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Land Use Change and Its Effect on Environment Based on Farmers’Behaviors: A Case Study in Agricultural Areas of Tibet, China
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作者 ZHOUWei YANYan +1 位作者 ZENGYun-ying ZHONGXiang-hao 《Wuhan University Journal of Natural Sciences》 EI CAS 2005年第4期767-773,共7页
In the case study in Agricultural Area of Tibet, the process and characteristics of farmers' land use were surveyed by semi-structural interview questionnaire. By comparing the change of land covers and farmers... In the case study in Agricultural Area of Tibet, the process and characteristics of farmers' land use were surveyed by semi-structural interview questionnaire. By comparing the change of land covers and farmers' land decision in two periods, the spatial connection of them was obtained. And the relations among farmers' land decision, land use change and environment were examined by calculating emergy and value flow. The results show that: hunting the maximal profits is the primary aim of farmers' land decision; farmers' land decision is incompatible with sustainable land use presently; farmers' land decision and land cover can be embodied spatially by each other; the change of farmers' land decision can be monitored by observing the change of land cover, and the sustainability of farmers' land decision can be appraised by calculating emergy and value flow. 展开更多
关键词 Key words farmers' land decision land use change EMERGY value flow agricultural area of Tibet
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Complementarity of Sentinel-1 and Sentinel-2 Data for Mapping Agricultural Areas in Senegal
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作者 Gayane Faye Fama Mbengue +6 位作者 Lacina Coulibaly Mamadou Adama Sarr Modou Mbaye Amath Tall Dome Tine Omar Marigo Mouhamadou Moustapha Mbacke Ndour 《Advances in Remote Sensing》 2020年第3期101-115,共15页
The small size of agricultural plots is the main difficulty for crops mapping with remote sensing data in the Sahelian region of Africa. The study aims to combine Sentinel-1 (radar) and Sentinel-2 (Optic) data to disc... The small size of agricultural plots is the main difficulty for crops mapping with remote sensing data in the Sahelian region of Africa. The study aims to combine Sentinel-1 (radar) and Sentinel-2 (Optic) data to discriminate millet, maize and peanut crops. Training plots were used in order to analyse temporal variation of the three crops’ signals. T<span style="font-family:Verdana;">he NDVI (Normalized Difference Vegetation Index) was able to differentiate crops only at the end of the rainy season (October). </span><span style="font-family:Verdana;">The optical data as well as the radar ones could not easily discriminate the three crops during the growing season, because in that period vegetation cover is low, and soil contribution to the signals (due to roughness and moisture) was more important than that of real vegetation. However, the ratio of VH/VV (VH: incident signal in vertical polarization and reflected signal in horizontal polarization;VV: incident signal in vertical polarization and reflected signal in horizontal polarization) gave a difference between millet and the two other crops at the beginning cultural season (July 11). Difference appears from the second third of September when the harvest of cereals crops (millet and maize) began. From middle of October, the peanut signal dropped sharply thus facilitating the differentiation of peanut from the two other crops. This analysis led to the identification of data that have could be used to discriminate these crops (useful data). Classification of the combined useful data gave an overall high accuracy of 82%, with 96%, 61% and 65% for peanut, maize and millet, respectively. The non-agricultural areas (water, natural vegetation, habit, bare soil) were well classified with an accuracy greater than 90%.</span> 展开更多
关键词 agricultural areas Remote Sensing Sentinel-1 Sentinel-2 Senegal
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Available Agricultural Area by Utilization Categories and Ownership Structure of Holdings in the Republic of Serbia
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作者 Nada Trivić 《Natural Resources》 2020年第8期365-385,共21页
The subject of research in this paper is the analysis and presentation of data on agricultural holdings, the structure of available and utilized area. The data and calculated indicators represent a comprehensive overv... The subject of research in this paper is the analysis and presentation of data on agricultural holdings, the structure of available and utilized area. The data and calculated indicators represent a comprehensive overview of the structural characteristics of national agriculture, but they are also an internationally comparable database, based on key features of agriculture. The main goal of this paper is to determine and explain more comprehensively and in detail by using appropriate methods, and based on available data, the condition of <i><span style="font-family:Verdana;">utilized agricultural area</span></i><span style="font-family:Verdana;"> (hereinafter: