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1.
Mountain ecosystem,on the earth,has plenty of natural resources. In Himachal Pradesh all the rivers are snowfed and therefore rich in water resources. These resources have been supporting enough for the generation of electricity through introducing hydropower projects since the last decade. However,every developmental activity has its own negative impacts on the surrounding environment. Due to the fragile nature of topography and delicacy of ecology of the Himalaya,it results in lot of disturbances because of high degree of human interferences like construction of major hydropower projects. The increased extent of geological hazards,such as landslides,rock fall and soil erosion,have mainly due to alike developmental interventions in the natural ecosystem. So understanding and analysing such impacts of the hydropower projects have mainly been on the environment in various forms but natural hazards have been frequent ones. The present study,therefore,focuses mainly on the Parbati Stage Ⅱ (800 MW) and the Parbati Stage Ⅲ (520 MW) hydropower projects; both of which fall within the Kullu district of Himachal Pradesh. Based on the perception survey of the local communities,the existing land use pattern,status of total acquired land of the residents by hydropower projects,frequent natural hazards and resultant loss to the local communities due to upcoming construction of hydropower projects surrounding to the Parbati Stage Ⅱ and Ⅲ have been analysed in the paper. Also,the preventive measures to mitigate these adverse impacts have been suggested to strengthen these projects in eco-friendly manner in the mountain context.  相似文献   

2.
Two relief surfaces that envelop the rock fall region in a part of Garhwal Himalayas around Chamoli have been identified. Relative relief and absolute relief have been analyzed and the enveloping surfaces recorded at two levels of relief in the landscape. All landslide activity lies within these surfaces. The lower enveloping surface (800 m) dips due south by 7-8 degrees,due to an elevation rise of 100 meters within 12 km from south to north,i.e.,a gradient of 8 percent. The nature of the surface is smooth. The upper enveloping surface (> 2500 m) is almost parallel to the lower one but its surface is undulatory due to landslides and denudation. The area has been a seismically active region and has undergone seismic activity up until recently,as evidenced by the Chamoli earthquake of 29th March 1999. The effects of earthquakes are seen at higher levels in the form of landslide imprints on the terrain.  相似文献   

3.
Taking Nanjing as a case, the paper explains the spatial behavior differences existing in the information technology use among different groups of residents and households, by virtue of analyzing the survey data of urban households in the 11 districts of Nanjing, from the social, spatial, life and other non-technical angles. Also it makes various analyses and evaluation quantitatively and qualitatively on the social and spatial effect of information technology. The results show that the new technology is changing the social spatial behaviors of urban residents. New behavioral spaces of urban family such as telecommuting, email and QQ have begun to emerge. With the help of Internet, the communication scope of families has expanded greatly, and more new forms of publicizing community information have begun to emerge. Telecommunication contact forms have been developing swiftly, and their frequencies of con- tact have been increasing dramatically.  相似文献   

4.
Both China and Vietnam confront the challenges of natural geohazards and environmental changes in their deltas and coastal zones due to rapid urbanization, economic development, and the impacts of global climate change. China and Vietnam initiated a comparative study of the Holocene sedimentary evolution of the Yangtze River Delta(YRD) and Red River Delta(RRD) for the period 2015–2018 in order to improve the understanding of the two delta evolution histories in the Holocene. Previous investigative data of the two rivers, onshore delta plains, and offshore subaqueous deltas have been explored and reinterpreted. New data gleaned from boreholes, piston cores, shallow seismic and hydrodynamic sources have been collected from the offshore YRD and the East China Sea inner shelf, and surface sediments and short cores have been collected from the RRD near-shore areas. Six focal areas of the joint project have been defined for comparative studies of the two deltas, including morphological development, sequential stratigraphy, coastline shifting, sedimentary characteristics, sedimentary dynamics, and correlation with anthropogenic global climate change. The results of these study areas are presented herein. The joint project also includes cooperative capacity building; exchanges of young scientists have been organized during the project period, and hands-on training in laboratory geochemical analysis, numerical modeling, and seismic data processing and interpretation have been provided by China and its Vietnamese geoscientist partners. Joint field excursions were organized to the upstream of the Yangtze and Red Rivers in Yunan Province, China, all the way downstream along the Vietnamese portion of the Red River. These joint studies have, over the past three years, improved understanding of the evolutionary history of these two major rivers and their mechanisms of source to sink. Joint project results of these two major deltas are not limited to the geosciences; the cooperative mechanical and operational experiences have been helpful for future cooperation in the field of marine geoscience between China and Vietnam, as well for cooperative activities with other ASEAN member countries.  相似文献   

