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2.
The results of censuses taken in 1995 to 2011 along two key routes in the areas of the Sulakskaya and Turalinskaya Lagoons, Dagestan (the western coast of the Middle Caspian Sea), are summarized. The state of the populations of regularly migrating birds and causes of long-term fluctuations in their abundance have been assessed by the method of long-term series of observations on trajectories of active migration along stationary routes. The results show that the abundance of 46 out of the 116 background taxa has decreased, while that of 70 taxa has increased or remained unchanged. The key regulatory factors include hydroclimatic conditions, anthropogenic impact, food supply, synurbanization, and weather. The results provide a basis for developing a unified strategy for the conservation of the birds of Eurasia. 相似文献
3.
Mining has become one of the main causes of increased heavy metal loading of river systems throughout the world. There is however an evident gap between assessments of soil contamination and metal release at the mined sites and estimates of river pollution. The present work focuses on Zaamar Goldfield, which is one of the largest placer gold mines in the world, located along the Tuul River, Mongolia, which ultimately drains into Lake Baikal, Russia. It combines field observations in the river basin with soil erosion modelling and aims at quantifying the contribution from natural erosion of metal-rich soil to observed increases in mass flows of metals along the Tuul River. Results show that the sediment delivery from the mining area to the Tuul River is considerably higher than the possible contribution from natural soil erosion. This is primarily due to excessive mining-related water use creating turbid wastewaters, disturbed filtering functions of deposition areas (natural sediment traps) close to the river and disturbances from infrastructures such as roads. Furthermore, relative to background levels, soils within Zaamar Goldfield contained elevated concentrations of As, Sr, Mn,V, Ni, Cu and Cr. The enhanced soil loss caused by mining-related activities can also explain observed, considerable increases in mass flows of metals in the Tuul River. The present example from Tuul River may provide useful new insights regarding the erosion and geomorphic evolution of mined areas, as well as the associated delivery of metals into stream networks. 相似文献
6.
Delta region of the Cauvery river in India is well known for paddy cultivation for centuries. Due to increased competition on river water sharing over the past century, availability and reliability of water in this region is dwindling. Changes in management practices, which caused the deterioration of traditional tank (relatively small reservoir) irrigation systems, and the difficulties in reviving them are discussed. Increasing the storage capacity of irrigation tanks for augmenting water availability for irrigation is discussed in detail. Managing the huge cost involved in deepening the heavily silted tanks in a sustainable manner is suggested through allowing mining activities in the tanks. Sample study on the suitability of soil for commercial uses indicates the possibility of mining in the tanks. 相似文献
7.
Historical operations at the Hanford Site (Washington State, USA) have released a wide array of non-radionuclide and radionuclide contaminants into the environment. As a result, there is a need to characterize contaminant effects on site biota. Within this framework, the main purpose of our study was to evaluate radionuclide concentrations in bird tissue, obtained from the Hanford Environmental Information System (HEIS). The database was sorted by avian group (water bird vs. upland bird), radionuclide (over 20 analytes), tissue (muscle, bone, liver), location (onsite vs. offsite), and time period (1971-1990 vs. 1991-2009). Onsite median concentrations in water birds were significantly higher (Bonferroni P < 0.05) than those in onsite upland birds for Cs-137 in muscle (1971-1990) and Sr-90 in bone (1991-2009), perhaps due to behavioral, habitat, or trophic species differences. Onsite median concentrations in water birds were higher (borderline significance with Bonferroni P = 0.05) than those in offsite birds for Cs-137 in muscle (1971-1990). Onsite median concentrations in the earlier time period were significantly higher (Bonferroni P < 0.05) than those in the later time period for Co-60, Cs-137, Eu-152, and Sr-90 in water bird muscle and for Cs-137 in upland bird muscle tissue. Median concentrations of Sr-90 in bone were significantly higher (Bonferroni P < 0.05) than those in muscle for both avian groups and both locations. Over the time period, 1971-2009, onsite median internal dose was estimated for each radionuclide in water bird and upland bird tissues. However, a meaningful dose comparison between bird groups was not possible, due to a dissimilar radionuclide inventory, mismatch of time periods for input radionuclides, and lack of an external dose estimate. Despite these limitations, our results contribute toward ongoing efforts to characterize ecological risk at the Hanford Site. 相似文献
8.