UAA) and its quantitative and qualitative</span><span style="font-family:Verdana;"> characteristics by utilization categories and manner of its use;typ</span><span style="font-family:Verdana;">es of agricultural holdings and statistical regions and lower statistical units of data grouping. </span><span style="font-family:Verdana;">Implementation of such a defined basic research goal indicates necessity of more detailed and continuous study of the causes </span><span style="font-family:Verdana;">that led to the reduction of available agricultural area and especially its better and more important production categories of utilization and measures and activities to be taken to eliminate or reduce the causes of inadequate management of agricultural area in the coming period</span><span style="font-family:Verdana;">. The importance of this research arises from the fact that the results on </span><i><span style="font-family:Verdana;">utilized agricultural area</span></i><span style="font-family:Verdana;"> can be used to adopt </span><span style="font-family:Verdana;">appropriate measures and undertake certain activities in land and overall agricultu</span><span style="font-family:Verdana;">ral and rural policy related to sustainable utilization, arrangement and protection of agricultural land and more balanced integrated development of rural areas, as well as to find better solutions in the field of utilization, ownership sector and conditions of agricultural area management.</span> 展开更多
关键词 Utilized/Unutilized agricultural area agricultural Holdings Ownership Structure of agricultural Holdings
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THE LAST TRADE CARAVAN IN TIBET WANGCHEN WAS BUSY IN AN AGRICULTURAL AREA
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作者 GYAYANG XIRAB 《China's Tibet》 2007年第3期54-62,共9页
Setting off from Lhasa we followed Lhasa River,passing through Chushur County,then,driving along the banks of the Yarlung Tsangpo River,we finally arrived at Nyemo Bridge.Next we headed northward and into a long valle... Setting off from Lhasa we followed Lhasa River,passing through Chushur County,then,driving along the banks of the Yarlung Tsangpo River,we finally arrived at Nyemo Bridge.Next we headed northward and into a long valley.Finally,we reached Nyemo County.Although it was not a big county,it looked much more prosperous than Palgon County.A large government office building greeted us in a main street offering shops,both big and small,as well as restaurants-which also caught our eye.Nevertheless,the wandering la... 展开更多
关键词 THE LAST TRADE CARAVAN IN TIBET WANGCHEN WAS BUSY IN AN agricultural area WAS
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Confinement and Semi-confinement Raising Fattening Technology of Yaks in Agricultural Areas of Tibet
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作者 Bao Yuhong Feng Ke +4 位作者 Qu Guangpeng DunZhuJiaCai Wang Jiu Liao Yangci Shen Muyou 《Animal Husbandry and Feed Science》 CAS 2015年第5期267-268,283,共3页
In the study, confinement and semi-confinement raising fattening technology of yaks in agricultural areas of tibet were analyzed. And several suggestions for improving the efficiency of yak raising were put forward. A... In the study, confinement and semi-confinement raising fattening technology of yaks in agricultural areas of tibet were analyzed. And several suggestions for improving the efficiency of yak raising were put forward. Aiming at providing the reference of healthy raising and sustainable development of yaks in the agricul- tural areas of tibet. 展开更多
关键词 Agriculture areas of Tibet Yaks Fattening technology Study
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Exploration and Practice of Ideological and Political Teaching Construction for Biochemistry Course in Agricultural Colleges and Universities
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作者 Guanghong WU Peiqiang MU +1 位作者 Zhisheng ZHANG Guohui ZHU 《Agricultural Biotechnology》 2024年第1期31-35,42,共6页
Biochemistry is a fundamental core course in disciplines such as agriculture,forestry,medicine,animal husbandry,veterinary medicine,and food science.By prioritizing"educating people"in the teaching process o... Biochemistry is a fundamental core course in disciplines such as agriculture,forestry,medicine,animal husbandry,veterinary medicine,and food science.By prioritizing"educating people"in the teaching process of this professional course,we can unearth diverse ideological and political elements related to agricultural production practices within the curriculum knowledge system and the forefront of discipline development.Exploring various teaching methods and utilizing diverse teaching tools are effective strategies to achieve ideological and political education that silently influences students in the field of biochemistry.The goal is to nurture students strong ideals and beliefs,fostering a deep connection to the sentiments of"agriculture,rural areas and farmers in a great nation."This approach aims to instill a sense of responsibility towards strengthening agriculture,shaping students into individuals from South China Agricultural University who possess lofty aspirations and the courage to shoulder responsibility in the new era. 展开更多
