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1.
Over 2500 species of invertebrate macrofauna and over 177 species of avifauna live in the forest–tundra of the Lower Ob region and adjacent areas of the northern taiga and shrub tundra. About half of the invertebrate species of the study area are northern—mostly hypo- and hemiarctic—tundra species; the rest are boreal and arctomontane-boreal Holarctic and trans-Palearctic species. The anthophilic and aerobiont insect assemblages include many boreal forest forms. A total of 153 species have been observed nesting at the taiga–foresttundra boundary; 81 species have been observed nesting at the tundra–forest-tundra boundary. The avifauna of the forest–tundra becomes enriched with taiga species in floodplain forests and with tundra species on the flat interfluve, in areas of tundra and tundra-like wetlands. The forest–tundra of the Lower Ob region has no avifauna and entomofauna of its own and contains a mixture of taiga and tundra faunas. It has been found that the ecotone effect is not pronounced in the taxonomic composition of birds and insects in the forest–tundra, where only some particular groups (such as amphibiont insects) have increased abundance.  相似文献   

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Fars has a special place in Iran in terms of natural resources and diverse climate aiming this province to increase production of major crops such as corns. In light of increasing domestic production and preventing yield loss of maize, many farmers utilize high quantities of pesticides, chemical fertilizers and over-extract groundwater without considering immediate and long-term consequences of such operations on environment. The main purpose of this study is to investigate technical efficiency and sustainability–technology gap ratio (STGR) of maize producers by agricultural sustainability in Fars province in Iran. Technical efficiency is considered as a key element among the triple elements of sustainable development (economic, social and ecological). Applying model of agricultural sustainability and compromise programming method, regions were classified into three groups (sustainable, relatively sustainable and unsustainable), and data were collected interviewing a total of 300 farmers in 2008–2009 from Kazerun, Firouzabad and Marvdasht chosen randomly and systematically as representatives of these three groups. Technical efficiencies and STGRs were calculated for the regions applying stochastic production frontier, regional stochastic frontier functions and the metafrontier. The results indicate that assuming the same technology between the fields (traditional methods) leads to overestimation of technical efficiency. Mean STGRs in Marvdasht, Firouzabad and Kazerun were found to be 59.3, 71.1 and 68.9, respectively. This suggests that technical efficiency and STGR of relatively sustainable regions are higher than those of the unsustainable regions. Thus, farmers in these areas can reduce gap between technology and agricultural sustainability levels via achieving metatechnology that is compatible with sustainable agriculture.  相似文献   

4.
The horizontal distribution and quantitative characteristics of macrozoobenthos were studied in small lakes of the Darwin Nature Reserve (southern Vologda oblast). The aggregation index varied in the open areas of acid lakes, which indicated that communities of small acid water bodies were unstable. The aggregation was the lowest in the open area of a neutral lake. In acid lakes, the number and biomass of macroinvertebrates were the highest near the coasts. In the neutral lake, conversely, these values were maximum in open areas and low near the coast due to a strong pressure of predatory invertebrates and fish. An aggregating effect of invertebrate predators was observed near the coasts of lakes of different types.  相似文献   

5.
Rural–urban land conversion is an inevitable phenome non in urbanization and industrialization. And the decision-making issue about this conversion is multiobjective because the socia decision maker (the whole of central government and local author ity) has to integrate the requirements of different interest groups (rural collective economic organizations, peasants, urban land us ers and the ones affected indirectly) and harmonize the sub-objects (economic, social and ecological outcomes) of this land alloc...  相似文献   

6.
The associations of 8 pesticides and pesticide metabolites with total diabetes (diagnosed and undiagnosed) and pre-diabetes (glycohemoglobin 5.7–6.4%) were evaluated using the National Health and Nutrition Examination Survey (NHANES), 1999–2004. Six of the pesticides were found to be associated with total diabetes in separate adjusted logistic regressions. These pesticides and pesticide metabolites were beta-hexachlorocyclohexane, p,p′-DDE, p,p′-DDT, oxychlordane, trans-nonachlor, and heptachlor epoxide. When the number of compounds elevated was tested, 4 or more, of the 6, elevated had an odds ratio of 4.99 (95% CI 1.97–12.61) compared to none elevated. When the 6 compounds were tested together in a single combined adjusted logistic regression only oxychlordane, a metabolite of chlordane, and heptachlor epoxide, a metabolite of heptachlor, were significantly associated with total diabetes. In the combined adjusted logistic regression, oxychlordane ≥ 14.5 ng/g lipid adjusted had an odds ratios of 1.90 (95% CI 1.09–3.32) compared to oxychlordane < 14.5 ng/g lipid adjusted, and heptachlor epoxide ≥ 14.6 ng/g lipid adjusted had an odds ratio of 1.70 (95% CI 1.16–2.49) compared to heptachlor epoxide < 14.6 ng/g lipid adjusted. Heptachlor epoxide and p,p′-DDT were significantly associated with pre-diabetes in separate adjusted logistic regressions. When these 2 compounds were tested together only heptachlor epoxide remained significantly associated with pre-diabetes. The evidence supporting the relationship between pesticides and pesticide metabolites, with diabetes, was strongest for heptachlor epoxide and oxychlordane, intermediate for p,p′-DDT, and least for beta-hexachlorocyclohexane, p,p′-DDE, and trans-nonachlor. Mirex and dieldrin were not associated with total diabetes or pre-diabetes.  相似文献   