The results of landscape-ecological surveys in the Komsomolsk Nature Reserve (the Lower Amur region) have been used as a basis for empirical–statistical modeling of the spatial organization of floristic phratries and forest types that characterize the Amur sub-Pacific as part of the continental marginal part of the megaecotone. Trends in the evolutionary forest-forming processes are described. Mechanisms have been revealed for the origin of buffer forest communities, including spruce–broadleaf and nemoral fir–spruce forests of the Manchurian–Okhotian phratry. Forests of this phenomenal buffer flora are distinguished by extremely high parameters of structural and functional development and have reached the state approaching the evolutionary climax. The previously advanced concepts of the Pacific ecotone of Northern Eurasia as a focus of evolutionary processes in the continental biosphere have been confirmed. 相似文献
9.
Freshwater habitats are one of the planet’s most important, yet most manipulated, environments. This is what happens in Sarawak that the environment has been radically changed due to urban developments. This paper is promoting the idea that we do not need a complicated but a simple tool like fuzzy inference system to strike a balance between the existence of peat swamp and the humans who live nearer and nearer to it. Conditions vital to the survival and continuity of a natural wetland system can be adapted as fuzzy rules. These rules are capable of providing indicators of how much wetland can be exploited and at the same time still allow the system to properly functioning as a wetland. 相似文献
10.
The contents of heavy metals (HMs) were studied in freshwater hydrobionts from the south of the Russian Far East, including the area of wastewater discharge from a lead smelter (the village of Rudnaya Pristan, Primorye). The results showed that most invertebrates disappeared from the ecosystem as the toxicity of the aquatic environment increased. Mollusks of the genus Lymnaea proved to be most tolerant of HM pollution. As the contents of Pb, Mn, Cd, and Zn in bottom sediments increased, the amounts of these metals in mollusk bodies increased as well but to a much lesser extent, with the intensity of HM accumulation decreasing at their higher concentrations in the environment. The range of HM concentrations accumulated in the bodies of limneids noticeably broadened with an increase in technogenic impact. This is evidence for differences in the efficiency of mechanisms regulating the contents of trace elements in individuals of the same species under conditions of extreme pollution. 相似文献
11.
The aim of this work was to determine the 210Po content in marine birds which permanently or temporally live in the Polish part of the Baltic Sea. We chose 11 species of sea birds: three species permanently residing at southern Baltic Sea, four species of wintering birds and three species of migrating birds. The results show that the polonium is non-uniformly distributed in the marine birds. The highest activities of 210Po were observed in feathers, muscles and liver and the lowest in skin and skeleton. Species of birds that eat crustaceans, molluscs, fish and plants (long-tailed duck Clangula hyemalis, white-winged scoter Melanitta fusca) accumulated more polonium than species that eat mainly fish (great cormorant Phalacrocorax carbo, common guillemot Uria aalge) or plants (tufted duck Aythya fuligula). Moreover, about 63% of the 210Po that was located in feathers of razorbil (Alca torda) and long-tailed duck (C. hyemalis) was apparently adsorbed, suggesting an external source such as the air. It means that the adsorption of 210Po on the feather surface may be an important transfer from air to water. 相似文献
12.
India is the first country to introduce environmental legislation in the constitution but because of lengthy legal procedures,
it is very difficult to control environmental deterioration. There are many factors responsible for this deterioration. Coal
mining is one such activity where deterioration is very severe and the present communication aims this aspect. Coal is the
one of the most essential mineral having large reserves in India. It’s mining and beneficiation produce a variety of pollutants.
