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31.
Surendra K. Pradhan Helvi Heinonen-Tanski 《Environment, Development and Sustainability》2010,12(5):713-726
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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Sandeep PANDA Nilotpala PRADHAN Umaballav MOHAPATRA Sandeep K. PANDA Swagat S. RATH Danda S. RAO Bansi D. NAYAK Lala B. SUKLA Barada K. MISHRA 《Frontiers of Environmental Science & Engineering》2013,7(2):281-293
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
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Eco-sanitation and its benefits: an experimental demonstration program to raise awareness in central Nepal 总被引:1,自引:0,他引:1
Surendra K. Pradhan Ram Chandra Piya Helvi Heinonen-Tanski 《Environment, Development and Sustainability》2011,13(3):507-518
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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Soil erosion assessment and its correlation with landslide events using remote sensing data and GIS: a case study at Penang Island,Malaysia 总被引:8,自引:0,他引:8
Pradhan B Chaudhari A Adinarayana J Buchroithner MF 《Environmental monitoring and assessment》2012,184(2):715-727
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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Gauri R. Pradhan Antje Engelhardt Carel P. van Schaik Dario Maestripieri 《Behavioral ecology and sociobiology》2006,59(3):333-343
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.
相似文献
Dario MaestripieriEmail: |
40.
Wastewater contains varieties of carbonaceous and nitrogenous compounds that undergo complicated biodegradation processes in wastewater treatment plants. How these different compounds are degraded by activated sludge in aerobic conditions is still a mystery. Researchers have been trying to interpret it using the oxygen uptake rate (OUR) derived from the respirograms of respective substrates. Several models have been proposed to interpret the substrate removal mechanisms using the experimental observations. Have we succeeded in understanding the messages by activated sludge correctly using these models? In this paper, the distinctive nature of the respirograms when activated sludge is fed with different substrates and the biokinetic models that have been developed to explain the substrate removal mechanisms using derived OUR profiles are reviewed. In addition, a sensitivity study was conducted on the recently evolved simultaneous storage and growth model to investigate the influence of key parameters on OUR profiles during the biodegradation process. 相似文献