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卫星观测陆表温度日变化对全球陆面同化系统陆表温度模拟的影响
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作者 付士稳 聂肃平 +1 位作者 罗勇 陈欣 《地理学报:英文版》 SCIE CSCD 2020年第1期18-36,共19页
Based on the Beijing Climate Center’s land surface model BCC_AVIM(Beijing Climate Center Atmosphere-Vegetation Interaction Model),the ensemble Kalman filter(EnKF)algorithm has been used to perform an assimilation exp... Based on the Beijing Climate Center’s land surface model BCC_AVIM(Beijing Climate Center Atmosphere-Vegetation Interaction Model),the ensemble Kalman filter(EnKF)algorithm has been used to perform an assimilation experiment on the Moderate Resolution Imaging Spectroradiometer(MODIS)land surface temperature(LST)product to study the influence of satellite LST data frequencies on surface temperature data assimilations.The assimilation results have been independently tested and evaluated by Global Land Data Assimilation System(GLDAS)LST products.The results show that the assimilation scheme can effectively reduce the BCC_AVIM model simulation bias and the assimilation results reflect more reasonable spatial and temporal distributions.Diurnal variation information in the observation data has a significant effect on the assimilation results.Assimilating LST data that contain diurnal variation information can further improve the accuracy of the assimilation analysis.Overall,when assimilation is performed using observation data at 6-hour intervals,a relatively good assimilation result can be obtained,indicated by smaller bias(<2.2K)and root-mean-square-error(RMSE)(<3.7K)and correlation coefficients larger than 0.60.Conversely,the assimilation using 24-hour data generally showed larger bias(>2.2K)and RMSE(>4K).Further analysis showed that the sensitivity of assimilation effect to diurnal variations in LST varies with time and space.The assimilation using observations with a time interval of 3 hours has the smallest bias in Oceania and Africa(both<1K);the use of 24-hour interval observation data for assimilation produces the smallest bias(<2.2K)in March,April and July. 展开更多
关键词 land surface data assimilation land surface temperature MODIS diurnal variation
Rural Land Rights in China:Evolution and Case Studies 预览
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作者 刘守英 熊雪锋 龙婷玉 《中国经济学人:英文版》 2020年第2期109-120,共12页
Constant divisions of rural land rights and contract renegotiations are the hallmark of China’s collective ownership system.Rural land ownership,property and operation systems in China have experienced four stages of... Constant divisions of rural land rights and contract renegotiations are the hallmark of China’s collective ownership system.Rural land ownership,property and operation systems in China have experienced four stages of evolution:(i)The People’s Communes,which served administrative and economic functions,exercised integrated collective land ownership,property,and operation rights.(ii)Under the system of“threetier ownership with production teams as basic accounting units,”production teams exercised the ownership right over land plots with greater autonomy and were responsible for organizing farm work.(iii)The household contract system has entitled farmers to claim surplus products and turned farm households into the basic unit of agricultural production.Subsequently,the reform of collective ownership has further enhanced farmers’contract rights and separated their operation rights from contract rights.The separation of rural land ownership,contract and operation rights marks a top-down design of the structure of China’s rural land rights after the collective ownership system and the reform of household contract system.By recognizing separate contract and operation rights without changing collective ownership,the separation aims to protect rural land contract and operation rights in accordance with the law.As in the four case studies,Chongzhou,Songjiang,Meitan and Liupanshui have experienced a restructuring of collective ownership,contract and operation rights.Their experience foretells complexities in the future evolution of rural land rights in China. 展开更多