5.
By the study of metalflogenetic conditions and ore-controUing factors, the metallogenetic indicators in geology, geochemistry and geophysics about Wulaga gold deposit have been obtained. Using the indicators the blind ore bodies have been forecasted in Zhangcaigou area. By drilling check, a gold-bearing ore body with 3 m thickness in an average tenor of 20.4 × 10^-6at the depth of 70 m has been found in the forecast area. It shows that the forecast method should be effective.  相似文献   

6.
since 1978, rural urbanization has been accelerated in the Zhujiang (Pearl) River Delta because of the rapid development of commodity agriculture, industrialization and tertiary industry. Its natural urban population increase had been mostly mechanical before now, and the towns have been transformed from traditional centers into those serving various functions, particularly industrial ones.In the Zhujiang River Delta, population density and the level of economic changes are high in central areas, and low in outlying area, but on the other hand, urban population has increased slowly in central area and fast in outlying area. In the central areas more industrial towns emerge. So the gap has been greatly reduced. The reform of the construction of the region's economy, the improvement of transportation, the adjustment of the standard of town setting have promoted the distribution of the towns in the Zhujiang River Delta from being centralized to balanced.  相似文献   

7.
Economic inequality and poverty are problemsexperiencedbymanycountries.Considerable attention has been paid to these issues in recent times.Studies on economic inequality have been characterized by geographical disparities and a lack of consideration of functional orientation.As one of the most typical and featured mountainous areas in Western China,Tibet demonstrates both the necessity and urgency of conducting studies on income inequality and growth issues.This paper proposes to address these problems by exploring the temporal and geographical variations in income inequality in Tibet,thereby revealing the differences in functional zones.Spatial Markov chains and panel regression analysis were applied to identify the spatial-temporal dynamics of income disparity.The results of this study show that(1)the overall income inequality in Tibet shows an expanding trend in the period 2005–2010 and a converging trend in the period 2010–2015,and there is a large disparity in income inequality between functional zones;(2)Tibetan farmers and herdsmen may face great difficulties in achieving substantial growth in the near future;(3)frontier counties,cultivated land,and grassland areas have negative impacts on income growth,while cordyceps counties,GDP per capita,agricultural product proportion,transfer payments,the ratio of nonagricultural employment to the total employment,the length of the average schooling year,and the slaughter rate of cattle and sheep have positive impacts;and(4)functional orientation has made great differences to income inequality and its mechanism.In light of these results,evidence-based policies have been formulated to boost average household income and narrow income inequality in Tibet.  相似文献   

8.
Bioassays are important laboratory experiments in an attempt to interprete what is occurring in the field. The effect of various potential pollutants, especially heavy metals, on marine organisms has resulted in many studies in recent years. Polychaetous annelids have been one of the more commonly used test organisms because of their importance in the marine environment. Interlaboratory experiments have been conducted using the polychaetes Capitella capitata and Neanthes arenaceodentata (Pesch and Hoffman, in press) in which  相似文献   

9.
Paleontological and sedimentological analyses were carried out in sediment core from southeastern Mediterranean Sea, offshore Egypt to reconstruct the past environmental changes in trophic state and temperature during Holocene. To achieve our goals, grain size, total organic carbon, planktic and benthic foraminifera, dinoflagellate cysts have been investigated. Few micropalaentological studies have been done in the studied area and none of them used the combined proxies of benthic foraminifera and dinoflagellate cyst. Theses combined proxies reflects more comprehensive paleoenvironmental view. Biotic and abiotic data have been analysed with multivariate technique including Redundancy Analysis(RDA). Diversity indices such as: Fisher alpha index(α) and Shannon index(H) have been applied. The foraminiferal study yields 9 planktic species and 10 benthic species. Foraminiferal assemblages have low species diversity indices especially at sapropel layer S1. Mediterranean sapropels are layers with elevated organic carbon concentrations that contrast with surrounding organic poor sediments. Sapropels occur periodically in sedimentary sequences of the last millions years, which have been the subject of extensive previous study. Redundancy Analysis(RDA) yields two groups of foraminiferal assemblages depending on the changes of total organic carbon and clay content. The dinocysts study yields 15 species, the majority of cyst types belonging to the order Gonyaulacales. The association of dinoflagellate cyst shows two depositional phases in the sediment. The sapropel layer S1, with anoxic condition and warmer temperature, is recorded at depth 28-46 cm where heterotrophic taxa dominate and the post-sapropel layer is recorded at depth 0-28 cm; where autotrophic taxa dominate.  相似文献   

