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1.
The effect of air pollution from nitrogen dioxide (NO2) on the epiphytic lichens of the city of Seville (Spain) has been studied. Indices of air purity (IAP) were calculated, based on the lichen flora ofMelia azedarach L. present at 25 stations distributed through the city. The arrangement and classification of the stations by principal component analysis and cluster analysis, respectively, enabled the study area to be zoned into four zones of air purity. Accordingly, the zonal map of air purity for the city of Seville yields a gradient of air purity that is very steep from the centre to the outskirts. The dependence of 77.6% of IAP variability with NO2 pollution levels detected with air emission sensors distributed through the city suggests the relationship between NO2 levels and zones of air purity.  相似文献   

2.
The geographic distributions of two common species of epiphytic lichens,Phaeophyscia limbata (Poelt) Kashiw. andLecanora pulverulenta Müll. Arg., on city park trees in the Osaka Plain and their relation to the distribution of SO2 and NO2 was examined. The concentrations of SO2 and NO2 are greater in the central area of this plain, and decrease with distance from the center. The frequency ofL. pulverulenta is lowest in the central area, and increases gradually toward the periphery. In contrast, the frequency ofP. limbata is highest in the intermediate area, and lower in the central and peripheral areas, i.e. at intermediate SO2 and NO2 concentrations. We conclude thatL. pulverulenta is more useful thanP. limbata as a bioindicator of air pollutants such as SO2 and NO2.  相似文献   

3.
Aim To investigate the general pattern of changes in species richness and diversity of vascular plants due to environmental contamination and associated habitat changes imposed by point polluters, and identify the sources of variation in the response of plant communities to industrial pollution. Location Global. Methods We collected species richness and diversity data from 86 studies that were conducted around 60 atmospheric point polluters worldwide and reported in 95 papers (published in 1953–2007). We used meta‐analysis to search for a general effect and to compare between polluter types and plant groups, and linear regression to describe the latitudinal gradient and to quantify relationships between pollution and effect size. Results Although the species richness of vascular plants generally decreased with pollution, the effects were not uniform across the studies. Polluters that cause soil acidification imposed a stronger detrimental effect on plant diversity than industries whose emissions increased soil pH. An overall adverse effect was primarily due to the contribution of non‐ferrous smelters and aluminium plants; the effects of other SO2‐emitting industries were less detrimental, albeit negative, and the effects of chemical plants, fertilizer factories and cement industries did not differ from zero. Longevity of the pollution impact only made a slight contribution to the detected variation, while adverse effects increased with increase in pollution load. Main conclusions This study is the first demonstration of geographical variation in the responses of plant communities to aerial emissions: adverse effects increased from high to low latitudes, and this pattern was explained primarily by increases in both the diversity of original (undisturbed) communities and mean summer temperatures. The latter result suggests that under a future warmer climate the existing pollution loads may become more harmful. Model calculations indicate that a detectable depauperation of plant communities is unlikely if the polluter emits < 1500 t of SO2 annually.  相似文献   

4.
The present study was driven by the wish to broaden the selection of ecological indicators for estimating the alkaline dust pollution. The abundance of the algal species Trentepohlia umbrina was studied on Pinus sylvestris trunks, an acidic substrate that it normally does not occupy. The study was carried out in northern Estonia in the surroundings of four major limestone quarries, considerable local-level sources of dust pollution. The cover of T. umbrina on tree trunks was clearly higher near the quarries, evidently due to the elevated bark pH, its maximum values reaching ca. 30% (mean of five trees studied per sample plot). The cover of the species decreased steeply at the distance of 800–900 m from the quarries; further than 1000 m from the quarries the maximum cover was already less than 4%, and further than 2000 m less than 1%. The correlation between the cover of T. umbrina and measured bark pH values indicated a steep increase in cover at about pH 3.8–3.9; the cover values varied between 0 and 4% below and between 10 and 31% above that pH. These results confirm that T. umbrina could be used as an indicator species of alkaline dust pollution. The species forms reddish powdery coating on tree trunks, and in case of high abundance can be very conspicuous looking, being easily detectable at field.  相似文献   