关键词 BIOCHEMISTRY Curriculum ideology and politics "Agriculture rural areas and farmers in a great nation" Rural revitalization Exploration and practical application
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Spatial pattern and mechanisms of farmland abandonment in Agricultural and Pastoral Areas of Qingzang Plateau 被引量:2
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作者 Yuling Li Tao Zhou +3 位作者 Guanghui Jiang Guangyong Li Dingyang Zhou Yu Luo 《Geography and Sustainability》 2021年第3期139-150,共12页
With the rapid development of social economy and urban−rural integration,the phenomenon of farmland aban-donment worldwide has proved to be one of the main trends of land use and land cover change(LUCC),and profoundly... With the rapid development of social economy and urban−rural integration,the phenomenon of farmland aban-donment worldwide has proved to be one of the main trends of land use and land cover change(LUCC),and profoundly affected the rural landscape and regional ecological environment.Restricted by the natural environ-ment,economic development and backward agricultural technology,the phenomenon of farmland abandonment is also common in the Qingzang Plateau(QP).Therefore,this paper adopted the spatial autocorrelation method to analyze the spatial pattern of abandonment in the agricultural and pastoral areas of the Qingzang Plateau(APA−QP)in 2017,and the geographically weighted regression(GWR)model to explore the effects of geograph-ical resources,socio-economic development and location conditions on farmland abandonment.This study found that:1)From 2015 to 2017,the abandoned farmland area in the APA−QP was approximately 18.23×10^(4)ha,with an overall abandonment rate of 15.18%.On the whole,it showed the distribution characteristics of“strong in the south and weak in the north,strong in the east and weak in the west”.2)There were positive spatial correlation between both abandoned area and abandonment rate in the APA−QP,showing“concave”and“convex”patterns,respectively,mainly concentrated in the Huang−shui Valley and the Southeast Tibet;while in the western and northern regions,the degree of abandonment was relatively low.3)Farmland abandonment in the APA−QP was mainly driven by the geographical environment changes and farmers’decision−making on farmland utilization.There was significant spatial heterogeneity on farmland abandonment associated with the impact of geographical resources,socio−economics and location conditions.The geographical resource factors had a positive impact on the abandonment,and were strongly constrained by natural geographic conditions such as altitude and slope.The farmland resources in the Qingzang Plateau are limited,but are of strategic significance for the sustainable development of agriculture in the whole Qingzang Plateau.In order to realize the rational distribution of agricul-ture and animal husbandry and the sustainable utilization of farmland resources in the plateau region,land use strategies should be implemented according to regional differences and regional advantages in order to ensure the ecological environment security of Qingzang Plateau. 展开更多
关键词 Farmland abandonment Spatial pattern Formation mechanism Geographically weighted regression Qingzang Plateau agricultural and pastoral areas
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Preliminary Analysis of Special Tourism Transportation in Agricultural Eco-scenic Area
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作者 CHEN Xiaohong 《Journal of Landscape Research》 2015年第3期54-,共1页
Transport varies greatly in agricultural eco-scenic areas for the diversity of resources, and different terrains such as mountains, low hills and forest lands. Special tourism transportation is common in scenic area o... Transport varies greatly in agricultural eco-scenic areas for the diversity of resources, and different terrains such as mountains, low hills and forest lands. Special tourism transportation is common in scenic area of different themes. For agricultural eco-scenic area, the road design has to consider the theme of the scenic area, thus animal power is a favorable transportation choice, it refl ects agricultural ecological characteristics and also takes production needs into consideration. This paper analyzed road design characteristics of agricultural eco-scenic area, and proposed the transportation model dominated by animal power and considering farming production, so as to meet the standards of "rural road" in agricultural eco-scenic area and comply with the style of agricultural tourism, and satisfy the visitors. 展开更多
关键词 Special tourism transportation agricultural eco-scenic area Animal power
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Field Experience Exchange Meeting for the Northern Region of National Agricultural Standardization Demonstration Area Held
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《China Standardization》 2004年第6期16-16,共1页
关键词 Field Experience Exchange Meeting for the Northern Region of National agricultural Standardization Demonstration area Held