关键词 collective ownership land rights division of land rights institutional evolution
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Spatial-temporal Dynamics and Driving Forces of Land Development Intensity in the Western China from 2000 to 2015 预览
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作者 HUANG Xin HUANG Xiaojun +2 位作者 LIU Mengmeng WANG Bo ZHAO Yonghua 《中国地理科学:英文版》 SCIE CSCD 2020年第1期16-29,共14页
The change in land development intensity is an important perspective to reflect the variation in regional social and economic development and spatial differentiation.In this paper,spatial statistical analysis,Ordinary... The change in land development intensity is an important perspective to reflect the variation in regional social and economic development and spatial differentiation.In this paper,spatial statistical analysis,Ordinary Least Squares(OLS),and Geographically weighted regression(GWR)methods are used to systematically analyse the spatial-temporal characteristics and driving forces of land development intensity for 131 spatial units in the western China from 2000 to 2015.The findings of the study are as follows:1)The land development intensity in the western China has been increasing rapidly.From 2000 to 2015,land development intensity increased by 3.4 times on average.2)The hotspot areas have shifted from central Inner Mongolia,northern Shaanxi and the Beibu Gulf of Guangxi to the Guanzhong Plain and the Chengdu-Chongqing urban agglomeration.The areas of cold spots were mainly concentrated in the Qinghai-Tibet Plateau,Yunnan,and Xinjiang.3)Investment intensity and the natural environment have always been the main drivers of land development intensity in the western China.Investment played a powerful role in promoting land development intensity,while the natural and ecological environment distinctly constrained such development.The effect of the economic factors on land development intensity in the western China has changed,which is reflected in the driving factor of construction land development shifting from economic growth in 2000 to economic structure,especially industrial structure,in 2015. 展开更多
关键词 construction land land development intensity spatial-temporal dynamic driving force the western China
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Rural Land System Reform Pilot Experiment in Pidu District:Background,Debate and Enlightenment 预览
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作者 Hong Yun 《当代社会科学(英文)》 2020年第1期27-39,共13页
By combining top-level design with local pilot practices,rural land system reform,as an important priority on the agenda of deepening comprehensive reform,has accumulated a series of replicable and applicable experien... By combining top-level design with local pilot practices,rural land system reform,as an important priority on the agenda of deepening comprehensive reform,has accumulated a series of replicable and applicable experiences that are conducive to amendments to relevant laws.This paper takes stock of the basic experience of Pidu District in addressing typical problems arising in its rural land system reform and then investigates the inner link between the reform and the persistence of high housing prices in cities,the capital flowing to the countryside,and the rural revitalization program.Based on this analysis,the author puts forward three basic directions of the rural land system reform:remain committed to marketization,balance the interests of all parties and promote the development of rural industries. 展开更多
关键词 rural land system REFORM Pidu District pilot experiment
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Land Cover Changes and Drivers in the Water Source Area of the Middle Route of the South-to-North Water Diversion Project in China from 2000 to 2015 预览
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作者 GAO Wenwen ZENG Yuan +2 位作者 ZHAO Dan WU Bingfang REN Zhiyuan 《中国地理科学:英文版》 SCIE CSCD 2020年第1期115-126,共12页
