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1.
V. N. Orlov Yu. M. Borisov S. Yu. Irkhin A. A. Kovaleva 《Russian Journal of Ecology》2010,41(6):519-523
The distribution of three chromosome races (Moscow, Western Dvina, and Seliger) of the common shrew Sorex araneus L. in the zone of contact between their ranges in the Valdai Heights (32°00′ E, 57°00′ N) is discussed. The area co-inhabited
by all the three races is extremely small. Representatives of all the three races have been captured on only one trap line,
although there are no obstacles to the expansion of shrews. The extremely small area co-inhabited by the three races, as well
as the strictly parapatric distribution of the Moscow and Western Dvina races, may be related with competition forms such
as avoidance of contacts and separation of ecological niches. 相似文献
2.
The mid altitudinal oak, Quercus floribunda forms predominantly evergreen forest in Central Himalaya between 2000–2400 m. It is late successional, mature phase species
that has limited regeneration on disturbance prone sites. This oak produces mast seed crops at an interval of 2–3 years. During
masting in Q. floribunda the seed fall and germination is upto ten times greater than in normal years, emphasizing the importance of mast year crop
in forest maintenance. However, no mast year in this species since the last nine years (1997–2005) is a matter of serious
concern. The rise in the summer and winter temperature over a period of 15 years appear to have affected the frequency of
masting in this oak. The importance of masting can be adjudged from the fact that 97% of the surviving seedlings m−2 are of the mast year crop. 相似文献
3.
Sea-level rise impacts on Africa and the effects of mitigation and adaptation: an application of DIVA 总被引:2,自引:0,他引:2
Jochen Hinkel Sally Brown Lars Exner Robert J. Nicholls Athanasios T. Vafeidis Abiy S. Kebede 《Regional Environmental Change》2012,12(1):207-224
This paper assesses sea-level rise impacts on Africa at continental and national scales including the benefits of mitigation
and of applying adaptation measures, considering four scenarios of global mean sea-level rises from 64 to 126 cm in the period
of 1995–2100. We find that in 2100, 16–27 million people are expected to be flooded per year, and annual damage costs range
between US5 and US 5 and US 9 billion, if no adaptation takes place. Mitigation reduces impacts by 11–36%. Adaptation in the form
of building dikes to protect against coastal flooding and nourishing beaches to protect against coastal erosion reduces the
number of people flooded by two orders of magnitude and cuts damage costs in half by 2100. Following such a protection strategy
would require substantial investment. First, Africa’s current adaptation deficit with respect to coastal flooding would need
to be addressed. DIVA suggests that a capital investment of US300 billion is required to build dikes adapted to the current surge regime and US 300 billion is required to build dikes adapted to the current
surge regime and US 3 billion per year for maintenance. In addition, between US2 and US 2 and US 6 billion per year needs to be
spent on protecting against future sea-level rise and socio-economic development by 2100. This suggests that protection is
not effective from a monetary perspective but may still be desirable when also taking into account the avoided social impact.
We conclude that this issue requires further investigation including sub-national scale studies that look at impacts and adaptation
in conjunction with the development agenda and consider a wider range of adaptation options and strategies. 相似文献
4.
Regional Siberian studies have already registered climate warming over the last several decades. We evaluated ongoing climate
change in central Siberia between 1991 and 2010 and a baseline period, 1961–1990, and between 1991 and 2010 and Hadley 2020
climate change projections, represented by the moderate B1 and severe A2 scenarios. Our analysis showed that winters are already
2–3°C warmer in the north and 1–2°C warmer in the south by 2010. Summer temperatures increased by 1°C in the north and by
1–2°C in the south. Change in precipitation is more complicated, increasing on average 10% in middle latitudes and decreasing
10–20% in the south, promoting local drying in already dry landscapes. Hot spots of possible forest shifts are modeled using
our Siberian bioclimatic vegetation model and mountain vegetation model with respect to climate anomalies observed pre-2010
and predicted 2020 Hadley scenarios. Forests are predicted to shift northwards along the central Siberian Plateau and upslope
in both the northern and southern mountains. South of the central Siberian Plateau, steppe advancement is predicted that was
previously non-existent north of 56°N latitude. South of 56°N, steppe expansion is predicted in the dry environments of Khakasiya
and Tyva. In the southern mountains, it is predicted that the lower tree line will migrate upslope due to increased dryness
in the intermontane Tyvan basins. The hot spots of vegetation change that are predicted by our models are confirmed by regional
literature data. 相似文献
5.
