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Measuring the Floor Area of Buildings:Problems of Consistency and a Solution 预览
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作者 Dario Trabucco William Douglas Miranda 《土木工程与建筑:英文版》 2019年第2期107-114,共8页
Measuring the floor area of a building may seem a straightforward activity,but it is not.What to be included and what to be considered vary in virtually every country,and definitions such as GFA(gross floor area),NRA(... Measuring the floor area of a building may seem a straightforward activity,but it is not.What to be included and what to be considered vary in virtually every country,and definitions such as GFA(gross floor area),NRA(net rentable area),etc.are also misleading as they are not consistent.In an era in which international actors contribute for projects in all major cities,having a consistent system to measure the floor area of a building is of the utmost importance.Consistent measurements allow not just for easier and better design,but also for the comparison of buildings,as the floor area is the nominator of all parameters of sustainability,energy consumption,construction cost,occupancy ratios,cleaning fees,etc. 展开更多
关键词 FLOOR area measurement GROSS area net area INTERNAL DOMINANT FACE
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Re-assessing Vegetation Carbon Storage and Emissions from Land Use Change in China Using Surface Area 预览
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作者 HE Qingsong TAN Shukui +2 位作者 XIE Peng LIU Yaolin LI Jing 《中国地理科学:英文版》 SCIE CSCD 2019年第4期601-613,共13页
Land surface area estimation can provide basic information for accurately estimating vegetation carbon storage under complex terrain. This study selected China, a country dominated by mountains, as an example, and cal... Land surface area estimation can provide basic information for accurately estimating vegetation carbon storage under complex terrain. This study selected China, a country dominated by mountains, as an example, and calculated terrestrial vegetation carbon storage(VCS) for 2000 and 2015 using land surface area and traditional ellipsoid area. The land surface area is estimated by a triangular network on the high precision digital elevation model.The results showed that: 1) The VCS estimated by the surface area measurement in 2000 and 2015 were 0.676 and0.692 Pg C(1 Pg = 1015 g) higher than the VCS calculated using the ellipsoid area, respectively. 2) As the elevation increases, the differences between VCS estimated by surface area measurement and ellipsoid area measurement are expanding. Specially, a clear gap was present starting from an elevation of 500 m, with the relative error exceeds8.99%. 3) The total amount of carbon emitted due to land use change reached 0.114 Pg C. The conversions of forestland and grassland to other land use type are the main reasons of the loss of vegetation carbon storage, resulting in a total amount of biomass carbon storage decreased by 0.942 and 0.111 Pg C, respectively. This study was a preliminary exploration of incorporating land surface area as a factor in resource estimation, which can help more accurately understand the status of resources and the environment in the region. 展开更多
关键词 carbon storage LAND use CHANGE surface area RESOURCE estimation ellipsoidal area China
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基于片区的南京市住宅用地价格时空格局研究 预览
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作者 刘玉轩 于丙辰 +1 位作者 徐海洋 陈刚 《地理空间信息》 2019年第3期94-96,119,I0010共5页
针对以行政区划为研究单元不能合理直观表现土地价格时空格局的问题,以南京市为例,以片区为研究单元,根据2005~2016年南京市的住宅土地出让数据,运用GIS方法,分析了南京市住宅地价的时空分布格局。结果表明,参照经济、人文等因素进行片... 针对以行政区划为研究单元不能合理直观表现土地价格时空格局的问题,以南京市为例,以片区为研究单元,根据2005~2016年南京市的住宅土地出让数据,运用GIS方法,分析了南京市住宅地价的时空分布格局。结果表明,参照经济、人文等因素进行片区划分;河西板块为地价最高点,插值结果与片区划分一致;市中心呈地价高-高相关特征,热点分析、空间自相关分析与实际一致。因此,以片区为研究单元可以较好地探索南京市住宅用地价格的时空格局。 展开更多
关键词 片区 行政区 住宅用地 时空格局 南京市
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Spatial-temporal variations of natural suitability of human settlement environment in the Three Gorges Reservoir Area A case study in Fengjie County,China
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作者 Jieqiong LUO Tinggang ZHOU +1 位作者 Peijun DU Zhigang XU 《地球科学前沿:英文版》 SCIE CAS CSCD 2019年第1期1-17,共17页
