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111.
The province of Huelva in the SW of Spain presents high environmental contrasts: together with the great abundance of natural spaces, it shows the impacts of historical natural resources exploitation processes. In the Ria of Huelva, the effluents of the chemical industries must be added to the contaminating inputs of the Tinto and Odiel rivers, coming from the acid drainage of the mines located in the Iberian Pyrite Belt. This forced the Environmental Agency (AMA) to elaborate in 1987 an Effluent Remediation Plan in order to negate unacceptable environmental impacts. The application of a grey box systemic analysis to the AMD pollution, undergone by the Tinto and Odiel rivers has allowed to set a conclusive explanation of the sampling results observed for a period of 11 years, thus making available an overall view of the polluting process and, above all, an explanation of its partial aspects. 相似文献
112.
Selecting Socio-Economic Metrics for Watershed Management 总被引:1,自引:0,他引:1
The selection of social and economic metrics to document baseline conditions and analyze the dynamic relationships between
ecosystems and human communities are important decisions for scientists, managers, and watershed citizens. A large variety
of social and economic data is available but these have limited use without theoretical frameworks. In this paper, several
frameworks for reviewing social-ecosystem relations are offered, namely social sanctions, sense of place, civic structure,
and cultural differences. Underlying all of these frameworks are attitudes, beliefs, values, and norms that affect which questions
are asked and which indicators are chosen. Much work and significant challenges remain in developing a standard set of spatially
based socio-economic metrics for watershed management. 相似文献
113.
Visuthismajarni P Vitayavirasuk B Leeraphante N Kietpawpan M 《Environmental monitoring and assessment》2005,104(1-3):409-418
The potential ecological risks associated with contaminants from 15 abandoned shrimp ponds in southern Thailand were assessed at the screening level. Shrimp ponds reported as out of production for more than 2 years were selected as sampling sites. The assessment endpoint was identified as the protection of aquatic life from hazard of multiple agents or stressors in water or sediment from the ponds. The measurement endpoints were amount of toxic phytoplankton species, Yellow Head Viruses, SEMB viruses, oxytetracycline, cadmium, copper, and manganese. Data from field measurements and laboratory analyses obtained primarily from April to June 2003 were used in the risk analysis. The results showed that insignificant amounts of stressors were present, except for the metals. So, only concentration values of the metals were used in the calculation of hazard quotients (HQ) for risk characterization. The highest potential ecological risk characterized by the highest HQ value observed for each metal was 19 for manganese, 4.3 for cadmium, and 1.8 for copper. These findings indicated a need for further ecological risk assessment at a more detailed level to focus on the bioavailability and effects of metals from abandoned shrimp farms, with manganese the highest priority. 相似文献
114.
A simple, sensitive, convenient and low cost spectrofluorometric technique for determination of quinalphos is described. Quinalphos is decomposed with sodium ethoxide. Resultant sodium diethyl thiophosphate (Na-DETP) is extracted with a cationic fluorescein as ion pair complex into 1-chloro-2-nitrobenzene. The fluorescence of the ion pair, fluorescein-DETP is measured at 530 nm after excitation at 490 nm. This technique is applicable for the determination of quinalphos in water, food grains and vegetable samples up to ng level with Amberlite XAD-4. 相似文献
115.
Wiersma YF 《Environmental monitoring and assessment》2005,100(1-3):1-9
Environmental benchmarks are widely used in Canadian environmental assessment as a standard against which to monitor air or water quality in response to human activities in the environment. Recent work in Canada has developed the concept of ecological benchmarks as a complement to environmental benchmarks. However, implementation of ecological benchmarks may be challenging. This paper presents an analogy between ecological benchmarks and the more commonly used environmental benchmarks, as an attempt to increase understanding and use of ecological benchmarks in resource management, assessment, and monitoring. Ecological benchmarks, and their corresponding indicators, will be challenging to identify and use. However, through the use of the principles of adaptive management, effective ecological indicators and benchmarks can be established. Although it is essential that ecological benchmarks are site-specific, the analogy and general principles outlined here are applicable to assessment and monitoring in any part of the world. 相似文献
116.
乌鲁木齐市汽车尾气排污现状及防治对策探讨 总被引:1,自引:0,他引:1
对乌鲁木齐市在用车辆进行了路抽检调查,通过大量数据分析,得出乌鲁木齐市目前汽车尾气排放情况仍令人担忧,治理工作不容忽视。 相似文献
117.
118.
