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61.
Small farmers who supply the city of Bogotá with food are facing many challenges that are jeopardizing their livelihoods and by extension, the food security of Colombia’s capital. We expect future changes in climatic conditions to exacerbate the plight of the small farmers and this is expected to compromise Bogota’s food security even further. This paper specifically seeks to assess the impact of climate change (CC) on the livelihoods of smallholders who supply Bogota with most of its food. In our multidisciplinary methodology, we translated the exposure to CC into direct impact on crops and assessed sensitivity and adaptive capacity using the sustainable rural livelihoods framework. The results show that rainfall (by average of 100 mm) and temperature (by average of 2.1 °C) will increase over the study area, while the future climate suitability of the most important crops such as mango (Mangifera indica), papaya (Carica papaya), corn (Zea mays) and plantain (Musa balbisiana) shows a decrease of 19 % to 47 % climate suitability by the year 2050. The assessment of sensitivity and adaptive capacity demonstrates that farmers participating in a farmers’ market, initiated by several local and international non-governmental organizations (NGOs), are less vulnerable to CC than farmers who sell through intermediaries. Those farmers selling directly to consumers in the farmers’ market have a higher adaptive capacity (3 on a scale of 3) in social and financial capital than those selling to intermediaries with less adaptive capacity (1 on a scale of 3). In light of the reduction in overall climatic suitability of some of the major crops and the change of geographic location of suitability for others, there are likely to be serious threats for Bogotá’s food security, the ecological landscape around the city, and farmers’ livelihoods. We further conclude that unless proper adaptation measures are implemented, the geographical shift in climate suitability may also force farmers to shift their crops to higher elevations including remaining forests and páramos (the Colombian alpine tundra ecosystems), which may be threatened in the near future.  相似文献   
62.
The crayfish play an essential role in the biomonitoring and may reflect ambient water quality through the biochemical, behavioural and physiological reactions. To assess whether narrow-clawed crayfish Astacus leptodactylus can respond by heart rate changes to presence in water of such biocide as chloramine-T, adult males were exposed to its low (2 and 5 mg L?1), moderate (10 mg L?1, commonly used in industry and aquaculture) and exceeded (20 and 50 mg L?1) concentrations. In addition, a physical stress test evaluated energy expenditure following the chemical trials. Three key reactions (cardiac initial, first-hour and daily prolonged exposure) were discussed with particular focus on crayfish initial reaction as the most meaningful in on-line water quality biomonitoring. After short-term exposure to both chloramine-T concentrations, crayfish were found to respond rapidly, within 2–5 min. According to heart rate changes, the 1-h exposure did not adversely affect crayfish at either concentration, as well as during daily exposure to 10 mg L?1. As assessed by the heart rate, the 24-h exposure to 50 mg L?1 of chloramine-T was toxic for crayfish and led to substantial loss of energy that became apparent during subsequently conducted physical stress. The results supported a hypothesis that crayfish vital functions are connected with environment they inhabit closely enough to serve as biological monitors. Crayfish were tolerant to short-term chloramine-T exposure, while rapid crayfish reaction to an increased chemical level indicated their high sensitivity, an essential attribute of real-time environmental assessment.  相似文献   
63.
Levels of 2,3,7,8-TCDD were measured in more than one hundred soil samples collected around a TCP-producing plant. Some other materials were also tested. A suitable method for determination of 2,3,7,8-TCDD in heavy contaminated soils was developed. The levels obtained are presented.  相似文献   
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The paper differentiates approaches in technology (end-of-pipe, cleaner production, industrial ecology, zero emission and eco-social-tech) and compares them in respect to the problem solving capacity on the ecological as well as social dimension by showing the eco-impact reduction and job creation. Eco-social-tech represents the approach with highest problem solution as it is based on "eco-social market economy", which will the replace free market economy. The deep background of these innovations is "ecosophy", the wisdom of nature, which serves as guideline for eco-restructuring the world.  相似文献   
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The paper explores the impact and sustainability of environmental assistance coming to Russia from EU-based public and private foundations, and its implications for environmental governance. Geographically, the study ’encompassed all the assistance projects awarded in 1991–2016 involving beneficiaries from Pskovskaya Oblast’. This region is potentially an important target for EU investments in environmental infrastructure, due to its location by the EU border and high value of natural capital. The study demonstrates how the assumptions offered by the international aid literature (mostly derived from the global South) apply to Russia. We found major limitations to the assumption that co-financing provided by recipients ensures project effectiveness (demonstrating the acceptance of the donor's agenda) or sustainability (providing interest to the maintenance of outputs). Tangible assets are normally co-financed only if the investment was in agenda anyway (and therefore the donor gets only time gains, although this can be a valid purpose too); soft outputs (plans, surveys, policies, etc.) are usually co-financed in-kind, and therefore cannot secure any additional commitment. Likewise, physical infrastructure often ends up mismanaged due to low or no maintenance budgets available, while maintenance of soft outputs is too much dependent on contextual factors beyond the co-finance paradigm.  相似文献   
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The Science of Nature -  相似文献   
70.
Large-scale effects of diffuse heavy metals pollution on terrestrial ecosystems are still underestimated. We studied the relation between the biodiversity of vascular plants and the feeding Lepidoptera, in our case leaf-miners and pollinating adult butterflies, in a Dutch nature reserve over a period of five years. We found that 5% of the 56 plants species which provide food and habitat to Microlepidoptera during their larval stage were affected by heavy metal pollution. Furthermore, the numerical abundance of leaf-mining larvae remained rather constant, despite of significant increases of the concentrations of Cd, Cu, Ni and Zn pollutants in leaves and litter.  相似文献   
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