With rapid environmental degeneration and socio-economie development,the human settlement environment (HSE)has experienced dramatic changes and attracted attention from different communities.Consequently,the spatial-t... With rapid environmental degeneration and socio-economie development,the human settlement environment (HSE)has experienced dramatic changes and attracted attention from different communities.Consequently,the spatial-temporal evaluation of natural suitability of the human settlement environment (NSHSE)has become essential for understanding the patterns and dynamics of HSE,and for coordinating sustainable development among regional populations,resources,and environments.This study aims to explore the spatialtemporal evolution of NSHSE patterns in 1997,2005,and 2009 in Fengjie County near the Three Gorges Reservoir Area (TGRA).A spatially weighted NSHSE model was established by integrating multi-source data (e.g.,census data,meteorological data,remote sensing images,DEM data,and GIS data)into one framework,where the Ordinary Least Squares (OLS)linear regression model was applied to calculate the weights of indices in the NSHSE model.Results show that the trend of natural suitability has been first downward and then upward, which is evidenced by the disparity of NSHSE existing in the south,north,and central areas of Fengjie County. Results also reveal clustered NSHSE patterns for all 30 townships.Meanwhile,NSHSE has significant influence on population distribution,and 71.49% of the total population is living in moderate and high suitable districts. 展开更多
关键词 NATURAL SUITABILITY of human SETTLEMENT ENVIRONMENT ordinary least SQUARES model global and local spatial AUTOCORRELATION analyses Three Gorges Reservoir Area (TGRA) Fengjie Cotmty
Review of China's policy and management system for the paid use of sea area Feng 预览
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作者 Feng Li Zenglei Xi Xiangbo Liang 《中国人口资源与环境:英文版》 2019年第1期58-66,共9页
As a carrier to develop various marine resources, sea area is regulated as a kind of important resources through legislation by many coastal countries with a management system for the paid use of sea area. Since the e... As a carrier to develop various marine resources, sea area is regulated as a kind of important resources through legislation by many coastal countries with a management system for the paid use of sea area. Since the early 1990s, China has begun to implement the paid use and formed an institutional system comprised of three levels after developing it for more than two decades. From 2002 to 2015, the Chinese Government transferred the use right of sea area of 33,910 km2 by paid use and levied a total of 75.89 billion CNY (11.328 billion US dollars) of sea area use payment. Apart from this, the Government has gained rich experience in operating and managing the compensable use of sea area. After retrospectively analyzing the development history of paid use of China’s sea area, the research presents an institutional structure and the implementation of the management system for the paid use of sea area and the main problems therein. On this basis, management policies and feasible policy suggestions are proposed. Research results from this study can provide available references for other developing countries and emerging economies to apply and improve native management system for the paid use of sea area. 展开更多
关键词 PAID use SEA area POLICY MANAGEMENT system China
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青藏高原边界地区天然水的水化学性质及其成因
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作者 田原 余成群 +2 位作者 查欣洁 高星 戴尔阜 《地理学报:英文版》 SCIE CSCD 2019年第11期1876-1894,共19页
The special geography and human environment of the Qinghai-Tibet Plateau has created the unique hydrochemical characteristics of the region’s natural water,which has been preserved in a largely natural state.However,... The special geography and human environment of the Qinghai-Tibet Plateau has created the unique hydrochemical characteristics of the region’s natural water,which has been preserved in a largely natural state.However,as the intensity of anthropogenic activities in the region has continued to increase,the water environment and hydrochemical characteristics of the Qinghai-Tibet Plateau have altered.In this study,water samples from the western,southern,and northeastern border areas of the Qinghai-Tibet Plateau,where human activities are ongoing,were collected,analyzed,and measured.The regional differences and factors controlling them were also investigated.The key results were obtained as follows.(1) Differences in the physical properties and hydrochemical characteristics,and their controlling factors,occurred in the different boundary areas of the Qinghai-Tibet Plateau.These differences were mainly the consequence of the geographical environment and geological conditions.(2) The water quality was good and suitable for drinking,with most samples meeting GB (Chinese national) and WHO (World Health Organization) drinking water standards.(3) The chemical properties of water were mainly controlled by the weathering of carbonates and the dissolution of evaporative rocks,with the former the most influential.(4) The biological quality indicators of natural water in the border areas were far superior to GB and WHO drinking water standards. 展开更多