The Middle Route of the South-to-North Water Diversion Project(MR-SNWDP)in China,with construction beginning in 2003,diverts water from Danjiangkou Reservoir to North China for residential,agriculture and industrial u... The Middle Route of the South-to-North Water Diversion Project(MR-SNWDP)in China,with construction beginning in 2003,diverts water from Danjiangkou Reservoir to North China for residential,agriculture and industrial use.The water source area of the MR-SNWDP is the region that is most sensitive to and most affected by the construction of this water diversion project.In this study,we used Landsat Thematic Mapper(TM)and HJ-1 A/B images from 2000 to 2015 by an object-based approach with a hierarchical classification method for mapping land cover in the water source area.The changes in land cover were illuminated by transfer matrixes,single dynamic degree,slope zones and fractional vegetation cover(FVC).The results indicated that the area of cropland decreased by 31%and was replaced mainly by shrub over the past 15 years,whereas forest and settlements showed continuous increases of 29.2% and 77.7%,respectively.The changes in cropland were obvious in all slope zones and decreased most remarkably(–43.8%)in the slope zone above 25°.Compared to the FVC of forest and shrub,significant improvement was exhibited in the FVC of grassland,with a growth rate of 16.6%.We concluded that local policies,including economic development,water conservation and immigration resulting from the construction of the MR-SNWDP,were the main drivers of land cover changes;notably,they stimulated the substantial and rapid expansion of settlements,doubled the wetlands and drove the transformation from cropland to settlements in immigration areas. 展开更多
关键词 remote sensing land cover change object-based classification Middle Route of the South-to-North Water Diversion Project(MR-SNWDP) China
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自然资源资产负债表研究现状、评述与改进方向 预览
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作者 史丹 王俊杰 《中国人口资源与环境》 CSSCI CSCD 北大核心 2020年第1期1-11,共11页
自然资源资产负债表概念是中国的一项重要理论和制度创新,但其研究还存在一些问题和争议,如对自然资源资产负债表中资源类别未能达成共识,对资产、负债和权益的界定不清晰,价值核算还不准确等。此外,其编制工作也进展缓慢。本文认为,自... 自然资源资产负债表概念是中国的一项重要理论和制度创新,但其研究还存在一些问题和争议,如对自然资源资产负债表中资源类别未能达成共识,对资产、负债和权益的界定不清晰,价值核算还不准确等。此外,其编制工作也进展缓慢。本文认为,自然资源资产负债表基础理论和方法都尚不成熟,需要重新诠释概念,并引入新的核算方法,使其中的资产、负债和权益概念更加清晰,数量核算和价值核算方法更加科学。可以另辟蹊径,借鉴生态足迹的思想,从三方面做出改进:第一,将资源类别界定为耕地、林地、草地、湿地、水域、能源矿产和非能源矿产七类,以避免重复核算问题。第二,进一步明确土地和矿产两类资源的资产、负债和权益的含义,可以引入生态足迹方法,用土地生态足迹、生态承载力和生态赤字分别衡量土地资产、土地权益和土地(过载)负债,使得土地过载负债的核算成为可能,且在土地权益核算时能够同时考虑土地面积和质量;可以用已消耗的矿产资源衡量环境负债,以避免环境负债价值的系统性偏误问题。第三,可以将生态足迹方法与生态系统服务价值评估方法结合起来,以估算土地的资产、权益和负债价值,以避免土地价值估算的系统性偏误问题;可以用改进的市场价格法核算矿产或环境的三种价值,避免环境负债价值核算的随意性。引入生态足迹方法可以使自然资源资产负债表中的资产、负债和权益概念更加清晰易懂,并使得资源的数量核算和价值核算方法更加科学,结果更加可信。 展开更多
关键词 自然资源资产负债表 数量核算 价值核算 土地 矿产 生态足迹
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基于重心-GTWR模型的京津冀城市群研究
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作者 王海军 张彬 +5 位作者 刘耀林 刘艳芳 徐姗 赵雲泰 陈宇琛 洪松 《地理学报:英文版》 SCIE CSCD 2020年第2期297-318,共22页
Research into urban expansion patterns and their driving forces is of great significance for urban agglomeration development planning and decision-making.In this paper,we reveal the multi-dimensional characteristics o... Research into urban expansion patterns and their driving forces is of great significance for urban agglomeration development planning and decision-making.In this paper,we reveal the multi-dimensional characteristics of urban expansion patterns,based on the intensity index of the urban expansion,the differentiation index of the urban expansion,the fractal dimension index,the land urbanization rate,and the center of gravity model,by taking the Beijing-Tianjin-Hebei(Jing-Jin-Ji)urban agglomeration as an example.We then build the center of gravity-geographically and temporally weighted regression(GTWR)model by coupling the center of gravity model with the GTWR model.Through the analysis of the temporal and spatial patterns and by using the center of