10.
The secretion function of mantle is closely related to shell formation in some bivalves and gastropods. Up to now, few researches have been reported for cuttlebone formation in the class Cephalopoda. In this study, the structure and secretion function of cuttlebone sac of the golden cuttlefish Sepia esculenta was analyzed using the histological and histochemical methods. The results showed that high and columnar cells located in sac epithelium, and flat cells existed near the base membrane. A lot of fibroblasts were found in the lateral mantle collective tissue. Some mucus, mucopolysaccharide and alkaline phosphatase (ALP) were found in the sac. The ultrastructural characteristics of Quasi-connective-tissue-calcium cells (QCTCC) were observed using a transmission electron microscope (TEM). The relationship between cuttlebone sac secretion function and shell formation was discussed.  相似文献   

11.
The rapidly developing rural tourism industry in China has deeply influenced the livelihoods of rural households. This study compares the impact of rural tourism development in poor areas on the farmers’ livelihoods, based on the Sustainable Livelihoods Framework proposed by the United Kingdom’s Department for International Development. Gougezhuang, a tourist village, and Jiaojiekou, a non-tourist village, both located in Yesanpo Tourism District in the state-level povertystricken Laishui County, Hebei Province, were selected as case studies. The livelihood models of the two villages show great differentiation after 20 years of tourism development. Gougezhuang Village has been driven by the tourism industry and farmers are employed locally, enjoying a relatively higher-income life, with a developmental livelihood model. In contrast, farmers in Jiaojiekou Village earn their living mainly by leaving home to work in the city. They have a low income, with a survival livelihood model, supported by part-time business. Considering that the two villages are adjacent and have similar development backgrounds, the analysis results indicate that rural tourism has an apparent locationspecific effect on poverty alleviation and socioeconomic development, but the development of rural tourism is limited regarding large-scale poverty alleviation efforts in poor areas. To implement a propoor- tourism strategy and achieve sustainable development, it is necessary to implement comprehensive management measures to change the local conditions of rural settlements and make full use of the spillover effect of tourist consumption.  相似文献   

12.
The relationship between livelihood diversification of farm households and cultivated land utilization has become a core research topic related to global environmental change. Agro-pastoral ecologically-vulnerable areas face challenges such as insufficient ecosystem conservation, low agricultural production, and weak economies. In this study, 215 farm households from Zhengxiangbai Banner, Taibus Banner, and Duolun County of Inner Mongolia were surveyed. The sustainable livelihoods framework of the United Kingdom(UK) Department for International Development(DFID) was used to measure the livelihood capital of these farm households. A one-way analysis of variance(ANOVA) was applied to examine the differences in the livelihood capital of different types households, and a correlation analysis was applied to analyze its impact on cultivated land utilization. Results showed that households with non-farming activities accounted for 64.7% of the total surveyed households, and non-farming employment was becoming more prevalent. Physical and financial capital was the driving factors for livelihood diversity. Each livelihood capital had key factors that affected household farmland use behaviors, such as the age of householder, the labor ratio, proportion of income, farmland scale, number of machines, and these had a significantly positive or negative influence on farmland use. Full-time farming households were more likely to transfer the land into cultivation and invest more labor, while non-farming households with high income were likely to transfer farmland out and invest more money to develop efficient farming or improve the employment skills. The results of this study suggest that policymakers need to fully consider livelihood changes of local households. It is effective to strengthen labor training, create farmland market and improve the efficiency of farmland utilization. We hope to achieve a win-win scenario to improve local economies and ecosystem conservation.  相似文献   