关键词 BORDER area of the Qinghai-Tibet PLATEAU NATURAL WATER hydrochemical characteristics controlling FACTORS
Inter-provincial Differences in Rice Multi-cropping Changes in Main Double-cropping Rice Area in China: Evidence from Provinces and Households 预览
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作者 WANG Renjing LI Xiubin +4 位作者 TAN Minghong XIN Liangjie WANG Xue WANG Yahui JIANG Min 《中国地理科学:英文版》 SCIE CSCD 2019年第1期127-138,共12页
Since the early 1980 s, the multi-cropping index for rice has decreased significantly in main double-cropping rice area in China, which is the primary double-cropping rice(DCR) production area. This decline may bring ... Since the early 1980 s, the multi-cropping index for rice has decreased significantly in main double-cropping rice area in China, which is the primary double-cropping rice(DCR) production area. This decline may bring challenges to food security in China because rice is the staple food for more than 60% of the Chinese population. It has been generally recognized that rapidly rising labor costs due to economic growth and urbanization in China is the key driving force of the ‘double-to-single’ rice cropping system adaption. However, not all provinces have shown a dramatic decline in DCR area, and labor costs alone cannot explain this difference. To elucidate the reasons for these inter-provincial distinctions and the dynamics of rice cropping system adaption, we evaluated the influencing factors using provincial panel data from 1980 to 2015. We also used household survey data for empirical analysis to explore the mechanisms driving differences in rice multi-cropping changes. Our results indicated that the eight provinces in the study can be divided into three spatial groups based on the extent of DCR area decline, the rapidly-declining marginal, core, and stable zones. Increasing labor cost due to rapid urbanization was the key driving force of rice cropping system adaption, but the land use dynamic vary hugely among different provinces. These differences between zones were due to the interaction between labor price and accumulated temperature conditions. Therefore, increasing labor costs had the greatest impact in Zhejiang, Anhui, and Hubei, where the accumulated temperature is relatively low and rice multi-cropping index declined dramaticly. However, labor costs had little impact in Guangdong and Guangxi. Differences in accumulated temperature conditions resulted in spatially different labor demands and pressure on households during the busy season. As a result, there have been different profits and rice multi-cropping changes between provinces and zones. Because of these spatial differences, regionally approp 展开更多
关键词 multi-cropping change INTER-PROVINCIAL DIFFERENCES cropping system adaption accumulated temperature double-cropping RICE area China
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Effect of Climate Change on Yield of Winter Wheat in Jiangsu Province 预览
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作者 Shun SHANG Xuhui ZHANG +1 位作者 Zhaotang SHANG Jing WU 《农业生物技术:英文版》 CAS 2019年第1期224-229,234共7页
The spike-grain structure and yield data of winter wheat observed at 10 winter wheat observation stations in Jiangsu agrometeorological observation stations in the China Meteorological Observation Network were used to... The spike-grain structure and yield data of winter wheat observed at 10 winter wheat observation stations in Jiangsu agrometeorological observation stations in the China Meteorological Observation Network were used to design the assessment model and evaluation criteria of the effects of climate change on spike-grain structure and yield of winter wheat.The linear regression method was used to determine the parameters of the assessment model,and the climate fact extrapolation method was used to determine future climate change scenarios.The effects of climate change on spike-grain structure and yield of winter wheat in Jiangsu Province were calculated and analyzed finally.The results showed that with the climate change,the meteorological conditions during the growth and development of winter wheat changed,which caused the number of effective spikes to decrease,and the number of grains per spike and thousand-grain weight to increase,and this new type of spike-grain structure combination was beneficial to the increase of the unit yield of winter wheat.The variations of meteorological elements caused by climate change during winter wheat growth and development had different effects on spike-grain structure at different growth stages.The spike-grain structure had an"increasing-decreasing"periodic variation with the growth period overall,with a period of one to three stages.The relationship between winter wheat growth and development and meteorological conditions can be adjusted in real time through stress-resistant cultivation techniques to achieve the high-yield and high-quality cultivation target of winter wheat production. 展开更多
