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1.
New experimental data on biological productivity of plant communities in oligotrophic and mesotrophic bogs of the middle taiga subzone over the past five years are presented. The relationship between net primary production and the stock of live phytomass is estimated. The stock of necromass in oligotrophic bog ecosystems increases from west to east, while the stock of live phytomass and net primary production decrease.  相似文献   
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青藏高原东北部气候变化的异质性及其成因   总被引:1,自引:1,他引:1  
利用1961-2016年西宁等青藏高原东北部13个气象台站气温、降水等气象资料以及国家气候中心发布的南海季风指数、西伯利亚高压指数等大气环流特征量数据,分析近56年来气候变化与高原主体的差异性及其可能的气候成因。研究表明:近56年来青藏高原东北部气候变暖趋势十分显著,年平均气温气候倾向率高达0.39 ℃/10 a,呈现出三次明显的阶梯性增高态势,并于1994年前后发生了由冷到暖的突变,同时具有明显的空间差异性;年降水量及四季降水量均没有明显变化趋势,虽然经历了2002年左右由少到多的变化,但并未出现明显突变,年降水量具有3年、5年的准周期,而年降水日数微弱减少,降水强度呈增加趋势;该区域气候变化的年际波动主要受到东亚季风、高原季风和南海季风的年际振荡及其相互作用的影响,而西风环流的作用并不明显,植被覆盖的恢复既是对2002年以来降水量增加的具体反应,同时也对于气候变暖趋势起到了一定的缓和作用。  相似文献   
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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   
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Under current climate change scenarios, temperatures in Siberia are expected to increase, and consequently, fire is also expected to increase. Potential climate-induced change is difficult to assess in Siberia because ground-based fire data are not complete. This investigation introduces a method by which potential climate-induced change can be remotely evaluated. Mean fire return intervals are established for 58 ecosystems across Siberia using eight years of satellite-based area burned data (1995 to 2002). Mean fire return intervals should decrease under current climate change scenarios, however the results do not currently demonstrate consistent evidence of fire-induced change. The overall boreal forest mean fire return interval is lower than the published mean, inferring increased fire. Most notably, using satellite data to calculate mean fire return intervals in individual ecosystems for the entire population of fire is shown to be a viable method by which potential climate-induced land cover change can be evaluated.  相似文献   
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Total column abundances of CO, HCN, C2H6, and C2H2 have been retrieved from infrared solar spectra observed at Moshiri (44.4°N) and Rikubetsu (43.5°N) in northern Japan from 1997 to 2005. The spectra were recorded with high spectral resolution ground-based Fourier transform infrared (FTIR) spectrometers and total column abundances were calculated by SFIT1 version 1.09e. Deviations of these species relative to their seasonal mean values (ΔCO, ΔHCN, ΔC2H6, and ΔC2H2) were derived, which showed short-time enhancements in 1998, 2002, and 2003. Good correlations among ΔCO, ΔHCN, ΔC2H6, and ΔC2H2 in a few months of each year were seen. Since the number of forest fires in Siberia had large enhancements in 1998, 2002, and 2003, trajectory analyses were performed in order to assess the influence of forest fires and it was confirmed that air masses passing over the location of burning points in Siberia reached Moshiri and Rikubetsu. This paper shows that enhancements of these species were driven by biomass burning in Siberia.  相似文献   
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Changes in climate, land-use and pollution are having disproportionate impacts on ecosystems and biodiversity of arctic and mountain ecosystems. While these impacts are well-documented for many areas of the Arctic and alpine regions, some isolated and inaccessible mountain areas are poorly studied. Furthermore, even in well-studied regions, assessments of biodiversity and species responses to environmental change are biased towards vascular plants and cryptogams, particularly bryophytes are far less represented. This paper aims to document the environments of the remote and inaccessible Altai-Sayan mountain mires and particularly their bryofloras where threatened species exist and species new to the regional flora are still being found. As these mountain mires are relatively inaccessible, changes in drivers of change and their ecosystem and biodiversity impacts have not been monitored. However, the remoteness of the mires has so far protected them and their species. In this study, we describe the mires, their bryophyte species and the expected impacts of environmental stressors to bring attention to the urgency of documenting change and conserving these pristine ecosystems.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01596-w.  相似文献   
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/ Implementation of environmental management in Russia is undergoing rapid changes. Federal responsibility rests with the Russian Federation State Committee for Environmental Protection (RFSCEP) and is delegated at regional level to local State Committees for Environmental Protection (SCEPs). This paper focuses on the functioning of the SCEP for Tomsk oblast' (region) in Siberia, which is strongly committed to forging constructive links with regional government, academia, industry, and environmental NGOs. Considerable difficulties exist for SCEPs in Russia, however, and prominent among these are (1) a rigidly vertical civil service structure, with separate organs having responsibility for different natural resources, persisting from Soviet times, which hinders effective intergrated and holistic environmental management; and (2) a lack of open access to environmental information from military and quasi-military sites.  相似文献   
9.
As part of the Russian FIRE BEAR (Fire Effects in the Boreal Eurasia Region) Project, replicated 4-ha experimental fires were conducted on a dry Scotch pine (Pinus sylvestris)/lichen (Cladonia sp.)/feathermoss (Pleurozeum schreberi) forest site in central Siberia. Observations from the initial seven surface fires (2000-2001) ignited under a range of burning conditions quantified the different fuel consumption and fire behavior characteristics (e.g., rate of spread, fireline intensity, etc.) possible in this particular forest fuel type. Experimental results and dendrochronological study of local fire history both support the dominance of local fire regimes by low to moderate-intensity surface fires. Carbon released by the experimental fires ranged from 4.8 to 15.4 t C ha− 1 depending on fuel conditions and fire severity. Preliminary emission data show a strong correlation between carbon dioxide (CO2) and carbon monoxide (CO) emissions, which should facilitate accurate estimates of fire impacts on atmospheric chemistry. Carbon concentration in smoke samples was related to fire severity. The short landscape-scale fire-return interval (50 years), combined with typically low fire severity, in pine ecosystems of central Siberia is often associated with low tree mortality and relatively rapid buildup of litter and understory fuels after a fire.  相似文献   
10.
Inter- and intraspecific effects of climate change were assessed for the dominant conifers of Siberia (60–140E and 48–75N): Larix spp. (L. sibirica, L. dahurica, and L. sukaczewii) and Pinus sylvestris . The approach employed a tri-variate (degree-days above 5 C, degree-days below 0 C, and a moisture index) estimate of the climatic envelope within which exists the actual ecological distribution of a species and their constituent climatypes (genotypes physiologically attuned to similar environments). Limits of the actual ecological distribution were approximated by reducing the climatic envelope according to effects of permafrost and interspecific competition. Climatypes were mapped within the climatic envelope according to the climatic interval that must separate populations for reasonable assurance of genetic differentiation. This interval was calculated from response functions that related 13-year growth and survival of a species to the difference in climate between the provenance of a climatype and the climate of numerous test sites distributed across Russia. Mapping species' distributions and their climatypes was done for the contemporary climate and for future climates predicted by the HadCM3GGa1 scenario of Hadley Centre. The results showed that if the forests of the future are to reflect the adaptedness of today, the distribution of species will shift and genotypes within species will be redistributed. Some contemporary climatypes are projected to disappear from Siberia while others common elsewhere would evolve. To mitigate these effects, climatypes should be transferred today to the expected future location of their climatic optima, a distance that is likely to approach 700–1200 km for these species.  相似文献   
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