gravity-GTWR model,we analyze the driving forces of the urban land expansion and summarize the dominant development modes and core driving forces of the Jing-Jin-Ji urban agglomeration.The results show that:1)Between 1990 and 2015,the expansion intensity of the Jing-Jin-Ji urban agglomeration showed a down-up-down trend,and the peak period was in 2005-2010.Before 2005,high-speed development took place in Beijing,Tianjin,Baoding,and Langfang;after 2005,rapid development was seen in Xingtai and Handan.2)Although the barycenter of cities in the Jing-Jin-Ji urban agglomeration has shown a divergent trend,the local interaction between cities has been enhanced,and the driving forces of urban land expansion have shown a characteristic of spatial spillover.3)The spatial development mode of the Jing-Jin-Ji urban agglomeration has changed from a dual-core development mode to a multi-core development mode,which is made up of three functional cores:the transportation core in the northern part,the economic development core in the central part,and the investment core in the southern part.The synergistic development between each functional core has led to the multi-core development mode.4)The center of gravity-GTWR model combines the analysis of spatial and temporal nonstationarity with 展开更多
关键词 urban land expansion driving forces center of gravity geographically and temporally weighted regression Jing-Jin-Ji
气候变化驱动下的欧亚大陆土地覆盖情景模拟
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作者 范泽孟 白茹玉 岳天祥 《地理学报:英文版》 SCIE CSCD 2020年第1期3-17,共15页
The method for surface modelling of land cover scenarios(SMLCS)has been improved to simulate the scenarios of land cover in Eurasia.On the basis of the observation monthly climatic data observed from 2127 weather stat... The method for surface modelling of land cover scenarios(SMLCS)has been improved to simulate the scenarios of land cover in Eurasia.On the basis of the observation monthly climatic data observed from 2127 weather stations in Eurasia during 1981-2010,the climatic scenarios data of RCP26,RCP45 and RCP85 scenarios released by CMIP5,and the land cover current data of Eurasia in 2010,the land cover scenarios of Eurasia were respectively simulated.The results show that most land cover types would generally have similar changing trends in the future,but with some difference in different periods under the three scenarios of RCP26,RCP45 and RCP85.Deciduous needleleaf forest,mixed forest,shrub land,wetlands and snow and ice would generally decrease in Eurasia during 2010-2100.Snow and ice would have the fastest decreasing rate that would decrease by 37.42%on average.Shrub land would have the slowest decreasing rate that would decrease by 5.65%on average.Water bodies would have the fastest increasing rate that would increase by 28.78%on average.Barren or sparsely vegetated land would have the slowest increasing rate that would increase by 0.76%.Moreover,the simulated results show that climate change would directly impact on land cover change in Eurasia. 展开更多
关键词 SMLCS climate change land cover scenarios EURASIA
殡葬改革:土地、木材和金钱浪费及其讨论
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作者 陈华文 《民俗研究》 CSSCI 北大核心 2020年第1期119-127,159,共10页
殡葬改革是我国政府持续推行的一项文化和社会改革政策,旨在改善民生,而由此引发的争议则与不同地区的具体实施方式有关,并涉及对传统丧葬文化和习俗的多元认知。具体到土葬还是火化的话题而言,争议集中在土葬浪费土地资源、森林木材资... 殡葬改革是我国政府持续推行的一项文化和社会改革政策,旨在改善民生,而由此引发的争议则与不同地区的具体实施方式有关,并涉及对传统丧葬文化和习俗的多元认知。具体到土葬还是火化的话题而言,争议集中在土葬浪费土地资源、森林木材资源,以及传统仪式的铺张浪费等方面,有待于学术界进一步的讨论和厘清。与传统殡葬有关的土地占用、木材损耗、金钱浪费等现象,并非不可改进,也并非与当今社会发展难以兼顾。或许,在尊重传统文化认同的基础上,区别对待殡葬改革进程中的城乡差异,有助于多元化地解决这一问题。 展开更多
关键词 殡葬改革 土地 木材 金钱浪费 多元化
带肋板尾缘开缝叶片内的流动传热性能研究 预览
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作者 王瑞琴 晏鑫 何坤 《西安交通大学学报》 EI CAS CSCD 北大核心 2020年第1期150-161,183,共13页