关键词 YIELD PER unit area Spike-grain structure Climate assessment
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Poverty Alleviation in the Poor Mountainous Areas of Western China by Supporting Industry : A Case Study of Xundian Hui and Yi Autonomous County in Yunnan Province 预览
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作者 Bosheng ZHANG Zisheng YANG 《亚洲农业研究:英文版》 2019年第7期51-54,62共5页
Poverty alleviation by supporting industry is a key measure to promote the poverty alleviation of relocated households. Taking Xundian County, the first county in Yunnan Province that has been lifted out of poverty, a... Poverty alleviation by supporting industry is a key measure to promote the poverty alleviation of relocated households. Taking Xundian County, the first county in Yunnan Province that has been lifted out of poverty, as an research case, this article analyzes and summarizes the industry-supporting poverty alleviation achievements and successful experience of two typical relocation areas (Shanhou Village and Eyang Village) in Xundian County. Practice has shown that the key to industry-supporting poverty alleviation lies in targetedness to strengthen the participation of poor farmers in industrial development. The interests of poverty alleviation entities should be linked by market mechanism to establish a benign interaction between all parties for win-win situation, thereby effectively guaranteeing the long-term and healthy development of poverty alleviation by supporting industry. 展开更多
关键词 Poverty-stricken mountainous area Targeted poverty alleviation by SUPPORTING INDUSTRY Relocation Model Interest linkage Xundian HUI and YI AUTONOMOUS COUNTY
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Reservoir Prediction Restricted by Sequence Stratigraphy--A Case Study of Bioclastic Shoal Reservoir in Changxing Formation of Jiannan Area 预览
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作者 Ningnan Wu 《长江油气(英文版)》 2019年第1期1-11,共11页
Bioclastic shoal reservoir in Changxing Formation of Jiannan area is characterized by small thickness and strong heterogeneity. The uncertainty of the reservoir distribution pattern has confined the effective developm... Bioclastic shoal reservoir in Changxing Formation of Jiannan area is characterized by small thickness and strong heterogeneity. The uncertainty of the reservoir distribution pattern has confined the effective development of this area, so the accurate bioclastic shoal reservoir prediction would be the key to achieve development breakthroughs. Based on drilling, well-log, seismic and core analysis data, this article conducted exquisite sequence stratigraphic classification and established isochronal regional stratigraphic framework of Changxing Formation in Jiannan area. The reservoir seismic corresponding features were determined by exquisite calibrating bioclastic shoal reservoir in Changxing Formation. Therefore, seismic processing methods, such as multiple attribute analysis and amplitude inversion, were applied to attain more reliable reservoir prediction results, which indicated the distribution of vertical reservoir in SSQ2, the IV sequence order and the distribution of horizontal reservoir around Well J43 and JZ1 in the platform margin of the study area. 展开更多
关键词 Bioclastic SHOAL SEQUENCE STRATIGRAPHIC Classification RESERVOIR Prediction Changxing Formation Jiannan Area
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Undrained shear strength evaluation for hydrate-bearing sediment overlying strata in the Shenhu area, northern South China Sea 预览
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作者 Yanlong Li Gaowei Hu +3 位作者 Nengyou Wu Changling Liu Qiang Chen Chen’an Li 《海洋学报:英文版》 SCIE CAS CSCD 2019年第3期114-123,共10页
