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1.
The distribution of chemical elements in plants was studied in natural and technogenic ecosystems of the southern Baikal region. Basic statistical parameters characterizing the contents of a wide range of elements in different soil horizons and plants of the region and the “world land” (average for all the continents) were compared. On the basis of data on the distribution of chemical elements in the soil-plant system, groups of elements differing in the coeffient of biological absorption (C b) were distinguished. Evidence of antagonism between the main biophilous elements and heavy metals accumulating in plants was obtained. Interrelations of K and Na, which play an important role in the regulation of osmotic processes in plants, were analyzed. The phenomenon of potassium replacement by sodium in plants of technogenic ecosystems may serve as a criterion for assessing the phytotoxicity and environmental quality.  相似文献   

2.
Human security is linked to people’s access to natural resources and vulnerabilities to environmental change. In the case study of Chilika lagoon, the findings reveal that insecurity linked to natural resources is largely embedded in the historical process of resource allocation among stakeholders, rather than on the presence of resource stocks. The insecurities are strongly tied not only to allocation changes, but also to multiple factors (environmental, technological, and demographic factors). Based on the Chilika lagoon experience, this article develops a pathway toward a clear understanding of the linkage between human security and natural resources in a local context.  相似文献   

3.
The types, frequency, and intensity of human interference with forests markedly affect the vegetation dynamics. Assessment of the impact of anthropogenic disturbances on forest diversity and structure is one of the central issues related to human behaviour and forest ecosystems and management. Both species diversity and density are very sensitive to local anthropogenic disturbance, which can be reduced depending on land-use systems. We used 10 line transects of 500 × 10 m to record and measure all plants ≥10 cm girth in some of the remaining forests surrounding villages in Tripura, Northeast India. To predict the effects of anthropogenic pressure on species richness and forest structure, we recorded and scored all ongoing disturbances in all transects of the forests. Although our study did not show any significant effects on the mean number of species, all diversity indices were significantly affected by disturbance. Total stem density (F = 128.60, p < 0.0001) and basal area (F = 65.30, p < 0.0001) of the forest stands were significantly affected by disturbance. Disturbance significantly (F = 84.81, p < 0.0001) impacts the abundance of mature voluminous trees removed by extensive illegal logging. Further, stem density at the middle (F = 10.01, p < 0.05) and upper (F = 131.70, p < 0.0001) canopy stories was also reduced by high disturbance intensity. The present analysis will be useful to policy-makers and planners for implementation of sustainable forest management at both the local and regional scale.  相似文献   

4.
Within southern Africa, many households are facing increasing pressures as they deal with multiple challenges such as low employment, high levels of disease, environmental resources under pressure and changing political landscapes. To respond to the needs of different individuals and households, it is important to define the nature of their vulnerability. An increasing amount of theoretical and empirical work on the concept of ‘vulnerability’ has led to a range of definitions, indicators and measurement tools, which have come to characterise this field of study. As a result, there is no one general consensus. This paper presents the results from the latest in a series of applied studies conducted since 2004 by a network of scientists working in southern Africa, aimed at refining the definition and application of the concept of vulnerability. The study employed a recently developed multiple-stressor model to guide the collection and analysis of data from three sites in South Africa and Malawi. In this paper, we identify and explore five key ‘symptoms’ of vulnerability emerging from our multi-country data and reflect on the usefulness of the model employed.  相似文献   

5.
Experience in organizing a natural reference area (standard) for studies on the functional dynamics of ecosystems in connection with paludification and forest-bog relationships is described. The essence of studies on ecosystem dynamics with the aid of natural standards and key plots is described using an example of the Yenisei region of Western Siberia. Arguments are presented for the necessity of using a differential approach to studies on the dynamics of nature and taking into account local ecological conditions while extrapolating the results of these studies to other geographic regions.  相似文献   

6.

We examine the dynamics and spatial determinants of land change in India by integrating decadal land cover maps (1985–1995–2005) from a wall-to-wall analysis of Landsat images with spatiotemporal socioeconomic database for ~630,000 villages in India. We reinforce our results through collective evidence from synthesis of 102 case studies that incorporate field knowledge of the causes of land change in India. We focus on cropland–fallow land conversions, and forest area changes (excludes non-forest tree categories including commercial plantations). We show that cropland to fallow conversions are prominently associated with lack of irrigation and capital, male agricultural labor shortage, and fragmentation of land holdings. We find gross forest loss is substantial and increased from ~23,810 km2 (1985–1995) to ~25,770 km2 (1995–2005). The gross forest gain also increased from ~6000 km2 (1985–1995) to ~7440 km2 (1995–2005). Overall, India experienced a net decline in forest by ~18,000 km2 (gross loss–gross gain) consistently during both decades. We show that the major source of forest loss was cropland expansion in areas of low cropland productivity (due to soil degradation and lack of irrigation), followed by industrial development and mining/quarrying activities, and excessive economic dependence of villages on forest resources.