A comparative analysis of the spatial-ethological structure of social vole (Microtus socialis Pall.) colonies was made on the basis of studies performed in Dagestan (1987–1991) and the southern Kalmyk Republic (1993–1998).
Notwithstanding differences in environmental conditions and the extent and forms of anthropogenic impact, the population structure
of the species proved to be similar and stable. Irrespective of population density, its core consists of family groups. Specific
features of social behavior (aggressiveness toward unfamiliar animals) provide for the protection of home ranges and help
to maintain a stable population structure. 相似文献
6.
G. F. Nekrasova O. S. Ushakova A. E. Ermakov M. A. Uimin I. V. Byzov 《Russian Journal of Ecology》2011,42(6):458-463
Effects of copper ions and copper oxide nanoparticles on lipid peroxidation rate, activities of anti-oxidant enzymes (superoxide
dismutase, catalase, and peroxidase), and photosynthesis have been studied in experiments with Elodea densa Planch. The results show that nanoparticles are more actively accumulated by plants. Both copper ions and nanoparticles activate
lipid peroxidation (to 120 and 180% of the control level, respectively). Catalase and superoxide dismutase activities in plants
treated with nanoparticles increase by a factor of 1.5–2.0. Copper ions suppress photosynthesis at a concentration of 0.5
mg/l, whereas nanoparticles produce such an effect only at 1.0 mg/l. The observed effects of different forms of copper on
E. densa are discussed in a comparative aspect. 相似文献
7.
Collections made in the course of long-term field studies on ecology of the northern mole vole Ellobius talpinus Pall. in the Ural Region and neighboring areas (more than 2000 individuals from 24 points of the species range) were used
to analyze geographic variation in its coat color (color morphs). On the basis of long-term observations (1985–1999) on marked
animals from a polymorphic population (Kurtamyshskii raion, Kurgan oblast), the life spans of males and females and the dependence
of life span on population density and structure were estimated in animals of different color morphs. Each color morph of
E. talpinus was shown to have specific features of the seasonal dynamics of age structure and migrations. 相似文献
8.
Panos Hadjinicolaou Christos Giannakopoulos Christos Zerefos Manfred A. Lange Stelios Pashiardis Jos Lelieveld 《Regional Environmental Change》2011,11(3):441-457
We present climate change projections and apply indices of weather extremes for the Mediterranean island Cyprus using data
from regional climate model (RCM) simulations driven by the IPCC A1B scenario within the ENSEMBLES project. Daily time-series
of temperature and precipitation were used from six RCMs for a reference period 1976–2000 and for 2026–2050 (‘future‘) for
representative locations, applying a performance selection among neighboring model grid-boxes. The annual average temperatures
of the model ensemble have a ±1.5°C bias from the observations (negative for maximum and positive for minimum temperature),
and the models underestimate annual precipitation totals by 4–17%. The climatological annual cycles for the observations fall
within the 1σ range of the 6-model average, highlighting the strength of using multi-model output. We obtain reasonable agreement
between models and observations for the temperature-related indices of extremes for the recent past, while the comparison
is less good for the precipitation-related extremes. For the future, the RCM ensemble shows significant warming of 1°C in
winter to 2°C in the summer for both maximum and minimum temperatures. Rainfall is projected to decrease by 2–8%, although
this is not statistically significant. Our results indicate the shift of the mean climate to a warmer state, with a relatively
strong increase in the warm extremes. The precipitation frequency is projected to decrease at the inland Nicosia and at the
coastal Limassol, while the mountainous Saittas could experience more frequent 5–15 mm/day rainfall. In future, very hot days
are expected to increase by more than 2 weeks/year and tropical nights by 1 month/year. The annual number of consecutive dry
days shows a statistically significant increase (of 9 days) in Limassol. These projected changes of the Cyprus climate may
adversely affect ecosystems and the economy of the island and emphasize the need for adaptation strategies. 相似文献
9.
