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The Himalaya orogenic belt produces frequent large earthquakes that affect population centers along a length of over 2500 km
. The 2015 Gorkha, Nepal earthquake (Mw 7.8) ruptured the Main Himalayan Thrust (MHT) and allows direct measurements of the behavior of the continental collision zone. We study the MHT using seismic waveforms recorded by local stations that completely cover the aftershock zone. The MHT exhibits clear lateral variation along geologic strike, with the Lesser Himalayan ramp having moderate dip on the MHT beneath the mainshock area and a flatter and deeper MHT beneath the eastern end of the aftershock zone. East of the aftershock zone, seismic wave speed increases at MHT depths, perhaps due to subduction of an Indian basement ridge. A similar magnitude wave speed change occurs at the western end of the aftershock zone. These gross morphological structures of the MHT controlled the rupture length of the Gorkha earthquake
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[[[[[[[[[ Abstract: Sustainable development calls for the wise use of groundwater resources
. Of particular concern is saline intrusion into productive agricultural land, which is contiguous with densely populated coastal settlements. To reverse saline intrusion in such coastal regions, information about the groundwater depth in terms of its spatio-temporal variability is essential. Using survey data from 2004 to 2007, the research revealed the temporal variation characteristics of groundwater depth in the Contemporary Yellow River Delta. It explored the temporal stability characteristics of groundwater depth by using the coefficient of variation, Spearman rank correlation coefficient, and average relative deviation and standard deviation, and confirmed that the representative point reflected the average groundwater depth of the study area. Results showed that spatial variation of the groundwater depth in the study area was medium, but the variation coefficient of groundwater depth showed the seasonal changes. The spatial variation coefficient was largest in the dry season; the other months were relatively stable. The groundwater depth in the study area had strong temporal stability. The correlation between the Spearman rank correlation coefficient and the time lags showed that the spatial pattern of groundwater depth in the study area was similar across two or three years but the similarity weakened beyond this period. The representative points of the whole area showed a good linear correlation, and were spatially concentrated. In different years or time periods, the representative points were not the same but belonged to the medium groundwater depth grade in the area. The study provides useful guidance for Yellow River irrigation, preventing saline intrusion and the restoration of saline-alkali soils. It offers a theoretical basis for identifying regional satellite groundwater depth monitoring points
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The Tibetan plateau is the source of most of the major rivers of Asia and has a huge impact on the livelihoods of the population, who have for centuries engaged in traditional herding practices
. Sustainable management of the plateau is of critical importance not only for maintaining livelihoods but also because of its vital ecological function. The major problem of sustainable development in these grassland-livestock systems is the conflict between forage and livestock production. Despite considerable investment of manpower, material resources and capital over many years, attempts to resolve the problem have not been successful. The magnitude of conflict between forage and livestock is addressed by presenting 19 resolution strategies based on numerous research data. Each of these strategies is evaluated in terms of how it can be implemented, its potential benefits for livestock production, current progress and the requirement for further research. The 19 strategies have been divided into four topic categories, namely; grassland-forage, livestock, economy and market, society-culture, which cover the basic elements of sustainable development in this pastoral region. It is argued that improved planning and implementation of the proposed strategies must be based on the background investigation of natural and social status of the pastoral region. Particular attention needs to be given to genetic resources and technology in order to ensure the successful implementation of these proposals. In addition to expanding the use of 18 currently practiced strategies, the authors propose a further novel strategy of replacing the current intensive form of ecological migration with a model incorporating two semi-permanent settlements. The objective of this novel strategy is to retain the nomadic element of pastoral husbandry while increasing the temporal and spatial scale of rotational stocking to reduce pasture degradation on the Tibetan plateau. It is argued that these proposals should be urgently incorporated into two national plans for the pastoral livestock industry, and the construction of an ecologically safe shelter zone on the Tibetan plateau, while ensuring a sustainable livelihood of its pastoral residents. Ensuring a successful implementation of these strategies in resolving the conflict between grassland and livestock, and promoting sustainable development on the Tibetan plateau, requires willing support at the level of national investment and policy commitment and from the herdsmen
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Annotation:::: The paper examines issues related to the Nujiang Watershed of Yunnan province, which contains rich hydropower resources
. The development of Nujiang hydropower resources is important from an economic standpoint, and can contribute to alleviating poverty. However, Nujiang Watershed is also a habitat for many rare animals and plants, and the local “Three-Parallel Rivers of Yunnan Protected Areas” is listed as a world natural heritage site. The proposal of developing Nujiang hydropower resources has attracted concern from diffrent social sectors, and the issue of hydropower development’s impact has caused various debates. The paper focuses on human demography, and identifies the importance of developing Nujiang hydropower resources as well as the need to resettle local mountain people. The author uses the method of documental study and adopts demographic, socioeconomic and environmental perspectives in a qualitative analysis to discuss and analyse the benefits and adverse effects of Nujiang hydropower resource development on the local human-land relationship. The analysis focuses on four counties of Nujiang Lisu Autonomous prefecture of Yunnan province.After discussing the development of natural resources and resettlement of mountain people, the paper concludes that resettlement of local mountain people can promote the development of natural resources, and the development of natural resources can benefit resettled people and help alleviate poverty. Some policies are required to protect the interests of resettled people and promote the protection of local ecological environment
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The South Tibetan Detachment System is characterised by a lower ductile shear zone, an upper low-angle normal fault and high-angle normal faults
. The low-angle normal fault puts in contact the base of the Tibetan Sedimentary Sequence with the high-grade sillimanite-bearing schists and mylonitic leucogranites of the Greater Himlayan Sequence and, in several places, the intervening North Col Formation. In the Rongbuck valley, Sa’er and Nyalam areas (southern Tibet) a sharp contact of the low-angle normal fault is associated to breccias and cataclasites
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Secondary pyrrhotite remanences from the Tethyan Himalaya acquired during Eocene (western Himalaya) and Oligocene to early Miocene (central and eastern Himalaya) were evaluated for block rotations
. Oroclinal bending is well reflected by paleomagnetic data in the western part of the Himalaya also showing a uniform counterclockwise rotation of India versus the Tethyan Himalaya. In contrast, data from the central part and preliminary results from the eastern part indicate an abrupt change to unexpected clockwise rotations versus India where oroclinal bending would predict no rotation or slight counterclockwise rotations. It can be hypothesised that these clockwise rotations are a result of a large dextral shear zone related to lateral extrusion of the Tibetan Plateau, with an onset in central Nepal. However, the existing gap in suitable data from the eastern part of the Himalaya was hindering a closer evaluation of this question. The hypothesis is reconsidered in the light of new findings
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