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1.
Forest structure and regeneration along the altitudinal gradient in the Binsar Wildlife Sanctuary,Uttarakhand Himalaya,India 总被引:1,自引:0,他引:1
Forest structure and regeneration were studied along the altitudinal gradient in the Binsar Wildlife Sanctuary of Uttarakhand Himalaya in India. Stratified random sampling of tree species was done by placing minimum 15 quadrats of 10 × 10 m at each aspect and altitude. The results reveal that along the altitudinal gradient there were three types of forest communities in the Sanctuary viz., chir pine (Pinus roxburghii), oakchir pine (Quercus leucotrichophora and Pinus roxburghii) and oak (Quercus floribunda and Quercus leucotrichophora). Rhododendron arboreum, Cornus macrophylla and Lyonia ovalifolia were main associates of these forest communities. The oak forests had larger shrub population as compared to chir pine. Myrsine africana was the most dominant shrub across the altitudinal gradient, whereas few shrub species were restricted to a certain altitudinal range. The regeneration of chir pine was best at lower altitude on south and east aspects, which indicates that it mostly regenerates on warm and dry slopes. In general, the regeneration potential in most of the tree species declines with the altitude. The density of saplings and seedlings also represented the dominant species at each altitudinal range, which indicates the cyclic regeneration of forests in the Sanctuary area. 相似文献
2.
Wani Zishan Ahmad Samant Sher Singh Pant Shreekar 《Environment, Development and Sustainability》2022,24(4):4493-4510
Environment, Development and Sustainability - Natural colorants or dyestuffs are an essential faction of non-timber forest products that are widely used for coloring purposes in various industries.... 相似文献
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Pinus roxburghii (chir-pine) and Quercus leucothchophora (banj-oak) are dominant forests of mountainous part of the Uttarakhand Himalaya. The continued anthropogenic disturbance
is opening the canopy, forming canopy gaps and as a result forest fragments are developing. Thus, the present study aims to
analyze variations in species richness and vegetational parameters in relation to canopy gaps in forests. Total species richness
was greater in open canopied forest compared to moderate and close canopied forests. In comparison between oak and pine forest,
it was greater in oak forest while the proportion of common species was low between oak—pine forests. Mean species richness
did not significantly vary from one canopy gap to another as well as in oak and pine dominated forest. This indicated that
dominant forest types played an important role to form the community structure. The shrubs richness were greater in closed
canopy and between the forests it was greater in pine forest. Tree and shrub density was low in open canopy while herb density
was high in moderate canopy. Thus, this study indicated that the dominant canopy species play an important role in deciding
the community structures especially the distribution of under canopy species. These parameters should be considered for conservation
and maintenance of plant biodiversity of a region. 相似文献
4.
Zunić ZS Mietelski JW Błazej S Gaca P Tomankiewicz E Ujić P Celiković I Cuknić O Demajo M 《Journal of environmental radioactivity》2008,99(8):1324-1328
This paper reports results of gamma and alpha spectrometric measurements for mosses, lichens, fungi and soil samples from areas in the Balkans targeted by depleted uranium (DU). Samples were collected in 2002 and 2003 in the vicinity of several villages, principally Han Pijesak (Bosnia and Herzegovina, hit by DU in 1995) and Bratoselce (South Serbia, hit by DU in 1999) and in lesser numbers from Gornja Stubla, Kosovo (which is identified as a high natural radon/thoron area) and Presevo close to the Kosovo border. In the course of gamma spectrometric measurements some results suggested samples with unusual high uranium contents which might be considered to be a signature for the presence of DU, although many samples had very high detection limits. Alpha spectrometric measurements directly proved the presence of DU for five samples, all from directly targeted places. These were samples of mosses, lichens and soil. For some samples homogeneity tests were applied which showed a rather even distribution of DU in these samples. No trace of DU was found in any sample from a dwelling. 相似文献
5.