7.
Abstract

Rural–urban land conversion is an inevitable phenomenon in urbanization and industrialization. And the decision-making issue about this conversion is multi-objective because the social decision maker (the whole of central government and local authority) has to integrate the requirements of different interest groups (rural collective economic organizations, peasants, urban land users and the ones affected indirectly) and harmonize the sub-objects (economic, social and ecological outcomes) of this land allocation process. This paper established a multi-objective programming model for rural–urban land conversion decision-making and made some social welfare analysis correspondingly. Result shows that the general object of rural–urban land conversion decision-making is to reach the optimal level of social welfare in a certain state of resources allocation, while the preference of social decision makers and the value judgment of interest groups are two crucial factors which determine the realization of the rural–urban land conversion decision-making objects.  相似文献   

8.
Ecological and phytocenotic features of forest communities were studied in the southwest of Moscow oblast. Based on the ecomorphological groups of species prevalent in the herb–dwarf shrub and moss layers, five groups of communities typical of the conifer–broadleaf forest zone were distinguished (small-herb, small herb-large herb, large-herb, moist-herb, and mixed-herb communities), and their composition was analyzed. Discriminant analysis of the species composition of lower vegetation layers revealed significant differences between the syntaxa, with the percentage of correct classification being 89.8%. To evaluate ecological determination of the above groups of communities, a hypothesis was tested concerning the correlation of their composition with ecotope properties. This hypothesis was verified by means of (1) ordination by ecological indicator values and interpretation of the axes, (2) revealing differences in ecological regimes between habitats of the syntaxa, and (3) combined analysis of on-ground and remote sensing data, particularly spectral brightness of satellite images and morphometric characteristics of the terrain surface. The results confirmed the informativeness of the syntaxa distinguished based on the species composition of the ground vegetation layer and mapping of the ecological regimes of habitats.  相似文献   

9.
The spatial and temporal distributions of the anthropogenic radionuclides 137Cs and 90Sr, originating from nuclear bomb testing, the Sellafield reprocessing plant in the Irish Sea (UK), and from the Ob and Yenisey river discharges to the Arctic Ocean, have been simulated using the global version of the Miami Isopycnic Coordinate Ocean Model (MICOM). The physical model is forced with daily atmospheric re-analysis fields for the period of 1948–1999. Comparison of the temporal evolution of the observed and the simulated concentrations of 90Sr has been performed in the Kara Sea. The relative contributions of the different sources on the temporal and spatial distributions of the surface 90Sr are quantified over the simulated period. It follows that the Ob river discharge dominated the surface 90Sr over most of the Arctic Ocean and along the eastern and western coasts of Greenland before 1960. During the period of 1980–1990, the atmospheric fallout and the Ob river discharge were equally important for the 90Sr distribution in the Arctic Ocean. Furthermore, an attempt has been made to explore the possible dispersion of accidental released 90Sr from the Ob and Yenisey rivers under a global warming scenario (2 × CO2). The difference between the present-day and the global warming scenario runs indicates that more of the released 90Sr from the Ob and Yenisey rivers is confined to the Arctic Ocean in the global warming run, particularly in the near coastal, non-European part of the Arctic Ocean.  相似文献   