The undrained shear strength of shallow strata is a critical parameter for safety design in deep-water operations.In situ piezocone penetration tests(CPTU) and laboratory experiments are performed at Site W18-19 in th... The undrained shear strength of shallow strata is a critical parameter for safety design in deep-water operations.In situ piezocone penetration tests(CPTU) and laboratory experiments are performed at Site W18-19 in the Shenhu area, northern South China Sea, where China’s first marine hydrate exploitation operation is due to be located. The validation of the undrained shear strength prediction model based on CPTU parameters. Different laboratory tests, including pocket penetrometer, torvane, miniature vane and unconsolidated undrained triaxial tests, are employed to solve empirical cone coefficients by statistical and mathematical methods. Finally, an optimized model is proposed to describe the longitudinal distribution of undrained shear strength in calcareous clay strata in the Shenhu area. Research results reveal that average empirical cone coefficients based on total cone resistance, effective resistance, and excess-pore pressure are 13.8, 4.2 and 14.4, respectively. The undrained shear strength prediction model shows a good fit with the laboratory results only within specific intervals based on their compaction degree and gas-bearing conditions. The optimized prediction model in piecewise function format can be used to describe the longitudinal distribution of the undrained shear strength for calcareous clay within all depth intervals from the mud-line to the upper boundary of hydrate-bearing sediments(HBS). The optimized prediction result indicates that the effective cone resistance model is suitable for very soft to firm calcareous clays,the excess-pore pressure model can depict the undrained shear strength for firm to very stiff but gas-free clays,while the total cone resistance model is advantageous for evaluating the undrained shear strength for very stiff and gassy clays. The optimized model in piecewise function format can considerably improve the adaptability of empirical models for calcareous clay in the Shenhu area. These results are significant for safety evaluations of proposed hydrate exploitat 展开更多
关键词 piezocone penetration TEST HYDRATE EXPLOITATION TEST UNDRAINED shear strength CALCAREOUS clay Shenhu area South China Sea
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Spatiotemporal features of farmland scaling and the mechanisms that underlie these changes within the Three Gorges Reservoir Area
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作者 LIANG Xinyuan LI Yangbing 《地理学报:英文版》 SCIE CSCD 2019年第4期563-580,共18页
Discussions regarding the functional transformation of agricultural utilization and the mechanisms that underlie these changes within the Three Gorges Reservoir Area(TGRA)reflect variati ons in the relati on ship betw... Discussions regarding the functional transformation of agricultural utilization and the mechanisms that underlie these changes within the Three Gorges Reservoir Area(TGRA)reflect variati ons in the relati on ship betwee n people and their environme nt in China's central and wester ns part,an area of mountains and reservoirs.A clear understa nding of these changes also provides the scientific basis for the development of multi-functional agriculture in typical mountainous areas.Five counties were selected for analysis in this study from the hinterland of the TGRA;we analyzed changes in farmland scaling and corresponding under?lying mechanisms by defining the concepts of“Scaling Farmland”(SF)and by using the software packages ArcGIS10.2,SPSS,and Geographical Detectors.The results of this analysis show that sources of increased SF have mainly comprised cultivated and shrub land.In deed,with the excepti on of some alpine off-season vegetables,SF growth has mainly occurred in low altitude areas and in places where the slope is less than 30°.We also show that spatial changes in various SF types have also been substantially different,but in all cases are closely related to road and township administrative centers.Natural factors at the patch level,including elevation and slope,have contributed significantly to SF,while at the township level,underlying socioeconomic and humanistic factors have tended to include road traffic and agricultural population density.In contrast,at the region al level,underlying driving forces within each have tended to be more significant than overall study area scale.We show that while changes in,and the development of,SF have been driven by numerous factors,agri?cultural policies have always been amongst the most important.The results clearly elucidate general land use transformation patter ns within the mountain regi ons of western China. 展开更多
关键词 Three Gorges Reservoir Area functional transformation of agricultural land SCALING FARMLAND SPATIOTEMPORAL FEATURES UNDERLYING driving FORCES
Grading evaluation and prediction of fracture-cavity reservoirs in Cambrian Longwangmiao Formation of Moxi area,Sichuan Basin,SW China 预览
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作者 WANG Bei LIU Xiangjun SIMA Liqiang 《石油勘探与开发:英文版》 2019年第2期301-313,共13页
