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31.
This study is based on a visual inspection and a questionnaire survey about sanitation in central Nepal. A total of 201 people from different groups were asked about their knowledge about eco-toilets, the fertilizer value of human urine and wood ash. Farmers were the least educated and least aware of most of the topics asked. Although the majority of educated people were aware about urine fertilizer, 68% of them were not interested in its use in their home, and 39% of them said that it might be not accepted. The visual inspection revealed that environmental hygiene depends on education. It is concluded that farmers need to receive practical demonstrations about the use of eco-toilets and wood ash to appreciate the direct benefits. It can be assumed that since urine fertilizer is a bonus obtained from eco-toilets, this could encourage even poor people to construct these kinds of facilities.  相似文献   
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Bioleaching of a low grade chalcopyrite (ball mill spillage material) was tested for copper recovery in shake flasks. The original samples (as received) were thermally activated (600°C, 30 min) to notice the change in physico-chemical and mineralogical characteristics of the host rock and subsequently its effect on copper recovery. A mixed culture of acidophilic chemolithotrophic bacterial consortium predominantly entailing Acidithiobacillus ferrooxidans strain was used for bioleaching studies and optimization of process parameters of both original and thermally activated samples. Mineralogical characterization studies indicated the presence of chalcopyrite, pyrite in the silicate matrix of the granitic rock. Field emission scanning electron microscopy coupled with Energy dispersive spectroscopy (FESEM-EDS) and X-ray Fluorescence (XRF) analysis indicated mostly SiO2. With pH 2, pulp density 10% w/v, inoculum 10% v/v, temperature 30°C, 150 r·min-1, 49% copper could be recovered in 30 days from the finest particle size (-1+ 0.75 mm) of the original spillage sample. Under similar conditions 95% copper could be recovered from the thermally activated sample with the same size fraction in 10 days. The study revealed that thermal activation leads to volume expansion in the rock with the development of cracks, micro and macro pores on its surface, thereby enabling bacterial solution to penetrate more easily into the body, facilitating enhanced copper dissolution.  相似文献   
33.
This study focuses on awareness and an experimental demonstration about the use of human urine and wood ash as a fertilizer. This study was conducted in Chanauta, central Nepal, from November 2009 to February 2010. The villagers (N = 27) were asked about their awareness of eco-sanitation and fertilizer value of urine and ash. All the participants agreed that the use of urine and ash was a good idea. In the experimental study, the fertilizer value of urine+ash was compared with animal manure and no-fertilizer in the cultivation of radish, potato, broadleaf mustard, cauliflower, and cabbage. Different plants cultivated plots received 54–81 kgN/ha with urine+ash or manure fertilizer. The urine+ash fertilizer produced significantly (p < 0.05) higher broadleaf mustard biomass than obtained from animal manure and without fertilization. Urine+ash-fertilized plots growing radish, potato, cauliflower, and cabbage produced similar or slightly higher yields biomass compared to those achieved with manure fertilization. This might be because of high P, K as well as greater availability of N in applied urine compared to manure. It is concluded that urine+ash fertilizer can be used instead of animal manure; in this study, a dose of 4 L of urine was equal to 1 kg of dry cattle manure and produced a similar or greater yield of vegetable biomass than manure fertilization. To be able to generalize this conclusion, it is important to conduct these kinds of experiments with different seasonal crops and in other parts of the world.  相似文献   
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In this paper, an attempt has been made to assess, prognosis and observe dynamism of soil erosion by universal soil loss equation (USLE) method at Penang Island, Malaysia. Multi-source (map-, space- and ground-based) datasets were used to obtain both static and dynamic factors of USLE, and an integrated analysis was carried out in raster format of GIS. A landslide location map was generated on the basis of image elements interpretation from aerial photos, satellite data and field observations and was used to validate soil erosion intensity in the study area. Further, a statistical-based frequency ratio analysis was carried out in the study area for correlation purposes. The results of the statistical correlation showed a satisfactory agreement between the prepared USLE-based soil erosion map and landslide events/locations, and are directly proportional to each other. Prognosis analysis on soil erosion helps the user agencies/decision makers to design proper conservation planning program to reduce soil erosion. Temporal statistics on soil erosion in these dynamic and rapid developments in Penang Island indicate the co-existence and balance of ecosystem.  相似文献   
36.
Risk of flood-related mortality in Nepal   总被引:1,自引:0,他引:1  
In July 1993, severe flooding devastated Sarlahi district in Nepal. The next month, a follow-up study of a large population cohort was undertaken. The study is unique in that a prospective research database was used to verify residency prior to the flood and to confirm vital status afterwards. It evaluated 41,501 children aged between two and nine years and adults aged 15-70 in 7,252 households. Flood-related fatality rates were 13.3 per 1,000 for girls and 9.4 per 1,000 for boys, 6.1 per 1,000 for women and 4.1 per 1,000 for men. Flood-related fatality rates for children were six times higher than mortality rates in the same villages a year before the flood (relative risk (RR) = 5.9, 95 per cent confidence interval (CI) 5.0-6.8). Flood-related fatality was associated with low socio-economic status preflood (RR = 6.4, 95 per cent CI 2.7-20.0), and having a house constructed of thatch (RR = 5.1, 95 per cent CI 1.7-24.5).  相似文献   
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Female copulation calls are mating-associated vocalizations that occur in some species of Old World monkeys and apes. We argue that copulation calls have two immediate functions: to encourage mating attempts by other males and to increase mate guarding by the consort male. We hypothesize that female copulation calls have evolved under the selective pressures of risk of infanticide and sperm competition. When male mate guarding is effective, copulation calls allow females to concentrate paternity in dominant males and benefit from their protection against the risk of infanticide. When mate guarding is ineffective, copulation calls may bring genetic benefits to females through facilitation of sperm competition. We present a quantitative model in which interspecific variation in females' promiscuity predicts their tendency to use copulation calls in conjunction with mating. The model predicts that in species with little female promiscuity, copulation calls should be rare and exhibited only in association with mating with dominant males. In species in which females are highly promiscuous, copulation calls should be frequent and unrelated to male dominance rank. The limited data available to test the model support its main predictions as well as the predicted relation between copulation calls and male dominance rank.
Dario MaestripieriEmail:
  相似文献   
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In this study, landslide risk assessment for Izmir city (west Turkey) was carried out, and the environmental effects of landslides on further urban development were evaluated using geographical information systems and remote sensing techniques. For this purpose, two different data groups, namely conditioning and triggering data, were produced. With the help of conditioning data such as lithology, slope gradient, slope aspect, distance from roads, distance from faults and distance from drainage lines, a landslide susceptibility model was constructed by using logistic regression modelling approach. The accuracy assessment of the susceptibility map was carried out by the area under curvature (AUC) approach, and a 0.810 AUC value was obtained. This value shows that the map obtained is successful. Due to the fact that the study area is located in an active seismic region, earthquake data were considered as primary triggering factor contributing to landslide occurrence. In addition to this, precipitation data were also taken into account as a secondary triggering factor. Considering the susceptibility data and triggering factors, a landslide hazard index was obtained. Furthermore, using the Aster data, a land-cover map was produced with an overall kappa value of 0.94. From this map, settlement areas were extracted, and these extracted data were assessed as elements at risk in the study area. Next, a vulnerability index was created by using these data. Finally, the hazard index and the vulnerability index were combined, and a landslide risk map for Izmir city was obtained. Based on this final risk map, it was observed that especially south and north parts of the Izmir Bay, where urbanization is dense, are threatened to future landsliding. This result can be used for preliminary land use planning by local governmental authorities.  相似文献   
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