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851.
福建漳州菜园土壤重金属污染评价及防治 总被引:9,自引:0,他引:9
调查福建省漳州市菜园土壤重金属Cd、Pb、Hg、Cr及非金属有害元素As含量,并采用单项污染指数法和综合污染指数法进行评价。结果表明,以福建土壤背景值为评价标准,漳州市部分菜园土壤受到重金属污染,单项污染指数的顺序为Cd(2.39) >Hg(2.00) >Pb(1.40) >Cr(0.63) >As(0.57),污染元素主要为Cd、Pb、Hg,其中Cd、Hg为中度污染;综合污染指数为1.75,属轻度污染。而以土壤环境质量二级标准为评价标准,其综合污染指数为0.14,污染等级为未受污染。 相似文献
852.
为了解酸雨对温州三垟湿地水体氮营养盐数量的影响,本文测定了三垟湿地水体中不同形态氮的含量,其中氨氮2.90~10.75 mg·L-1,平均5.38 mg·L-1、硝态氮0.16~0.44 mg·L-1,平均0.31 mg ·L-1;总氮34.04~63.20 mg·L-1,平均55.75 mg·L-1和水体的pH值,6.1~6.5,平均6.4;并测算了近两年通过降水输入到三垟湿地和三垟湿地水体中不同形态氮的数量及其占湿地现有水体中各形态氮的比例,其中输入到三垟湿地氨氮、硝态氮和总氮的量分别为2.8~2.86× 10 kg、2.87×104~4.96×104kg和5.35×104~7.82×104 kg,分别占湿地水体现有量的56%~6%、11.21~19.38倍和12%~17%;直接输送到三垟湿地水体各形态氮的数量0.72×104~0.8×104 kg、0.83×104~1.44×104 kg和1.55×104~2.27×104,分别占现有量的16%~19%,3.24~5.63倍和3%~5%.结果表明,酸雨是三垟湿地水体氮污染的主要来源之一,对三垟湿地水体富营养化产生重要影响. 相似文献
853.
High-biodiversity landscapes around the globe are under immense pressure due to the expansion of human activities. To ensure effective monitoring and management of such landscapes, it is necessary to integrate landscape composition and the associated socio-economic processes in the conservation schemes. Artificial Night-Time Light (ANTL) pollution is a recent but striking environmental alteration due to human interventions. It is a major threat for species and communities which co-evolved with invariant natural light patterns over geological times. In spite of its potential key role in re-shaping natural systems, ANTL is seldom considered in macroecology. Remote sensing provides a unique set of tools to integrate ANTL in macroecological studies. In this work, we used remote sensing data of night-time lights along with Enhanced Vegetation Index (EVI) to study the effects and extent of ANTL in the night-time landscape (nightscape) of two protected areas in Italy. Our results showed that a considerable number of semi-natural vegetated patches suffer from ANTL pollution with varying magnitude. We observed a decline in highly suitable patches for biodiversity while the remaining patches were found concentrated in the innermost part of the parks. By simulating an exponential decrease in ANTL we showed that a moderate reduction in ANTL pollution would result in regaining a substantial amount of highly suitable patches for biodiversity. The decline in homogeneous dark patches in vegetated landscapes has negative impacts on biodiversity as well as on the ecosystem services it provides. Therefore, it is high time that the scientific community and the policy-makers increase their efforts to monitor and mitigate the ecological impacts of ANTL on ecosystems. The integration of light pollution in landscape ecology could combine remote sensing with other aspects of light pollution like indirect propagation and spectral composition. 相似文献
854.
THE INFLUENCE OF SO2 AND NO2 ON THE GROWTH, DEVELOPMENT AND GAS EXCHANGE OF BETULA PENDULA ROTH 总被引:5,自引:5,他引:0
P. H. FREER-SMITH 《The New phytologist》1985,99(3):417-430
855.
Christopher J. Palmer Michael B. Culley Peter N. Claridge 《Environmental Biology of Fishes》1979,4(1):71-75
Synopsis A further occurrence of Atherina boyeri in British waters is recorded. This species has a distribution which can be broadly defined as Mediterranean but has been occasionally recorded in waters which are beyond the northerly limits of its normal range. These records have usually been associated with localised thermal pollution but, at Oldbury-upon-Severn, England, this is probably not so. Morphometric and meristic data are presented which show clearly that this is a genuine record of A. boyeri. The existence of this species in waters with minimal, if any, thermal enrichment raises interesting questions regarding its distribution.This example and the other abnormal records of A. boyeri are, therefore, considered in relation to a number of environmental parameters. The parameters discussed, namely increased water temperature, decreased salinity and lagoon conditions have all been implicated in previous records.The conclusion tentatively reached is that A. boyeri is capable of surviving under a cooler temperature régime than that with which it is normally associated. Normally its range is restricted by inter-specific competition. In conditions of calmer water, however, in which there is also reduced salinity it is able to compete and maintain itself successfully. 相似文献
856.
The release of water from deep below the surface of large dams causes significant disturbance to water temperature regimes in downstream river channels with consequent impacts upon aquatic biota and river health. The Murray–Darling Basin (MDB) has a large number of dams, which are known to cause cold water pollution (CWP) in the downstream reaches of the impounded rivers. This study reviews the situation with regard to CWP in the MDB including the location, magnitude and extent of temperature suppression, the impacts upon fish, constraints and progress towards ameliorating the problem. 相似文献
857.
