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1.
Pollution and parasitism in the aquatic environment   总被引:2,自引:0,他引:2  
The studies of aquatic parasitology and of aquatic pollution effects both have experienced increasing interest during the recent fifteen years. Although considerable effort has been spent on studying the role of pollution as a cause or a trigger of anomalies, tumors and infectious diseases in aquatic organisms, the interactions between pollution and parasitism have been largely neglected by scientists.Pollution and other man-made alterations of the aquatic environment may affect a parasite community directly by acting on free-living parasite stages or on ectoparasites, or indirectly by acting on the intermediate or the definitive host population. Certain pollution conditions favour the propagation of parasites by excluding their natural predators, by reducing the resistance of their hosts or by providing improved living conditions for their intermediate hosts. In a number of experimental studies parasitized organisms have been shown to suffer from greater mortalities when exposed to high temperature, to low oxygen stress or to high levels of dissolved heavy metal salts, when compared to nonparasitized control animals. Unfortunately, field studies on synergistic effects of pollution and parasites on host populations are still scarce and seldom offer more than qualitative observations and theoretical evaluations.The complexity of the pollution-parasite-host system complicates the use of parasites as indicators of pollution effects. However, experience from aquaculture practice teaches that a number of (mostly ecto-) parasites are more susceptible to certain chemicals (used as parasiticides) and to artificial alterations of salinity, temperature or oxygen content of the water than their hosts. Accordingly, it is postulated that during future studies the composition of ectoparasitic faunas of aquatic organisms might turn out to become a useful and quickly reacting indicator for effects of certain pollution conditions, such as anthropogene oxygen deficiency, salt introduction from salines into freshwater ecosystems, and introduction of certain heavy metal salts.  相似文献   

2.
Noise pollution is a novel, widespread environmental force that has recently been shown to alter the behaviour and distribution of birds and other vertebrates, yet whether noise has cumulative, community-level consequences by changing critical ecological services is unknown. Herein, we examined the effects of noise pollution on pollination and seed dispersal and seedling establishment within a study system that isolated the effects of noise from confounding stimuli common to human-altered landscapes. Using observations, vegetation surveys and pollen transfer and seed removal experiments, we found that effects of noise pollution can reverberate through communities by disrupting or enhancing these ecological services. Specifically, noise pollution indirectly increased artificial flower pollination by hummingbirds, but altered the community of animals that prey upon and disperse Pinus edulis seeds, potentially explaining reduced P. edulis seedling recruitment in noisy areas. Despite evidence that some ecological services, such as pollination, may benefit indirectly owing to noise, declines in seedling recruitment for key-dominant species such as P. edulis may have dramatic long-term effects on ecosystem structure and diversity. Because the extent of noise pollution is growing, this study emphasizes that investigators should evaluate the ecological consequences of noise alongside other human-induced environmental changes that are reshaping human-altered landscapes worldwide.  相似文献   

3.
While many studies in the medical literature documented causal relationships between air pollution and negative health outcomes immediately following exposure, much less is known about the long run health consequences of pollution exposure. Using the 1997 Indonesian forest fires as a natural experiment, we estimate the long term effects of air pollution on health outcomes. We take advantage of the longitudinal nature of the Indonesia Family Life Survey (IFLS), which collects detailed individual data on a multitude of health outcomes, in both 1997 and 2007. We find significant negative effects of pollution, which persist in the long run. Men and the elderly are impacted the most, while children seem to recover almost completely from these early shocks. For the entire population, an extra standard deviation in the pollution level increases the likelihood of a poor general health status by almost 3%.  相似文献   