Contamination of polycyclic aromatic hydrocarbons (PAHs) in urban soils in Beijing, China 总被引:22,自引:0,他引:22
Soil contamination with polycyclic aromatic hydrocarbons (PAHs) is an increasing problem in many countries, including China. An extensive and systematic survey has been undertaken to evaluate the contamination with PAHs of urban soils in Beijing, China. Soil samples were collected from campuses of universities, schools and kindergartens, public squares, fallow land and roadsides, and were analyzed for 16 PAHs by GC-MS. There was a high variability in the total PAHs (SigmaPAHs) concentrations, ranging from less than 366 to 27,825 ng g(-1). The highest SigmaPAHs concentrations were found at roadsides and industrial sites. Soil organic carbon (SOC) is one of the important factors that can influence the concentrations of PAHs in soils. It was found that concentrations of SigmaPAHs were significantly correlated with that of soil organic carbon. To trace the sources of PAHs, the ratios of phenanthrene to anthracene and fluoranthene to pyrene were used to identify pyrogenic and petrogenic sources, respectively. In most cases, PAHs in soils in urban areas of Beijing were pyrogenic. These sources included motor vehicle exhausts, industrial activities and coal burning. These data can be further used to assess the health risk associated with soils polluted with PAHs. 相似文献
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Igliski B. Skrzatek M. Kujawski W. Cichosz M. Buczkowski R. 《Environment, Development and Sustainability》2022,24(1):77-111
Environment, Development and Sustainability - Renewable energy (RE) plays an increasingly important role in the economy of almost every country in the world. In order to examine the state of... 相似文献
8.
The distribution of heavy metals viz., Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb and Zn in the water, sediments, plants and fish samples collected from the Kali Nadi (India) have been determined. The studies have shown that there was considerable variation in the concentration of heavy metals from one sampling station to the other which may be due to the variation in the quality of industrial and sewage wastes being added to the river at different places. The orders of the concentration of heavy metals in water, sediments, plants (Eicchornia crassipes) and fish (Heteropnuestes fossilis) were Fe > Zn > Cu > Mn > Cr > Ni > Pb > Co > Cd; Fe > Zn > Mn > Ni > Cr > Co > Cu > Pb > Cd; Fe > Mn > Zn > Cu > Ni > Co > Pb > Cr > Cd and Fe > Zn > Mn > Ni > Pb > Co > Cr > Cu > Cd, respectively. 相似文献
9.
In the ladybird fauna of the steppe zone of the Southern Urals and the south of Western Siberia, five variants, three forms, and two habitus types of adult beetles are distinguished, and their hierarchy is established. The habitus diversity of ladybirds is revealed using a new method of describing each form in a polar system of coordinates whose center coincides with the center of gravity of the insect body. The system of ladybird habitus reflects the main directions of trophic specialization in the family. 相似文献
10.
A biological and geochemical integrated approach to assess the environmental quality of a coastal lagoon (Ravenna, Italy) 总被引:1,自引:0,他引:1
The assessment of the environmental quality of coastal lagoons is rather difficult as their intrinsic high variability limits the power of analytical chemistry and ecotoxicological approaches. Aim of the present work was to integrate geochemical and biological data which were simultaneously collected from the Pialassa Baiona lagoon (Ravenna, Italy), and evaluate the usefulness of a biomonitoring strategy based on sentinel organisms and biomarkers. Geochemical analysis on suspended, surface, and subsurface sediments were performed at five different sites of the lagoon; moreover the heavy metal bioaccumulation and a battery of biomarkers was evaluated in Mytilus galloprovincialis transplanted in the same sites. Heavy metals appeared to be diffused throughout the lagoon reaching higher levels in the southernmost sites, and mainly concentrated in suspended sediments. Lysosome membrane stability, neutral lipid and lipofuscin accumulation, and metallothionein levels in mussels indicated the development of a stress syndrome in animals exposed to the polluted sites. 相似文献
11.
