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71.
Samantha Jones 《Geoforum》2007,38(3):558-575
In the buffer zone of the Royal Chitwan National Park (RCNP), community forests represent a key land use to meet the objectives of the buffer zone concept. This article examines three diverse community forests surrounding the national park and explores how national policy has been mediated by emerging community forestry institutions to create different levels of resource access and benefit distribution both within and between local user groups. Mindful of recent critiques of community-based conservation, the analysis gives considerable attention to the dynamics of power relations and inequality. The extent to which property rights have been transferred to the local level is evaluated and to whom power has been devolved in the process is assessed. The distribution of benefits arising from community forestry is critically examined. It seems that the current system for community forestry creates sufficient incentives for local cooperation due to the potential for increased access to important resources and a high perception of ownership of community forests among the communities. However, emerging institutions vary in the extent to which they reproduce favourable resource access conditions for elites and benefit distribution does seem to be skewed in favour of the wealthy and higher castes, even where management practices on the surface appear fair. National policy creates sufficient but not necessary conditions for achieving downward accountability, transparency and fairness. Greater attention to these issues is needed for buffer zone community forestry to better serve the poor and marginalised populations within user groups.  相似文献   
72.
Participatory ecological monitoring brings together conservationists and members of the public to collect data about changes in nature. This article scrutinizes the “social nature” of such monitoring, considering not only its impacts for nature, but also society, and importantly the ways in which these interact. Drawing on the field of nature–society studies we present a framework with which to explore case studies from the community forests of Nepal. We document the importance of multiple knowledges of nature, including what is referred to as “local monitoring” and its relation to the scientific procedures promoted in participatory monitoring; the consequences of participatory monitoring as a situated and embodied practice, such that it may (re)produce social inequalities; and the place of monitoring within the wider socioecological regime, with regard to possible unintended consequences for both nature and society. This article thus expands our understanding of the complexities of this increasingly popular approach to conservation.  相似文献   
73.
To enable more effective monitoring of sustainable development for meeting targets of the post-2015 agenda, assessment is required at the sub-national level to better understand the spatial variation in factors which contribute to sustaining livelihoods. In this research we take Nepal as a case study; a nation consistently ranked as one of the poorest in the world. To understand how sustainable development can effectively promote livelihood diversification, we advocate that a multidimensional spatial approach is essential for monitoring social and environmental change to aid decision-making processes. To achieve this, a multidimensional index was created to spatially explore the landscape of livelihoods across rural Nepal. A methodology was developed to quantify the livelihoods asset pentagon (human-physical-social-financial-natural) of the Sustainable Livelihoods Framework. 23 socio-environmental indicators were selected to map the multidimensionality of livelihoods at the eco-development area unit level and produce the Multidimensional Livelihoods Index (MLI). Results indicate considerable spatial variability in the factors affecting people's livelihoods across Nepal. In general, the MLI decreases as you move north and east, reflecting changes in the topographic landscape and distance from the Kathmandu Valley Outcomes suggest an effective method for monitoring change at a sub-national level; highlighting potential locations and/or livelihood strategies for improving the targeting of resources (e.g. investment of foreign aid) to facilitate more sustainable development for the future.  相似文献   
74.
Abstract

This study presents the first comprehensive nationwide trend detection of streamflow in Nepal, a country that has been historically understudied despite its critical location as the southern pathway for most of the Himalayan snowpack melt and torrential seasonal monsoon rains. We applied Mann-Kendall and Sen's trend tests using trend-free pre-whitening and bootstrap approaches to two streamflow data sets to deal with serial and cross-correlation. The two data sets comprised 23–33 hydrometric stations with 31 years and more than 20 years of published data, respectively. The test on the 33 stations data set showed that 23% of the streamflow variables studied had statistically significant trends, evenly divided between upward and downward trends. Similarly, in the second, relatively smaller data set, 24% of variables exhibited trends, of which 41% were downward and 59% upward. The higher percentage of observed upward trends in pre-monsoon and winter seasonal average flow is noteworthy given the potential snowmelt contribution in many of the studied sites. Trends were mostly absent in stations draining the larger basins. However, some spatial patterns were seen in the observed trend directions, specifically, a downward trend in the Karnali-Mahakali River basin and an upward trend in the West Rapti River basin, as well as a nationwide absence of trend in the post-monsoon season.

Editor Z.W. Kundzewicz

Citation Gautam, M.R. and Acharya, K., 2011. Streamflow trends in Nepal. Hydrological Sciences Journal, 57 (2), 344–357.  相似文献   
75.
Abstract