针对燃气透平带肋板的尾缘开缝叶片,采用RANS(Reynolds Averaged Navier-Stokes)方程求解结合SSTγ-Reθ转换模型数值方法,研究了3种来流湍流度、3种来流雷诺数和3种冷气质量流量比条件下叶片和尾缘开缝区域的流动传热性能,并与无肋板... 针对燃气透平带肋板的尾缘开缝叶片,采用RANS(Reynolds Averaged Navier-Stokes)方程求解结合SSTγ-Reθ转换模型数值方法,研究了3种来流湍流度、3种来流雷诺数和3种冷气质量流量比条件下叶片和尾缘开缝区域的流动传热性能,并与无肋板开缝叶片进行了对比,利用实验数据考核了数值方法的有效性。计算结果表明:随着来流湍流度的增大,带肋板的尾缘开缝叶片表面传热系数逐渐增大,开缝壁面的传热系数基本不变,能量损失系数和总压损失系数随之增加;在相同来流湍流度时,增加来流雷诺数可降低损失;增大冷气质量流量比对叶片表面的传热系数影响很小,但可显著提升开缝壁面的传热系数;与无肋板的开缝叶片相比,带肋板的尾缘开缝叶片表面的传热系数和压力系数更低,开缝壁面换热系数更高;当Re为2.0×106时,带肋板的开缝壁面平均换热系数比无肋板时的高14.46%,来流雷诺数分别为0.5×106、1.0×106、2.0×106时,相比无肋板开缝叶片,带肋板尾缘开缝叶片的能量损失系数分别增加了3.75%、5.91%、6.75%,总压损失系数分别降低了3.4%、3.37%、2.06%。 展开更多
关键词 燃气透平 尾缘开缝 肋板 传热 损失
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适应性选择:传统乡村生活的内生性逻辑 预览
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作者 张浩 《原生态民族文化学刊》 CSSCI 2020年第1期75-81,共7页
马克思主义认为,决定人类社会发展变迁的根本力量是物质资料的生产方式,即生产力和生产关系。在中原传统乡村社会里,人们都过着一种基于传统农业生产的乡土生活,有着大致相同的生活习惯和思维方式,并通过人们对于乡村环境、土地、婚姻... 马克思主义认为,决定人类社会发展变迁的根本力量是物质资料的生产方式,即生产力和生产关系。在中原传统乡村社会里,人们都过着一种基于传统农业生产的乡土生活,有着大致相同的生活习惯和思维方式,并通过人们对于乡村环境、土地、婚姻、手工业等方面呈现出来,在这些看似普遍、毫无特色的乡村生活中,反映出中原乡村要想走出传统、迈向现代应当选择的方向,这也是费孝通先生长期关注并致力于加以解决的重要问题。 展开更多
关键词 传统乡村 适应性 婚姻 土地 手工艺
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Soil temperature estimation at different depths,using remotely-sensed data 预览
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作者 HUANG Ran HUANG Jian-xi +6 位作者 ZHANG Chao MA Hong-yuan ZHUO Wen CHEN Ying-yi ZHU De-hai Qingling WU Lamin R.MANSARAY 《农业科学学报:英文版》 SCIE CAS CSCD 2020年第1期277-290,共14页
Soil temperatures at different depths down the soil profile are important agro-meteorological indicators which are necessary for ecological modeling and precision agricultural activities. In this paper, using time ser... Soil temperatures at different depths down the soil profile are important agro-meteorological indicators which are necessary for ecological modeling and precision agricultural activities. In this paper, using time series of soil temperature(ST) measured at different depths(0, 5, 10, 20, and 40 cm) at agro-meteorological stations in northern China as reference data, ST was estimated from land surface temperature(LST) and normalized difference vegetation index(NDVI) derived from AQUA/TERRA MODIS data, and solar declination(Ds) in univariate and multivariate linear regression models. Results showed that when daytime LST is used as predictor, the coefficient of determination(R~2) values decrease from the 0 cm layer to the 40 cm layer. Additionally, with the use of nighttime LST as predictor, the R^2 values were relatively higher at 5, 10 and 15 cm depths than those at 0, 20 and 40 cm depths. It is further observed that the multiple linear regression models for soil temperature estimation outperform the univariate linear regression models based on the root mean squared errors(RMSEs) and R^2. These results have demonstrated the potential of MODIS data in tandem with the Ds parameter for soil temperature estimation at the upper layers of the soil profile where plant roots grow in. To the best of our knowledge, this is the first attempt at the synergistic use of LST, NDVI and Ds for soil temperature estimation at different depths of the upper layers of the soil profile, representing a significant contribution to soil remote sensing. 展开更多
关键词 soil temperature land surface temperature normalized difference vegetation index solar declination
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土地工程及其在农牧交错区可持续农业中的作用——以陕西省榆林市为例(英文)
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作者 WU Wenhao CHEN Zongfeng +3 位作者 LI Yuheng WANG Yongsheng YAN Jiayu SONG Chuanyao 《地理学报:英文版》 SCIE CSCD 2019年第5期818-830,共13页
With global climate change, the agricultural light-temperature potential productivity in the agro-pastoral ecotone has increased. This offers a good opportunity to develop agriculture in the agro-pastoral ecotone. How... With global climate change, the agricultural light-temperature potential productivity in the agro-pastoral ecotone has increased. This offers a good opportunity to develop agriculture in the agro-pastoral ecotone. However, the agro-pastoral ecotone is also an ecologically fragile area in which land degradation challenges agricultural development. As population grows and the need for food increases, the land carrying capacity of the agro-pastoral ecotone becomes insufficient, and