4.
Marine pollution has been studied under the following groupings of effects; harm to living resources, hazards to human health, reduction of amenities and interference with other users of the sea. This paper is concerned mainly with the first two categories and their interrelation. Apart from certain seabirds affected by oil, the major stocks of marine animals show no evidence of reduction by pollution. Pollution effects are generally insignificant in relation to other factors governing reproductive success, survival, growth and population size. Even in the North Sea, which has received a greatly increased pollution load during the last three decades, both total production of fish and catch per unit of effort (a measure of abundance) of cod, haddock and plaice increased during the 20 years 1950--69. Very recent decreases have been due to over-exploitation but, except in certain estuaries and immediate coastal waters, direct damage by pollution to marine populations and ecosystems is not evident. Pollution effects can, however, be detected by chemical analysis. The paper examines human health risks arising in the marine environment, particularly from contaminated seafood, especially in relation to sewage pollution, metals such as mercury, cadmium and lead, synthetic organic substances and oil.  相似文献   

5.
Gray  John S. 《Hydrobiologia》1989,188(1):397-402
With some notable exceptions, such as the echinoderm and oyster larvae tests, the species traditionally used in bioassays are not sufficiently sensitive to detect subtle ecological effects of pollutants. It is suggested that by using ecological criteria, species can be identified from any pollution gradient that are sensitive to subtle effects of pollution. Examples are given using gradients of oil, sewage and titanium dioxide pollution, showing how ecologically sensitive species for use in laboratory bioassays can be selected objectively.Many marine molluscs show microgrowth bands, which can be used as in situ field bioassays. An example is given using the bivalve Cerastoderma edule.  相似文献   

6.
Duncan Lee  Gavin Shaddick 《Biometrics》2010,66(4):1238-1246
Summary In studies that estimate the short‐term effects of air pollution on health, daily measurements of pollution concentrations are often available from a number of monitoring locations within the study area. However, the health data are typically only available in the form of daily counts for the entire area, meaning that a corresponding single daily measure of pollution is required. The standard approach is to average the observed measurements at the monitoring locations, and use this in a log‐linear health model. However, as the pollution surface is spatially variable this simple summary is unlikely to be an accurate estimate of the average pollution concentration across the region, which may lead to bias in the resulting health effects. In this article, we propose an alternative approach that jointly models the pollution concentrations and their relationship with the health data using a Bayesian spatio‐temporal model. We compare this approach with the simple spatial average using a simulation study, by investigating the impact of spatial variation, monitor placement, and measurement error in the pollution data. An epidemiological study from Greater London is then presented, which estimates the relationship between respiratory mortality and four different pollutants.  相似文献   

7.
Epidemiological evidence has concurred with clinical and experimental evidence to correlate current levels of ambient air pollution, both indoors and outdoors, with respiratory effects. In this respect, the use of specific epidemiological methods has been crucial. Common outdoor pollutants are particulate matter, nitrogen dioxide, carbon monoxide, volatile organic compounds and ozone. Short-term effects of outdoor air pollution include changes in lung function, respiratory symptoms and mortality due to respiratory causes. Increase in the use of health care resources has also been associated with short-term effects of air pollution. Long-term effects of cumulated exposure to urban air pollution include lung growth impairment, chronic obstructive pulmonary disease (COPD), lung cancer, and probably the development of asthma and allergies. Lung cancer and COPD have been related to a shorter life expectancy. Common indoor pollutants are environmental tobacco smoke, particulate matter, nitrogen dioxide, carbon monoxide, volatile organic compounds and biological allergens. Concentrations of these pollutants can be many times higher indoors than outdoors. Indoor air pollution may increase the risk of irritation phenomena, allergic sensitisation, acute and chronic respiratory disorders and lung function impairment. Recent conservative estimates have shown that 1.5-2 million deaths per year worldwide could be attributed to indoor air pollution. Further epidemiological research is necessary to better evaluate the respiratory health effects of air pollution and to implement protective programmes for public health.  相似文献   