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Morphometry and Mineral Content in the Seeds and Soil of Two Species of Argemone L.(Papaveraceae)in the Central Part of the Chihuahuan Desert
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作者 Perla Patricia Ochoa-García Jaime Sánchez-Salas +2 位作者 Ricardo Trejo-Calzada Jesús JosafathQuezada-Rivera Fabián García-González 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第2期371-386,共16页
The genus Argemone L.(Papaveraceae)is found widely distributed in Mexico’s Chihuahuan Desert(CD).Some species of this genus are of phytochemical or ethnobotanical interest.They are inedible plants considered as scrub... The genus Argemone L.(Papaveraceae)is found widely distributed in Mexico’s Chihuahuan Desert(CD).Some species of this genus are of phytochemical or ethnobotanical interest.They are inedible plants considered as scrubs.To date they have not been broadly studied;thus,their ecology is,to our knowledge,unknown.The present work was centered around carrying out a morphometric analysis and the determination of minerals in the soil and seeds of the wild populations of Argemone at sites belonging to two ecoregions of the CD in Mexico.In April 2021 and April 2022,seeds of Argemone spp.,and soil samples were collected at 10 sites of the CD.The seeds were selected under a randomized design,and weight,length,diameter,thickness,buoyancy,and mineral content were determined.The soil samples were obtained under the Mexican regulation NOM-021-RECNAT-2000,and determinations of mineral content,electrical conductivity,apparent density,and soluble anions were performed.The information obtained was grouped by variable,species,and place of precedence.The statistical tests consisted of an ANOVA,Tukey means tests considering p≤0.05,and a Principal Components Analysis.Argemone pleiacantha exhibited differences in terms of weight(F=54.79,p=0.001),length(F=90.83,p=0.001),thickness(F=104.89,p=0.001),and diameter(F=155.82,p=0.001),and the differences in Argemone mexicana were in weight(F=46.71,p=0.001),thickness(F=187.49,p=0.001),length(F=191.56,p=0.001),and diameter(F=215.83,p=0.001).The evaluated seeds reached their maximal imbibition velocity at 24 h of evaluation.The content of the micro-and macro-nutrients analyzed in the seeds and soil suggest a tight relation with the morphometric characteristics of the seeds. 展开更多
关键词 MICRONUTRIENTS agricultural area semiarid zone ECOREGION BUOYANCY
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Heavy metal contamination and source in arid agricultural soil in central Gansu Province,China 被引量:28
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作者 LI Yu GOU Xin +3 位作者 WANG Gang ZHANG Qiang SU Qiong XIAO Guoju 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2008年第5期607-612,共6页
Concentrations of copper (Cu), lead (Pb), chromium (Cr), mercury (Hg), and arsenic (As) were measured in arid agricultural and irrigated agricultural soils collected in Daba Village, Shajiawuan Village, Gang... Concentrations of copper (Cu), lead (Pb), chromium (Cr), mercury (Hg), and arsenic (As) were measured in arid agricultural and irrigated agricultural soils collected in Daba Village, Shajiawuan Village, Gangou Village and Sifangwu Village, located in central Gansu Province, China. Concentrations except Hg and Pb were lower than the background values in grey calcareous soil in the selected arid agricultural soils. Pb concentration exceeded the threshold of arid agricultural soils in China by 72.46%. These results showed that there was indeed serious pollution with Pb, a slight pollution problem for other selected metals in the irrigated agricultural soils in Daba Village. Principal component analysis (PCA) was used to assess the soil data, applying varimax rotation with Kaiser Normalization. The result showed that the irrigated factor, agricultural factor and anthropogenic factor all contributed to the relations between selected chemical properties. The main factor of accumulation of Cu, Pb, Cr, Hg and As was lithological factor in arid agricultural areas. There is a striking dissimilarity of origin of Cu, Pb, Cr, Hg and As in agricultural soil between the irrigate agriculture and arid agriculture. 展开更多
关键词 arid agricultural area irrigate agriculture principal component analysis (PCA)
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A Comparative Study of Heavy Metal Concentration in Different Layers of Tannery Vicinity Soil and Near Agricultural Soil
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作者 Ashiqur Rahaman Jahan Sadia Afroze +2 位作者 Khairul Bashar Md. Farhad Ali Md. Razib Hosen 《American Journal of Analytical Chemistry》 2016年第12期880-889,共10页