A simple guide (shown in the appendix) is produced, which enables a water manager or engineer to make an estimate of statistics of water equivalent of snow cover for return periods between 5 and 100 years for most places in the United Kingdom. This paper describes how the guide was produced using many different sources of data. The methods described here will be of help to both meteorologists and hydrologists in temperate countries with similar snow questions.  相似文献   
76.
Probabilistic seismic hazard analysis in Nepal   总被引:3,自引:0,他引:3  
The seismic ground motion hazard for Nepal has been estimated using a probabilistic approach. A catalogue of earthquakes has been compiled for Nepal and the surrounding region (latitude 26% N and 31.7% N and longitude 79° E and 90° E) from 1255 to 2011. The distribution of catalogued earthquakes, together with available geological and tectonic information were used to delineate twenty-three seismic source seismic source information and probabilistic earthquake hazard prediction relationship, peak ground accelerations (PGAs) have zones in Nepal and the surrounding region. By using the parameters in conjunction with a selected ground motion been calculated at bedrock level with 63%, 10%, and 2% probability of exceedance in 50 years. The estimated PGA values are in the range of 0.07-0.16 g, 0.21 0.62 g, and 0.38-1.1 g for 63%, 10%, and 2% probability of exceedance in 50 years, respectively. The resulting ground motion maps show different characteristics of PGA distribution, i.e., high hazard in the far-western and eastern sections, and low hazard in southern Nepal. The quantified PGA values at bedrock level provide information for microzonation studies in different parts of the country.  相似文献   
77.
Tourism is Nepal's largest industry, giving people in rural areas an alternative to subsistence farming. Tourism can have an impact on the forest cover of a region as trees provide firewood for cooking and heating and timber for building accommodation. In 1986 the Annapurna Conservation Area Project was established to ensure that tourism was managed more sustainably, which includes minimising its impact on the forest cover. This study assesses the impacts of tourism on the forest cover in the Annapurna region by comparing Landsat images from 1999 to 2011. This was achieved through spectral classification of different land cover and by assessing the change in forest cover in relation to increasing distances from tourism villages. A major problem with remote sensing in mountainous regions such as Nepal is shadow caused by the relief. This issue was addressed by only assessing areas which were free from shadow, which in effect meant a sample was used rather than the whole study region. The results indicate that there has been an 8 percent reduction in overall forest extent, but this change varies by region. In the northern, drier regions there has been a net increase in forest cover, while in the southern regions there has been a net reduction in forests. The influence of tourism facilities on forest is also variable. Around each of the tourism villages sampled there was a general trend of forest removal decreasing as the distance from each village increased, which indicates tourism does have a negative impact on forests. However, there was an opposite trend in the northern villages that were well inside the conservation area.  相似文献   
78.
2015年4月25日尼泊尔8.1级强烈地震前后,拉萨地磁台(以下简称“拉萨台”)地电场观测数据出现了长时间、大幅度异常变化。在对拉萨台地电场观测条件、观测系统以及观测结果进行初步讨论的基础上,利用“能量合成累加”和“MSA功率谱分析”等数据处理方法,从“时间域”和“频率域”两个方面,对该异常变化的主要特征和演化过程进行了分析。结果显示,尼泊尔8.1级地震前后,拉萨台的地电场观测数据异常变化,经历了“趋势变化一扰动变化一发震期一恢复期”等发展阶段,以及“低频变化一高频变化一平稳变化高频变化”等演化过程。综合分析认为,拉萨台地电场观测异常变化特征和演化过程,与相关现象和机理研究结果基本吻合,能够完整反映强烈地震孕育、发生和发展全过程,是具有一定客观性、典型性和代表性的珍贵资料。  相似文献   
79.
本文采用分层黏弹性介质模型, 模拟了2015年4月25日尼泊尔MS8.1地震产生的同震和震后地表位移场, 计算了尼泊尔大地震引起的青藏高原及其周缘主要断裂上的同震和震后库仑应力变化。 地表位移场结果显示, 此次尼泊尔8.1级地震对中国大陆的影响区域主要是拉萨地块和羌塘地块, 对拉萨块体的影响主要表现为水平向南朝喜马拉雅构造带的汇聚作用, 垂直同震位移以下降为主, 震后以上升为主。 静态库仑破裂应力变化的计算结果显示, 尼泊尔大地震对青藏块体中南部的拉张性断层影响最为显著, 其中, 使尼泊尔地震北部的拉张断层的库仑应力显著增加, 个别断层库仑应力增加量超过0.01MPa, 而使其两侧的拉张断层库仑应力明显降低; 对青藏块体中部的走滑断裂则以正影响为主; 另外, 对南北地震带主要以负影响为主, 但量值微小。  相似文献   
80.
Variations in fossil diatom assemblages and their relationship with global and Indian monsoon climate changes for the last 600,000 yr were investigated using a core of ancient lake (Paleo-Kathmandu Lake) sediments drilled at the Kathmandu Basin, Nepal Himalaya. Chronological scales of the core were constructed by tuning pollen wet and dry index records to the SPECMAP δ18O stack record. Examinations of biogenic silica contents and fossil diatom assemblages revealed that variations in productivity and compositions of diatom assemblages were closely linked with global and Indian monsoon climate changes on glacial and interglacial time scales. When summer monsoonal rainfall increased during interglacials (interstadials), diatom productivity increased because of increased inputs of terrestrial nutrients into the lake. When summer monsoonal rainfall reduced and/or winter monsoonal aridification enhanced during glacials (stadials), productivity of the diatoms decreased and lake-level falling brought about changes in compositions of diatom assemblages. Monospecific assemblages by unique Cyclotella kathmanduensis and Puncticulata versiformis appeared during about 590 to 390 ka. This might be attributed to evolutionary fine-tuning of diatom assemblages to specific lake environmental conditions. Additionally, low-amplitude precessional variations in monsoon climate and less lake-level changes may have also allowed both species to dominate over the long periods.  相似文献   
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