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7.
Relocations of indigenous peoples from protected areas to promote wildlife conservation have typically resulted in negative socioeconomic results for those displaced. The international indigenous peoples’ movement has begun to coalesce around the use of free, prior, and informed consent (FPIC) as a legal mechanism to prevent disadvantageous relocations. In 2006, India’s parliament passed the Forest Rights Act, which requires any village relocation of tribal people be conditional upon their FPIC. I used household surveys and qualitative interviews of relocated and forest (not-yet relocated) villagers from Melghat Tiger Reserve, Maharashtra, to examine (a) the extent to which putatively voluntary relocations were conditional upon FPIC and (b) how such relocations affect socioeconomic metrics and overall quality of life for those relocated. I found that while consent to relocate was mostly free, consent was not fully informed across the villages examined. The socioeconomic results indicate that relocated villagers make a trade-off, leaving a familiar, healthier environment for better access to modern services and employment. Finally, I found that forest villagers in favor of relocation emphasized how the social and economic costs of remaining in the forest had become greater due to the relocation of neighboring villages. This field study suggests that strong implementation of FPIC and state responsiveness post-relocation are both necessary to safeguard forest-dwelling people from disadvantageous relocations.  相似文献   

8.
A cost structure is proposed for optimizing the recirculation and recycling of commodities and energy usage considering regional, national and global operating scales. The methodology proposed involves business administration theory and economics and employs the previously introduced equality principle and the model for efficient use of resources for optimal production economy (EUROPE) to impose shadow costs on unwanted material wastes and energy residuals that produce economic incentives to reduce such wastes at the source. A case study presents the practical application of the proposed theory in a national and a global context. It is concluded that the presented methodology is useful for increasing the cost-effectiveness and optimizing recirculation and recycling in the usage of energy resources and natural resources in general. Profitability increases, technology is advanced and environmental conditions improve simultaneously through the application of the EUROPE model to analyze government policy related to the recirculation and recycling of solid wastes and energy. Furthermore, the equity of the distribution of such recirculation and recycling facilities is improved. The developed methods are useful information support tools for decision-making in the management of energy and other natural resources with emphasis on the economics of recirculated and recycled residuals.  相似文献   

9.
Environment, Development and Sustainability - Groundwater is the major primary source of drinking and irrigation water for nearly 500 million inhabitants in both rural and urban areas of the Ganga...  相似文献   

10.
The contamination of aquatic ecosystems by organic contaminants such as polycyclic aromatic hydrocarbons (PAHs) is a matter of great concern. Mussels have been extensively used as sentinel species in a large number of monitoring programs. However, the use of bivalves as the sole species has some limitations, because they are not as responsive as fish to Aryl Hydrocarbon Receptor agonists. Hence, for many marine areas, there is the need to validate new sentinel fish species that can be used in the assessment of pollution by organic contaminants. The shanny Lipophrys pholis is an intertidal fish that combines many characteristics required in a sentinel species: is abundant and easy to catch, has a wide geographical distribution and restrict home range. After larvae recruitment to the intertidal rocky shores, they remain in the same area for the rest of the life-cycle, thus reflecting local pollutants exposure. In order to evaluate the species sensitivity to organic contaminants under field conditions, L. pholis were collected at six sites reflecting different degrees of anthropogenic contamination. The induction of two biomarkers extensively validated in the assessment of PAHs contamination ethoxyresorufin-O-deethylase activity (EROD) and Fluorescent Aromatic Compounds (FACs) was evaluated. In parallel, mussels were collected at the same locations and levels of 16 PAHs and selected heavy metals determined. Overall, the specimens collected in the urban areas showed a significant induction of EROD and FACs (up to a six-fold induction) if compared with the reference sites. Additionally, a positive correlation was observed between the biomarkers and PAHs levels in mussel tissues. Even though further validation is currently in progress, the available data indicate that L. pholis is responsive to organic contaminants such as PAHs, suggesting its future integration in monitoring programmes designed to evaluate the presence of these contaminants in European marine ecosystems.  相似文献   

11.
On the basis of Annals of Nature of the Prioksko-Terrasnyi Biosphere Reserve, its colonization by invasive mammal species and the current state of their populations have been analyzed. In the mammal fauna of the reserve, 13 out of 60 species can be classified as invasive. They differ in the degree of impact on the biota. The house mouse, Norway and black rats, and European bison have virtually no effect on natural ecosystems; the effect of the muskrat, raccoon dog, American mink, red and axis deer is insignificant; and that of stray dogs and Tartarian roe deer is considerable. The European beaver and wild boar play an environment-forming role. The impact of beaver activities is strong but local, whereas activities of wild boars put into question the very possibility of conservation and analysis of representative biosphere areas and biological diversity in the reserve.  相似文献   