We studied the effects of aerial pollution on the expression of Delayed Inducible Resistance (DIR) against herbivores in the boreal willow Salix borealis , growing naturally around the nickel-copper smelter at Monchegorsk (NW Russia). In slightly polluted and clean sites, the manual defoliation (simulated insect herbivory) of willows resulted in the development of DIR, which was expressed in the post-treatment year as (i) a decrease in leaf damage, (ii) the dispersion of grazing damage within a plant, and (iii) a decrease in foliar quality, detected by the adverse effects on the larval relative growth rate of the autumnal moth, Epirrita autumnata . At the same time, in heavily and moderately polluted sites these effects were not observed, suggesting that DIR in plants growing under pollution impact was not expressed. Since DIR may be one of the important feedbacks regulating the population dynamics of herbivores, the disturbance of this feedback by pollution-induced environmental deterioration may contribute to the high densities of many herbivorous insects in polluted areas. 相似文献
858.
BackgroundWe investigated the concentrations of metals in fine particulate matter PM2.5 in the outdoor air around the home sites of 123 male children from Ahvaz, average age 7.56, along with their blood samples to measure pro-inflammatory responses (Immunoglobulin E and cytokines: IgE, IL-4 and IL-13).MethodsWe measured 6 metals (As, Cd, Cr, Hg, Ni and Pb) in three Ahvaz’s regions including industrial (Padad), vehicle traffic (Golestan) and control (Kianpars).ResultsThe higher concentrations of metals in the Padad as the industrial ambient air i.e., arsenic, cadmium, chromium, mercury and nickel coincided with the higher concentrations of those metals in exposed children (P < 0.05) versus the controls. Children in Golestan, the high traffic air pollution area had the highest lead concentrations (p < 0.05). Also a significant association was shown in Padad between blood arsenic and IgE (β = 26.59, P < 0.001), IL-4 (β = 172.1, P < 0.001) and IL-13 (β = 14.84, P < 0.001), blood chromium and IgE (β = 10.38, P < 0.001), IL-4 (β = 75.27, P < 0.001) and IL-13 (β = 5.27, P < 0.001) and blood mercury and IgE (β = 13.11, P < 0.001), IL-4 (β = 108.09, P < 0.001) and IL-13 (β = 7.96, P < 0.001) and blood lead and IgE(β = 0.92, P = 0.025), IL-4(β = 7.16, P < 0.001) and IL-13(β = 0.58, P = 0.003). However, no significant relation was found for Cadmium, Nickel in blood with IgE, IL-4 and IL-13 levels. Moreover, children from industrial areas showed significantly higher concentrations of IgE (mean = 146.44 pg/200landa, P < 0.001), IL-4 (mean = 548.23 pg/200landa, P < 0.001) and IL-13 (mean = 52.93 pg/200landa, P < 0.001) versus Golestan and Kianpars.ConclusionChildren residing in an industrial area with high concentrations of metals in PM2.5 had high metals in blood and high production of IgE, IL-4 and IL-13, reflecting an immune dysregulation and brisk inflammatory responses. 相似文献
859.
The Environmental Protection Department (EPD) of the Hong Kong Special Administrative Region Government (HKSARG) commissioned a consultancy study in 1999 to better understand the potential sources, fates, and existing pollution state of toxic substances in Hong Kong's marine environment. A desk-top survey and assessment was first performed on a comprehensive initial list of 556 toxic substances. A Preliminary Priority Toxic Substances List (PPTSL) of 135 chemicals was established, consisting of heavy metals, inorganic compounds, organo-metallic compounds, and trace organics. A territory-wide baseline field sampling and laboratory analysis exercise was then undertaken during 2001–2002 to determine the level of these PPTSL chemicals in the potential pollution sources (effluent discharges, stormwater discharges, air deposition) and the receiving marine environment (water, sediment, biota). A draft Priority Toxic Substances List (PTSL) was developed, taking into account chemicals detected in the local marine environment and those listed under the Stockholm Convention, the Rotterdam Convention, and the International Maritime Organization's Harmful Antifouling System Convention. The draft PTSL chemicals were subject to ecological and incremental human health risk assessments. Based on the risk assessment results, 17 Chemicals of Potential Concern (COPC) for Hong Kong's marine environment were identified, most of which were heavy metals in the sediment. The study findings suggest that Hong Kong's marine environment is not widely polluted with chemicals present at concentrations of toxicological concern. Although a number of potentially problematic pollutants (COPC) were identified, they are confined to a few “hot spots” and are unlikely to pose a territory-wide risk. Based on the study recommendations, the EPD initiated in 2004 a toxic substances monitoring program to keep the COPC in the marine environment under close surveillance. 相似文献
860.
This paper examines the long-term influence on pine (Pinus sylvestris L.) wood properties of alkaline dust pollution (pH 12.3–12.7) emitted over 135 years from a cement plant in Estonia. A study
of stemwood physical and mechanical properties in 70–80-year-old Scots pines growing in three zones of different air pollution
levels showed serious deviations in comparison with a relatively healthy forest in an unpolluted area. Specimens from polluted
trees evidenced smaller sapwood annual ring widths than those from the control trees. At the same time, the number of growth
rings in sapwood at breast height increased under pollution. In the polluted areas, percentage of latewood in the annual ring
widths was higher than in the unpolluted area. Small amounts of cement dust, which contains elements essential for the mineral
nutrition of the trees, might have acted as fertilizer. Pine wood in the polluted stands exhibited increased density, bending
strength across the grain, compression strength along the grain and, in some instances, hardness along the grain. 相似文献