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821.
There is concern that elevated levels of selenium found in the source water of a newly formed wetland park in Las Vegas, Nevada,
may have detrimental effects on local wildlife. In this study, we collected and analyzed water samples monthly for a three
year period from the inflow and outflow of the system. We also gathered dominant aquatic plants and selected terrestrial plants
and analyzed the water and plant tissues (root, shoot, leaf and flower) for selenium by high resolution Inductively Coupled
Plasma Mass Spectrometer. Except for storm events and the introduction of an alternative low selenium content source water
during summer low-flow conditions, selenium in the water was relatively stable. The concentration in the outflow tended to
be slightly lower than the inflow. Concentrations of selenium in the dominant plant taxa in this wetlands were typical of
ecosystems in the western United States and varied by taxa, tissue type, localized conditions (e.g., contact with selenium-laden
water), and to a lesser extent, seasons. Selenium in the aquatic plant spiny naiad (Najas marina) was relatively high and may pose an ecological risk to wildlife during the late spring and summer. Additional work is underway
investigating aquatic food chain accumulations of selenium as well as mass balance of selenium in the system. 相似文献
822.
Economic Development and Conservation of Biological and Cultural Diversity in Yunnan Province, China
Rey C. Stendell Richard L. Johnson John P. Mosesso Xia Zhang 《Environment, Development and Sustainability》2000,2(3-4):333-345
Chinese and American scientists are co-operating to develop concepts, strategies, agreements, and proposals in support of an economic development and sustainable ecosystems project in Yunnan Province, People's Republic of China. Yunnan's Provincial Government has initiated a major programme to develop and further utilise its biological resources to help improve economic conditions for its citizens. They are co-operating with the US Geological Survey (USGS) on evaluation and management of biological resources so economic development will be compatible with sustainable ecological systems. Scientists from the USGS and co-operating universities will provide expertise on synthesising biological data, conducting a Gap Analysis for the Province, evaluating innovative economic opportunities, and designing an effective education, training, and outreach programme. 相似文献
823.
The intent of this paper is to operationalize some aspects of local sustainability in a suitable development scenario and to compare its energy-use and environmental impacts to trend development. After a discussion of suburban sprawl, local sustainability, and the current state of the Pennypack Creek Watershed in the Philadelphia metro region, these residential location scenarios are presented. The latter were created using geographic information systems software and are based on projections from the Delaware Valley Regional Planning Commission. The impacts of the scenarios on energy use, air emissions, greenhouse gas emissions, water quality, and biological integrity were estimated with very few data, and the effect on the value of generic ecosystem services was assessed. The suitable development scenario was 29% better in terms of energy use and air and greenhouse gas emissions, 2.4% worse on water quality, and 2.6% better with respect to biological integrity. Given its net beneficial results, recommendations for policies to engender suitable development are made, and an outline of an implementation plan is proposed. Thoughts regarding refinements of the present work and the applicability of the methods used here to other watersheds conclude the work. 相似文献
824.
To mitigate the adverse environmental impact of forest roads, especially degradation of endangered salmonid habitat, many public and private land managers in the western United States are actively decommissioning roads where practical and affordable. Road decommissioning is associated with reduced long-term environmental impact. When decommissioning a road, it may be possible to recover some aggregate (crushed rock) from the road surface. Aggregate is used on many low volume forest roads to reduce wheel stresses transferred to the subgrade, reduce erosion, reduce maintenance costs, and improve driver comfort. Previous studies have demonstrated the potential for aggregate to be recovered and used elsewhere on the road network, at a reduced cost compared to purchasing aggregate from a quarry. This article investigates the potential for aggregate recycling to provide an economic incentive to decommission additional roads by reducing transport distance and aggregate procurement costs for other actively used roads. Decommissioning additional roads may, in turn, result in improved aquatic habitat. We present real-world examples of aggregate recycling and discuss the advantages of doing so. Further, we present mixed integer formulations to determine optimal levels of aggregate recycling under economic and environmental objectives. Tested on an example road network, incorporation of aggregate recycling demonstrates substantial cost-savings relative to a baseline scenario without recycling, increasing the likelihood of road decommissioning and reduced habitat degradation. We find that aggregate recycling can result in up to 24% in cost savings (economic objective) and up to 890% in additional length of roads decommissioned (environmental objective). 相似文献
825.