12.
The paper examines the concentrations of isomers of hexachlorocyclohexane (HCHs), dichlorodiphenyl trichloroethane and its metabolites (DDTs), alpha-endosulfan and endosulfan sulfate in surface sediment samples collected from the mouth of Hugli estuary in the vicinity of Sundarban mangrove environment, eastern part of India. An overall pattern of accumulation of these pesticides was in the order of: SigmaHCH>endosulfan sulfate>SigmaDDT>alpha-endosulfan. The concentration of these compounds was quite low. An elevated level of SigmaHCH, SigmaDDT and endosulfan sulfate were marked during premonsoon months, a period characterized by high salinity and pH values. Among the isomers and metabolites of HCH and DDT, beta-HCH, pp'-DDT and pp'-DDE were found to be dominant. The sources of contamination are closely related to human activities, such as domestic and industrial discharges, agricultural chemical applications and soil erosion due to deforestation. The study is compared to other estuarine environment in India and abroad. The present data will serve as a baseline against which future anthropogenic effects may be assessed.  相似文献   

13.
基于正态云模型的区域矿产资源可持续力评价   总被引:1,自引:0,他引:1  
矿产资源是人类生存和社会可持续发展的基础,研究区域矿产资源的可持续力发展水平、能力和发展趋势,不仅仅是个地区问题,更应是资源保障问题,因而对我国资源承载能力和可持续发展具有十分重要的意义。针对当前区域矿产资源可持续力定量测度研究较少,且现有评价方法不能同时兼顾指标的模糊性与随机性的难题,该研究将正态云模型引入区域矿产资源可持续力综合评价。从资源、经济、环境(含人口)三方面构建矿产资源可持续力评价指标体系,基于正态云模型结合改进的层次分析法,不仅使得指标特点得以保真,而且各指标权重的计算量也大大减少,提高了评价方法的适用性。以湖南省2010—2015年间的矿产资源为研究对象,进行矿产资源可持续力定量测度。结果显示,6年间,湖南省矿产资源可持续力状态虽然始终处于III级(一般)状态,但可持续力综合值从2.600 0上升到3.070 8,区域矿产资源可持续力水平有日趋增加态势;个别评价指标仍处于较弱状态,单位GDP能耗量、万元工业产值中矿业产值比率、人口密度单因子得分值均2.5,表明这些指标相对较弱,有待进一步采取相关措施进行改善。该评价结果与实地调研基本吻合,表明该方法是可行的。本方法在定量评价中能兼顾随机性和模糊性,且计算过程简便,结果可靠,能为矿产资源定量评价提供参考。  相似文献   

14.
Mosses are frequently used as biomonitors for trace element pollution in the aquatic environment. The purpose of this study was to assess their usefulness as a tool in monitoring and in regional surveys of radioactive contamination. Specimens of the aquatic mosses, Fontinalis antipyretica and F. dalecarlica, were transplanted from non-contaminated areas to streams and rivers in the Norwegian Jotunheimen Mountains and neighbouring lowland areas that had received radioactive fallout after the Chernobyl accident. Equilibrium concentrations of 137Cs in the exposed mosses were reached after a few weeks. Two series from 20 streams in 1994 and 1996 show linear correlations between activities in water and moss samples and biomagnification ratios of 10(4) - 10(5). We conclude that mosses are better suited for monitoring purposes than water samples, because they provide values integrated over weeks while the radioactivity in surface waters can be subject to rapid variations according to hydrological events. The activity concentrations in aquatic mosses can be easily measured with good precision even when aqueous concentrations are below the limit of detection. Use of aquatic mosses also reduces the logistic problems of transporting large volumes of water, especially in areas inaccessible by road.  相似文献   

15.
Environment, Development and Sustainability - Since 2015, the United Nations sustainable development goals (SDGs) agenda 2030 has been designed with 17 goals, 169 targets, and 232 unique indicators...  相似文献   

