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71.
Linking Conservation and Development: An Analysis of Local People’s Attitude Towards Koshi Tappu Wildlife Reserve, Nepal 总被引:1,自引:0,他引:1
Ram K. Shrestha Janaki R. R. Alavalapati 《Environment, Development and Sustainability》2006,8(1):69-84
Factors influencing local people’s attitudes towards conservation of the Koshi Tappu Wildlife Reserve (KTWR) are analyzed
using an ordered logit model. The results indicate that households living closer to the KTWR are more likely to reveal negative
attitude towards conservation. Similarly, respondents from larger households tend to show negative conservation attitude.
Educated respondents and farmers are likely to demonstrate a positive conservation attitude. The results consistently show
that households with poor socioeconomic status and greater dependence on the KTWR for firewood, fodder, and raw materials
are likely to possess a more negative attitude towards conservation. Poor households may not necessarily be less concerned
about conservation, although institutional settings and abject poverty near protected areas appear to affect their attitudes.
Sustainable management of protected areas and local support for natural resource conservation would require socioeconomic
development. 相似文献
72.
Soil erosion and the global carbon budget 总被引:62,自引:0,他引:62
Lal R 《Environment international》2003,29(4):437-450
Soil erosion is the most widespread form of soil degradation. Land area globally affected by erosion is 1094 million ha (Mha) by water erosion, of which 751 Mha is severely affected, and 549 Mha by wind erosion, of which 296 Mha is severely affected. Whereas the effects of erosion on productivity and non-point source pollution are widely recognized, those on the C dynamics and attendant emission of greenhouse gases (GHGs) are not. Despite its global significance, erosion-induced carbon (C) emission into the atmosphere remains misunderstood and an unquantified component of the global carbon budget. Soil erosion is a four-stage process involving detachment, breakdown, transport/redistribution and deposition of sediments. The soil organic carbon (SOC) pool is influenced during all four stages. Being a selective process, erosion preferentially removes the light organic fraction of a low density of <1.8 Mg/m(3). A combination of mineralization and C export by erosion causes a severe depletion of the SOC pool on eroded compared with uneroded or slightly eroded soils. In addition, the SOC redistributed over the landscape or deposited in depressional sites may be prone to mineralization because of breakdown of aggregates leading to exposure of hitherto encapsulated C to microbial processes among other reasons. Depending on the delivery ratio or the fraction of the sediment delivered to the river system, gross erosion by water may be 75 billion Mg, of which 15-20 billion Mg are transported by the rivers into the aquatic ecosystems and eventually into the ocean. The amount of total C displaced by erosion on the earth, assuming a delivery ratio of 10% and SOC content of 2-3%, may be 4.0-6.0 Pg/year. With 20% emission due to mineralization of the displaced C, erosion-induced emission may be 0.8-1.2 Pg C/year on the earth. Thus, soil erosion has a strong impact on the global C cycle and this component must be considered while assessing the global C budget. Adoption of conservation-effective measures may reduce the risks of C emission and sequester C in soil and biota. 相似文献
73.
74.
Gypsum has been applied as a natural fertilizer and soil amendment for centuries in agriculture for providing crop nutrients such as Ca and S, and for improving soil physical properties. Recently, gypsum has been tested for sequestrating CO2 from the air and for capturing soluble phosphates in the soil, through formation of insoluble calcium phosphates and carbonates. However, the environmental factors controlling these sequestration processes have not been systemically studied. Here, we calculate optimal conditions of sequestration using chemical equilibrium modeling. Our results show that CO2 carbonation is effective at pH higher than 8.5 at atmospheric concentration. The removal of P is higher than 80 % for pH higher than 6.4, when Ca and P are at stoichiometric ratio. Also, placement of gypsum in subsoil is more effective for CO2 capture than applying it on soil surface since soil pores often contain higher concentrations of CO2 due to the soil respiration process. Overall, increases in medium pH, gypsum application rate, or CO2 partial pressure can increase the effectiveness of the amendment. 相似文献
75.
This paper explores household (HH)-level livelihood dynamics and determinants since construction of the Samanalawewa Hydroelectricity Reservoir (SHER) in the Samanalawewa watershed, Sri Lanka. The research is based on data from a structured questionnaire survey of 201 randomly selected households (HHs) in upstream and downstream areas. Livelihood dynamics at two separate points in time (1988 and 2008) were assessed based on a sustainable livelihood framework (SLF). Impact of livelihood determinants on livelihood was analysed using factor and regression analysis techniques, followed by an optimisation procedure to suggest requirements in selected significant determinants to improve the livelihood of various categories of farm HH. In both upstream and downstream areas, livelihood assets, viz. physical, social and human capital, increased significantly, while access to natural and financial capital decreased significantly and slightly, respectively, during last two decades. The factor analysis extracted six factors in the upstream area and seven in the downstream area. The derived regression models show that nine variables in the upstream area and ten in the downstream area are major determinants of HH livelihood. Based on optimisation results, policy implications are discussed in relation to needed improvements in livelihood determinants to improve overall livelihood of HHs. 相似文献
76.