This research was conducted to bring out the appropriate level of heavy metal contamination in soil at the site of Buriganga river bank near the Hazaribagh tannery area and the normal agricultural area to evaluate hea... This research was conducted to bring out the appropriate level of heavy metal contamination in soil at the site of Buriganga river bank near the Hazaribagh tannery area and the normal agricultural area to evaluate heavy metal contamination in soil due to untreated tannery effluents. AAS flame method was used to determine the concentration of Chromium (Cr), lead (Pb), Cadmium (Cd), Zinc (Zn) in several depths of the soil. Results showed that, the heavy metal concentration in soil at the site of Buriganga river bank in the tannery vicinity and normal agricultural area significantly varies, such as Cr varies (561.71 - 31.23) mg/kg, Zn varies (158.23 - 73.5), Pb varies (70.58 - 24) and Cd varies (2.25 - 0.71) mg/kg in the river bank as well as in the normal agricultural area Cr varies (27.869 - 24.5416) mg/kg, Zn varies (134.167 - 28), Pb varies (25.76 - 22.49) and Cd varies (1.30 - 0.64) mg/kg. The study indicated that heavy metals concentration was found to be significantly higher in river bank soils than in the normal agricultural area. This metal concentration in soil is responsible for the promotion of toxicity in agricultural products. Therefore, the human health and environment are affected by these areas. 展开更多
关键词 Heavy Metal SOIL CONTAMINATION Tannery area agricultural area
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Issues of "Agriculture, Rural Areas and Farmers" from the Perspective of Economy and Ideological System : Based on the Background of All-round Well-off Society
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作者 Jinquan WU 《Asian Agricultural Research》 2022年第12期19-21,共3页
Based on CNKI core journals and CSSCI database, "agriculture, rural areas and farmers" were used as the key words to summarize 20 core articles and CSSCI articles with "agriculture, rural areas and farm... Based on CNKI core journals and CSSCI database, "agriculture, rural areas and farmers" were used as the key words to summarize 20 core articles and CSSCI articles with "agriculture, rural areas and farmers" as the key words from 2015 to 2020, so as to let more researchers have a deeper understanding and grasp of China s current problems of "agriculture, rural areas and farmers". Through the method of comparative analysis of studies, the problems that need to be solved in the work of "agriculture, rural areas and farmers" were discussed, so that other scholars can further clarify the research results and experience of "agriculture, rural areas and farmers", so as to deepen the reform of rural land system and steadily promote the work of "agriculture, rural areas and farmers" in the future. This study can provide thinking and reference for deepening the reform of rural land system and steadily promoting the work of "agriculture, rural areas and farmers". 展开更多
关键词 "Agriculture rural areas and farmers" Rural areas FARMERS AGRICULTURE
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Analysis of Outdoor Cultivation of Pepino(Solanum muricatum)in Qinghai Province
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作者 Zhichao HOU Lihui WANG +5 位作者 Guangnan ZHANG Cheng SI Xueke TIAN Zhu SUN Dengkui SHAO Shipeng YANG 《Agricultural Biotechnology》 CAS 2023年第3期1-5,22,共6页
[Objectives]This study was conducted to explore the feasibility of planting pepino(Solanum muricatum Ait.)in Qinghai Province,and to understand the cultivation quality and yield in various areas of Qinghai.[Methods]Wi... [Objectives]This study was conducted to explore the feasibility of planting pepino(Solanum muricatum Ait.)in Qinghai Province,and to understand the cultivation quality and yield in various areas of Qinghai.[Methods]With small fruit type of pepino as the material,four areas in eastern Qinghai were selected to determine the agronomic traits,yield and quality indexes of pepino.[Results]Under the same cultivation conditions,there were some differences in the cultivation status of pepino,but overall,pepino fruit had higher quality.Various physiological indexes were correlated with quality and yield.[Conclusions]This study clarified the specific cultivation situation of pepino in Qinghai Province,and evaluated the quality and yield of pepino,providing strong data support for the promotion and planting of pepino in various regions in the future. 展开更多
关键词 PEPINO Eastern agricultural area of Qinghai Province YIELD Quality
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Research on layout of China leisure agriculture based on sustainable development
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作者 WANG Xiang-yang HOU Xiao-min 《Ecological Economy》 2017年第1期26-35,共10页
Leisure agriculture is a new form of agricultural production and management in the course of agricultural structure adjustment.It is an aggregation of agricultural production and tourism,high-tech and traditional agri... Leisure agriculture is a new form of agricultural production and management in the course of agricultural structure adjustment.It is an aggregation of agricultural production and tourism,high-tech and traditional agriculture,agricultural value and regional cultural values.There is the inseparable relationship between Leisure agriculture and sustainable development.Four agricultural areas of China have rich but different agricultural and tourist resources,by which different types of leisure agriculture can be layed out.It is important to make a right orientation for leisure agriculture in various agricultural areas for sustainable development of agriculture in China. 展开更多