8.
Pollution-induced changes in populations.   总被引:5,自引:0,他引:5  
The effects of pollution by organic matter, oil or industrial waste on marine communities are remarkably similar. Diversity values fall, biomass and numbers of organisms initially rise and then fall as the pollution load is increased. Diversity indices are, however, insensitive to pollution-induced changes and have to be assessed subjectively. Departure from a log-normal distribution of individuals among species offers a sensitive and objective method of assessing perturbation effects on communities. Under severe pollution stress, the dominant species are those which have a flexible life-history ranging from direct development to a planktonic larva and the ability to undergo short-term genetic selection. Species have a somewhat less flexible life-history strategy show increased abundance under conditions of slight pollution. The increase in abundance of seven or eight neither rare nor common species, which gives the departure from a log-normal distribution, is suggested as being the most significant and the earliest detectable change caused by pollution in a community. Thus the presence of a species in a polluted area may be more a question of life-history strategy than the tolerance of adverse environmental conditions. If this hypothesis is correct, considerable doubt must beplaced on the ecological relevance of data from toxicity tests.  相似文献   

9.
吴锋  曾麟岚  刘桂君 《生态学报》2022,42(8):3045-3055
农业面源污染因其分散性、滞后性和不确定性而成为环境治理的难点。面源污染物迁移转化过程的模拟模型发展迅速,而农业面源污染管理政策仿真评估模型研究相对较为滞后。系统梳理与分析了自上而下宏观目标约束、自下而上微观行为传导及宏观与微观上下耦合三类政策仿真模型研究进展,总结了当前模型的基础理论与方法的优势与不足。本文提出了融合流域水系统过程规律认知,构建宏观政策目标自上而下约束与微观主体行为自下而上传导耦合的农业面源污染政策仿真模型,实现政策仿真模拟在国家、区域、流域与栅格跨尺度上的嵌套传导、参数互验与系统预测,以解决因农业面源污染防治主体的多元性与防治对象的广泛性特征所导致的复杂性系统难题,使得政策效应模拟仿真结果空间显性化,进而实现农业面源污染控制的政策管理由粗放型向精准化方向迈进。  相似文献   

10.
Community air pollution is the new airborne disease of our generation''s communities. It is caused by the increasing use of fuel, associated with both affluence and careless waste. Photochemical air pollution of the California type involves newly defined atmospheric reactions, is due mostly to motor vehicle exhaust, is oxidizing, and produces ozone, plant damage, impairment of visibility and eye and respiratory symptoms.Aggravation of asthma, impairment of lung function among persons with chronic respiratory disease and a possible causal role, along with cigarette smoking in emphysema and chronic bronchitis, are some of the effects of photochemical pollution.More subtle effects of pollution include impairment of oxygen transport by the blood due to carbon monoxide and interference with porphyrin metabolism due to lead. Carbon monoxide exposures may affect survival of patients who are in hospitals because of myocardial infarction.While many uncertainties in pollution-health reactions need to be resolved, a large number of people in California have health impairment due to airborne disease of this new type.  相似文献   

11.
Increasing artificial illumination during night has multifaceted effects on species. Moths are shown to be distracted and attracted by artificial light sources, leading to increased mortality through predation or exhaustion. Increased mortality can be expected to increase selection pressure on morphology, particularly those being functional in light detection and flight ability. We were thus interested if intraspecific traits differ between areas and times with differing light pollution values. We chose the moth Agrotis exclamationis, a common species in the Berlin-Brandenburg region, Germany, a region that offers very different levels of light pollution across space and time. We examined body length, eye size and forewing length, traits likely targeted through selection due to light pollution. We examined moths collected over the past 137 years. We predicted decreasing forewing length, body and eye size, in response to increasing light pollution and expected to see trait changes from the past to today, and from rural to urban areas, representing temporal and spatial gradients of increasing light pollution. In order to determine current levels of light pollution, we used radiance values of the years 2012 to 2019. These values were the base to extrapolate previous radiance values for all sample sites and years. We observed no trait differences along the spatial gradient, but trait and sex dependant changes along the temporal gradient. We could not confirm a direct causal link between changes in body size and female eye size. However, we revealed indirect effects of light pollution, and assume habitat fragmentation and host-plants to be the main drivers for these effects. A trend towards smaller-eyed females in ‘medium’ and ‘high’ light-polluted areas over time could be a first indication that morphological trait changes to light pollution are taking place.  相似文献   

