kinetics and the presence of acetone also reduced DNT’s degradation kinetics. Based on the comparison and matching of retention time and ultraviolet (UV) spectra between high performance liquid chromatography (HPLC) and standards, the following reaction pathway for 2,4-DNT primary degradation was proposed: 2,4-DNT → 2,4-dinitro-benzaldehyde → 2,4-dinitrobenzoic acid → 1,3-dinitrobenzene → 3-nitrophenol. 相似文献
564.
Wusi Yue Charles Meneveau Marc B. Parlange Weihong Zhu Hyung Suk Kang Joseph Katz 《Environmental Fluid Mechanics》2008,8(1):73-95
A comparative study of turbulence in a wind-tunnel model canopy is performed, using Large eddy simulation (LES) and experimental
data from PIV and hot-wire anemometry measurements. The model canopy is composed of thin cylindrical stalks. In the LES, these
are represented using a plant-scale approach, while the scale-dependent Lagrangian dynamic model is used as subgrid-scale
model. LES predictions of turbulence statistics and energy spectra are found to be in good agreement with the experimental
data. Turbulent kinetic energy (TKE) budgets from the LES simulation are analyzed to provide more information absent in the
measurements. Results confirm that sloshing motions at the low levels of the canopy are mainly driven by pressure fluctuations.
A difference between the energy flux obtained from the energy spectrum and the SGS dissipation rate is observed, consistent
with a spectral bypass mechanism in which the real spectral flux due to cascade is smaller than that implied by the energy-spectrum
level, due to direct drain by the canopy. 相似文献
565.
Nnanake‐Abasi O. Offiong Edu J. Inam Helen S. Etuk Joseph P. Essien 《补救:环境净化治理成本、技术与工艺杂志》2019,30(1):65-75
Polycyclic aromatic hydrocarbons (PAHs) are among the world's most significant environmental organic contaminants because of their carcinogenic properties. PAHs are widely distributed globally as a result of releases from numerous natural and anthropogenic activities. Consequently, several PAH monitoring studies have been conducted and remediation approaches explored. This article aims to provide the current status of PAH distribution in Nigeria's oil and gas industrial region in relation to the technologies adopted for PAH remediation. Ideally, the findings will provide insight into the challenges in managing organic contaminants derived from petroleum exploration activities in developing countries with Nigeria as a case study. 相似文献
566.
Marie-Eve Dubuis Hamza M’Bareche Marc Veillette Bouchra Bakhiyi Joseph Zayed Jacques Lavoie 《Journal of the Air & Waste Management Association (1995)》2017,67(11):1258-1271
This study sought to fill the gap in information about the type and the concentration of bioaerosols present in the air of biomethanization facilities (BF). Evaluation of bioaerosol composition and concentration was achieved in two biomethanization facilities located in Eastern Canada, during summer and winter. In order to have a thorough understanding of the studied environment, the methodology combined culture of bacteria and molds, qualitiative polymerase chain reaction (qPCR) for specific microorganisms, endotoxin quantification, and next-generation sequencing (NGS) for bacterial diversity. Results revealed that workers in biomethanization facilities are exposed to bioaerosols and pathogenic microorganisms similar to those found in composting plants. However, human exposure levels to bioaerosols are lower in BF than in composting plants. Despite these differences, use of personal protective equipment is recommended to lower the risks of health problems.
Implications: Biomethanization is a new technology used in eastern Canada for waste management. In the next few years, it is expected that there will be an expansion of facilities in response of tight governmental regulations. Workers in biomethanization facilities are exposed to various amounts of bioaerosols composed of some harmful microorganisms. Therefore, monitoring this occupational exposure could be an interesting tool for improving worker’s health. 相似文献
567.
Benefit‐Cost Analysis of Integrated Water Resource Management: Accounting for Interdependence in the Yakima Basin Integrated Plan
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Jonathan Yoder Jennifer Adam Michael Brady Joseph Cook Stephen Katz Shane Johnston Keyvan Malek John McMillan Qingqing Yang 《Journal of the American Water Resources Association》2017,53(2):456-477
Integrated water resource management (IWRM) requires accounting for many interrelated facets of water systems, water uses and stakeholders, and water management activities. The consequence is that project analysis must account for the nonseparability among the component parts of IWRM plans. This article presents a benefit‐cost (B‐C) analysis of a set of projects included in the Yakima Basin Integrated Plan proposed for the Yakima Basin in south‐central Washington State. The analysis accounts for interdependence among proposed water storage projects and between water storage and water market development in the context of historical and more adverse projected future climate scenarios. Focusing on irrigation benefits from storage, we show that the value of a given proposed storage project is lower when other proposed storage projects in the basin are implemented, and when water markets are functioning effectively. We find that none of the water storage projects satisfy a B‐C criterion, and that assuring proposed instream flow augmentation is less expensive by purchasing senior diversion rights than relying on new storage to provide it. 相似文献
568.
The repurposing of military lands is common in many parts of the world and presents a variety of conservation opportunities. This study examines land cover at Big Oaks National Wildlife Refuge, Indiana (U.S.A.) as it transitioned from military proving ground to wildlife refuge from 1985 to 2013. We use remote sensing, semi-structured interviews, and a review of planning and management documents to examine this transition. Limited change in land cover composition and distribution are detected, despite changes in use and management. This landscape similarity relates to similarities in land management practices, and the impact of landscape history on current management practices. The findings suggest that military use and conservation objectives at this site yield similar land covers and are not necessarily in contrast to each other. As military base closures continue, the potential to maintain and expand conservation opportunities on these lands will likely grow in importance. 相似文献
569.
Shanon Donnelly Ishmael Cobbinah Wilson Joseph Oduro Appiah 《Journal of Land Use Science》2017,12(5):338-350
The emergent patterns of land change resulting from the development of shale oil and gas infrastructure is a result of many small decisions and interactions. This research focuses on the land change associated with the development of shale oil and gas infrastructure in the Marcellus and Utica shale formations in two geographically proximate and physically similar counties, Carroll County, OH, and Washington County, PA. Land-cover data used to measure feature-scale change were digitized from aerial photography and then used to update National Land Cover Dataset data used in the calculation of forest fragmentation for the entire study areas. The amount and pattern of land change was very similar between the two counties even though they are drawing oil and gas from different shale formations. Less than 1% of the total forest for each county was lost but the fragmentation impacts are amplified by the pattern of infrastructure on the landscape. 相似文献
570.
Woonsup Choi Sangjun Kang Jinmu Choi Joseph James Larsen ChungWeon Oh Yu-gyung Na 《Regional Environmental Change》2017,17(2):379-388
There has been a significant lack of land cover change studies in relation to deforestation in the Democratic People’s Republic of Korea (North Korea). The purpose of this study is to characterize deforestation in North Korea through land cover change trajectory and spatial analysis. We used three 30-m gridded land cover data sets for North Korea representing the conditions of the late 1980s, 1990s, and 2000s, respectively, as well as a digital elevation model. We examined the land cover trajectories during the two decades, i.e., which land cover became which at the pixel level. In addition, we calculated topographic characteristics of deforested pixels. Major findings from the study are summarized as follows: (1) net forest loss in North Korea was negligible in the latter decade compared to the former (>5000 km2), whereas other land cover changes were still active; (2) as a result of deforestation, forest land cover became mostly agricultural, particularly in the latter decade (95 %); (3) expansion of agricultural land cover continued during the time, increasing by >42 %; and (4) elevation and slope of deforested areas decreased slightly in the latter decade. The key contribution of the study is that it has demonstrated which land cover became which at the 30-m pixel level, complementing existing studies that examined overall forest stock in North Korea. 相似文献