关键词 leisure agriculture agricultural areas sustainable development agricultural distribution orientation of leisure agriculture
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A Study on the Transfer of Rural Surplus Labor in Nyingchi City
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作者 Luobu Dunzhu Yan HE 《Asian Agricultural Research》 2017年第5期36-38,共3页
This paper studies the surplus labor transfer in Nyingchi City,obtains the first-hand information of the surplus labor transfer through the typical survey,and analyzes the current situation and characteristics of surp... This paper studies the surplus labor transfer in Nyingchi City,obtains the first-hand information of the surplus labor transfer through the typical survey,and analyzes the current situation and characteristics of surplus labor transfer. From " transfer channel", " transfer industry" and " transfer space",this paper analyzes the factors affecting the transfer of local surplus farming and animal husbandry labor,discusses the obstacles to surplus farming and animal husbandry labor in Nyingchi City,and finally makes some recommendations for the transfer of rural surplus labor in Nyingchi City. 展开更多
关键词 agricultural and pastoral areas Surplus labor TRANSFER
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“Choosing the Refined”and“Collecting the Essential”and the Agricultural Revolution in the Area South of the Yangtze River during the Song Dynasty—An Examination of Traditional Research Methods in Economic History
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《Social Sciences in China》 2001年第2期136-144,共9页
关键词 and the agricultural Revolution in the area South of the Yangtze River during the Song Dynasty and Collecting the Essential An Examination of Traditional Research Methods in Economic History Choosing the Refined
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Key issues in promoting rural revitalisation in China 被引量:1
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作者 Zhong Tang Mingxi Han 《Economic and Political Studies》 2023年第2期149-173,共25页
Since the rural revitalisation strategy was first introduced in the 19th National Congress of the Communist Party of China,government agencies and scholars have put forward a series of indicators to measure its implem... Since the rural revitalisation strategy was first introduced in the 19th National Congress of the Communist Party of China,government agencies and scholars have put forward a series of indicators to measure its implementation.However,such a large number of indicators complicate the process.The rural revitalisation strategy aims to boost agricultural labour productivity,reduce the urban–rural income disparity,and promote the equalisation of basic public services,thereby accelerating the modernisation of agriculture and rural areas.This paper puts forward five indicators to evaluate the progress of implementing the rural revitalisation strategy.The indicators,though simple,underscore the key issues in promoting rural revitalisation in China.This paper also suggests that the rural revitalisation policy should aim to improve the quality of life of the rural population and promote the equalisation of basic public services rather than to reverse the population flow brought by industrialisation and urbanisation. 展开更多
关键词 Rural revitalisation INDICATORS modernisation of agriculture and rural areas
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DISTRIBUTIONS AND VARIATIONS OF SURFACE OZONE IN CHANGSHU,YANGTZE DELTA REGION 被引量:1
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作者 颜鹏 王木林 +1 位作者 程红兵 周秀骥 《Acta meteorologica Sinica》 SCIE 2003年第2期205-217,共13页
Through one and half year continuous in-situ measurements,the distributions and variations of surface ozone and its precursors at a typical mixed agricultural and metropolitan area- Changshu,Yangtze Delta region,were ... Through one and half year continuous in-situ measurements,the distributions and variations of surface ozone and its precursors at a typical mixed agricultural and metropolitan area- Changshu,Yangtze Delta region,were studied.The preliminary analysis on the concentration levels and variations of surface ozone indicated the obvious seasonal and diurnal cycles during the experiment.The hourly averaged concentrations of surface ozone were high,in about 17% of total valid hours the surface ozone concentration exceeded 50 ppb,and in 22 days the hourly averaged ozone concentration was greater than 100 ppb.There were about 40% of the days in that the daily maximum 8-hour ozone concentration was greater than 50 ppb.The days with daily maximum 8- hour ozone concentration greater than 80 ppb were about 33 days that accounted for about 8% of the observational days.The variations of 5-day moving averaged ozone concentrations depended both on the weather conditions and on the changes of ozone in background atmosphere. Photochemical process had the significant impacts on ozone productions. 展开更多
关键词 typical mixed agricultural and metropolitan area surface ozone impact on crop growth
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