12.
Understanding the pollution sensitivity of lichens   总被引:3,自引:0,他引:3  
RICHARDSON, D. H. S. 1988. Understanding the pollution sensitivity of lichens. Lichens have been widely used to monitor air quality in urban and industrial situations. This review summarizes the effects of the various components of air pollution including metals, sulphur dioxide and acid rain. The mechanisms leading to the accumulation of elements by lichens or induction of damage by air pollutants are discussed.  相似文献   

13.
Flexible multilevel models are proposed to allow for cluster-specific smooth estimation of growth curves in a mixed-effects modeling format that includes subject-specific random effects on the growth parameters. Attention is then focused on models that examine between-cluster comparisons of the effects of an ecologic covariate of interest (e.g. air pollution) on nonlinear functionals of growth curves (e.g. maximum rate of growth). A Gibbs sampling approach is used to get posterior mean estimates of nonlinear functionals along with their uncertainty estimates. A second-stage ecologic random-effects model is used to examine the association between a covariate of interest (e.g. air pollution) and the nonlinear functionals. A unified estimation procedure is presented along with its computational and theoretical details. The models are motivated by, and illustrated with, lung function and air pollution data from the Southern California Children's Health Study.  相似文献   

14.
尘污染对植物的生理和生态特性影响   总被引:1,自引:0,他引:1  
王宏炜  曹琼辉  黄峰  袁琳 《广西植物》2009,29(5):621-626
综述了尘污染对植物和植物群落的生理和生态作用和影响,并初步探讨了其原因和机制。尘污染能影响植物的光合作用、呼吸作用和蒸腾作用,并携带有毒性污染物穿透进入植物组织。尘污染会导致植物发生可见的伤害症状,引起生产力的下降。大部分的植物群落也会受到尘的影响而改变群落结构。今后要加强对自然条件下尘对植物影响的深入研究和植物不同种类间对尘敏感性的差异的研究。  相似文献   

15.
Previous studies of the efficiency of Chinese electricity industry have been limited in providing insights regarding policy implications of inherent trade‐offs of economic and environmental outcomes. This study proposes a modified data envelopment analysis method combined with materials balance principle to estimate ecological and cost efficiency in the Chinese electricity industry. The economic cost and ecological impact of energy input reallocation strategies for improving efficiency are identified. The possible impacts of pollution taxes upon the levels of sulfur dioxide (SO2) emissions are assessed. Estimation results show that (1) both energy input costs and SO2 could be reduced through increasing technical efficiency. (2) It is possible to adjust energy input mix to attain ecological efficiency, and, correspondingly, SO2 would be reduced by 15%. (3) The Chinese electricity industry would reduce its unit cost by 9% if optimal ecological efficiency is attained and reduce its unit pollution by 13% if optimal cost efficiency is attained, implying that there are positive ecological synergy effects associated with energy cost savings and positive economic synergy effects associated with SO2 pollution reductions. (4) Estimated shadow costs of SO2 reduction are very high, suggesting that, in the short term, the Chinese electricity industry should pursue cost efficiency instead of ecological efficiency, since alternative abatement activities are less costly and some of the abatement cost could be further offset by energy input cost savings. (5) There would be no significant difference between the impacts of pollution discharge fees and pollution taxes on SO2 emissions levels because of the relatively low pollution tax rate.  相似文献   

16.
Light pollution is a global disturbance with resounding impacts on a wide variety of organisms, but our understanding of these impacts is restricted to relatively few higher vertebrate species. We tested the direct effects of light pollution on herbivore performance as well as indirect effects mediated by host plant quality. We found that artificial light from streetlights alters plant toughness. Additionally, we found evidence of both direct and indirect effects of light pollution on the performance of an herbivorous insect, which indicates that streetlights can have cascading impacts on multiple trophic levels. Our novel findings suggest that light pollution can alter plant-insect interactions and thus may have important community-wide consequences.  相似文献   