To assess the stability of individual development of the pygmy wood mouse (Apodemus uralensis) in mountain areas with different ecogeographic conditions, the levels of fluctuating asymmetry in a series of skull phenes have been evaluated in ten samples from the Western and Central Caucasus. Attention has been focused on the influence of change in environmental conditions along the elevational gradient and the impact of some anthropogenic factors. An increase in the index of fluctuation asymmetry FAnm has been revealed in samples from populations exposed to pollutants and, in the absence of pollution, from areas where the average annual temperature drops below 5°С (mid-mountain regions). Instability of skull development observed in A. uralensis from the foothills of the Western Caucasus may be a consequence of competitive relationships with the Black Sea field mouse A. ponticus, a sympatric species that inhabits the same biotopes as does A. uralensis but numerically prevails over it. 相似文献
12.
In the diurnal lepidopteran fauna of the northern taiga subzone in the western Russian Plain, the species inhabiting primary biotopic complexes typical of this subzone currently account for slightly more than 60% of the total species richness and abundance. A large part of the fauna is represented by the species of more southern origin, whose expansion to the northern taiga was caused by anthropogenic transformation of landscapes between the 12th and 20th centuries and recent climate warming. 相似文献
13.
Diets of the Long-eared and Short-eared Owls, closely related species with overlapping ranges, have been studied in the south of Western Siberia (the Baraba Lowland) by analyzing bone remains in pellets. The results show that both species in the south of the Baraba Lowland employ similar strategies of food resource use, which, however, differ in some aspects. In the Short-eared Owl, the hunting range is apparently more restricted. During the nesting period, these birds occupy relatively moist habitats along riverbanks and protect their hunting grounds. The Long-eared Owl nests in mainly mesic habitats, in forest outliers, and can supplement its diet with shrews (Sorex) and steppe rodent species. The diets of both species largely consist of murine rodent species that are dominant or subdominant in the small mammal community of the Baraba forest-steppe. Seasonal and interannual variations in the food spectra of both species have been revealed. 相似文献
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In view of the extensive use of foraminifers for the pollution monitoring especially their unmatched utility in deciphering the temporal variation in the type and concentration of pollutants at a given location, the literature dealing with the application of foraminifers for pollution studies has been reviewed. The pollution monitoring through foraminifers started with attribution of peculiar foraminiferal features at any location to the circumstantial presence of pollutants at that site. These peculiar features of the foraminifers in polluted areas included, variation in the abundance of total, calcareous and agglutinated foraminifers, species diversity, abnormal tests, etc. The abnormalities of tests included stunted growth, abraded margins, dissolved ornamentations, etc. Initially, much attention was paid to the effects of sewage pollution on the foraminifers but later on all kinds of human induced as well as natural pollutants came under the preview of foraminiferologists working on pollution aspects. The advantage of application of foraminifers, over other chemical and biological techniques, for pollution monitoring lies in their potentiality to decipher temporal variation in type and concentration of pollutants at any site even in the absence of pre-pollution studies, based on the recovery of foraminifers from the sediment core samples. Realizing the potential application of characteristic foraminiferal features from the polluted areas to decipher the variation in introduction and concentration of pollutants at any given location with time, efforts were made to characterize the specific types of foraminiferal features to the specific pollutants. It was at this point that the need of culture studies was widely felt which resulted in numerous lab and field culture studies where foraminifers were subjected to specific pollutants in order to document their response to these pollutants and to develop effective foraminiferal proxies for pollution monitoring through time. Such studies are still going on and it is felt that culture studies need to be supplemented with advanced crystallographic and molecular studies in order to find the mechanism through which foraminifers respond to the pollutants. 相似文献
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Data are presented on the mutagenicity of an organic extract of a composite sample of urban air particulates and of thirty PAH compounds in such samples, including four quinone derivatives, isolated quantitatively by thin-layer chromatography and identified by fluorescence or other spectral techniques. Mutagenic activity was determined by the Ames assay, using histidine auxotrophs of Salmonella typhimurium strains TA98, TA100, TA1537 and TA1538. All compounds were dissolved in dimethyl sulfoxide (DMSO) which was the least toxic of eight organic solvents tested.The mutagenic activity of a benzene extract of suspended particulates from the air of Hamilton, Ontario was significantly greater with strain TA98 than with strain TA100, suggesting the presence of more frame-shift acting mutagens. The mutagenic response of this extract was similar with and without S-9 activation.Mutagenic tests on the 30 PAH compounds indicated that only the benzo(a)pyrene quinones were direct acting mutagens. All of the chemical compounds were tested with and without S-9 activation. The following PAH showed unequivocal mutagenic activity, with S-9 activation: benz(a)anthracene, benzo-(a)pyrene, benzo(ghi)perylene, benzo(rst)pentaphene, benzophenanthrene, chrysene, 1, 2, 3, 4-dibenzanthracene, 2, 3, 6, 7-dibenzanthracene, and 3-methyl cholanthrene. The quinones of 1, 6-; 3, 6-; and 6, 12-benzo(a)pyrenes showed weak mutagenic activity but 3, 6-benzo(a)pyrene elicited also a photodynamic response. 相似文献
18.