To better understand how Batrachupems tibetanus responds to different temperature regimes in the blood parameters and to estimate the change in plasma cortisol level in
this species exposed to different temperatures, the animals were stochastically divided into three groups and exposed respectively
to 4.6°C, 14.6°C and 19.6°C for 12 days. The concentrations of glucose, total protein, albumin, triacylglycerol, Ca2+, K+, Na+, Cl−, and plasma cortisol level were measured respectively. There was no significant difference between the plasma cortisol level
of the control group and the experiment groups. Glucose level at 4.6°C and 19.6°C was significantly lower than glucose level
at 14.6°C. The plasma triacylglycerol level was significantly influenced by acclimation temperature. The concentration of
total protein, albumin, globulin and the ratio between albumin and globulin were not significantly influenced by temperature
when compared with control group. There was no significant change in concentration of Ca2+ at different temperatures. The concentration of K+ was significantly influenced by temperature. Plasma K+ level significantly increased at 19.6°C. The plasma Na+ level and Cl− were significantly influenced by temperature. Na+: Cl− ratio was significantly influenced by temperature. Therefore, glucose, triacylglycerol, Na+ and Cl− levels could be considered as indicators of thermal stress in B. tibetanus; plasma cortisol, albumin, globulin levels, and albumin/globulin ratio are not influenced by temperature. 相似文献
10.
Perceptions of climate change,multiple stressors and livelihoods on marginal African coasts 总被引:1,自引:0,他引:1
Matthew Bunce Sergio Rosendo Katrina Brown 《Environment, Development and Sustainability》2010,12(3):407-440
Studies of multiple stressors in Africa often focus on vulnerable inland communities. Rising concentrations of the world’s
poor live in coastal rural–urban areas with direct dependencies on marine as well as terrestrial ecosystem goods and services.
Using participatory methods we elicited perceptions of stressors and their sources, impacts and consequences held by coastal
communities in eastern Africa (Mtwara in Tanzania and Maputo in Mozambique). Respondent-informed timelines suggest wars, economic
policies and natural increase have led to natural resource-dependent populations in marginal, previously little-inhabited
lowland coastal areas. Respondents (n = 91) in interviews and focus groups rank climate stressors (temperature rise/erratic rain) highest amongst human/natural
stressors having negative impacts on livelihoods and wellbeing (e.g., cross-scale cost of living increases including food
and fuel prices). Sources of stress and impacts were mixed in time and space, complicating objective identification of causal
chains. Some appeared to be specific to coastal areas. Respondents reported farms failing and rising dependence on stressed
marine resources, food and fuel prices and related dependence on traders and credit shrunk by negative global market trends.
Development in the guise of tourism and conservation projects limited access to land–sea livelihoods and resources in rural–urban
areas (coastal squeeze). Mental modelling clarified resource user perceptions of complex linkages from local to international
levels. We underline risks of the poor in marginal coastal areas facing double or multiple exposures to multiple stressors,
with climate variability suggesting the risks of climate change. 相似文献
11.
The impact of global warming on winter tourism and skiing: a regionalised model for Austrian snow conditions 总被引:2,自引:1,他引:1
Possible climate change will modify snow-cover depth and change the characteristics of winter tourism and skiing districts.
Our model describes seasonal snow-cover depth related to altitude in six Alpine climate regions as the best fit of all snow
stations. Data cover 30 winter seasons (November to April values) from 1965 to 1995. We modified the data according to a scenario
of temperature and precipitation change (2 °C warming, no precipitation change) and achieve a new simulated snow-cover depth.