5.
Habitat suitability estimates derived from species distribution models (SDMs) are increasingly used to guide management of threatened species. Poorly estimating species’ ranges can lead to underestimation of threatened status, undervaluing of remaining habitat and misdirection of conservation funding. We aimed to evaluate the utility of a SDM, similar to the models used to inform government regulation of habitat in our study region, in estimating the contemporary distribution of a threatened and declining species. We developed a presence‐only SDM for the endangered New Holland Mouse (Pseudomys novaehollandiae) across Victoria, Australia. We conducted extensive camera trap surveys across model‐predicted and expert‐selected areas to generate an independent data set for use in evaluating the model, determining confidence in absence data from non‐detection sites with occupancy and detectability modelling. We assessed the predictive capacity of the model at thresholds based on (1) sum of sensitivity and specificity (SSS), and (2) the lowest presence threshold (LPT; i.e. the lowest non‐zero model‐predicted habitat suitability value at which we detected the species). We detected P. novaehollandiae at 40 of 472 surveyed sites, with strong support for the species’ probable absence from non‐detection sites. Based on our post hoc optimised SSS threshold of the SDM, 25% of our detection sites were falsely predicted as non‐suitable habitat and 75% of sites predicted as suitable habitat did not contain the species at the time of our survey. One occupied site had a model‐predicted suitability value of zero, and at the LPT, 88% of sites predicted as suitable habitat did not contain the species at the time of our survey. Our findings demonstrate that application of generic SDMs in both regulatory and investment contexts should be tempered by considering their limitations and currency. Further, we recommend engaging species experts in the extrapolation and application of SDM outputs.  相似文献   

6.
Benthic invertebrates were collected from a subarctic lake during 1976 to assess the effectiveness of diversity indices and indicator species as measures of heavy metal pollution. Collections were made near an operating metal mine, where sediments were contaminated with high levels of arsenic (up to 2,500 mg/kg dry weight), mercury (500 µg/kg), lead (850 mg/kg), copper (750 mg/kg) and zinc (950 mg/kg). A total of 25 species and a diversity index of 2.4—2.9 were recorded in this heavily impacted area. Chironomids (Procladius denticulatus, Heterotrissocladius changi, Chironomus decorus) were most common in the sediments, followed in importance by molluscs (Pisidium casertanum) and oligochaetes (Lumbriculus variegatus). There were 23 and 25 species in the areas of moderate and negligible contamination, respectively. The diversity indices ranged from 2.4–2.6 and 2.4–2.8 and the main species were generally similar to those found in the heavily impacted area. While diversity indices and indicator species were therefore ineffective in monitoring metal contamination, the strong negative correlation between the concentration of metals and the abundance of benthic organisms provided a much more realistic assessment of the level of contamination.  相似文献   

7.
In order to assess the impact of SO2, CO2, NO x , and CO on non-enzymatic foliar defense mechanism around oil refineries, the present study was undertaken in Batman, Turkey during the periods February–April–June 2002. For this purpose, the four common evergreen plants at all sites, Pinus nigra Arn. subsp. pallasiana (Lamb.) Halmboe, Ligustrum vulgare L., Thuja orientalis L., and Nerium oleander L. were selected as test plants. Four study sites were selected at the Batman Refinery area (AR). Four control sites were also selected at a distance of about 5 km from the refinery (OR). Responses to oil refinery pollution of plants, heavy metals, chlorophyll (chl), proline, carotenoids, lipid peroxidation, SH-compounds, and ascorbic acid were measured. In addition, ambient pollutant gas concentrations were measured. The pollutant gas concentrations were high in the immediate vicinity of oil refinery. The levels of total chl, SH-compounds, ascorbic acid, and chla/chlb ratio were found to decrease, and the amount of proline, carotenoids, lipid peroxidation, and reduced ascorbate/oxidized ascorbate ratio were found to increase in comparison to plants growing at the control sites. A comparison of four evergreen plant species indicated that L. vulgare was the most resistance to refinery induced air pollution and the magnitude of foliar injury symptoms was greatest in P. nigra and T. orientalis.  相似文献   