10.
Abstract

Water pollution is one of the major environmental problems, especially in urban areas. Due to rapid urban expansion and industrialization, water pollution in Zhengzhou City, the capital of Henan Province in central China has become a serious problem for its development. In this study, the surface water quality was evaluated using Nemerow Comprehensive Pollution Index (NCPI), and the change trend was calculated using methods of Mann-Kendall test and Sen’s slope estimator, based on the monitoring data from 1998 to 2008. The results show that the NCPI ranged from 3 to 50 in 70% of the monitoring cases, implying that most rivers were seriously polluted. However, this serious polltuon is expected to be gradually improved, as the concentration of water pollutants and NCPI declined significantly in most rivers. Water pollution in reservoirs was much lower than rivers, and the NCPI in the three monitored reservoirs was lower than 3 in most years, and shows a downward trend. Although the surface water quality was gradually improved, great efforts are still needed to enhance the protection and improvement of surface water environment.  相似文献   

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Land use and land cover change (LUCC) has emerged as an important issue of global change with significant influences on the geochemical cycle and regional climate change. Understanding the historical changes of land use and analyzing the environmental effects of LUCC make such reconstructions important. Based on historical statistics, this article reconstructs cropland area at the municipality level (härad/kommun) in the Scandinavian Peninsula during 1875–1999. The total acreage of cropland increased 36.84 % during 1875–1930, kept stable during 1930–1950, and decreased 14.25 % during 1950–1999. The croplands of Sweden and Norway both increased before 1950 and changed in different ways during 1950–1999 when the cropland decreased by 19.79 % in Sweden but increased by 9.63 % in Norway. The counties in the south Scandinavian Peninsula owned most of the cropland, with a cropland proportion of over 20 %, and experienced relatively obvious cropland changes. Growth centers with a rate of increase of over 5 % during 1875–1910 were found in Skåne, Stockholm, the Uppsala counties in Sweden, and the area around Oslo county in Norway. The general cropland distribution showed almost no change during this period, which mainly reflects the suitability of the natural conditions for agriculture. Multi-social factors co-impacted land use activities and induced temporal and spatial variations of the cropland. These factors included food supply, world trade, wars, agriculture policies, the economic and political environment, urbanization, and national differences. Compared with the widely used global land use dataset Historical Database of the Global Environment (HYDE), this study shows different cropland change curves before 1950. This article is a case study showing that the hindcasting model of the HYDE dataset has difficulty estimating multi-determined cropland change in the Scandinavian Peninsula, and the empirical study contributes to the improvement of the accuracy of historical land use data at the regional level.  相似文献   

13.
Human–elephant conflict is an issue of great concern regarding the growing competition between people and wildlife for food and shelter throughout Asia and Africa. The situation the Asian elephant faces is much critical. According to IUCN (Big hopes for endangered Asian Elephants, News Release, Gland, 2006), one of the prime factors to the decline of elephant population in India is the increasing trend in human–elephant conflict. Barjora block of Bankura district in West Bengal is one of the severe conflict prone zones in West Bengal, where elephant raid in every year has now become an inevitable phenomenon. As a result, crop damage, infrastructural damages, disturbances of daily activities, occurrence of human death and injuries have no doubt annihilated and frustrated the social fabric of life. This paper is an empirical attempt to address various consequences of human–elephant encounters which have an adverse impact on social, economic as well as the cultural life of the people. Instead of pursuing some traditional mitigation techniques, we argued much on understanding peoples’ perception to explore some sustainable mitigation measures to ensure the interest of both human and elephant and also to safeguard ecological integrity.  相似文献   

14.
ObjectiveA recent longitudinal study reported an association between fine particulate (PM2.5) exposure and preterm birth (PTB) in a US cohort. We applied the same design to an Australian cohort to investigate associations with PTB and pre-labor rupture of membranes (PROM).MethodsFrom 287,680 births, we selected 39,189 women who had singleton births at least twice in Western Australia in 1997–2007 (n = 86,844 births). Analyses matched pregnancies to the same women with conditional logistic regression.ResultsFor PROM adjusted odds ratios (ORs) for a 1 μg/m3 increase in PM2.5 in the first trimester, second trimester, third trimester, and whole pregnancy were 1.00 (95% confidence interval (CI): 0.97, 1.03), 1.03 (95% CI: 1.00, 1.06), 1.02 (95% CI: 1.00, 1.05), and 1.02 (95% CI: 0.99, 1.05) respectively. For PTB, corresponding ORs were 1.00 (95% CI: 0.96, 1.04), 1.00 (95% CI: 0.96, 1.04), 0.98 (95% CI: 0.94, 1.02), and 0.99 (95% CI: 0.95, 1.04) respectively.ConclusionRisk of PROM was greater for pregnancies with elevated PM2.5 exposure in the second trimester than were other pregnancies to the same Australian women at lower exposure. There was insufficient evidence for an association with PTB, indicating that a longer time period might be needed to observe an association if a causal effect exists.  相似文献   