The indicators MARP (mean altitude of resident population) and MASPSL (mean altitude of starting point of ski lifts) serve
as references for “critical altitudes” of Austrian districts. A warming implies a reduction of snow in all districts, but
the loss is overproportional in lower altitudes. The direction of economic impacts is clear – income losses and adaptation
costs – but magnitude and time frames remain uncertain.
Received: 24 February 1999 · Accepted: 15 May 1999 相似文献
12.
N. G. Smirnov E. A. Kuz’mina I. B. Golovachev T. V. Fadeeva 《Russian Journal of Ecology》2007,38(2):106-111
On the basis of abundant fossil and subfossil bone remains, the ecological and faunal role of the narrow-skulled vole in zonal
rodent communities of northern Eurasia is analyzed over the period from the Late Pleistocene to the present time. Special
attention is given to the correlated dynamics of relative abundance of Microtus gregalis and other rodent species in the course of transition from one zonal type to another and to specific features of this correlation
in the southern, middle, and northern parts of the species range. It is shown that distinctive dimensional and morphotypic
features of the two currently existing subspecies, Microtus gregalis major Ogn. and M. g. gregalis Pall., are the product of concordant development of the species and environmental conditions in the past 3000–4000 years
(transition from the Holocene optimum to the present-day climate and state of the natural environment).
Published in Russian in Ekologiya, 2007, Vol. 38, No. 2, pp. 117–123.
The article was translated by the authors. 相似文献
13.
VALUING ECOSYSTEM SERVICES OF CHILEAN TEMPERATE RAINFORESTS 总被引:1,自引:0,他引:1
LAURA NAHUELHUAL PABLO DONOSO ANTONIO LARA DAISY NÚÑEZ CARLOS OYARZÚN EDUARDO NEIRA 《Environment, Development and Sustainability》2007,9(4):481-499
The Valdivian Rainforest Ecoregion (35°–48° S) in southern South America is among the ecosystems with highest conservation
priority worldwide due to its rich diversity, degree of endemism, and critical conservation status. Temperate rainforests
in this vast area are essential as source of biological resources and to maintain different ecosystem services which remain
largely unmeasured and unvalued. Consequently, the benefits they provide are not reflected in decision-making regarding forest
management and conservation. Based on existing studies and results from ongoing research we describe selected ecosystem services
and provide estimates of their economic value. Timber benefits for secondary forests expressed as net present stumpage values
were US$ 3742 ha−1 and US$ 3093 ha−1 for sustainable forest management (SFM) and unsustainable harvesting, respectively. Timber benefits for old growth forests␣equaled
US$ 4546 ha−1 and US$ 5718 ha−1, for SFM and unsustainable harvesting, respectively, using an 8% discount rate. Annual benefits from recreation were US$
1.6 ha−1 and US$ 6.3 ha−1 for the two most important national parks located in the study area. The annual value of maintaining soil fertility was US$
26.3 ha−1 using the replacement cost of nutrient losses due to soil erosion. The annual economic value of water supply for human consumption
using the production function method was US$ 235 ha−1. These results provide valuable information on the kind and magnitude of values that could be relevant in decision-making
concerning conservation and management of native forests in the Valdivian Rainforest Ecoregion. 相似文献
14.
O. V. Yastrebova E. G. Plotnikova L. N. Anan’ina V. A. Demakov 《Russian Journal of Ecology》2009,40(7):516-521
Seven strains of Gram-positive microorganisms capable of forming endospores have been isolated from soils of the region of
potassium salt mining (Berezniki, Perm krai) by the method of enrichment cultures. Their typing by means of REP- and BOX-PCR
has shown that four strains—I23 (= VKM V-2504), I26 (= VKM V-2505), I27, and I28—are of the same genogroup (type I), while
strains SN501 (= VKM V-2508), I10b (= VKM V-2507), and I12b (= VKM V-2506) represent three different genogroups (types II,
III, and IV, respectively). A phylogenetic analysis of 16S rRNA gene sequences has shown that strains I10b and SN501 belong
to the genus Paenibacillus, and the remaining strains, to the genus Bacillus. These bacteria are tolerant of high salinity and alkalinity: they can grow at pH 7.0–9.0 and NaCl content of 90–110 g/l
in the culture medium. They are also capable of utilizing diesel fuel and individual aromatic and aliphatic hydrocarbons. 相似文献
15.