The peroxynitrite/porphyrin biomimetic system was established to investigate the effects of peroxynitrite on benzo[a]pyrene (B[a]P) metabolism. Through the comparison of three model systems consisting of different iron porphyrins, we found that the peroxynitrite/T(p-Cl)PPFeCl system showed the highest catalytic efficiency in the metabolism of B[a]P. We analyzed the B[a]P metabolites produced from this system by RP-HPLC method and firstly identified the formation of nitrobenzo[a]pyrenes which are the special metabolites of B[a]P induced by peroxynitrite. 相似文献
826.
Recently, Wu et al. (J Environ Sci 18(2006) 1167-1175) published a paper entitled as above. In the paper, the authors proposed a plotting method for describing adsorption isotherm, where adsorption density (q e) was plotted against the ratio of equilibrium concentration/particle concentration (Ce/W0) rather than (Ce) as traditionally defined. The authors claimed that this plot can eliminate the "particle concentration effect" (i.e., adsorption isotherm declines with increasing particle concentration), which may otherwise be inevasible with traditionally defined adsorption isotherms. We think that their conclusion is conceptually flawed and the plot may cause substantial inconstancy problems in practice. 相似文献
827.
以隐患排查治理相关制度建立与修订,隐患排查频次及方法,企业员工培训教育,隐患治理设备物资台账,隐患治理跟踪记录等17项指标调研数据为基础,根据数理统计的相关方法,对调研数据进行统计分析。结果表明:港、台资企业、外资企业、国有企业和中外合资企业在隐患排查治理相关制度修订和隐患治理落实方面仍有欠缺;私营企业在隐患排查治理方面相对薄弱,具体表现在相关制度编制不合理、不规范,隐患排查治理培训教育和物资投入不足,隐患治理记录台账缺失。根据调研中发现的问题提出建立隐患排查治理信息系统的方法,利用网络信息技术对企业隐患排查治理情况进行跟踪记录,增强政府部门对企业监管,提高企业隐患治理效率。 相似文献
828.
Irina Herzon Kaisa J. Raatikainen Aveliina Helm Solvita Rsia Slvi Wehn Ove Eriksson 《Ambio》2022,51(8):1753
We propose to consider semi-natural habitats—hotspots for biodiversity—being caught in a socio-ecological extinction vortex, similar to the phenomenon described for species threatened with extinction. These habitats are essentially socioecological systems, in which socioeconomic drivers are interlinked with ecological processes. We identify four highly interlinked and mutually reinforcing socio-economic processes, pertaining to the importance of semi-natural habitats for (i) agricultural production, (ii) policy, research and development; (iii) vocational education in the fields of agricultural sciences and (iv) public’s experiences with semi-natural habitats. Evidence from six countries in the boreal region demonstrates that recent slowing down or even reversal of two processes are insufficient to stop the extinction vortex phenomenon. We suggest research directions to ascertain the phenomenon, monitor its development and develop proactive actions to weaken the vortex. It is highly plausible that interventions directed at most, if not all, of the key vortex processes are needed to reverse the overall deteriorating trends of a socio-ecological system. 相似文献
829.
Frederick Willem Bouckaert Yongping Wei James Pittock Vitor Vasconcelos Ray Ison 《Ambio》2022,51(8):1871
Successful river basin governance is challenged by actor engagement in the various stages of planning and management. A governance approach for determining priorities for actors for sustainable management was developed, based on a river basin diagnostic framework consisting of four social-institutional and four biophysical indicators. It was applied in river basins in Australia, Brazil, China and France. Actors diagnosed current and target capacity for these indicators, and estimated synergistic influences of interacting indicators. The results reveal different priorities and transformative pathways to achieve basin plan outcomes, specific to each basin and actor groups. Priorities include biodiversity for the Murray-Darling, local water management needs for the São Francisco and Yellow rivers, and improved decision-making for the Adour-Garonne. This novel approach challenges entrenched views about key issues and actor engagement roles in co-implementation of the basin plan under existing prevailing governance models, with implications for engagement and international collaboration on basin governance.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01699-4. 相似文献
830.