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71.
Assessment of polycyclic aromatic hydrocarbon input to urban wetlands in relation to adjacent land use 总被引:2,自引:0,他引:2
The relationship between polycyclic aromatic hydrocarbons (PAHs) in wetland surface sediments and adjacent land use was assessed in the Elizabeth River, VA, an urbanized sub-estuary of the Chesapeake Bay. Significant differences (p<0.05) in surface sediment PAH concentration between sites indicated adjacent land use had a substantial influence on PAH concentration in wetland sediments. Wetlands adjacent to parking lots and petroleum industrial sites exhibited the highest PAH concentrations of all wetlands examined. Overall, commercial land uses had the highest PAH concentrations and automotive sources dominated (52-69%) PAH input to wetland surface sediments irrespective of adjacent land use. 相似文献
72.
鄂东南铁山地区土壤-植物系统中重金属元素分布及富集特征 总被引:2,自引:0,他引:2
采用原子荧光光谱法和等离子体质谱法(ICP-MS)对鄂东南铁山地区主要河流流经区土壤、植物中重金属元素质量分数及其富集特征的研究表明,研究区西港河流域下游局部地段形成Cu、Zn、Ni、Cd、As重金属元素的土壤污染,东港河流域下游局部地段形成Cd、Cu、As、Pb、Zn重金属元素的土壤污染,植物中已经形成Cd、Zn元素的超量富集.其中土壤中重金属元素的富集主要与冶炼厂废水和尾矿坝渗漏水有关,而植物中重金属元素的富集则受土壤中重金属元素质量分数和植物吸收性能的双重控制. 相似文献
73.
74.
Estuarine fish health assessment: evidence of wastewater impacts based on nitrogen isotopes and histopathology 总被引:2,自引:1,他引:1
Sewage effluent is a powerful agent of ecological change in estuaries. While the effects of sewage pollution on water quality are usually well documented, biological responses of exposed organisms are not. We quantified health impacts in the form of pathological tissue changes across multiple organs in estuarine fish exposed to elevated levels of treated wastewater. Structural pathologies were compared in wild populations of four fish species from two subtropical estuaries on the east coast of Australia that differ substantially in the amount of direct wastewater loadings. Uptake of sewage-derived nitrogen by fish was traced with stable nitrogen isotopes. Pathologies were common in the liver, spleen, gill, kidney and muscle tissues, and included granulomas, melanomacrophage aggregates, and multiple deformities of the gill epithelia. Tissue deformities were more frequent in fish exposed directly to wastewater discharges. Mullet (Valamugil georgii) were most affected, with only a single specimen free of pathologies in the sewage-impacted estuary. Similarly, in those fish that had structural abnormalities, more deformities were generally found in individuals from sites receiving sewage. These spatial contrasts in impaired fish health correspond to significantly enriched delta15N values in fish muscle as a consequence of fish assimilating sewage-N. Overall, the pattern of lower health and enriched delta15N values in fish from sewage-impacted areas suggests that organism health is lowered by sewage inputs to estuaries. Measurements of organism health are required to understand the effects of sewage on estuarine ecosystems, and histopathology of fishes is a powerful tool to achieve this. 相似文献
75.
76.
鄂东南矿山环境评价指标体系 总被引:8,自引:2,他引:6
在对鄂东南大型矿业基地的矿产资源开发现状、社会经济效益、矿业经济活动对生态环境影响及其存在的主要环境地质问题进行初步调查分析的基础上,确定了鄂东南矿山地质环境评价指标,以系统论及可持续发展理论建立了适合该区的矿山环境评价指标体系及具体的指标参数. 相似文献
77.
Herold M Román-Cuesta RM Mollicone D Hirata Y Van Laake P Asner GP Souza C Skutsch M Avitabile V Macdicken K 《Carbon balance and management》2011,6(1):13
Measuring forest degradation and related forest carbon stock changes is more challenging than measuring deforestation since
degradation implies changes in the structure of the forest and does not entail a change in land use, making it less easily
detectable through remote sensing. Although we anticipate the use of the IPCC guidance under the United Framework Convention
on Climate Change (UNFCCC), there is no one single method for monitoring forest degradation for the case of REDD+ policy.
In this review paper we highlight that the choice depends upon a number of factors including the type of degradation, available
historical data, capacities and resources, and the potentials and limitations of various measurement and monitoring approaches.
Current degradation rates can be measured through field data (i.e. multi-date national forest inventories and permanent sample
plot data, commercial forestry data sets, proxy data from domestic markets) and/or remote sensing data (i.e. direct mapping
of canopy and forest structural changes or indirect mapping through modelling approaches), with the combination of techniques
providing the best options. Developing countries frequently lack consistent historical field data for assessing past forest
degradation, and so must rely more on remote sensing approaches mixed with current field assessments of carbon stock changes.
Historical degradation estimates will have larger uncertainties as it will be difficult to determine their accuracy. However
improving monitoring capacities for systematic forest degradation estimates today will help reduce uncertainties even for
historical estimates. 相似文献
78.
79.
Darbra RM Ronza A Casal J Stojanovic TA Wooldridge C 《Marine pollution bulletin》2004,48(5-6):420-428
A methodology has been designed to assess the performance of the environmental management in sea ports. The Self Diagnosis Method, developed by two research teams and about sixty sea ports, allows the comparison of the current environmental situation with that corresponding to previous years and the assessment of the opportunities for improvement. The main objective is to review the management activities and procedures that affect the environment and the way the port authority handles significant environmental aspects. It has been designed as a "first level" tool: it can be applied in approximately six hours by a non-expert user. It is based on the ISO 14001 vocabulary, requirements and structure, and it can be considered as a first step in the voluntary implementation of an environmental management system for port communities. 相似文献
80.
Removal of ammonia toxicity in marine sediment TIEs: a comparison of Ulva lactuca,zeolite and aeration methods 总被引:5,自引:0,他引:5
Burgess RM Pelletier MC Ho KT Serbst JR Ryba SA Kuhn A Perron MM Raczelowski P Cantwell MG 《Marine pollution bulletin》2003,46(5):607-618
Toxicity Identification Evaluations (TIEs) can be used to determine the specific toxicant(s), including ammonia, causing toxicity observed in marine sediments. Two primary TIE manipulations are available for characterizing and identifying ammonia in marine sediments: Ulva lactuca addition and zeolite addition. In this study, we compared the efficacy of these methods to (1) remove NH(x) and NH(3) from overlying and interstitial waters and (2) reduce toxicity to the amphipod Ampelisca abdita and mysid Americamysis bahia using both spiked and environmentally contaminated sediments. The utility of aeration for removing NH(x) and NH(3) during a marine sediment TIE was also evaluated preliminarily. In general, the U. lactuca and zeolite addition methods performed similarly well at removing spiked NH(x) and NH(3) from overlying and interstitial waters compared to an unmanipulated sediment. Toxicity to the amphipod was reduced approximately the same by both methods. However, toxicity to the mysid was most effectively reduced by the U. lactuca addition indicating this method functions best with epibenthic species exposed to ammonia in the water column. Aeration removed NH(x) and NH(3) from seawater when the pH was adjusted to 10; however, very little ammonia was removed at ambient pHs ( approximately 8.0). This comparison demonstrates both U. lactuca and zeolite addition methods are effective TIE tools for reducing the concentrations and toxicity of ammonia in whole sediment toxicity tests. 相似文献