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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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Under dual pressures of energy and environmental security, sweet sorghum is becoming one of the most promising feedstocks for biofuel production
. In the present study, the technical feasibility of sweet sorghum production was assessed in eight agricultural regions in China using the Sweet Sorghum Production Technique Maturity Model. Three top typical agricultural zones were then selected for further sustainability assessment of sweet sorghum production: Northeast China (NEC), Huang-Huai-Hai Basin (HHHB) and Ganxin Region (GX). Assessment results demonstrated that NEC exhibited the best sustainable production of sweet sorghum, with a degree of technical maturity value of 0.8066, followed by HHHB and GX, with corresponding values of 0.7531 and 0.6594, respectively. Prospective economic profitability analysis indicated that bioethanol production from sweet sorghum was not feasible using current technologies in China. More efforts are needed to dramatically improve feedstock mechanization logistics while developing new bioethanol productive technology to reduce the total cost. This study provides insight and information to guide further technological development toward profitable industrialization and large-scale sweet sorghum bioethanol production. © 2018 by the authors
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The national census data during 1995 and 2000 and during 2005 and 2010 are selected in this paper to make an analysis of the spatio-temporal characteristics of the inter-provincial population migration in China
. In addition, the general regression model, the extension regression model considering the historical dependent variable and the spatial lag model are established based on the gravity model to make the regression model on China's inter-provincial population migration over two periods of time. The results show that: (1) the inter-provincial population migration increases rapidly in size with strong geographical proximity; (2) China's inter-provincial population migration is still in the primary stage of the general process of population migration. In other words, the inter-provincial population emigration and immigration levels have increased greatly with the economic development; (3) Statistically, the inter-provincial population migration is negatively correlated with the level of economic development in the emigrant place and the migration distance and positively correlated with the level of economic development in the immigrant place and the population scale in the emigrant and immigrant places; and (4) The spatio-temporal factor is an important explanatory variable of population migration. The introduction of the historical dependent variable and the spatial lag factor can improve the regression effect of the gravity model greatly, and the historical variable and the spatial factor have strong explanatory power for the inter-provincial population migration
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© 2018 by the authors
. The valuation of ecosystem services is critical to understand the current status of ecosystems and to develop an effective planning strategy for ecosystem protection. This study aims to analyse the spatio-temporal changes in ecosystem services driven by land use changes from 1984 to 2013 in Dalian, China. The land use changes are characterized using remote sensing data and then ecosystem service values (ESVs) are assessed using the equivalent factor method, i.e., assigning value coefficients to different land use categories. The total ESV of Dalian reduced significantly by 44.3% from 1984 to 2013, primarily due to the reduction of forests, water and wetlands. Water and climate regulations are the two largest service functions, contributing about 43.6% of the total ESV on average. In addition, ESVs show a spatial variation in different administrative regions, with the central city area having the maximum decreasing rate. Further, ESV changes and distributions are found to have a strong link with city development policies. This study provides an enhanced understanding of the implications of urban policies on ecosystem services, which is essential for sustaining the provision of ecosystem services and achieving sustainable development goals
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Wang, P.; Wang, H.; Wang, Y. Q.; Zhang, X. Y.; Gong, S. L.; Xue, M.; Zhou, C. H.; Liu, H. L.; An, X. Q.; Niu, T.; Cheng, Y. L.