the human–land relationship is not harmonious. Such conditions have limited the agricultural and rural development in the ecotone. The paper demonstrates how land engineering may improve land quality and support agricultural development in the ecotone based on studies at a research station established in 2015 in Yulin,Shaanxi Province, China. The studies target three factors: soil improvement, crop selection,and field management. The results show that:(1) The highest yield of crops planted on improved land is close to or even higher than that achieved under previous crop growth conditions. For instance, the corn yields can exceed 25%.(2) The potatoes grown on the improved land yield the highest gross income, reaching 67,200 yuan/ha. By way of land engineering,input costs can be balanced in 3–5 years.(3) As a result of land engineering, some villages in Yulin City have realized sustainable agricultural and even rural development, and promotion of this model will support the sustainable development of agriculture in the agro-pastoral ecotone. 展开更多
关键词 agro-pastoral ECOTONE LAND engineering degraded LAND CONSOLIDATION human–land relationship sustainability
以地租的视角探究土地扶贫政策 预览
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作者 苏昌强 《当代农村财经》 2019年第5期5-13,共9页
以时空为线索,研究土地地租对三农的意义。通过归纳土地流转类型,归纳土地政策演变,提出土地研究的意义。农民的最大的财富就是土地,在没有流通前,在现行土地政策下,大量农村土地作为隐性的资产,同时也限制农民发家致富的可能性。面对... 以时空为线索,研究土地地租对三农的意义。通过归纳土地流转类型,归纳土地政策演变,提出土地研究的意义。农民的最大的财富就是土地,在没有流通前,在现行土地政策下,大量农村土地作为隐性的资产,同时也限制农民发家致富的可能性。面对农村现代化的要求,只有在土地地租上做文章,农民有可能致富,才有可能摆脱贫困。通过新时代的土地扶贫的研究,吹响农村发展打开土地承包权的“二次”革命。结合乡村振兴,对农业用地加强现代农业的帮扶力度。农村建设用地可以参与城市建设带来的帮扶福利。 展开更多
关键词 土地 扶贫 地租 政策
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Review on simulation of land-surface processes on the Tibetan Plateau 预览
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作者 Rui Chen MeiXue Yang +1 位作者 XueJia Wang GuoNing Wan 《寒旱区科学:英文版》 CSCD 2019年第2期93-115,共23页
The Tibetan Plateau (TP) has powerful dynamics and thermal effects, which makes the interaction between its land and atmosphere significantly affect climate and environment in the regional or global area. By retrospec... The Tibetan Plateau (TP) has powerful dynamics and thermal effects, which makes the interaction between its land and atmosphere significantly affect climate and environment in the regional or global area. By retrospecting the latest research progress in the simulation of land-surface processes (LSPs) over the past 20 years, this study discusses both the simulation ability of land-surface models (LSMs) and the modification of parameterization schemes from two perspectives, the models' applicability and improved parameterization schemes. Our review suggests that different LSMs can well capture the spatiotemporal variations of the physical quantities of LSPs;but none of them can be fully applied to the plateau, meaning that all need to be revised according to the characteristics specific to the TP. Avoiding the unstable iterative computation and determining the freeze?thaw critical temperature according to the thermodynamic equilibrium equation, the unreasonable freeze?thaw parameterization scheme can be improved. Due to the complex underlying surface of the TP, no parameterization scheme of roughness length can well simulate the various characteristics of the turbulent flux over the TP at different temporal scales. The uniform soil thermodynamic and hydraulic parameterization scheme is unreasonable when it is applied to the plateau, as a result of the strong soil heterogeneity. There is little research on the snow-cover process so far, and the improved scheme has no advantage over the original one due to the lack of some related physical processes. The constant interaction among subprocesses of LSPs makes the improvement of a multiparameterization scheme yield better simulation results. According to the review of existing research, adding high-quality observation stations, developing a parameterization scheme suitable for the special LSPs of the TP, and adjusting the model structures can be helpful to the simulation of LSPs on the TP. 展开更多