15.
Policy-making in social-ecological systems increasingly looks to iterative, evolutionary approaches that can address the inherent complexity of interactions between human wellbeing, provision of goods, and the maintenance of ecosystem services. Here, we show how the analysis of available time-series in tropical delta regions over past decades can provide important insight into the social-ecological system dynamics in deltaic regions. The paper provides an exploratory analysis of the recent changes that have occurred in the major elements of three tropical deltaic social-ecological systems, such as demography, economy, health, climate, food, and water. Time-series data from official statistics, monitoring programmes, and Earth observation data are analysed to explore possible trends, slow and fast variables, and observed drivers of change in the Amazon, Ganges–Brahmaputra–Meghna and Mekong deltas. In the Ganges–Brahmaputra–Meghna delta zone, increasing gross domestic product and per capita income levels since the 1980s mirror rising levels of food and inland fish production. In contrast, non-food ecosystem services, such as water availability, water quality, and land stability appear to be deteriorating. In the Amazon delta, natural and anthropogenic perturbations are continuously degrading key ecosystem services, such as carbon storage in biomass and soils, the regulation of water balance, and the modulation of regional climate patterns. In the Mekong delta, rapid economic development, changing land-use practices, and salinity intrusion are progressively putting more pressure on the delivery of important provisioning services, such as rice and inland aquaculture production, which are key sources of staple food, farm incomes, and export revenue. Observed changes in many key indicators of ecosystem services point to a changing dynamic state and increased probability of systemic threshold transformations in the near future.  相似文献   

16.
Analyses of ecological regime shifts primarily focus on abrupt, long-term and significant changes that trigger fundamental reorganisation in ecosystem structure and function. There remains limited empirical work on the relationship between regime shifts and social inequities, power imbalances, and social and environmental injustices. Inadequate attention to this social context restricts our ability to predict and avert impending regime shifts, or to effectively navigate where thresholds have been crossed. In this paper, we offer an initial empirical assessment of politics and power in two coastal lagoons in India and Vietnam experiencing abrupt change. We adopt a realist view of power to: (1) assess the social relations structuring human–environment interactions in both lagoons; (2) characterise the dominant framings and narratives that influence if and how regime shifts are understood; (3) consider who wins and loses if and when regime shifts and other forms of rapid environmental change take place; and (4) reflect on the implications of power and politics for the governance of regime shifts in linked human–ocean settings.  相似文献   

17.
Tropical delta regions are at risk of multiple threats including relative sea level rise and human alterations, making them more and more vulnerable to extreme floods, storms, surges, salinity intrusion, and other hazards which could also increase in magnitude and frequency with a changing climate. Given the environmental vulnerability of tropical deltas, understanding the interlinkages between population dynamics and environmental change in these regions is crucial for ensuring efficient policy planning and progress toward social and ecological sustainability. Here, we provide an overview of population trends and dynamics in the Ganges–Brahmaputra, Mekong and Amazon deltas. Using multiple data sources, including census data and Demographic and Health Surveys, a discussion regarding the components of population change is undertaken in the context of environmental factors affecting the demographic landscape of the three delta regions. We find that the demographic trends in all cases are broadly reflective of national trends, although important differences exist within and across the study areas. Moreover, all three delta regions have been experiencing shifts in population structures resulting in aging populations, the latter being most rapid in the Mekong delta. The environmental impacts on the different components of population change are important, and more extensive research is required to effectively quantify the underlying relationships. The paper concludes by discussing selected policy implications in the context of sustainable development of delta regions and beyond.  相似文献   

18.
The paper explores the concept of ‘sustainable place-making’ and its necessary relationships and opportunities with the emerging, broader and interdisciplinary field of sustainability science. This implies a reconsideration of the new and emerging interrelationships between economy, community and ecology as a basis for active place-making. The paper then examines the new dynamics of place-making with regard to the contested emergence of the bio-economy and the eco-economy, and the principles and place framings that lie behind these competing paradigms of spatial development. The reference point here is agri-food and urban–rural relations; and it is argued that research in these fields is in need of being contextualised critically and normatively within this dynamic, highly contested and place-making context. The analysis also holds important implications for a more critical and engaging sustainability science.  相似文献   

19.
Russian Journal of Ecology - To assess carbon dioxide exchange in the ecosystem of cowberry–lichen pine forest, 8790 eddy covariance measurements were made during the summer–autumn...  相似文献   

20.
Regional Environmental Change - African land systems play a decisive role in addressing future sustainability challenges for food and energy supply—in Africa and potentially elsewhere....  相似文献   

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