8.
Aquatic oligochaetes are abundant in polluted areas and are, therefore, commonly used as bioindicators to study organic pollution in rivers and streams. In order to develop a species-level oligochaete biotic index to reflect the River Pollution Index (RPI) in the Taichung Water Basin in Taiwan, we conducted a systematic sampling scheme to collect aquatic oligochaetes from the sediment samples of watercourses in the Taichung Water Basin, Taiwan. We evaluated the relationships between aquatic oligochaetes and the sewage pollution using statistical methods. The distribution of aquatic oligochaetes in relation to environmental variables, such as water quality and sediment characteristics of the regional urban contaminated streams was expressed by Canonical Correspondence Analysis (CCA). We identified 17 species of aquatic oligochaetes (Annelida, Clitellata) including 3 species of Tubificidae, 13 species of Naididae, and 1 species of Enchytraeidae from the watercourses of an urban region in the Taichung Water Basin in Taiwan, during the summer and winter of 2005 and 2006. A positive correlation was found between the total abundance of aquatic oligochaetes and the RPI (r = 0.58, P < 0.05). However, only population density of the most abundant tubificid, Limnodrilus hoffmeisteri, increased with increasing RPI values and a significantly negative correlation was found between the population density of the naidid, Nais communis, and RPI values. The results of CCA indicated that certain naidids, such as Aulophorus furcatus and Allonais gwaliorensis also tolerated extremely polluted environments in upper stream or stony habitats, implying that tubificids should not be the sole representation of simple biotic indices but should also include pollution-tolerant naidids. We found that the community structure of aquatic oligochaetes was influenced by short-term variations in microhabitat rather than according to seasonal factors in our study region. The results proved that aquatic oligochaetes were sensitive enough to provide a supplement for the regional urban pollution assessment applications for biotic indicators at the species-level.  相似文献   

9.
Krystyna Prejs 《Hydrobiologia》1986,131(3):281-286
Tissue damage, seen as differently coloured necrotic patches on rhizomes of three Potamogeton species, was found to result from nematode feeding.A high density of plant-feeding Hirschmanniella gracilis was found in the underground parts of Potamogeton pectinatus.The abundance and composition of the nematode aggregations seem to be related to the morphology of Potamogeton rhizomes.  相似文献   

10.
中国淡水原生动物多样性及其所受威胁   总被引:5,自引:0,他引:5  
概述了地球上原生动物多样性现状,指出它在生物学界中的地位及其对人类的作用。从生态学概念出发,把淡水原生动物作为一个集合类群,对其多样性和所受威胁进行了讨论。以武汉东湖为例,讨论了半个世纪来由于人类活动的影响引起湖泊富营养化后,原生动物丰度增长了10倍,优势种出现替代现象,并有明显的小型化倾向。以长江三峡地区为例,分析了工业污染能损伤70%原生动物种类。原生动物多样性指数变化表明:在有机污染影响下作为饮用水的汉江其水质已达临界边缘。对待开发的西南武陵山地区生物资源考察中,用原生动物多样性现状阐明该地区水生态系的稳定性。  相似文献   

11.
Melanic forms of the peppered moth Biston betularia were well established in The Netherlands by the end of the 19th century, indeed the first records of the black carbonaria form in 1867 are only about 20 years later than in England. Analysis of extensive sampling data collected by B. J. Lempke for a period of several years beginning in 1969 shows that carbonaria was at a frequency of about 60 to 70% in most of the country where epiphyte communities on trees were reduced due to the effects of air pollution. The pale typica and the three intermediate insularia forms were each at similar, low frequencies. Only in the extreme north and south-east of The Netherlands where epiphyte floras were richer was carbonaria at a lower frequency of less than 40%. Samples collected from seven localities in 1988 show that carbonaria has dramatically declined to a frequency of less than 10%. In contrast to England, the fully black form is being replaced not only by typica but also by the darkest of the insularia phenotypes. The decline in melanism coincides with a period of decreasing levels of sulphur dioxide and of increasing species diversity of lichens on trees.  相似文献   

12.
Chlor-alkali plants are known to be major sources of Hg emissions into the air. Therefore level of this metal in their surrounding must be carefully controlled. The aim of this work was to study the impact of the chlor-alkali industry in Brzeg Dolny (SW Poland) on the length of the vegetative short shoots of the pollution tolerant Betula pendula using the concentrations of Cd, Co, Cr, Cu, Fe, Hg, Mn, Ni, Pb and Zn in the ubiquitous, terrestrial moss Brachythecium rutabulum as the pollution indicator of the environment. This investigation showed up to 14 mg kg−1 elevated concentrations of Hg in mosses from sites the most close (0–500 m) to the chlor-alkali factory. This concentration decreased with increasing distance from the factory. Two and half km away from the factory the Hg concentration falls to values of 0.1–0.2 mg kg−1 being still higher than background concentrations of 0.03–0.04 mg kg−1. Decreasing concentrations of Co, Cr, Fe and Ni were also correlated with increasing distance from the plant. The results indicate that B. rutabulum may be a suitable ecological indicator of metal pollution by chlor-alkali industry. Higher concentration of accumulated metals by this moss corresponds with longer vegetative short shoots of B. pendula. Vegetative short shoots may be used as bioindicators of metal pollution where mosses are absent. This study demonstrates the importance of controlling the emissions of chlor-alkali industry especially if situated in the midst of densely populated areas with potential risks to the inhabitants.  相似文献   