By using core, thin section, well logging, seismic, well testing and other data, the reservoir grading evaluation parameters were selected, the classification criterion considering multiple factors for carbonate reser... By using core, thin section, well logging, seismic, well testing and other data, the reservoir grading evaluation parameters were selected, the classification criterion considering multiple factors for carbonate reservoirs in this area were established, and the main factors affecting the development of high quality reservoir were determined. By employing Formation MicroScanner Image(FMI) logging fracture-cavity recognition technology and reservoir seismic waveform classification technology, the spatial distribution of reservoirs of all grades were predicted. On the basis of identifying four types of reservoir space developed in the study area by mercury injection experiment, a classification criterion was established using four reservoir grading evaluation parameters, median throat radius, effective porosity and effective permeability of fracture-cavity development zone, relationship between fracture and dissolution pore development and assemblage, and the reservoirs in the study area were classified into grade I high quality reservoir of fracture and cavity type, grade II average reservoir of fracture and porosity type, grade Ⅲ poor reservoir of intergranular pore type. Based on the three main factors controlling the development of high quality reservoir, structural location, sedimentary facies and epigenesis, the distribution of the 3 grades reservoirs in each well area and formation were predicted using geophysical response and percolation characteristics. Follow-up drilling has confirmed that the classification evaluation standard and prediction methods established are effective. 展开更多
关键词 Sichuan Basin Moxi area CAMBRIAN Longwangmiao Formation carbonate rock FRACTURE-CAVITY RESERVOIR RESERVOIR GRADING EVALUATION RESERVOIR PREDICTION
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Topographical relief characteristics and its impact on population and economy:A case study of the mountainous area in western Henan,China
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作者 ZHANG Jingjing ZHU Wenbo +3 位作者 ZHU Lianqi CUI Yaoping HE Shasha REN Han 《地理学报:英文版》 SCIE CSCD 2019年第4期598-612,共15页
Topographical relief is a key factor that limits population distribution and economic development in mountainous areas.The limitation is especially apparent in the mountain?plain t「ansition zone.Taking the transition... Topographical relief is a key factor that limits population distribution and economic development in mountainous areas.The limitation is especially apparent in the mountain?plain t「ansition zone.Taking the transition zone between the Qinling Mountains and the North China Plain(i.e.the mountainous area in western Henan Province)as an example and based on the 200-m resolution DEM data,we used the mean change-point analysis to determine the optimal statistical unit for topographical relief,and thereafter extracted the relief degree.Taking the 1:100,000 land use data,township population and county-level industrial data,population and economic spatial models were constructed,and 200?m resolution grid population and economic density maps were gen erated.Afterwards,statistical analysis was carried out to quantitatively reveal the impact of topographical relief on population and economy.In addition,the impacts of other topographical factors were discussed.The results showed the following.(1)The relief degree in western Henan is generally low,where 58.6%of the regional topography does not exceed half the height of a reference mountain(relative elevation W250 m).Spatially,the relief degree is high in the west while low in the east,and high in the middle while low in the north and south.There is a positive correlation between relief degree and elevation,and a much stronger correlation between relief degree and slope.(2)The linear fitting degree between the population and economic validation data and the corresponding simulation data are 0.943 and 0.909,respectively,indicating that the spatialized results can reflect the actual population and economic distribution.(3)The impact of topographical relief on population and economy was stronger than that of other topographical factors.The relief degree showed a good logarithmic fit relati on ship with population density(0.911)and economic density(0.874).Specifically,88.65%of the population lives in areas where the topographical relief is W0.5 and 88.03%of the gross regional pro 展开更多
关键词 topographical RELIEF POPULATION and ECONOMY land use SPATIALIZATION grid WESTERN HENAN mountainous area
Depth Distribution Pattern of Soil Organic Carbon in Forest from Taowan Basin of Funiu Mountain Area 预览
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作者 Xifeng NING Lina SONG Yaowu TIAN 《亚洲农业研究:英文版》 2019年第6期20-24,共5页