16.
17.
新中国成立后,效法前苏联的中国物权立法是一种按照所有权主体分类调整的“身份型”立法,该立法模式不仅抹杀了不同类型国有财产的“个性”,而且也将自然资源的公共性和生态性消融于普通财产的财产属性和独占使用之中。鉴于“公产法定,私产推定”立法模式能够实现自然资源领域政治国家与市民社会之间的利益平衡,并且“公产法定”具有限制国家公权、保障公众对特定自然资源的平等利用权等制度功能,应以国有自然资源资产的分类管理为逻辑主线,重构自然资源国家所有权客体制度:一是明确自然资源为不动产的物权法地位,借助自然资源不动产登记单元和“复杂物”概念对具有特定生态功能的同一自然资源登记单元的不同自然资源的整合功能,将其纳入传统民法物权客体理论的调整之中。二是依据不同自然资源社会属性之强弱,将国有自然资源资产区分为公产和私产,建立分类调整的规则体系,防范公产之上的国家所有权“遁入私法”。三是物权立法应直接明确国有自然资源资产受公法和私法的双重调整,可以公法和私法相互配合的方式行使所有权。四是国家和集体所有之外的资源原则上可自由利用。  相似文献   

18.
Natural radioactive materials under certain conditions can reach hazardous radiological levels. So, it becomes necessary to study the natural radioactivity levels in soil to assess the dose for the population in order to know the health risks and to have a baseline for future changes in the environmental radioactivity due to human activities. The natural radionuclide (226Ra, 232Th, and 40K) contents in soil were determined for 26 locations around the Upper Siwaliks of Kala Amb, Nahan and Morni Hills, Northern India, using high-resolution gamma-ray spectrometric analysis. It was observed that the concentration of natural radionuclides viz., 226Ra, 232Th and 40K, in the soil varies from 28.3 ± 0.5 to 81.0 ± 1.7 Bq kg−1, 61.2 ± 1.3 to 140.3 ± 2.6 Bq kg−1 and 363.4 ± 4.9 to 1002.2 ± 11.2 Bq kg−1 respectively. The total absorbed dose rate calculated from activity concentration of 226Ra, 232Th and 40K ranged from 71.1 to 162.0 nGy h−1. The radium equivalent (Req) and the external hazard index (Hex), which resulted from the natural radionuclides in soil, were also calculated and found to vary from 149.4 to 351.8 Bq kg−1and from 0.40 to 0.95 respectively. These values in Upper Siwaliks area were compared with that from the adjoining areas of Punjab. The radium equivalent activities in all the soil samples were lower than the limit (370 Bq kg−1) set in the Organization for Economic Cooperation and Development (OECD) report and the dose equivalent was within the safe limit of 1 mSv y−1.  相似文献   

19.
Declining crop and livestock production due to a degrading land resource base and changing climate among other biophysical and socio-economic constraints, is increasingly forcing rural households in Zimbabwe and other parts of Southern Africa to rely on common natural resource pools (CNRPs) to supplement their household food and income. Between 2011 and 2013, we combined farmer participatory research approaches, remote sensing and geographic information systems (GIS) to (1) understand the contribution of CNRPs to household food and income in Dendenyore and Ushe smallholder communities in Hwedza District, eastern Zimbabwe and (2) assess changes of the CNRPs in both space and time, and their implications on climate change adaptation. Across study sites, wetlands and woodlands were ranked as the most important CNRPs. Extraction and use patterns of products from the different pools differed among households of different resource endowment. Resource-constrained households (RG3) sold an average of 183 kg household?1 year?1 of wild loquats fruits (Uapaca kirkiana), realising about US$48, while resource-endowed farmers (RG1) had no need to sale any. The RG3 households also realised approximately US$70 household?1 year?1 from sale of crafts made from water reeds (Phragmites mauritianus). Empirical data closely supported communities’ perceptions that CNRPs had declined significantly in recent years compared with two to three decades ago. More than 60 % of the respondents perceived that the availability of natural resources drawn from wetlands and woodlands, often used for food, energy and crafts, has decreased markedly since the 1980s. Classification of land cover in a GIS environment indicated that CNRPs declined between 1972 and 2011, supporting farmers’ perceptions. Overall, woodlands declined by 37 % in both communities, while the total area under wetlands decreased by 29 % in Ushe, a drier area and 49 % in Dendenyore, a relatively humid area. The over-reliance in CNRPs by rural communities could be attributed to continued decline in crop yields linked to increased within-season rainfall variability, and the absence of alternative food and income sources. This suggests limited options for rural communities to adapt to the changing food production systems in the wake of climate change and variability and other challenges such as declining soil fertility. There is therefore a need to design adaptive farm management options that enhance both crop and livestock production in a changing climate as well as identifying other livelihood alternatives outside agriculture to reduce pressure on CNRPs. In addition, promotion of alternative sources of energy such as solar power and biogas among rural communities could reduce the cutting of trees for firewood from woodlands.  相似文献   

20.
Environment, Development and Sustainability - Runoff estimation is of immense importance in hydrological analysis for water resource planning and management. The developing countries cannot afford...  相似文献   

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