13.
The release of anthropogenic pollution into freshwater ecosystems has largely transformed biodiversity and its geographical distribution patterns globally. However, for many communities including ecologically crucial ones such as zooplankton, it is largely unknown how different communities respond to environmental pollution. Collectively, dispersal and species sorting are two competing processes in determining the structure and geographical distribution of zooplankton communities in running water ecosystems such as rivers. At fine geographical scales, dispersal is usually considered as the dominant factor; however, the relative role of species sorting has not been evaluated well, mainly because significant environmental gradients rarely exist along continuously flowing rivers. The Chaobai River in northern China represents a rare system, where a significant environmental gradient exists at fine scales. Here, we employed high‐throughput sequencing to characterize complex zooplankton communities collected from the Chaobai River, and tested the relative roles of dispersal and species sorting in determining zooplankton community structure along the pollution gradient. Our results showed distinct patterns of zooplankton communities along the environmental gradient, and chemical pollutant‐related factors such as total phosphorus and chlorophyll‐a were identified as the major drivers for the observed patterns. Further partial redundancy analyses showed that species sorting overrode the effect of dispersal to shape local zooplankton community structure. Thus, our results reject the dispersal hypothesis and support the concept that species sorting caused by local pollution can largely determine the zooplankton community structure when significant environmental gradients exist at fine geographical scales in highly polluted running water ecosystems.  相似文献   

14.
提出了随时间变化的人类活动效应对物种多样性影响的多物种竞争非自治动力模式,并以洪湖为例模拟了湿地水鸟物种多样性对人类活动效应(生境持续毁坏)的响应过程。模拟发现:对于强.强物种,生境的持续破坏使得湿地水鸟的物种多度大幅度减小,并发生优势种群的更替;对于弱-弱物种,将导致大批的弱物种种群迅速灭绝,而余下的弱物种种群将做准周期振荡;尽管停止对湿地生境的持续毁坏,仍会使一批弱物种种群继续走向灭绝,并且使得原来最强的几个种群最终灭绝。物种灭绝对生境毁坏的这种时间滞后性,即破碎的生境中存在着一些“活死者”,必须引起自然保护学家的关注,否则会低估了实际处于灭绝边缘的物种的数目,从而影响正确的物种保护决策的制订。  相似文献   

15.
16.
Estimating and predicting temporal trends in species richness is of general importance, but notably difficult because detection probabilities of species are imperfect and many datasets were collected in an opportunistic manner. We need to improve our capabilities to assess richness trends using datasets collected in unstandardized procedures with potential collection bias. Two methods are proposed and applied to estimate richness change, which both incorporate models for sampling effects and detection probability: (a) nonlinear species accumulation curves with an error variance model and (b) Pradel capture–recapture models. The methods are used to assess nationwide temporal trends (1945–2018) in the species richness of wild bees in the Netherlands. Previously, a decelerating decline in wild bee species richness was inferred for part of this dataset. Among the species accumulation curves, those with nonconstant changes in species richness are preferred. However, when analyzing data subsets, constant changes became selected for non‐Bombus bees (for samples in collections) and bumblebees (for spatial grid cells sampled in three periods). Smaller richness declines are predicted for non‐Bombus bees than bumblebees. However, when relative losses are calculated from confidence intervals limits, they overlap and touch zero loss. Capture–recapture analysis applied to species encounter histories infers a constant colonization rate per year and constant local species survival for bumblebees and other bees. This approach predicts a 6% reduction in non‐Bombus species richness from 1945 to 2018 and a significant 19% reduction for bumblebees. Statistical modeling to detect species richness time trends should be systematically complemented with model checking and simulations to interpret the results. Data inspection, assessing model selection bias, and comparisons of trends in data subsets were essential model checking strategies in this analysis. Opportunistic data will not satisfy the assumptions of most models and this should be kept in mind throughout.  相似文献   

17.
Zoological gardens host large numbers of wild species and domestic forms, mostly not indigenous to the place where the zoological garden is located. Escapes (or releases) from zoological gardens are recognized as a pathway of introduction of alien species, leading in some cases to a naturalized population. Although previously reported worldwide, scientific accounts of escapes from zoos are rare and often anecdotal. In this note, we document, for the first time in Europe and, to our knowledge, in an area outside its native range, a case of introduction and establishment of a feral population of Llama (Lama glama), originating from a group of animals living in captivity at the Zoological Park of Cavriglia (Tuscany, central Italy). We reconstruct in detail the story of the population since 1974, also reporting preliminary data on abundance, distribution and diet. Finally, we critically evaluate the causes of this introduction, highlighting how unsafe the management of a zoological garden can be, and we discuss the implications for conservation and management perspectives.  相似文献   