13.
According to historical records, there are 264 drought and flood years, occurred in the upper and middle reaches of the Changjiang (Yangtze) River during last 1020 years from 961 to 1980. The evolutionary law and developing trend of drought and flood years are studied. The distribution of drought and flood years are non-uniform and the dry and flood seasons in a year are concentrated. At the angle of monsoon circulation, at present the climate in the upper and middle reaches of the Changjiang River is just in the late stage of frequent drought period and the early stage of least flood period. In addition, the cycle of drought and flood and the feature of drought and flood occurred in the upper, middle and lower reaches of the Changjiang River are analyzed. It shows that the short period less than 10 years is in the majority, and the drought and flood occurred most frequently in the middle and lower reaches of the Changjiang River.  相似文献   

14.
Research on the sustainable livelihoods of rural households is of great significance to mitigating rural poverty and reasonable land expropriation policy helps to realize better livelihoods and sustainable development. Scholars have conducted considerable research on the relationships between land expropriation and farmers. livelihoods. However,few quantitative studies have used the characteristics of villages as control variables to systematically analyze the impact of land expropriation on farmers.livelihood capital and strategy in the mountainous and hilly regions of China. This study uses the Partial Least Squares-Structural Equation Model(PLS-SEM)to systematically explain the impact of landexpropriation on farmers. livelihoods in mountainous and hilly regions of Sichuan in 2013, with the characteristics of the village including income,accessibility and terrain as control variables. The analysis uses both representative sample data of 240 rural households and spatial data calculated using a 30 m Digital Elevation Model(DEM) by Geographic Information System(GIS). Results are as follows:(1)The land expropriation characteristics are negatively affected by village accessibility. Villages with worse accessibility tend to have fewer land parcels and less land area expropriated. Additionally, land that is expropriated from inaccessible villages tends to receive less compensation.(2) Natural capital is negatively affected by number and area of land expropriation. Natural capital is not only directly affected by village accessibility, but also indirectlyaffected by village accessibility through the mediating effect of the number and area of land parcels expropriated.(3) Physical capital is positively affected by compensation for land expropriation, and negatively affected by village accessibility through compensation for land expropriation. The worse a village.s accessibility/location is, the less compensation it will receive for land expropriation,resulting in lower physical capital.(4) Financial capital is negatively affected by village accessibility indirectly through compensation for land expropriation. The better the village.s accessibility is,the greater is its compensation for land expropriation and, hence, the greater is its financial capital.(5)Social capital is directly and negatively affected by the number and area of land parcels expropriated, and is indirectly and positively affected by village accessibility through the number and area of land parcels expropriated. This study enhances our understanding of the characteristics of land expropriation and rural households. livelihood as well as the impact of land expropriation on rural households. livelihood. These findings provide reference for the formulation of proper policies related to land expropriation and the improvement of rural households. livelihoods in the mountainous and hilly regions of China.  相似文献   

15.
The main reasons for the high content of inorganic N and its increase by several times in the Changjiang River and its mouth during the last 40 years were analysed in this work. The inorganic N in precipitation in the Changjiang River catchment mainly comes from gaseous loss of fertilizer N, N resulting from the increases of population and livestock, and from high temperature combustions of fossil fuels. N from precipitation is the first N source in the Changjiang River water and the only direct cause of high content of inorganic N in the Changjiang River and its mouth. The lost N in gaseous form and from agriculture non-point sources fertilizer comprised about 60% of annual consumption of fertilizer N in the Changjiang River catchment and were key factors controlling the high content of inorganic N in the Changjiang River mouth. The fate of the N in precipitation and other N sources in the Changjiang River catchment are also discussed in this paper.  相似文献   

16.
Traditional farming practices conform to sustainable rural livelihoods, while agricultural modernisation tends to undermine these practices through various perturbations. A case study in Tengchong County (western Yunnan, China) shows that transformation of traditional alder (Alnus nepalensis) and dry rice (upland rice) rotational farming to introduced Chinese fir (Cunninghamia lanceolata (Lamb.) Hook.) plantations leads to localised water scarcity and soil fertility decline. While farmers are aware of ecological sustainability of traditional farming, they prefer Chinese fir forestry because it is less labour-intensive, has a high market value, and releases time for profitable off-farm work. Farmers adapt to economic liberalization by planting high value crops and trees. However, alternatives to make local agricultural production more profitable through competitive business strategies, cooperative approaches, innovations in integrating high value crops and ‘downstream’ processing for sustainable rural livelihoods have been overlooked largely due to poor information availability and lack of organisational framework.  相似文献   