A. J. Plater J. F. Boyle C. Mayers S. D. Turner R. W. Stroud 《Regional Environmental Change》2006,6(1-2):71-85
The limnological record of human impact on catchment land cover and on lake sedimentation during the historical period has
been established for Pinto Lake in Central Coastal California. In addition, the sedimentary record of the ‘pre-impact’ condition
preserves evidence of a climatic control on the nature of lake sedimentation. Chronological marker horizons have been determined
using pollen data in combination with the documented land-use history and introductions of exotic species. Further chronological
data have been determined using 14C and 137Cs. The impact of Mexican and Euro-American immigrants and their ‘imported’ land-use practices is clearly reflected in an
order of magnitude increase in the rate of lake sedimentation to c. 9 kg m−2 year−1 (c. 2 cm year−1) between 1770 and 1850. Here, the occurrence of exotic plant species indicates disturbance as early as c. 1769–1797, whilst
redwood deforestation between 1844 and 1860 represents the most significant human impact. Changes in the nature of sedimentation
prior to this reveal a high degree of sensitivity to changes in precipitation where subtle decreases in lake level and the
supply of runoff-derived mineral matter have resulted in two periods of organic lake sedimentation c. 650–900 and 1275–1750. Set against this background condition of high sensitivity, the dramatic impacts of Euro-American settlement
are unsurprising.
An erratum to this article can be found at 相似文献
16.
Rupert Seidl Mart-Jan Schelhaas Marcus Lindner Manfred J. Lexer 《Regional Environmental Change》2009,9(2):101-119
To study potential consequences of climate-induced changes in the biotic disturbance regime at regional to national scale
we integrated a model of Ips typographus (L. Scol. Col.) damages into the large-scale forest scenario model EFISCEN. A two-stage multivariate statistical meta-model
was used to upscale stand level damages by bark beetles as simulated in the hybrid forest patch model PICUS v1.41. Comparing
EFISCEN simulations including the new bark beetle disturbance module against a 15-year damage time series for Austria showed
good agreement at province level (R2 between 0.496 and 0.802). A scenario analysis of climate change impacts on bark beetle-induced damages in Austria’s Norway
spruce [Picea abies (L.) Karst.] forests resulted in a strong increase in damages (from 1.33 Mm3 a−1, period 1990–2004, to 4.46 Mm3 a−1, period 2095–2099). Studying two adaptive management strategies (species change) revealed a considerable time-lag between
the start of adaptation measures and a decrease in simulated damages by bark beetles. 相似文献
17.
This paper examines the issue of ancillary benefits by linking sulfur dioxide (SO2) emission to CO2 emission using a panel of 29 Chinese provinces over the period 1995–2007. In the presence of non-stationarity and cointegrating
properties of these two data series, this paper applies the panel cointegration techniques to examine both the long-run and
short-run elasticities of SO2 with respect to CO2. The major findings are that: (1) there exhibits a stable long-run equilibrium relationship between the SO2 and CO2 emission with the long-run elasticity being 2.15; (2) there exists a short-run relationship between these two emissions with
the short-run elasticity being 0.04. In addition, following an exogenous shock that causes a deviation from the long-run equilibrium,
it would take approximately 15 years for SO2 emission to revert toward the long-run equilibrium path with an average annual convergence rate of 6.5%; (3) the derived
ancillary benefits that is generated from one metric ton of CO2 emission reduction, are 11.77 Yuan (approximately US1.7) in the short run and 196.16 Yuan (US 1.7) in the short run and 196.16 Yuan (US 30) in the long run. These
findings are not only crucial from the econometric modeling perspective, but also have important policy implications. 相似文献
18.