[Objectives]By testing applicability of SOC depth distribution model in geographical and climatic conditions of Funiu Mountain area,SOC depth distribution model in the region was established and applied. The construct... [Objectives]By testing applicability of SOC depth distribution model in geographical and climatic conditions of Funiu Mountain area,SOC depth distribution model in the region was established and applied. The constructed model was used to estimate SOC mass density in other regions,thereby obtaining SOC abundance distribution chart at different depths.[Methods]165 soil sampling sites were selected from Quercus variabilis forest,Pinus tabulaeformis forest,mixed forest,and shrub forest in Taowan basin of Funiu Mountain area,to determine SOC content at different depths,study SOC depth distribution pattern of forest in Taowan basin of Funiu Mountain area,and assess SOC reserve at different depths.[Results]Average SOC density of Q. variabilis forest,P. tabulaeformis forest,mixed forest,and shrub forest at the depth of 0-20 cm was 7. 92,8. 42,8. 14 and 9. 67 kg/m~2,and there was significant difference in SOC density between shrub forest and Q. variabilis forest,P. tabulaeformis forest,mixed forest( P < 0. 05),and SOC density of four kinds of vegetation all abruptly declined with soil depth increased. At the depth of 0-20 cm,correlation between SOC density and vegetation type,canopy density,clay content and sand content was significant,and the correlation with altitude was insignificant. When carbon density at the depth of 0-100 cm was used to describe regional SOC reserve,the estimated value was lower. The established space model could predict SOC density of forest.[Conclusions]The estimation of deep-layer SOC by the established model needed further consideration,and estimation method for special areas needed to be further demonstrated. 展开更多
关键词 Funiu MOUNTAIN Area Taowan BASIN FOREST Soil ORGANIC carbon DEPTH distribution
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Discussion on“Effects of lime addition on geotechnical properties of sedimentary soil in Curitiba,Brazil”[J Rock Mech Geotech Eng 10(2018)188e194] 预览
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作者 Amin Soltani Mehdi Mirzababaei 《岩石力学与岩土工程学报:英文版》 CSCD 2019年第1期214-218,共5页
The present discussion aims at complementing the original work published by Baldovino et al.(2018)by outlining a novel point of view.In light of the inherent limitations associated with the empirical model suggested i... The present discussion aims at complementing the original work published by Baldovino et al.(2018)by outlining a novel point of view.In light of the inherent limitations associated with the empirical model suggested in the original article,the dimensional analysis technique was introduced to the soil-lime strength problem,thereby leading to the development of simple and physically meaningful dimensional models capable of predicting the unconfined compressive and splitting tensile strengths of compacted soil-lime mixtures as a function of the mixture’s index properties,i.e.lime content,initial placement(or compaction)condition,initial specific surface area and curing time.The predictive capacity of the proposed dimensional models was examined and validated by statistical techniques.The proposed dimensional models contain a limited number of fitting parameters,which can be calibrated by minimal experimental effort and hence implemented for predictive purposes. 展开更多
关键词 Dimensional analysis LIME content CURING time Specific surface area Unconfined compressive STRENGTH SPLITTING tensile STRENGTH
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基于Landsat8-OLI遥感影像水稻种植区提取方法研究 预览
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作者 李孟倩 苏世宗 《华北理工大学学报:自然科学版》 CAS 2019年第3期26-33,59共9页
以河北省唐山市曹妃甸区水稻种植面积作为研究对象,采用监督分类、支持向量机、面向对象和基于CART决策树分类法4种方法提取研究区域水稻面积。以Landsat8_OLI遥感影像作为数据源,运用ENVI5.1的软件平台,根据目视解译、水稻光谱特征和... 以河北省唐山市曹妃甸区水稻种植面积作为研究对象,采用监督分类、支持向量机、面向对象和基于CART决策树分类法4种方法提取研究区域水稻面积。以Landsat8_OLI遥感影像作为数据源,运用ENVI5.1的软件平台,根据目视解译、水稻光谱特征和归一化植被指数(NDVI)等特点,对遥感影像进行分类处理并进行精度分析。结果表明,使用Landsat8_OLI遥感数据可以准确地提取曹妃甸区域的水稻种植面积,为大范围水稻种植及信息提取提供相应的数据参考。 展开更多
关键词 水稻 Landsat8_OLI 面积 遥感信息
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Isotope analysis of nitrate pollution sources in groundwater of Dong'e geohydrological unit 预览
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作者 LI Yang KANG Feng-Xin ZOU An-de 《地下水科学与工程:英文版》 2019年第2期145-154,共10页