A ten year summary of concurrent ambient water column and sediment toxicity tests in the Chesapeake Bay watershed: 1990-1999 总被引:1,自引:0,他引:1
The goal of this study was to identify the relative toxicity ofambient areas in the Chesapeake Bay watershed by using a suiteof concurrent water column and sediment toxicity tests at seventy-five ambient stations in 20 Chesapeake Bay rivers from1990 through 1999. Spatial and temporal variability was examinedat selected locations throughout the 10 yr study. Inorganicand organic contaminants were evaluated in ambient water andsediment concurrently with water column and sediment tests toassess possible causes of toxicity although absolute causalitycan not be established. Multivariate statistical analysis wasused to develop a multiple endpoint toxicity index (TOX-INDEX) at each station for both water column and sediment toxicity data. Water column tests from the 10 yr testing period showed that49% of the time, some degree of toxicity was reported. The mosttoxic sites based on water column results were located inurbanized areas such as the Anacostia River, Elizabeth River andthe Middle River. Water quality criteria for copper, lead,mercury, nickel and zinc were exceeded at one or more of thesesites. Water column toxicity was also reported in localizedareas of the South and Chester Rivers. Both spatial and temporalvariability was reported from the suite of water column toxicitytests. Some degree of sediment toxicity was reported from 62% of the tests conducted during the ten year period. The ElizabethRiver and Baltimore Harbor stations were reported as the most toxic areas based on sediment results.Sediment toxicity guidelines were exceeded for one or more of thefollowing metals at these two locations: arsenic, cadmium,chromium, copper, lead, nickel and zinc. At the Elizabeth Riverstations nine of sixteen semi-volatile organics and two of sevenpesticides measured exceeded the ER-M values in 1990. Ambientsediment toxicity tests in the Elizabeth River in 1996 showedreduced toxicity. Various semi-volatile organics exceeded the ER-M values at a number of Baltimore Harbor sites; pyrene anddibenzo(a,h)anthracene were particularly high at one of thestations (Northwest Harbor). Localized sediment toxicity was alsoreported in the Chester, James, Magothy, Rappahannock, andPotomac Rivers but the link with contaminants was not determined.Both spatial and temporal variability was less for sedimenttoxicity data when compared with water column toxicity data. Acomparison of water column and sediment toxicity data for thevarious stations over the 10 yr study showed that approximatelyhalf the time agreement occurred (either both suite of testsshowed toxicity or neither suite of tests showed toxicity). 相似文献
119.
MARTIN A. STAPANIAN STEVEN P. CLINE DAVID L. CASSELL 《Environmental monitoring and assessment》1997,45(3):237-257
We evaluate a field method for determining species richness andcanopy cover of vascular plants for the Forest Health MonitoringProgram (FHM), an ecological survey of U.S. forests. Measurementsare taken within 12 1-m2 quadrats on 1/15 ha plots in FHM.Species richness and cover are determined for four height classes(strata) within each quadrat and aggregated by stratum over the entireplot. We estimated (1) the agreement between experienced trainers andinexperienced technicians who collected the data on this survey(accuracy) and (2) the agreement among the technicians (precision) forresults on species richness and cover from 3 test plots at 3 timeintervals. The methods appear to be highly precise, although somediscrepancies with the values obtained by the trainers were found.Trainers found significantly more species in the ground stratum (0–0.6 m) and measured significantly more cover in the uppermost stratum(>4.9 m). The proportion of variation due to measurement error andtemporal variability was less than 13% for species richness (all strata)and cover (all but one stratum). This indicates that the method issuitable for monitoring changes in species richness and canopy coverfor a large-scale synoptic monitoring project such as FHM. 相似文献
120.
Marco Ferretti 《Environmental monitoring and assessment》1997,48(1):45-72
Part of this paper has been prepared for the lecture Forest Health Assessment-Criteria,Methods and Problems given by the author at the UIMPuniversity course Sanidad Forestal en el Bosques Mediterraneos yTemplados. Implicacion de la Contaminacion Atmosferica y del Cambio Global, held in Valencia, Spain, October, 1995. Assessment and monitoring of forest health representsa key point for environmental policy and for the management ofenvironmental resources. With the renewed interest in assessment andmonitoring of forest health generated by the suspected occurrence ofa widespread forest decline in Europe and North America, manyactivities have been undertaken: however, some questions should beconsidered and clarified when attempting to estimate forest health.Particularly, the objective(s) of the assessment and monitoringprogram should be carefully identified. Identification of a program‘stask has a number of implications and consequences: it implies adefinition of what concept of forest health (forest ecosystem health,forest health or forest trees health?) is assumed, what will be thetarget entity to be monitored, and therefore the identification of therelevant assessment questions and assessment endpoints.Consequences concern the definition of the spatial scale (frominternational to landscape and plot scale monitoring) and ecologicalcoverage (from single species population to population ofecosystems) of the program, which can have a considerable influenceon the choice of the proper sampling strategy and tactic, as well ason the most suitable methods, indicators and indices to be used.Although much of the work in the field of forest health and airpollution has concentrated on surveys on crown transparency anddiscoloration, there is an entire range of methods, indicators andindices developed to assess the health status of forests. The decisionas to which ones should be used will depend on the aim of theprogram and on economic and practical considerations. A furtherconsideration concerns the time span of the program, but anydecision in this field is subject to many limitations due to difficultiesin predicting future monitoring needs. All these points should becarefully considered and implemented according to a rigorousQuality Assurance procedure since any decision will influence futurework for many years. 相似文献