The main pollutants emitted during the processing of coal are green house gases, coal dust and acid mine drainage. Many reports
on different aspects of coal mining are available including reports on emission of different pollutants but the present work
is probably only of it’s kind in which the authors have tried to determine environment liability directly in terms of economy.
It was found that greenhouse liabilities, coal dust liability and sulphur liability are accounted for 12.07, 5.0 and 101.97
US$, making an overall 2.4% of the total economic gains due to coal mining. During the calculations approximate number of
total workers and other parameters have been taken into consideration. Who pays for this irreversible damage is a question.
Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue. 相似文献
13.
Patterns of seasonal and long-term dynamics of the size and structure of the bank vole population were studied in the European subtaiga subzone, the optimum of the species range. The dynamics of this population proved to undergo complex fluctuations with cyclic components, which have periods of one year and about three years. The one-year fluctuations of the population size and structure are accounted for by animal adaptation to seasonal changes in environmental factors. The fluctuations with the three-year quasi-period are determined by intrapopulation density-dependent mechanisms. 相似文献
14.
Abstract This paper discusses the basic concept and connotation of population modernization. The author briefly analyzes the actuality of population modernization in China, gives some advice and puts forward some measures. 相似文献
15.
This paper discusses the basic concept and connotation of population modernization. The author briefly analyzes the actuality of population modernization in China, gives some advice and puts forward some measures. 相似文献
16.
Sustainability science is a rapidly expanding field, particularly given the current ecological crises facing many parts of the globe today. To generate a snapshot of the state of sustainability science, we analyzed the current status of sustainability research using citation and text analysis. By reflecting social needs on sustainability science and the increasing number of publications in this field, the landscape is expected to change during the last decade. Our results indicate that previously separated research clusters investigating discipline-focused issues are becoming integrated into those studying coupled systems. We also found the existence of hub clusters bridging different clusters like socio-ecological systems and transition management. We also observed a variety of other emerging research clusters, especially in energy issues, technologies, and systems. Overall, our analysis suggests that sustainability science is a rapidly expanding and diversifying field, which has affected many disparate scientific disciplines and has the potential to feed scientific understanding on socio-ecological systems and to drive society toward transition for sustainability. 相似文献
17.
Progressive succession of plant communities has been studied in cutover areas of bilberry-green moss forests of the alliance Dicrano-Pinion in the central upland part of the Southern Urals. The results are presented concerning the alpha-diversity and phytosociological spectrum of communities at different stages of succession. 相似文献
18.
Specific features in the overgrowing of technogenically disturbed areas with completely destroyed soil and plant cover (a
sand pit, a causeway, and an off-road vehicle trail) have been studied in the environs of the Bovanenkovo Oil-Gas Condensate
Field. It is shown that the vegetation of natural ecotopes and ecotopes disturbed approximately 20 years ago is characterized
by a relatively high similarity in the composition of vascular plants. The total species composition of plant communities
(including mosses and lichens) and their structure show a considerable loss of floristic and phytocenotic diversity. 相似文献
19.
The population structure of the Colorado potato beetle in the Southern Urals is discussed. This population is shown to be divided into two groups of local populations, in central and in peripheral parts of the study area, which differ in degree of intrapopulation diversity. The founder effect and insecticide pressure are regarded as probable factors that have contributed to this division. 相似文献
20.
The degree of morphological differentiation of sable ( Martes zibellina L.) populations was studied in different physiographic regions of the Kamchatka Peninsula and the Penzhina River basin. According to craniometric data, the sables inhabiting the hilly Western Kamchatka Plain are larger than the animals from other regions. However, the analysis of phenetic variation in craniological characters and coat color showed that the sable samples taken within the peninsula were fairly homogeneous. On this basis, all sables inhabiting the Kamchatka Peninsula may be regarded as a single population. 相似文献
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