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81.
82.
By combining the concepts of environmental stress, state susceptibility and environmental crisis, “Security Diagram” (SD) provides a quantitative approach to assessing environmental change and human security. The SD is a tool that clearly presents in a diagram the security situation of a population or region affected by a particular environmental crisis. Its underlying concept emphasises that the higher the level of environmental stress and socio-economic susceptibility, the higher the probability of the occurrence of crisis. Focusing on drought, this study analyses the susceptibility of case study regions in India, Portugal, and Russia from a socio-economic perspective. A conceptual framework of socio-economic susceptibility is developed based on the economic development theories of modernisation and dependency. Fuzzy set theory is used to generate susceptibility indices from a range of national and sub-national indicators, including financial resources, agricultural dependency and infrastructure development (for economic susceptibility), and health condition, educational attainment and gender inequality (for social susceptibility). Results indicate that socio-economic susceptibility over the period 1980–1995 was highest in India, followed by Russia and (since 1989) lowest in Portugal. Globalisation is likely to contribute to changes in the level of socio-economic susceptibility over time. Moreover, specific social and economic structures unique in each country (e.g., the role of women in society in India, the socialist legacy in Russia) may explain differences in susceptibility between the case study regions.
Sabine CampeEmail:
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83.
84.
Adaptation strategies to reduce smallholder farmers’ vulnerability to climate variability and seasonality are needed given the frequency of extreme weather events predicted to increase during the next decades in sub-Saharan Africa, particularly in West Africa. We explored the linkages between selected agricultural adaptation strategies (crop diversity, soil and water conservation, trees on farm, small ruminants, improved crop varieties, fertilizers), food security, farm household characteristics and farm productivity in three contrasting agro-ecological sites in West Africa (Burkina Faso, Ghana and Senegal). Differences in land area per capita and land productivity largely explained the variation in food security across sites. Based on land size and market orientation, four household types were distinguished (subsistence, diversified, extensive, intensified), with contrasting levels of food security and agricultural adaptation strategies. Income increased steadily with land size, and both income and land productivity increased with degree of market orientation. The adoption of agricultural adaptation strategies was widespread, although the intensity of practice varied across household types. Adaptation strategies improve the food security status of some households, but not all. Some strategies had a significant positive impact on land productivity, while others reduced vulnerability resulting in a more stable cash flow throughout the year. Our results show that for different household types, different adaptation strategies may be ‘climate-smart’. The typology developed in this study gives a good entry point to analyse which practices should be targeted to which type of smallholder farmers, and quantifies the effect of adaptation options on household food security. Subsequently, it will be crucial to empower farmers to access, test and modify these adaptation options, if they were to achieve higher levels of food security.  相似文献   
85.
Hydrothermal deep-sea vent fauna is naturally exposed to a peculiar environment enriched in potentially toxic species such as sulphides, heavy metals and natural radionuclides. It is now well established that some of the organisms present in such an environment accumulate metals during their lifespan. Though only few radionuclide measurements are available, it seems likely that hydrothermal vent communities are exposed to high natural radiation doses. Various archived biological samples collected on the East Pacific Rise and the Mid-Atlantic Ridge in 1996, 2001 and 2002 were analysed by ICP-MS in order to determine their uranium contents (238U, 235U and 234U). In addition 210Po–Pb were determined in 2 samples collected in 2002. Vent organisms are characterized by high U, and Po–Pb levels compared to what is generally encountered in organisms from outside hydrothermal vent ecosystems. Though the number of data is low, the results reveal various trends in relation to the site, the location within the mixing zone and/or the organisms' trophic regime.  相似文献   
86.
Rural areas in China suffer from various problems. The stagnating economic development and a lack of (sufficient) job opportunities and basic services, etc., lead to disadvantages for great parts of China's population. In this context, the transport sector plays a crucial role for the development of rural settlements. Although the degree of undersupply varies between villages, the situation of Chinese villages is often worsened by an insufficient developed transport sector. Regarding mobility in rural China, major constraints and therefore challenges are the difficult access to the transport infrastructure, bad road conditions and the lack of public transport systems. Improvements within the transport sector can be regarded as crucial for the economic and social development of (rural) China and should be carried out in a sustainable and holistic manner using participatory approaches. The aim should be the development of mobility strategies considering the specific needs within the field of transport, which shall have a decisive and positive impact on related sectors. This paper is based on experiences made during the 3 years lasting Sino-European research project SUCCESS (Sustainable Users Concept for China Engaging Scientific Scenario) that analyses the present and the potential future role of transport systems in selected rural areas of China. Referring to the case studies of three villages in rural China, some mobility-related projects that present a favourable impact not only on the transport sector but also on the social system and the economy shall be highlighted. Finally, based on the analysis, instruments and measures for the development of a pathway to a sustainable mobility in rural China will be outlined.  相似文献   
87.

Background, aim, and scope  

Lungs are permanently and simultaneously challenged by airborne microorganisms and airborne pollutants. Temporal increase of airborne particulate matter (APM), a potential carrier for extractable organic matter (EOM), degrades the situation of pulmonary patients. The Ah receptor (AhR) has been described as an important factor influencing the immunological challenge by viral infections. Molecular mechanisms underlying epidemiological observations are not well understood. Cytokine secretion (IL-6, IL-8, and TGF-β) from human bronchial epithelial cells (Beas2B) was determined as an indicator for immune responses upon co-stimulation with an artificial analog of viral dsRNA [polyinosinic/polycytidylic acid, (PIC)] and EOM of Standard Reference Material 1649a (SRM). Since polycyclic aromatic hydrocarbons are major components of APM usually acting via the AhR, particular focus was on AhR involvement.  相似文献   
88.
Environmental Science and Pollution Research - Representative sampling of suspended particulate matter is fundamental for assessing river sediment quality, including the distribution and...  相似文献   
89.
In agricultural plant production nitrification inhibitors like 3,4-dimethylpyrazole phosphate (DMPP) are used to retard the microbial nitrification process of fertilized ammonium to enhance the nitrogen supply for cultivated crops and to reduce nitrogen losses from the production system. Besides the well-known ammonia-oxidizing bacteria (AOB) it is known for a few years that also ammonia-oxidizing archaea (AOA) are able to perform the first step in nitrification, hence being also a target for a nitrification inhibitor. However, so far no information are available concerning the effectiveness of DMPP and its extent towards AOB and AOA, neither in bulk soil nor in the root-rhizosphere complex. We investigated in a field experiment performed according to agricultural practice the effect of DMPP on the abundance of AOB and AOA two, four and eight weeks after fertilization. We observed impaired abundances of AOB but not of AOA in both soil compartments that were still visible eight weeks after application, possibly indicating a reduced effectiveness of the nitrification inhibitor in our study.  相似文献   
90.
This paper introduces a series of 11 studies on the relationships between large Western cities (Paris, London, Brussels, Vienna, Barcelona, Athens, New York, Providence) and their surrounding territories over a long historical time period. The concept of hinterland is introduced to designate a rural territory structured by its function of supplying the city with food, fuel, water and other material. The papers question the usefulness of this concept in the current globalized world, where cities are often considered as simple nodes of a network of worldwide trade exchanges, but where new citizen aspirations for reconnecting urban and rural territories are emerging.  相似文献   
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