Emissions inventories of black carbon (BC), which are traditionally constructed using a bottom-up approach based on activity data and emissions factors, are considered to contain a large level of uncertainty
. In this paper, an ensemble optimal interpolation (EnOI) data assimilation technique is used to investigate the possibility of optimally recovering the spatially resolved emissions bias of BC. An inverse modeling system for emissions is established for an atmospheric chemistry aerosol model and two key problems related to ensemble data assimilation in the top-down emissions estimation are discussed: (1) how to obtain reasonable ensembles of prior emissions and (2) establishing a scheme to localize the background-error matrix. An experiment involving 1-year-long simulation cycle with EnOI inversion of BC emissions is performed for 2008. The bias of the BC emissions intensity in China at each grid point is corrected by this inverse system. The inverse emission over China in January is 240.1?Gg, and annual emission is about 2539.3?Gg, which is about 1.8 times of bottom-up emission inventory. The results show that, even though only monthly mean BC measurements are employed to inverse the emissions, the accuracy of the daily model simulation improves. Using top-down emissions, the average root mean square error of simulated daily BC is decreased by nearly 30?%. These results are valuable and promising for a better understanding of aerosol emissions and distributions, as well as aerosol forecasting
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Over a period of 5 years, two large earthquakes struck Sichuan Wenchuan and Lushan successively
. The two main seismic zones are only 87 km apart along the same seismic belt on the Longmenshan fault. Although there was only one magnitude of difference between the two great quakes, losses from the 2013 Lushan Earthquake were much lower than that of 2008 Wenchuan Earthquake. This study compares these disasters in terms of preparation and response in order to develop effective ways to reduce casualty and economic loss in future earthquakes. By determining what was done right after the Wenchuan Earthquake, we can better understand how to reduce future losses. This study focuses on seven factors: basic information, preparedness, government response, local residents’ responses, medical rescue teams’ work, earthquake-induced secondary effects, and injury character. We also recommend that three major actions should be emphasized to facilitate the most effective course of disaster planning and action. First, sufficient preparedness and strict preventive measures form the foundation to minimize damage and reduce casualties. Once the disaster had occurred, a single, well-run headquarters increases efficiency in rescue efforts. Finally, local rescue strength of both professional staff and citizens is the most critical factor to lower disaster casualties
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This research presents an evaluation of glacier recession and glacial-lake expansion in the Rongxer basin in the Mount Qomolangma National Reserve of central Himalaya
. Changes in glacier and glacial-lake surface areas in the Reserve between 1975, 1992 and 2005 have been estimated using remote sensing and GIS techniques that have integrated field data from 2009, 1:50,000 scale topographic maps, ASTER satellite data from 2009, and Landsat MSS/TM images in 1975, 1992 and 2005. By 2005, the glacier surface area had declined from 596.52 to 451.58 km2 with a total area loss of 144.94 km2, and glacial lakes had increased from 3.55 to 7.87 km2, an increase of 121.69 %. The volume of glaciers was reduced by 69.99 km3 from 1975 to 2005. The observed changes in the extent of glaciers are in line with the observed atmospheric warming in the Rongxer basin. Records from the Tingri station and Nyalam station have revealed warming during the ablation season since the 1970s at a rate of 0.03–0.04 °C a−1 in the northern and central Rongxer basin. At higher elevations in the study area, represented by the Tingri and Nyalam meteorological stations, the summer warming was accompanied by negative anomalies in annual precipitation since the 1970s, likely enhancing glacier retreat and glacial lake expansion
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Piao, S.; Ciais, P.; Huang, Y.; Shen, Z.; Peng, S.; Li, J.; Zhou, L.; Liu, H.; Ma, Y.; Ding, Y.; Friedlingstein, P.; Liu, C.; Tan, K.; Yu, Y.; Zhang, T.; Fang, J.