Climate change impacts,vulnerability and adaptive capacity of the electrical energy sector in Cyprus
The purpose of this study was to investigate the climate change impacts, vulnerability and adaptive capacity of the electrical energy sector in Cyprus. Spatial vulnerability of the island was assessed using the degree-day indicator to investigate heating and cooling demands in the near future using daily temperature projections from regional climate models (RCMs). Using daily electrical energy consumption data for the present climate, an impact model linking consumption and temperature was constructed and this relationship was projected to the future climate using the data from the RCMs and assuming the same technology use. Our impact model results showed that for the period between November and April (‘cold period’), a decreasing trend in electrical energy consumption is evident due to warmer conditions in the near future, while for the period between May and October (‘warm period’), an increasing trend in electricity consumption is evident as warmer conditions dominate by 2050. Regarding the spatial vulnerability assessment, the cooling degree-day indicator testified that major increases in cooling demand, between 100 and 200 degree-days, are expected in inland and southern regions during the summer in the near future. In addition, increases of about 20–50 degree-days are anticipated during autumn. Conversely, energy demand for heating is projected to decrease during spring and winter, especially in the higher elevation parts of the island. More precisely, reductions of about 30–75 degree-days are projected during spring, while greater reductions of about 60–90 degree-days are expected during winter in heating demand, especially for in the near future. The ability of the energy sector to adapt and follow these changes was deemed to be satisfactory reducing the overall vulnerability of the sector to future climate change. 相似文献
19.
Main trends in the formation of biotopic complexes of bumblebees in the northern taiga zone are analyzed. It is proposed that Eurasian forest species of bumblebees (Bombus (Th.) schrencki, B. (Mg.) consobrinus, etc.) are coadaptively connected with entomophilous plant species belonging to the synusia of Eurosiberian riverine-mountain meadow tall herbage, with the numbers of species in both biotic groups (pollinating insects and plants) and their abundance being greater in the landscape characterized by a high degree of karstification. In the biotopic bumblebee complex of a large river valley, the relative abundance of forest bumblebee species is 2.5–5.3 times lower than in other complexes, whereas that of meadow species is two orders of magnitude higher due to favorable thermal conditions and a large number of habitats with mesophilic herbage and legumes. Each of the distinct ecogeographic groups of bumblebees and the corresponding synusiae (each comprising entomophilous plants of different taxonomic groups) appear to be coadapted. This is probably a result of the diffuse coevolution of pollinators and plants belonging to the genetically unified biota. 相似文献
20.
Natural environment is fragile and harsh in Western China where rich energy and mineral resources are endowed,enabling energy and mining development to become a pillar industry of the regions socioeconomic development This paper identified the key issues and challenges faced by eco-environment as a result of energy and mining development in Western China.We argued mat mining and energy development have caused various environmental problems,and that environmental degradation is increasingly prominent in Western China,hence,we request coordinated resource development and environmental protection for sustainable development in this region.Based on the above recognitions,this paper put forward relevant policy recommendations:promoting green development vigorously and developing new green energy;formulating and enforcing environmental protection laws and regulations,improving ecological compensation mechanism;establishing green threshold;strengthening integration between western resource-based cities and coastal region to get rid of the"resource curse";improving energy and mineral resources development stakeholders’involvement;coordinating resource taxes and local development funds;and strengthening independent third-party supervision in the whole process of energy and mining development 相似文献