18.
Declines are a distinctive category of tree disease, complex to define and quantify and challenging to mitigate due to their multiple causes and heterogeneous tree response patterns. In many parts of Europe oak decline syndromes are severely impacting tree health and having a measurable economic impact on forestry. In the UK the impact of periodic oak declines is expanding against a backdrop of multiple environmental pressures, to levels capable of threatening the UK’s native oak woodland. Here we explore the growth histories of oak trees at a site symptomatic of Chronic Oak Decline (COD), in the South of England; Speculation Cannop in the Forest of Dean, Gloucestershire. The dendrochronological picture at the site reveals that trees with current external COD symptoms have shown suppressed growth, in relation to the regional average, from early on in their lives. Moreover, there is an amplified reduction in minimum ring width in Symptomatic trees as compared to a healthy subsample of Control trees, likely to be heavily dominated by reduced latewood width in affected trees, as decline sets in. Broadly, the site reveals the initial appearance of decline, roughly 40 years after planting, in 1860. There is considerable variability in the later decline history pattern in Symptomatic trees but there are clusters of decline episodes in the 1920s, 1960s, 1980s and 1990s at this site. The Control trees are not always unaffected but rather show growth releases after each historical decline phase. The trees that currently show external decline symptoms do not have a history of these growth releases. We conclude that investigating the tree ring growth histories at sites impacted by COD could provide an important management tool, and ring width histories of trees at affected sites should be used in the identification of the decline predisposing factors, that a management strategy requires.  相似文献   

19.
After years of efforts to avoid or reduce the impact of infrastructure projects on nature, the principle of ecological compensation has been incorporated in Dutch governmental policy. Ecological compensation aims to recover those ecological functions and natural values that still remain affected after maximum effort has been made to reduce the impact of the intervention (mitigation). The accepted aim of current policy is thus no-net-loss of area and quality by means of mitigative and compensatory measures. As part of the planning process for construction of a stretch of road in The Netherlands, viz., the A50 road link in the province of North Brabant, a Nature Compensation Plan (NCP) was required to be drawn up. This work has recently been completed by the Regional Directorate of Public Works and Water Management, the initiator of the intervention. The NCP, initially presented as a Draft Plan, was drawn up by the Regional Directorate using a preliminary method designed by the Centre of Environmental Science of Leiden University for deriving compensatory measures. After an opportunity for public comment, the Draft Plan was revised to form a Final NCP. This article describes, firstly, the preliminary method for deriving ecological compensatory measures. The method starts by quantifying the effects of habitat loss, habitat disturbance (by changes in noise emissions, in the water table and in outdoor recreational patterns), barrier action and fauna casualties. Following mitigation of impacts on nature, compensation for non-mitigable effects focuses successively on area size, derived from the impacts on breeding birds, and on area quality, derived from the habitat requirements of the vegetation and fauna groups affected by the road. Guidelines for identifying appropriate locations for compensation are also formulated. Secondly, the compensation method is applied to calculate the mitigative and compensatory measures for the A50 trajectory between Eindhoven and Oss. Thirdly, two comparisons are made: the Draft NCP is compared with the results of the preliminary method, and the Draft and the Final NCP are compared with one another in order to identify the role of the interest groups that played a major role in commenting on the Draft Plan. Finally, realization of the compensatory measures and development of the preliminary method itself are discussed. On the basis of the experience with the A50 case study, a more robust compensation method for road projects is to be developed.  相似文献   

20.
赵淑清  方精云  雷光春 《生态学报》2001,21(7):1171-1179
全球面临着生境破碎化的危机,物种保护已成为人类面临的重大课题,并不是所有的人对岛屿生物地理学理论的产生及其关注的海洋岛屿都很熟悉,但是越来越多生物赖以生存的自然栖息地的丧失和破碎化都是有目共睹的,岛屿生物地理学和集合种群理论是目前物种保护的两个基本理论,物种迁入率和绝灭率的动态变化决策岛屿上的物种丰富度是岛屿生物地理学理论的核心内容,而集合种群理论关注的是局部种群之间个体迁移的动态以及物种的续存条件,在概述两个理论形成、发展及其核心内容的基础上,着重比较它们的异同点以及在生态学理论和实践中的应用,并论述物种保护理论范式从岛屿生物地理学向集合种群理论转变的基本背景和原因。  相似文献   

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