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871.
The probable source of stone moroko, Pseudorasbora parva (Temminck & Schlegel, 1846), populations in lake- and stream-type Dnieper reservoirs was revealed. The dynamics and specific growth rates of these populations over 20 years were analyzed. The dynamic phase portrait method was used to determine the timing of stages in the process of invader naturalization and the periods when its populations were in equilibrium. The potential growth rates of P. parva populations in the Kremenchug and Dneprodzerzhinsk reservoirs were estimated.  相似文献   
872.
Fluctuating asymmetry (FA) of the mandible shape has been analyzed in bank voles from the zones affected by pollution from three copper smelters in the Urals. It has been shown that there is the necessity for a detailed analysis of the material, since the level of FA may depend on population parameters. Regardless of the pollution level, FA of the mandible region including the lower part of the mandibular body, ramus and processes is higher than in the diastema region. A gradient effect of toxic exposure on FA has been revealed: an increase in its level under increasing technogenic impact is clearly manifested along local pollution gradients.  相似文献   
873.
The dynamics and correlations of ecophysiological parameters have been studied in two spatially separated multispecies communities of murine rodents and ixodid tick larvae and nymphs that parasitize them. It has been shown that all the processes under consideration have nonstationary, oscillatory dynamics. The long-term dynamics of connectivity of ecophysiological characteristics within communities and their synchronization by weather–climatic factors are, by nature, wavelike processes of transitions between the states with stronger and weaker linkage between parameters, which, along with nonstationarity, can contribute to the maintenance of stability and integrity of communities.  相似文献   
874.
This article outlines problems related to the location of facilities designed to treat the organic fraction of municipal solid waste (OFMSW). Anaerobic digestion (AD) facilities are investigated as a treatment option, while taking into account the aspects of renewable energy generation. This research has been spurred on by the relationship between waste management, energy generation issues and spatial planning procedures. The analysis is focused on urban and semi-urban areas of medium and large cities. One of the most difficult issues associated with siting of waste processing plants is its integration with local infrastructures, avoiding conflicts and negative environmental impacts at the same time. This research aims to analyse possible locations for AD plants fuelled by OFMSW in Poland. Based on the experience gained from other countries and lessons learnt from the analysis of existing facilities in Europe, conditions for the location of this type of waste treatment plants have been defined, with the focus on economic, environmental and social issues. Most likely, the results of the multicriteria decision analysis for siting of municipal solid waste AD plants (M-BIST tool) could be transferred to other countries, especially those with a comparable GDP level and a similar framework for a waste management system.  相似文献   
875.
Transport infrastructure is particularly vulnerable to climate impacts as it is designed for long operational lives, and both episodic and seasonal conditions contribute to deterioration, disruption and unsafe incidents. There are some examples of adaptation in transportation design, but many communities do not have the capacity to incorporate climate change considerations into infrastructure planning and management. Researchers worked closely with the City of Prince George, in Central British Columbia, Canada, to build on existing work and explore how the City could plan, design, and maintain roads and other structures to account for climate change. A local steering committee was formed, and created and evaluated 23 potential research topics. Two focus areas were selected for further investigation and explored during a workshop with practitioners, researchers, consultants and other representatives. The workshop precipitated an investigation of projected impacts of climate change on road maintenance and road safety, and plans to explore alternative paving techniques. Outcomes of the case study provide insights regarding climate change and local transportation infrastructure, including: how researchers can engage with local experts to explore adaptation; issues local governments perceive as important; and barriers communities face as they attempt to address vulnerabilities.  相似文献   
876.
Increasing value is attributed to mangroves due to their considerable capacity to sequester carbon, known as ‘blue carbon’. Assessments of opportunities and challenges associated with estimating the significance of carbon sequestered by mangroves need to consider a range of disciplinary perspectives, including the bio-physical science mangroves, social and economic issues of land use, local and international law, and the role of public and private finance. We undertook an interdisciplinary review based on available literature and fieldwork focused on parts of the Mekong River Delta (MRD). Preliminary estimates indicate mangrove biomass may be 70–150 t ha?1, but considerably larger storage of carbon occurs in sediments beneath mangroves. These natural stores of carbon are compromised when mangroves are removed to accommodate anthropogenic activities. Mangroves are an important resource in the MRD that supplies multiple goods and services, and conservation or re-establishment of mangroves provides many benefits. International law and within-country environmental frameworks offer increasing scope to recognize the role that mangrove forests play through carbon sequestration, in order that these might lead to funding opportunities, both in public and private sectors. Such schemes need to have positive rather than negative impacts on the livelihoods of the many people living within and adjacent to these wetlands. Nevertheless, many challenges remain and it will require further targeted and coordinated scientific research, development of economic and social incentives to protect and restore mangroves, supportive law and policy mechanisms at global and national levels, and establishment of long-term financing for such endeavours.  相似文献   
877.
Pollution-induced illnesses are caused by toxicants that result from human activity and are often entirely preventable. However, where industrial priorities have undermined responsible governance, exposed populations must reduce their exposure by resorting to voluntary protective measures and demanding emissions abatement. This paper presents a coupled human–environment system model that represents the effects of water pollution on the health and livelihood of a fishing community. The model is motivated by an incident from 1949 to 1968 in Minamata, Japan, where methylmercury effluent from a local factory poisoned fish populations and humans who ate them. We model the critical role of risk perception in driving both social learning and the protective feedbacks against pollution exposure. These feedbacks are undermined in the presence of social misperceptions such as stigmatization of the injured. Through numerical simulation and scenario analysis, we compare our model results with historical datasets from Minamata, and find that the conditions for an ongoing pollution epidemic are highly unlikely without social misperception. We also find trade-offs between human health outcomes, the viability of the polluting industry and the survival of the fishery. We conclude that an understanding of human–environment interactions and misperception effects is highly relevant to the resolution of contemporary pollution problems, and merits further study.  相似文献   
878.
879.
The dynamics and structure of the phytomass and production of an undisturbed mesotrophic dwarf shrub–sphagnum phytocenosis and one burned by fire have been compared. The net primary production (NPP) of both sites of phytocenoses in the postpyrogenic period is estimated by direct field determination of the productivity parameters, and C emission from the fire is assessed. The obtained data on emission (0.7 kg/m2) differ from the results obtained in the peatlands of western Canada (3.2 kg/m2).  相似文献   
880.
Patterns of expansion of geographical ranges of red deer and Siberian roe deer in Yakutia during the 20th century are considered. The area inhabited by red deer in Yakutia has increased almost fourfold over the past 50 years, with an expansion of over 200000 km2 toward the northwest. The geographical range of roe deer in the Lena–Amga interfluve has also changed considerably during the same period. Roe deer sightings in the subarctic zone were reported. The structure of geographical ranges of the species under investigation in different ecological and geographical regions of Yakutia is discussed, and the factors influencing the transformation of geographical range borders are characterized.  相似文献   
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