关键词 TIBETAN PLATEAU land - ATMOSPHERE interaction LAND-SURFACE models model APPLICABILITY parameterized MODIFICATION
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How Can Chinese Farmers' Property Income Be Improved?A Population-Land Coupling Urbanization Mechanism
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作者 Yuzhe Wu Wendan Jiang +2 位作者 Jiaojiao Luo Xiaoling Zhang Martin Skitmore 《中国与世界经济:英文版》 2019年第2期107-126,共20页
Balancing urban and rural development is an important political goal in China.The failure of rural land privatization has led to a low level of rural economic development and a vast property income gap between citizen... Balancing urban and rural development is an important political goal in China.The failure of rural land privatization has led to a low level of rural economic development and a vast property income gap between citizens and farmers.This paper illustrates the reasons for property income inequality from the perspective of the land tenure system and the dualistic household registration system.After evaluating the segmentation of the rural land market and the rigid nature of rural land assets,a population-land coupling urbanization mechanism is proposed.The paper argues that China s land property system has externalized a high degree of geospatial and social urban and rural intertwinement.Major reform of the rural land property rights system is required to correct the situation(further development of the social security system and stable urbanization)and to increase property income potential for farmers. 展开更多
关键词 household REGISTRATION system LAND OWNERSHIP LAND PRIVATIZATION property INCOME
Regional and Global Land Data Assimilation Systems: Innovations,Challenges, and Prospects
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作者 Youlong XIA Zengchao HAO +5 位作者 Chunxiang SHI Yaohui LI Jesse MENG Tongren XU Xinying WU Baoqing ZHANG 《气象学报:英文版》 SCIE CSCD 2019年第2期159-189,共31页
Since the North American and Global Land Data Assimilation Systems(NLDAS and GLDAS) were established in2004, significant progress has been made in development of regional and global LDASs. National, regional, projectb... Since the North American and Global Land Data Assimilation Systems(NLDAS and GLDAS) were established in2004, significant progress has been made in development of regional and global LDASs. National, regional, projectbased, and global LDASs are widely developed across the world. This paper summarizes and overviews the development, current status, applications, challenges, and future prospects of these LDASs. We first introduce various regional and global LDASs including their development history and innovations, and then discuss the evaluation, validation, and applications(from numerical model prediction to water resources management) of these LDASs. More importantly, we document in detail some specific challenges that the LDASs are facing: quality of the in-situ observations, satellite retrievals, reanalysis data, surface meteorological forcing data, and soil and vegetation databases;land surface model physical process treatment and parameter calibration;land data assimilation difficulties;and spatial scale incompatibility problems. Finally, some prospects such as the use of land information system software, the unified global LDAS system with nesting concept and hyper-resolution, and uncertainty estimates for model structure,parameters, and forcing are discussed. 展开更多
关键词 LAND data ASSIMILATION system (LDAS) REGIONAL and GLOBAL LDASs in-situ observation satellite RETRIEVAL LAND surface model (LSM)
Land Coordination Analysis and Planning Strategy Suggestions in Northeast China Under the Spatial Planning Transition
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作者 Guo Rong Huang Mengshi 《城市规划:英文版》 CSCD 2019年第2期6-16,共11页