17.
W. D. Oliff 《Hydrobiologia》1960,16(2):137-196
Summary A survey of pollution in the Bushmans river, and a tributary, the Little Bushmans river in the vicinity of Estcourt, Natal, is described. The pollution arose mainly from wastes discharged from a boardmill, a milk-processing factory, and a sewage-disposal, irrigation farm. The effects of these effluents on the chemistry of the river waters, and on the biological communities in them is described.The communities at polluted stations have been classified in relation to the degree of pollution, and the equivalence of the classification with the systems described by other workers has been indicated. Differences observed between communities in normal and polluted stretches of the rivers are suggested as indices of pollution.  相似文献   

18.
Plastic pollution is distributed across the globe, but compared with marine environments, there is only rudimentary understanding of the distribution and effects of plastics in other ecosystems. Here, we review the transport and effects of plastics across terrestrial, freshwater and marine environments. We focus on hydrological catchments as well‐defined landscape units that provide an integrating scale at which plastic pollution can be investigated and managed. Diverse processes are responsible for the observed ubiquity of plastic pollution, but sources, fluxes and sinks in river catchments are poorly quantified. Early indications are that rivers are hotspots of plastic pollution, supporting some of the highest recorded concentrations. River systems are also likely pivotal conduits for plastic transport among the terrestrial, floodplain, riparian, benthic and transitional ecosystems with which they connect. Although ecological effects of micro‐ and nanoplastics might arise through a variety of physical and chemical mechanisms, consensus and understanding of their nature, severity and scale are restricted. Furthermore, while individual‐level effects are often graphically represented in public media, knowledge of the extent and severity of the impacts of plastic at population, community and ecosystem levels is limited. Given the potential social, ecological and economic consequences, we call for more comprehensive investigations of plastic pollution in ecosystems to guide effective management action and risk assessment. This is reliant on (a) expanding research to quantify sources, sinks, fluxes and fates of plastics in catchments and transitional waters both independently as a major transport routes to marine ecosystems, (b) improving environmentally relevant dose–response relationships for different organisms and effect pathways, (c) scaling up from studies on individual organisms to populations and ecosystems, where individual effects are shown to cause harm and; (d) improving biomonitoring through developing ecologically relevant metrics based on contemporary plastic research.  相似文献   

19.
空气污染作为一种有害的环境因素,对人类及动物的生理、心理均有影响.在鸟类中,信鸽(Columba livia)是研究空气污染影响的理想模型.为探究空气污染的行为学效应,通过收集并筛选2018和2019年成都市信鸽协会春秋两个季节举办的64场赛事共285羽参赛5场及以上的信鸽不同空距等级下的归巢速度,利用混合线性模型分析...  相似文献   

20.
In integrating ecotoxicology and marine mammalogy two principal themes are conceivable: (1) the impact of contaminants on marine mammals and (2) the feasibility of monitoring marine pollution with marine mammals. Monitoring should be an alert procedure, carried out with a sensitive sensor. Uncertainties in interpreting analyses and the low susceptibility of marine mammals to short-term changes in pollution, make them inappropriate for pollution monitoring at present. To answer the question whether pollutants affect marine mammals, the occurrence of contaminants and the response of the animals to those chemicals have to be assessed. In studying the occurrence of contaminants it is essential that atmospheric and riverine input, geochemical processes, and processes involved with the occurrence of natural compounds are considered. To investigate the mechanisms by which pollutants affect physiological processes the kinetics of contaminants in the animals and their clinical toxicity effects have to be studied. Comparative reference data on physical and chemical blood parameters facilitates checking for hematological disorders, electrolyte imbalance, serum biochemistry and hormonal changes. Following such a concept the retrospective study of pollution effects on marine mammals might be turned into a predictive approach.  相似文献   

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