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941.
942.
Thaddeus Chidi Nzeadibe Chukwuedozie K. Ajaero 《Environment, Development and Sustainability》2011,13(1):163-177
Solid waste management (SWM) in many low- and middle-income countries is sometimes driven by the informal sector. Unfortunately,
contributions of the sector to SWM are not acknowledged in many developing countries. This situation often arises from inadequate
awareness and lack of advocacy for these development contributions. This article reports on the impact of a study conducted
by final-year geography undergraduates on the informal waste management sector in Nsukka urban area, Nigeria. The purposes
of this exercise were to stimulate development intervention on behalf of the sector to improve perceptions, attitudes and
performance, to impart a range of development research skills and to expose the students to the business opportunities provided
by SWM and recycling. Informal waste sector workers and government officials responsible for SWM were interviewed, and some
commercial data on recycling operations were collected. Findings of this study indicate that such advocacy initiatives were
effective in increasing students’ awareness of opportunities and interest in working in the informal waste sector to promote
better SWM and development in Nigeria. Lessons from this university case study are also drawn for other developing countries
struggling to achieve the poverty reduction and job creation Millennium Development Goals (MDGs). 相似文献
943.
Julius H. Kotir 《Environment, Development and Sustainability》2011,13(3):587-605
Sub-Saharan Africa has been portrayed as the most vulnerable region to the impacts of global climate change because of its
reliance on agriculture which is highly sensitive to weather and climate variables such as temperature, precipitation, and
light and extreme events and low capacity for adaptation. This article reviews evidence on the scope and nature of the climate
change challenge; and assesses the impact of climate change on agriculture and food security in Sub-Saharan Africa. From the
review, it is apparent that the climate in Africa is already exhibiting significant changes, evident by changes in average
temperature, change in amount of rainfall and patterns and the prevalence of frequency and intensity of weather extremes.
The review also revealed that although uncertainties exist with regards to the magnitude of impacts, climate will negatively
affect agricultural production in Sub-Saharan Africa. Specifically, as result of current and expected climate change, the
area suitable for agriculture, the length of growing seasons and yield potential, particularly along the margins of semi-arid
and arid areas, are expected to decrease. These impacts will affect all components of food security: food availability, food accessibility, food utilisation and food stability and hence increase the risk of hunger in the region. The review thus confirms the general consensus that Sub-Saharan Africa
is the most vulnerable region to climate change. It suggests that, policymakers and development agencies should focus on formulating
and implementing policies and programmes that promote farm level adaptation strategies currently being practiced by farmers
across the region. 相似文献
944.
V. V. Rozhnov E. Yu. Zvychainaya A. N. Kuksin A. D. Poyarkov 《Russian Journal of Ecology》2011,42(6):439-444
Molecular genetic methods were used to perform the species and individual identification of 117 samples of hair and feces
of carnivores collected in natural habitats. The species were identified for 85.5% of the samples. The analysis of the nucleotide
sequences of the cytochrome b mitochondrial gene was used to identify the samples of hair and feces of snow leopards (Uncia uncia, 40%), red foxes (Vulpes vulpes, 48%), wolves (Canis lupus, 6%), and lynx (Lynx lynx, 5%). The analysis of eight microsatellite loci allowed the genotypes of 13 snow leopards to be described. The sex of 11
animals was identified. 相似文献
945.
M. D. Yevdokimenko 《Russian Journal of Ecology》2011,42(3):205-210
Consideration is given to the results of studies on the postfire dynamics of Transbaikal forests, which are formed under conditions
of highly arid climate and extreme pyrological regime. Data are presented on tree die-off and recruitment in naturally burned
forests and in test stands affected by creeping fires differing in intensity. The hydrothermal regime of soils, precipitation
runoff, and its multifactor models are discussed. It is shown that fires aggravate moisture deficiency on mountain slopes,
impair the productivity of tree stands, and cause their digression. The statistics of forest fires and the risk of lightning
fires are analyzed. 相似文献
946.
The states of the populations of five dominant species of predatory mammals living in the area affected by the Kalinin Nuclear
Power Plant (NPP) and in remote districts of Tver’ oblast have been compared. A total of 1120 skulls, including 708 skulls
from the vicinity of the NPP, have been examined. The data on parameters characterizing similarities between the samples,
the degree and structure of intrapopulation diversity, and ontogenetic stability suggest with a high probability that the
Kalinin NPP has no effect on wild populations of predatory mammals. 相似文献
947.
Soil and biodiversity 总被引:1,自引:0,他引:1
F. Kh. Khaziev 《Russian Journal of Ecology》2011,42(3):199-204
It is shown that the soil diversity-biodiversity system in terrestrial ecosystems operates in spatiotemporal unity, which
manifests itself at different hierarchical levels of their structural-functional organization: successional-evolutionary,
zonal geographic, landscape, biogeocenotic, soil-type, horizon-layer, geochemical, and the levels of elementary soil processes
and soil fertility. Arguments confirming the functional relationship between organisms and soils are considered. Effective
biodiversity conservation is possible on the basis of an ecosystems approach involving simultaneous conservation of soil diversity. 相似文献
948.
A. B. Savinov 《Russian Journal of Ecology》2011,42(3):179-185
According to the basic concept of the theory dealt with in this study, autocenosis, i.e., a self-regulatory host-symbiont system, rather than an individual, is the individual-level unit. Then, democenosis, which is a system of autocenoses, corresponds to the population level. Therefore, natural selection of autocenoses rather
than individuals occurs in a democenosis, and auto- and democenoses, rather than “individuals” and “populations,” are components
of food chains and webs. However, the symbiotic approach does not exclude the population paradigm and will be developed in
parallel with it. 相似文献
949.
950.
The results of studies on the radial increment of larch and pine in central Yakutia are presented. The application of dendroclimatological
methods to the study of tree-ring chronologies has made it possible to evaluate tree growth response to the dynamics of climatic
factors over the past 120 years. The results of analysis of radial tree increment show that the onset of the growing season
has shifted to earlier dates by the end of the 20th century. 相似文献