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Gold mining is the principal polluting activity in themunicipality of Poconé at the northern limit ofthe Pantanal of Mato Grosso, Brasil and ischaracterized by the inadequate use of mercury in thegold extraction process. A way to contribute to theassessment of the environmental impact of mercuryrelease in the Pantanal is to make use of bioaccumulation. Thus, determinations of total mercuryin 188 Gastropods of three different species were madein seven different sampling sites during the dry andwet periods. Increase of mercury levels in the snailswas restricted to the gold mining area and adjacentsedimentation areas. The largest mercuryconcentrations were found at the Tanque dos Padressite, reaching 2.04 g g-1 in individuals ofPomacea scalaris. In the other sampling sites,molluscs collected in the Araras/Piuval Bay complex,a mercury retention area, showed the largest mercuryconcentration, reaching up to 1.12 g g-1.  相似文献   
2.
通过比较生物指示与生物监测技术和仪器分析技术的分析过程及原理,结合北京市土壤中土壤脲酶与土壤重金属含量之间的相关关系的案例,及生物指示与生物监测技术在水生生态系统及大气污染研究中的应用状况,系统阐述了生物指示与生物监测技术研究的发展历程、研究前沿及发展方向.指出定量校正及不同学科与地区的科学团队的合作是生物指示与生物监测技术研究中需要克服的关键问题,并提出生物指示与生物监测技术研究的目标是整合不同学科的研究方向,为人类健康与环境安全的保护与预测提供技术支持.  相似文献   
3.
The presence of tropospheric ozone was monitored by estimating necrotic flecks on the leaves of the ozone-sensitive tobacco variety Bel W3 in Estonia in 1990 and 1991. The indicator and control plants (variety Samsun) were planted in four localities (Käsmu, northern Estonia; Tartu, central Estonia, with two sites and Kooraste, southern Estonia). The percentage of the leaf area covered with necrotic flecks (necrotic index of the leaf) was determined individually for each leaf from mid-June until the end of September. The mean daily increment of the necrotic index for the period between two observations (typically 6–14 days) was calculated for each plant (NIIplant) and for the site (NIIsite). The latter parameter indicates the variability of ozone episodes during the vegatation period. Ozone damage to leaves displayed an irregular pattern throughout the vegetation period, the values of NIIsite ranging from 0 to 0.3 (Kooraste, 1990) and 0.9 to 2.8 (Käsmu, 1991). The average NIIsite for the vegetation period was highest in northern Estonia (0.77 in 1990 and 1.47 in 1991) and lowest in southern Estonia (0.07 in 1990). High ozone damage in Käsmu can be explained by the close location (70–80 km) of the experimental site to major thermal power plants of Estonia and cities (Tallinn and Helsinki). Higher ozone damage in all the observed sites in 1991 as compared to 1990 can be accounted for different conditions for ozone formation.The number of sunny hours was 27% higher in 1991. In July the difference in sunny hours was almost twofold. It is concluded that ozone damage to plants is likely to occur in sunny summers in Estonia.  相似文献   
4.
This investigation analyses whether soil nematode diversity is correlated with soil functional parameters to serve as bioindicator of soil functioning. The analysis focuses on the interrelations of nematofauna, microflora, and soil nitrogen pools. The sites studied represent six major European grassland types: Northern tundra, atlantic heath, wet grassland, seminatural temperate grassland, East European steppe, and mediterranean garigue. Continental and local climate gradients were combined to a wide and continuous range of microclimate conditions. Nematode richness, as indicated by the number of genera, was highest under temperate conditions and declined towards the climatic extremes. Differences in richness affected all nematode feeding types proportionally. Nematode richness was the only parameter among a range of 15 alternatives tested that exhibited consistent correlations with mass and activity parameters of both nematofauna and microflora in the mineral grassland soils (garigue, wet grassland, seminatural grassland, steppe). In the same soils, the nematode Maturity Index was the best indicator of nitrogen status. We conclude that a high nematode richness can generally be seen as a good indicator of an active nematofauna and microflora in mineral grassland soils, and hence as an indicator of the decomposition function. The prospects of exploiting nematode diversity as an indicator of soil functioning are critically discussed.  相似文献   
5.
Anthropogenic landscape changes in Central Europe occurred in several stages. Characteristic features include an acceleration in the sequence of changes, a continual increase in the scope and complexity of ecologic problems, growing destabilization of the natural household and a rising proportion of irreversible changes.Various bioindication techniques are excellently suited for detecting and evaluating landscape changes, as reflected in a large number of case studies. Of these, a number are classified by the authors according to the following criteria: landscape features/components, structure of the test area, and time framework for the studies.Thorough changes must be brought about in man's relation with nature to remedy the aggrevated environmental situation, with these priorities: making human thinking and action compatible with the environment, transforming material production along ecological lines, and applying ecological principles to landscape management, for example in the form of landscape planning.  相似文献   
6.