As nitrate pollution in groundwater has become increasingly serious in recent years, nitrogen isotope was adopted in this paper to define its sources in a typical agricultural area of Dong5e hydrogeological unit. The ... As nitrate pollution in groundwater has become increasingly serious in recent years, nitrogen isotope was adopted in this paper to define its sources in a typical agricultural area of Dong5e hydrogeological unit. The results show that: Higher content of NO3^- detected in shallow groundwater is 27.77 mg/L on average and δ^15N content ranges from 7.8‰ to 12 ‰, indicating that shallow groundwater is mainly contaminated by sewage or feces. In contrast, less NO3^- in deep groundwater (karst water) has an average value of 12.81 mg/L and δ^15N content is between 7.2‰ and 14.3‰, which is closely related to human disturbance as mentioned above. In addition, considering relatively low groundwater quality at some monitoring sites, reasonable fertilization is a better choice in the study area to reduce nitrate source in groundwater. 展开更多
关键词 NITROGEN ISOTOPE GROUNDWATER NITROGEN POLLUTION source AGRICULTURAL area
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Examining the Relationship Between Spatial Configurations of Urban Impervious Surfaces and Land Surface Temperature 预览
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作者 WU Xiangli LI Binxia +3 位作者 LI Miao GUO Meixin ZANG Shuying ZHANG Shouzhi 《中国地理科学:英文版》 SCIE CSCD 2019年第4期568-578,共11页
The urban heat island(UHI) effect has significant effects on the quality of life and public health. Numerous studies have addressed the relationship between UHI and the increase in urban impervious surface area(ISA), ... The urban heat island(UHI) effect has significant effects on the quality of life and public health. Numerous studies have addressed the relationship between UHI and the increase in urban impervious surface area(ISA), but few of them have considered the impact of the spatial configuration of ISA on UHI. Land surface temperature(LST) may be affected not only by urban land cover, but also by neighboring land cover. The aim of this research was to investigate the effects of the abundance and spatial association of ISAs on LST. Taking Harbin City, China as an example, the impact of ISA spatial association on LST measurements was examined. The abundance of ISAs and the LST measurements were derived from Landsat Thematic Mapper(TM) imagery of 2000 and 2010, and the spatial association patterns of ISAs were calculated using the local Moran’s I index. The impacts of ISA abundance and spatial association on LST were examined using correlation analysis. The results suggested that LST has significant positive associations with both ISA abundance and the Moran’s I index of ISAs, indicating that both the abundance and spatial clustering of ISAs contribute to elevated values of LST. It was also found that LST is positively associated with clustering of high-ISA-percentage areas(i.e.,>50%) and negatively associated with clustering of low-ISA-percentage areas(i.e.,<25%). The results suggest that, in addition to the abundance of ISAs,their spatial association has a significant effect on UHIs. 展开更多
关键词 impervious surface area URBAN heat ISLAND LAND sruface temperature SPATIAL CONFIGURATION local Moran’s I index
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Use of Green Area of Kastamonu:Case Study of Clock Towe 预览
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作者 Çiğdem SAKICI 《环境社会心理学》 2019年第1期25-30,共6页
The aim of this study is to show which areas mainly preferred when the people want to carry out recreational activities in the Kastamonu city center and determine the appropriateness of this area for recreative activi... The aim of this study is to show which areas mainly preferred when the people want to carry out recreational activities in the Kastamonu city center and determine the appropriateness of this area for recreative activity.A questionnaire study was conducted with 100 randomly selected people in order to determine the most frequently used open green area in terms of recreational activity in Kastamonu and the results showed that 89%of the participants prefer the Clock Tower.Thus Clock Tower was determined as a research area in this study.It is revealed the current state of the Clock Tower in scope of the study:plants are used in this area and the purpose of use of these plants is determined and how frequently users use this area and the reasons for not frequent use.In addition,activities that are effected in the area and changes in mood after using the area.The second survey study was conducted on users of the area consisting of 118 people.It is revealed space features existing at Clock Tower and events area identified after that space features that users want to be in this area and events areas.Thus,the aim of the area is to determine the users'expectations and the deficiencies and problems in this area. 展开更多
关键词 Clock Tower RECREATION Use of Urban Green Area PREFERENCE ACTIVITY
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