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151.
The recent greening of the Sahel region and increase in vegetation cover around pastoral settlements previously described as “man-made deserts”, have raised important questions on the permanency of land degradation associated with the over-exploitation of woody plants. Evidence presented is mostly on increased wetness, while management by local communities has received limited attention. This study evaluated changes in woody vegetation cover around the settlements of Kargi and Korr in northern Kenya, using satellite imagery (1986/2000), ecological ground surveys and interviews with local elders, in order to understand long-term changes in vegetation cover and the role of local community in vegetation dynamics. At both settlements, there were increments in vegetation cover and reduction in the extent of bare ground between 1986 and 2000. At Kargi settlement, there were more tree seedlings in the centre of settlement than further away. Mature tree class was more abundant in the centre of Korr than outside the settlement. The success of the regeneration and recovery of tree cover was attributed to the actions of vegetation management initiative including stringent measures by the local Environmental Management Committees. This study provides good evidence that local partnership is important for sustainable management of resources especially in rural areas where the effectiveness of government initiative is lacking.  相似文献   
152.
This paper compared the life cycle inventory (LCI) obtained from three commercial oil palm biomass composting projects in Malaysia which use the open windrow composting system. The LCI was obtained and calculated based on the functional unit of 1 t of compost produced. The input of the inventory are the feed materials such as empty fruit bunches (EFB) and palm oil mill effluent (POME); and utilities which include electricity generated at palm oil mill and diesel used. Composting 2.0–2.5 t of EFB and 5.0–7.5 t of POME required diesel from 218.7 to 270.2 MJ and electricity from 0 to 6.8 MJ. It is estimated that the composting emitted from 0.01 to 0.02 t CO2eq/tcompost mainly from diesel used to operate machineries. Composting saved 65 % of time required for a complete degradation of POME when compared to ponding system, and 89 % of time required for a complete degradation of EFB compared to mulching. In terms of land required, it required 36 % less land as compared to ponding for POME and 99 % less land as compared to mulching for EFB. Based on the case study, diesel was found to be the main contributor to the environmental impact. There is a potential of upgrading the process to be more economical and environmental friendly. Using electricity as the source of energy has a lower footprint for the composting process. Instead of using raw POME, studies had reported that using treated POME either from anaerobic ponding or digested tank can accelerate the composting process.  相似文献   
153.

Polyethylene laminated disposable paper cups are commonly used as a container for hot drinks, yet there is limited knowledge on the transfer of contaminants from the cup to the drink. Here we poured 95?C hot water in 14 cups, to simulate the preparation of hot beverage for daily use. We studied the water composition after 15 min by inductively coupled plasma mass spectrometry (ICP-MS) and ion chromatography. Results show the presence of metals such as vanadium, chromium, copper, cobalt and arsenic at concentration ranging from 0.04 to 1.80 µg/L. Nitrate, nitrite, chloride, bromate, fluoride and sulfate ions were also detected at concentration from 0.003 to 49.21 mg/L. All concentrations are below the WHO maximum permissible limits in drinking water. However, the levels of vanadium at 1.24 µg/L and fluoride ions at 1.03 mg/L are likely to induce a health risk by bioaccumulation after long-term water ingestion. Therefore paper cups composition should be modified to avoid the release of contaminants in hot drinks.

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154.
Environmental Science and Pollution Research - The bioactivity of nanoparticles has engendered a promise in scientific communities for developing novel therapeutic strategies. This study...  相似文献   
155.
Environmental Science and Pollution Research - Biochar remediation efficiency could be enhanced through numerous treatments such as acids treatment. Still, there has little work done on...  相似文献   
156.
Environmental Science and Pollution Research - PM10 was collected during an EMEP winter campaign of 2017–2018 in two urban background sites in Barcelona (BCN) and Granada (GRA), two...  相似文献   
157.
Environmental Science and Pollution Research - Currently, a well-developed combination of irrigation water quality index (IWQIs) and entropy water quality index (EWQIs) for surface water appraisal...  相似文献   
158.
Environmental Science and Pollution Research - Moroccan employers have a strong responsibility for the safety and health of their employees in the workplace and for protecting them from the risk of...  相似文献   
159.
Environmental Science and Pollution Research - Hydrogen energy, as clean and efficient energy, is considered significant support for the construction of a sustainable society in the face of global...  相似文献   
160.
Journal of Polymers and the Environment - Recently, the advantages of biopolymers over conventional plastic polymers are unprecedented, provided that they are used in situations in which they raise...  相似文献   
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