Global warming or the increase of the surface and atmospheric temperatures of the Earth, is increasingly discernible in the polar, sub-polar and major land glacial areas
. The Himalayan and Tibetan Plateau Glaciers, which are the largest glaciers outside of the Polar Regions, are showing a large-scale decrease of snow cover and an extensive glacial retreat. These glaciers such as Siachen and Gangotri are a major water resource for Asia as they feed major rivers such as the Indus, Ganga and Brahmaputra. Due to scarcity of ground measuring stations, the long-term observations of atmospheric temperatures acquired from the Microwave Sounding Unit (MSU) since 1979–2008 is highly useful. The lower and middle tropospheric temperature trend based on 30 years of MSU data shows warming of the Northern Hemisphere's mid-latitude regions. The mean month-to-month warming (up to 0.048±0.026°K/year or 1.44°K over 30 years) of the mid troposphere (near surface over the high altitude Himalayas and Tibetan Plateau) is prominent and statistically significant at a 95% confidence interval. Though the mean annual warming trend over the Himalayas (0.016±0.005°K/year), and Tibetan Plateau (0.008±0.006°K/year) is positive, the month to month warming trend is higher (by 2–3 times, positive and significant) only over a period of six months (December to May). The factors responsible for the reversal of this trend from June to November are discussed here. The inequality in the magnitude of the warming trends of the troposphere between the western and eastern Himalayas and the IG (Indo-Gangetic) plains is attributed to the differences in increased aerosol loading (due to dust storms) over these regions. The monthly mean lower-tropospheric MSU-derived temperature trend over the IG plains (dust sink region; up to 0.032±0.027°K/year) and dust source regions (Sahara desert, Middle East, Arabian region, Afghanistan-Iran-Pakistan and Thar Desert regions; up to 0.068±0.033°K/year) also shows a similar pattern of month-to-month oscillation and six months of enhanced and a statistically significant warming trend. The enhanced warming trend during the winter and pre-monsoon months (December–May) may accelerate glacial melt. The unequal distribution of the warming trend over the year is discussed in this study and is partially attributed to a number of controlling factors such as sunlight duration, CO2 trends over the region (2003–2008), water vapor and aerosol distribution
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Annotation :::: The paper focuses on administrative culture and problems faced by women, and considers the significance of protecting the rights of women migrants in the Three Gorges area as well as the responsiveness of public policies
. Using the methods of documental study and field research, the paper finds that women migrants are a particularly disadvantaged group among migrants in the Three Gorges area. Women’s rights should be viewed as human rights, rather than privileges. The rights of women migrants need the support of public policies, and also broader attention in society given that they have lost some of their legal rights and benefits in the course of migration. Both government and society should consider the role of women migrants in the stabilization and development of the Three Gorges area, and initiate a positive public policy response to protect their rights so as to promote the economic development of the Three Gorges area and overall development of society. The paper is part of the Hubei Provincial Social Sciences Foundation project directed by Professor Liu Xiaohong, numbered 2005/008 and titled “The Survival and Development Situation and Protection of Rights and Interests of Women and Children Emigrants in the Three Gorges Region
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Alpine vegetation and timberline development were investigated on 4 high mountains in North China: Mt
. Taibai (34°N, 108°E; 3767 m), Mt. Guandi (38°N, 111.5°E; 2831 m), Mt. Wutai (39°N, 113.6°E; 3058 m), and Mt. Xiaowutai (40°N, 115°E; 2882 m). The relationships between distribution of tree species and climatic factors on the uppermost parts of these mountains were established. As a result of the continental climate, their timberlines are composed of larch species, such as Larix chinensis on Mt. Taibai and Larix principis-rupprechtii on the other mountains. Two climatic indices, a warmth index (WI) and a humidity index (HI), were calculated for a differentiation of tree species near the timberline. A WI of 15°C mo has been commonly regarded as the limit for the timberline in East Asia. In addition, we suggest that the Larix timberline is formed when the HI is lower than 210. The understorey species of the forest patches inside the timberline and the L chinensis forest are similar on Mt. Taibai. These species are also distributed mostly in subalpine scrubs and meadows rather than in the Abies fargesii forest. This implies greater resistance to cold and drought in L chinensis than in A fargesii. Timberline movements were roughly reconstructed through analysis of sediments from the alpine zone of Mt. Taibai. A drier climate during 1830–1450 14C years BP resulted in a lower Abies timberline and was favorable for distribution of Larix, reflected by pollen diagrams and palaeolimnological evidence, such as grain size and total organic carbon. Percentages of Abies/Picea pollen recurred from 1450 to 680 14C years BP, implying an upward movement of Abies/Picea. Abies/Picea then moved downward, and the timberline was possibly replaced by Larix. In recent centuries, Picea/Abies has tended to move upward again
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