Gradients of genetic distances (GGDs) between 26 adjacent cenopopulations of Scotch pine (Pinus sylvestris L.) along the transects through the distinct landscape-ecotopic isolation borders were analyzed graphically. The results
made it possible to reveal and quantitatively estimate gradients and borders of gene-pool structural patterns in populations
of this species in the central part of Northern Eurasia. In lowland areas, the most distinct borders were found between pine
populations growing on dry lands and bogs (Pineta sphagnosa) in the forest zone of the Transural region, as well as between the Arakaragaiskii and Amankaragaiskii island pine forests
in the steppe zone (Northern Turgai). In highland areas (the Urals and the Carpathians), the greatest GGDs were observed between
low-mountain (about 600 m above sea level) and middle-mountain (850–900 m) populations. Analysis of GGDs is a promising gene-geographic
method for determining population borders and studying the chorogenetic structure of species. 相似文献
19.
Fuelwood is the only important source of energy in the mountainous region of the Garhwal Himalaya, India. Since the commercial
source of energy is generally beyond the reach of ordinary people due to their poor socio-economic conditions and due to limited
supply and lack of communication facilities for transport of LPG, the villages of the inner region of the Garhwal Himalaya
depend on their fuel requirement from the forest. In the present study, two villages of the Nanda Devi Biosphere Reserve in
Uttarakhand part of the Indian Himalaya i.e. Lata and Dunagiri located at 2,415 and 3,600 m altitudes, respectively, were
selected for the study of socio-economic profile and vegetation and for estimation of per capita fuelwood consumption and
the degree of disturbance. The study was conducted from 2002–2005. The population of these villages is migratory and belongs
to the Bhotiya community, a scheduled tribe consisting of two subgroups known as Tolcha and Marchha. They grow traditional crops as well as cash crops. Important tree species used for fuelwood include Cedrus deodara, Pinus wallichiana, Cupressus torulosa, Taxus wallichiana, Acer indicum, Quercus dilatata and Viburnum cotinifolium. Maximum density among trees was shown by Pinus wallichiana (169.6 trees ha−1) in village Lata and by Cedrus deodara (89.6 trees ha−1) in village Dunagiri. The average per capita consumption of fuelwood in villages Lata and Dunagiri was 4.03 and 4.77 kg capita−1 day−1. Maximum number of trees (29 and 31% lopping for Lata and Dunagiri, respectively) belonged to disturbance class 1 (1–20%
lopping) followed by the disturbance class 2 (20–40% lopping). Due to location of these villages in the buffer zone of the
biosphere reserve, the fuelwood consumption may cause an adverse impact on the ecological status of this reserve, which urgently
requires employing strategies for the conservation and management of this biosphere in terms of fuelwood sustainability e.g.
regulation of livestock stock and grazing, using alternative sources of fuels, plantation of multipurpose trees and adoption
of ecotourism. 相似文献
20.
Holocene fire history from the Greater Blue Mountains World Heritage Area, New South Wales, Australia: the climate, humans and fire nexus 总被引:2,自引:1,他引:1
This study presents a reconstruction of the fire activity of the last ~14,200 cal. years BP (before AD 1950) from Gooches Crater Right, located on the Newnes Plateau, approximately 150 km to the west of Sydney (~33°27′S, 150°16′E)
within the Blue Mountains National Park. Charcoal analysis and palynology were undertaken with the aim of untangling any inter-relationship
between climate, humans and fire. A chronology of the site was provided by radiocarbon dating. The dominant control on fire
in this environment during the Holocene appears to be climate. Periods of climate change, identified in previous studies,
are associated with higher levels of fire activity. Fire was less ubiquitous between ~9,000 and 6,000 years BP, a period normally
described as having a higher effective moisture in south-eastern Australia. The mid-Holocene fluctuations in charcoal may
reflect anthropogenic fire, climate forcing or alternatively human responses to any climate change. Coeval changes in palaeoclimatic
sequences elsewhere and palynology at the site support a climatic explanation or that Aboriginal people used fire within a
climatic framework. 相似文献