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591.
Behavioral adaptations of ant species were studied in associations of different biotopes in the Crimean Mountains. The pattern
of an association was found to depend on the mode of the territorial behavior of dominant species, irrespective of their number.
The dominance hierarchy was more strict in monodominant than in bidominant associations. Ant species demonstrated different
behavioral strategies, plasticity of foraging, and avoidance of aggressive encounters. A method for formalizing interspecies
relationships and a model describing stochastic properties of the biological system are proposed, which can be useful in solving
various ethological and ecological problems. 相似文献
592.
Christos Giannakopoulos Effie Kostopoulou Konstantinos V. Varotsos Kostas Tziotziou Achilleas Plitharas 《Regional Environmental Change》2011,11(4):829-843
Climate changes in the Mediterranean region, related to a significant increase in temperature and changes in precipitation
patterns, can potentially affect local economies. Agriculture and tourism are undoubtedly the most important economic sources
for Greece and these may be more strongly affected by changing future climate conditions. Climate change and their various
negative impacts on human life are also detected in their environment; hence this study deals with implications, caused by
changing climate, in urban and forest areas. Potential changes for the mid-twenty-first century (2021–2050) are analysed using
a high-resolution regional climate model. This paper presents relevant climatic indices, indicative for potential implications
which may jeopardise vital economic/environmental sectors of the country. The results provide insights into particular regions
of the Greek territory that may undergo substantial impacts due to climate change. It is concluded that the duration of dry
days is expected to increase in most of the studied agricultural regions. Winter precipitation generally decreases, whereas
an increase in autumn precipitation is projected in most areas. Changing climate conditions associated with increased minimum
temperatures (approximately 1.3°C) and decreased winter precipitation by 15% on average suggest that the risk for forest fires
is intensified in the future. In urban areas, unpleasantly high temperatures during day and night will increase the feeling
of discomfort in the citizens, while flash floods events are expected to occur more frequently. Another impact of climate
change in urban regions is the increasing energy demand for cooling in summer. Finally, it was found that continental tourist
areas of the Greek mainland will more often face heatwave episodes. In coastal regions, increased temperatures especially
at night in combination with high levels of relative humidity can lead to conditions that are nothing less than uncomfortable
for foreigners and the local population. In general, projected changes associated with temperature have a higher degree of
confidence than those associated with precipitation. 相似文献
593.
Quantitative methods have been applied to the study of floristic structure and diversity in Samarskaya Luka. The results show that Samarskaya Luka is a floristically heterogeneous area in which six elementary floras can be distinguished. This area has been assessed as a floristically autonomous formation, and its floristic representativeness was estimated. 相似文献
594.
In beaver ponds, the species diversity, abundance, biomass, and production of cladocerans and the amount of food consumed by them have increased and the composition of dominant species has changed as compared to those in the stretches of small rivers with running water or dammed by man. The stimulating effect of water from a beaver pond has been confirmed in laboratory experiments. The average number of juvenile Ceriodaphnia affinis produced by one female was considerably greater in this water than in the water from flowing and dammed (by man) river stretches. 相似文献
595.
V. A. Romanenkov J. U. Smith P. Smith O. D. Sirotenko D. I. Rukhovitch I. A. Romanenko 《Regional Environmental Change》2007,7(2):93-104
The Model of Humus Balance was used to estimate the influence of climate effects and changing agricultural practices on carbon
(C) levels in soddy–podzolic soils in the Russian Federation for the years 2000–2050. The model was linked with a spatial
database containing soil, climate and farming management layers for identification of spatial change of C sequestration potential.
Analysis of relationships between C, soil texture and climate indicated that compared with a business-as-usual scenario, adaptation
measures could increase the number of polygons storing soil organic carbon (SOC) by 2010–2020. The rate of possible C loss
is sensitive to the different climate scenarios, with a maximum potential for SOC accumulation expected in 2030–2040, thereafter
decreasing to 2050. The effect is most pronounced for the arid part of the study area under the emission scenario with the
highest rate of increase in atmospheric CO2 concentration, supporting findings from the dynamic SOC model, RothC. C sequestration during the study period was permanent
for clay and clay loam soils with a C content of more than 2%, suggesting that C sequestration should be focused on highly
fertile, fine-textured soils. We also show that spatial heterogeneity of soil texture can be a source of uncertainty for estimates
of SOC dynamics at the regional scale.
Figures in color are available at 相似文献
596.
The dependence of the annual increment of vegetative organs on air temperature and humidity and the amount of precipitation per phenophase, as well as the period of their growth in Scots pine, were studied in the forest-steppe zone of Cisbaikalia. The multiple effect of variation in environmental conditions on the annual increment of organs increased when precipitation in September of the previous year was taken into account. These factors proved to have a stronger effect on variation in the annual increment of needles (R 2 = 0.59, p = 0.00005) than that in the annual ring width (R 2 = 0.38, p = 0.0002). 相似文献
597.
598.
Yu. N. Litvinov S. A. Abramov V. Yu. Kovaleva A. V. Krivopalov E. A. Novikov A. I. Chechulin 《Russian Journal of Ecology》2007,38(6):413-418
The structural-temporal organization of a murine rodent community in the taiga has been studied near Lake Teletskoe, Mountain Altai. The results show that the long-term dynamics of indices characterizing community diversity depend mainly on changes in the structure of dominance rather than on the population dynamics of species. The distribution of species in the factor space corresponds to their preference for certain biotopes, from dry to relatively moist. An analysis of relationships within the rodent community has revealed the synchronous dynamics of species abundance and antiphase pattern of changes in the structural indices of dominant species. 相似文献
599.
Trends in plant cover synanthropization along a plain-foothills-mountains gradient have been revealed in the reserve. Characteristics of plant communities in anthropogenically disturbed habitats, centers of concentration of anthropophytes and apophytes, and pathways of their migration are described. 相似文献
600.
K. B. Gongalsky Zh. V. Filimonova A. D. Pokarzhevskii R. O. Butovsky 《Russian Journal of Ecology》2007,38(1):52-57
The influence of the Kosogorsky Metallurgical Plant (KMP; Tula region, Russia) on the abundance and biodiversity of carabid beetles and soil macrofauna and on the trophic activity of soil biota was studied. Metal concentrations in the impact plot were many times higher than those in the control plot located on the same transect. As the transect approached KMP, both the abundance of soil invertebrates (geobionts) and trophic activity of the soil biota remained unchanged, whereas the abundance and diversity of carabids (herpetobionts) decreased drastically. It is suggested that the impact of the KMP on herpetobionts is accounted for by modification of the structure of ecosystems and that herpetobiontic and geobiontic groups of the macrofauna respond differently to this impact because of differences in the ecological mechanisms of population response. 相似文献