Zhang Huiying Liu Ruiqiang Ning Tangyuan Lal Rattan 《Environmental Chemistry Letters》2018,16(3):1095-1100
Environmental Chemistry Letters - With rising atmospheric carbon dioxide (CO2) concentrations globally, there is an urgent need for highly efficient CO2 capture technologies. This report introduces... 相似文献
77.
PROBLEM: Fatigue affects a driver's ability to proceed safely. Driver-related fatigue and/or sleepiness are a significant cause of traffic accidents, which makes this an area of great socioeconomic concern. Monitoring physiological signals while driving provides the possibility of detecting and warning of fatigue. The aim of this paper is to describe an EEG-based fatigue countermeasure algorithm and to report its reliability. METHOD: Changes in all major EEG bands during fatigue were used to develop the algorithm for detecting different levels of fatigue. RESULTS: The software was shown to be capable of detecting fatigue accurately in 10 subjects tested. The percentage of time the subjects were detected to be in a fatigue state was significantly different than the alert phase (P<.01). DISCUSSION: This is the first countermeasure software described that has shown to detect fatigue based on EEG changes in all frequency bands. Field research is required to evaluate the fatigue software in order to produce a robust and reliable fatigue countermeasure system. IMPACT ON INDUSTRY: The development of the fatigue countermeasure algorithm forms the basis of a future fatigue countermeasure device. Implementation of electronic devices for fatigue detection is crucial for reducing fatigue-related road accidents and their associated costs. 相似文献
78.
Bir Bahadur Ghale Ganesh Ram Shrestha and Russell J. deLucia 《Natural resources forum》2000,24(4):273-284
This article examines a number of issues connected with the development of small-scale hydroelectric power and related investments in Nepal. The micro-hydro investment scheme in Barpak village serves as a case study, and the article also presents a number of related issues discussed against the background of the evolution of micro-hydro power in Nepal. The article outlines the success of micro-hydro development, modest in relation to its enormous potential, the realization of which depends on whether a number of challenges and constraints can be overcome. The article closes with suggestions on implementing sustainable micro-hydro development in rural areas, based on the Barpak experience and the authors' other recent studies of rural energy issues in Nepal. 相似文献
79.
Climate change in Nepal and its impact on Himalayan glaciers 总被引:2,自引:0,他引:2
Climate change can be particularly hard-hitting for small underdeveloped countries, relying heavily on natural resources for the economy and livelihoods. Nepal is one among these countries, being landlocked, with diverse physiographical characteristics within a relatively small territory and with rugged terrain. Poverty is widespread and the capacity of people and the country to cope with climate change impact is low. The country is dominated by the Asian monsoon system. The main occupation is agriculture, largely based on rain-fed farming practices. Tourism based on high altitude adventures is one of the major sources of income for the country. Nepal has a large hydropower potential. While only 0.75% of the theoretical hydropower potential has been tapped, Nepal can greatly benefit from this natural resource in the future. Climate change can adversely impact upon water resources and other sectors of Nepal. The source of water is mainly summer monsoon precipitation and the melting of the large reserve of snow and glaciers in the Himalayan highlands. Observations show clear evidences of significant warming. The average trend in the country is 0.06°C per year. The warming rates are progressively higher for high elevation locations. The warming climate has resulted in rapid shrinking of majority of glaciers in Nepal. This paper presents state-of-knowledge on the glacial dynamics in the country based on studies conducted in the past in Shorong, Khumbu, Langtang, Dhaulagiri and Kanchenjunga regions of Nepal. We present recent trends in river flow and an overview of studies on expected changes in the hydrological regime due to climate change. Formation, growth and likely outburst of glacial lake are phenomena directly related to climate change and deglaciation. This paper provides a synopsis of past glacial lake outburst floods impacting Nepal. Further, likely impacts of climate change on other sectors such as agriculture, biodiversity, human health and livelihoods are discussed. 相似文献
80.
Fitzgerald EF Shrestha S Palmer PM Wilson LR Belanger EE Gomez MI Cayo MR Hwang SA 《Chemosphere》2011,85(2):225-231
A study was conducted to evaluate the association between PCBs in residential indoor air and in the serum of older, long time residents of three upper Hudson River communities. Samples of indoor air and of serum were collected from 170 persons 55 to 74 years of age, and analyzed for PCBs using glass capillary gas chromatography. After adjusting for age, BMI, cigarette smoking, and Hudson River fish consumption with multiple linear regression analysis, the results indicated statistically significant associations between concentrations in indoor air and serum for PCB-28, a lightly chlorinated congener common in air that accumulates in serum, and PCB-105. Duration of exposure was an important factor, since among persons who had lived in their home for 39 years or more, 11 of the 12 most commonly detected congeners were significantly correlated, as was their sum (∑ PCB). Significant associations between indoor air and serum PCB concentrations also were more likely when collected in cooler months and if the two samples were collected within 20 d of each other. The study is among the first to indicate that PCB concentrations characteristic of residential indoor air are associated with a detectable increase in body burden. 相似文献