In order to identify the potential of sulfur (S) content in the rings of Masson pine (Pinus massoniana) in the Pearl River Delta as a bio-indicator of regional history of atmospheric pollution, dendrochemistry was used to determine the temporal distribution of S content in the xylem of Masson pines from Zhaoqing Dinghushan and Nanhai Xiqiaoshan, Guangdong Province, southern China. The results indicated that contents of xylem S increased temporally and peaked in the rings formed in the most recent years at both sites. In the rings formed during the same period before the 1980s, S contents were not significantly different between the two sites, while in the rings formed at the same period after the 1980s, S content at Xiqiaoshan were significantly higher than those at Dinghushan. The chronosequences of the S indices at both sites could be easily marked as three periods: before 1970, during 1971–1985, and during 1986–2002. Based on the temporal changes of the xylem S contents and certain social-economic indices after the 1980s in the Delta, the history of atmospheric pollution at the study sites could be reconstructed as follows: 1) before 1970, a period in which the air was relatively clear, 2) 1971–1985, a period in which the air was gradually polluted, and 3) 1986–2002, a period in which the air was most severely polluted in the Delta. __________ Translated from Journal of Beijing Forestry University, 2008, 30(2): 1–7 [译自: 北京林业大学学报]  相似文献   
7.
节肢动物生物指示研究综述   总被引:2,自引:0,他引:2  
从生物指示的概念和首要目标,指示生物的定义、类别和功能,生物指示研究的步骤,指示生物和环境变量之间关系的可预测性及定量化,以及指示值方法,综述了节肢动物作为指示生物研究概况,列举了常见的节肢动物指示类群及其指示目标,剖析了当前生物指示研究中存在的问题,指出了在科学方法论基础上多学科合作进行多个类群生物指示研究,建立较完善的生物指示系统,服务于地区土地管理、生态建设及生物多样性保护等,将成为生物指示研究的发展趋势和主要方向。  相似文献   
8.
A study was made of oribatid mite communities and their responses to metal contamination derived from the Kosogorsky metallurgical plant located in the Tula District, Russia. Mite communities were sampled in three different seasons in four sites at different distances from the smelter. Concentrations of zinc, copper, cadmium, lead and iron were measured in ten mite species. The data show that the mite community as a whole is quite tolerant to the metal contamination caused by the Kosogorsky plant. At the polluted sites some species typical for nutrient-rich soils appeared, but community structure and species diversity were not seriously affected by metal contamination. In general, oribatid mites accumulated metals to very high internal concentrations. Average Cu, Cd, Pb and Fe concentrations did not differ significantly between species, but Zn did, and its level was associated with the mode of feeding of the species. Microphytophagous species, feeding exclusively on fungi, accumulated zinc in higher concentrations than other mites. This study illustrates the potential for bioindication by the little studied but species-rich group of soil oribatids.  相似文献   
9.
Long-term investigations on Collembola in Russian forests revealed that both stable and fluctuating communities can exist in natural ecosystems. Stable collembolan communities are characteristic of mesic moisture conditions, whilst fluctuating communities are typical of either xeric or hygric habitats. Stable communities are determined by between-year constancy in species and ecological structures, though other characteristics (for instance, total collembolan abundance or number of species) can vary. Stability of collembolan communities is externally stimulated by the constancy of environmental conditions or by their cyclic changing. Stable collembolan communities are best suited for the bioindication of long-term anthropogenic impacts on natural ecosystems, whereas fluctuating communities better reflect short-term environmental changes. A temporal predictability is possible only for stable communities.  相似文献   
10.
为探讨珠江三角洲马尾松年轮S含量作为生物指标追踪区域大气污染历史变迁的意义,该文通过树木年轮化学分析方法,研究了肇庆鼎湖山和南海西樵山马尾松木质部S含量的时间变化规律。结果表明,两地马尾松木质部S平均含量随时间的增长呈明显上升趋势,在最晚形成的木质部中S含量最高;在20世纪80年代以前,两地相同时期的马尾松木质部S含量差异不显著,80年代后,西樵山马尾松木质部S含量显著高于同期鼎湖山马尾松木质部S含量;从两地马尾松木质部S最终年表发现,木质部S含量存在着1970年前、1971—1985年和1986—2002年3个明显区别的时段;基于两地马尾松木质部中S含量时间变化规律,结合珠江三角洲20世纪80年代以后的某些特定经济指标分析,恢复了研究地大气污染历史:1941—1970年为大气相对清洁期;1971—1985年为大气污染开始出现并持续增强期;1986—2002年为大气污染最严重期。   相似文献   
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