17.
Land use change in rural China since the 1980s, induced by institution reforms, urbanization, industrialization and population increase, has received more attention. However, case studies on how institution reforms affect farmers’ livelihood strategies and drive land use change are scarce. By means of cropland plots investigations and interviews with farmers, this study examines livelihood strategy change and land use change in Danzam Village of Jinchuan County in the upper Dadu River watershed, eastern Tibetan Plateau, China. The results show that, during the collective system period, as surplus labor forces could not be transferred to the secondary and tertiary industries, they had to choose agricultural involution as their livelihood strategy, then the farmers had to produce more grains by land reclamation, increasing multiple cropping index, improving input of labor, fertilizer, pesticide and adopting advanced agricultural techniques. During the household responsibility system period, as labors being transferred to the secondary and tertiary industries, farmers chose livelihood diversification strategy. Therefore, labor input to grain planting was greatly reduced, which drove the transformation of grain to horticulture, vegetable or wasteland and decrease of multiple cropping index. This study provides a new insight into understanding linkages among institution reforms, livelihood strategy of smallholders and land use change in rural China. Foundation item: Under the auspices of National Natural Science Foundation of China (No. 40601006, 40471009), National Basic Research Program of China (No. 2005CB422006)  相似文献   

18.
In China, rural settlements are usually multifunctional complex of natural societies and they also play important productive function. This study explored the spatiotemporal evolution of the productive function of three rural settlements, i.e., Hetaoyuan, Dawengshan, and Gaoqiao, in the Yimeng Mountain in Shandong province of eastern China. Residents lived in this three types of rural settlements were all involved in agricultural production (i.e., grain threshing, drying and storage), which had remained dominant in Hetaoyuan. Dawengshan became an industrial-oriented settlement, while Gaoqiao became a commercial-oriented settlement. This evolution was reflected in the livelihood strategy changes of rural households and the transition of rural settlements changes. The choice of livelihood strategy was affected by the livelihood assets and policies, which resulted in the spatiotemporal evolution of the productive function of rural settlements. This study can provide references for the implementation and adjustment of rural residential land consolidation policies and the improvement of production and the quality of rural life in future.  相似文献   

19.
China is a mountainous country,and Southwest mountain areas cover the most mountain areas in China and have the most serious problems.Taking Zhaotong city as the study area,based on 902 rural household questionnaires of 11 villages in 2 counties and Tobit model,this paper analyzes the geographical differences and influencing factors of energy consumption for non-production purposes of rural households living in different terrain conditions.This research finds that:(1) Coal takes up the main part of energy consumption in valley areas and coal consumption is mainly affected by per capita cultivated land area,household income,proportion of rural household energy expenditure in total expenditure,coal price,and family population size.Firewood takes up the main part of energy consumption in high mountain areas and firewood consumption is mainly affected by per capita firewood forest area,distance to purchase coal,household income,electricity price,and coal price.(2) Only when the distance is greater than 20 kilometers,that is the average distance of rural households living in middle mountain areas(1,600m~1,800m) to purchase coal,the transportation condition has a significant impact on coal consumption.(3) In high mountain areas,prices of coal and electricity are the main factors influencing energy consumption choice of rural households.Too high prices of coal and electricity would to some extent lead rural households to choose firewood as the main energy consumption type.Compared to coal,rural households prefer to choose electricity.  相似文献   

20.
1INTRODUCTIONIt is one of important issues in the field of geographical science to analyze the spatial differentiation of regional phenomenon. The research on spatial differentiation can be cast back to Thunen's agricultural location theory. Af- terwards, many scholars developed the theory and paid moreattentiontothelawandformingmechanismofspa- tial differentiation of some phenomena including inhabi- tation structure, population variation, environmental ele- ments, rural development, and …  相似文献   

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