Facing the new era of construction of socialism with Chinese characteristics, it is critical for the northeastern region of China to hold this new chance for its overall revitalization.The foundation and key of this r... Facing the new era of construction of socialism with Chinese characteristics, it is critical for the northeastern region of China to hold this new chance for its overall revitalization.The foundation and key of this revitalization lie in finding out problems in the urban development and then putting forward feasible countermeasures.This paper studies 34 prefecture-level cities in northeast China, and uses the coordination index to analyze the relationship between land and population, economy, and investment, of different types of cities in the region from 2000 – 2014, in order to discover problems in its urban development and provide planning countermeasures.Data shows that in northeast China, the imbalance between urban land expansion and population is significant, the imbalance between urban land use and either economic development or capital investment is periodical, for which the primary reasons include strong centralization effect of center cities, limited input on land resources, and weak industrial competitiveness.Correspondingly, the paper proposes planning strategies in terms of vitalizing stock land, enriching land use functions, and coordinating industrial resources, with an expectation of providing both the theoretical foundation for the economic revival in the northeastern region and a guidance on practice of revitalization strategies in all cities of the region. 展开更多
关键词 LAND coordination urban LAND expansion population SHRINKAGE PLANNING STRATEGY NORTHEAST China
土地资源配置与经济增长的相互关系 预览
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作者 周琰 汪志红 +2 位作者 龚琦 夏娟 梅焕 《湖北农业科学》 2019年第S1期25-29,共5页
土地是社会经济发展中的重要元素,研究土地参与经济增长配置具有提升土地经济效率的重要作用。通过对土地资源配置的理论研究回溯,以及对后续土地参与经济增长、土地配置建模研究的综合评述,发现土地作为经济要素配置参与经济增长的理... 土地是社会经济发展中的重要元素,研究土地参与经济增长配置具有提升土地经济效率的重要作用。通过对土地资源配置的理论研究回溯,以及对后续土地参与经济增长、土地配置建模研究的综合评述,发现土地作为经济要素配置参与经济增长的理论、模型比较成熟,可以运用到区域经济的研究,可作为研究提升土地在经济发展中的配置效率的借鉴和工具。 展开更多
关键词 土地 资源配置 经济增长 土地经济效率 区域经济
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Origin and advances in implementing blowing-snow effects in the Community Land Model 预览
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作者 ZeYong Hu ZhiPeng Xie 《寒旱区科学:英文版》 CSCD 2019年第5期335-339,共5页
Snow cover on the Tibetan Plateau(TP)is closely related to regional and continental biological and hydrological processes.The vast snow cover,special climatic conditions,and sparse vegetative cover over the TP facilit... Snow cover on the Tibetan Plateau(TP)is closely related to regional and continental biological and hydrological processes.The vast snow cover,special climatic conditions,and sparse vegetative cover over the TP facilitate the occurrence of blowing snow,leading to substantial heterogeneities in the snow cover and great promotion in the moisture supply from the land surface to the overlying atmospheric boundary layer.However,blowing-snow processes are significantly misrepresented or even neglected in current models,which causes considerable uncertainties of numerical model simulations and leads to erroneous estimates of snow-related processes in mountainous terrain.We present in this paper a brief review of our work in the past 5 years to serve as a basis for further development and improvement of the land-surface model.These studies can be divided into three parts:detection of the problems,development of the land-surface model,and application of the coupled model over the TP(the logical framework is presented in Figure 1).The origin and advances in the development of a land-surface model with consideration of blowing-snow effects are described herein;and the importance of blowing-snow processes in the land-surface model,especially over the TP,is highlighted.We expect that the blowingsnow studies over the TP will play a key role in documenting and understanding the land-surface processes(LSPs)and the cryospheric changes over the TP. 展开更多
关键词 BLOWING SNOW LAND surface process COMMUNITY LAND MODEL Tibetan Plateau
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