Background: Particle size distribution and hydraulic conductivity of coastal no-agricultural lands are not available. This study characterized the particle size distribution and hydraulic conductivity on coastal non-a...Background: Particle size distribution and hydraulic conductivity of coastal no-agricultural lands are not available. This study characterized the particle size distribution and hydraulic conductivity on coastal non-agricultural land along the coastal plain of Gaza. Materials and Methods: Six soil profiles were digged along the coastal plain in Gaza Strip and soil samples were collected from 0 - 150 cm depth. Four soil plots around each site were used to determine the hydraulic conductivity using Infiltrometer method. Four particle size groups were identified, group 1 (630 nm), group 2 (200 nm), group 3 (63 nm) and group 4 (20 nm). Results: Dominancy of particle size group 2 was noticed in all sites followed by group 3. Groups 1 and 4 were less dominant in all sites. Hydraulic conductivity ranged from lower value 0.27 in the control soil plot in Khan Younis (site 1) to the highest value 1.76 m/s in disturbed soil plot in Shakhejjlen (site 3) with regression coefficient (R2) range of 0.9725 - 0.997 indicating strong positive association. Conclusion: It can be concluded that the coastal non-agricultural land is sandy with various hydraulic conductivity values due to different particle size distribution. These data are useful to the scientific community around the world and will be helpful to speculate potential risk factors to life of ecosystem.展开更多
Abstract: his paper explored the relationships among nonagricultural population, employment and land in an integrated framework, taking account of rural-urban land conversion into Carlino-Mills's model on the region...Abstract: his paper explored the relationships among nonagricultural population, employment and land in an integrated framework, taking account of rural-urban land conversion into Carlino-Mills's model on the regional growth. Two-stage-leastsquares and ordinary-least-squares were employed. Recent data for district (grade) cities in China (from 1999 to 2005) were used. Our results showed that: first, urban population influenced non-agricultural employment, and vice versa, but the evidence that non-agricultural employment influenced urban population was stronger than the evidence that urban population influenced non-agricultural employment; second, urban population and non-agricultural employment both influenced ruralurban land conversion, but the evidence that urban population influenced rural urban land conversion was more stronger than the evidence that non-agricultural employment did. We also found that: first, the employment from the secondary industry influenced urban population in a positive way, and vice versa, but the employment from the tertiary industry influenced urban population in a negative way, and vice versa; second, the employment from the secondary industry influenced rural-urban land conversion in a positive way, but the employment from the tertiary industry influenced rural-urban land conversion in a negative way. We can conclude that the key of urbanization is to speed up the process of non-agricultural employment, especially the employment from the tertiary industry, which might promote non-agricultural population, employment and land harmoniously.展开更多
Farmland is the most basic element for farmers’survival and development,and has a social security function.The conversion of agricultural land to non-agricultural land has gradually become the primary factor in the r...Farmland is the most basic element for farmers’survival and development,and has a social security function.The conversion of agricultural land to non-agricultural land has gradually become the primary factor in the reduction of agricultural land in various regions of China,seriously endangering China’s food security.Under the background of the rural revitalization strategy,the emergence of the conversion of agricultural land to non-agricultural land and the inevitability of its development were analyzed from both the acceleration of urbanization and the increase in land demand by using the literature research method.The importance of curbing the conversion of agricultural land to non-agricultural land to achieve the grand goal of strong agriculture,beautiful rural areas,and rich farmers was clarified,and then countermeasures and suggestions to curb the conversion of agricultural land to non-agricultural land were put forward,which is of great significance to promoting the effective implementation of China’s rural revitalization strategy.展开更多
Relationship between Chinese rural non-agricultural employment and farmland use circulation has always been a hot research topic without final conclusions.This paper uses survey data of"China Health and Retiremen...Relationship between Chinese rural non-agricultural employment and farmland use circulation has always been a hot research topic without final conclusions.This paper uses survey data of"China Health and Retirement Longitudinal Study(CHARLS)"covering 1,549 households of 95 villages in Zhejiang and Gansu Province in 2008.According to the data analysis,Zhejiang Province has a higher ratio of rural households leasing out their farmland than Gansu Province has,while the latter has a higher ratio of rural residents going out for earning a living.In both provinces,non-agricultural employment and farmland use circulation show significant positive correlation,but in Gansu,non-agricultural employment of farmers shows no significant positive correlation with rural households leasing out their farmland.The factor shows that for peasants in underdeveloped regions of west China,they rely more on land because of its social security functions,so they are not willing to lease out their land even when they go to cities for earning a living.For local government,it is not appropriate to promote farmland use circulation by depending on the transfer of rural labor forces,fundamental needs of peasants must be taken into consideration.展开更多
The peri-urbanization area as a kind of rural-urban interface is changing rapidly ,physical, economlc and social terms. The land use pattern in such area is shifting away from the assumptions of mainstream paradigms t...The peri-urbanization area as a kind of rural-urban interface is changing rapidly ,physical, economlc and social terms. The land use pattern in such area is shifting away from the assumptions of mainstream paradigms to new conceptual landscapes, which leads to a series of problems on economic development and social stabilization. There are many researches on non-agricultural land-use in peri-urbanization area. In this paper both international and domestic research literature is reviewed by dividing six parts. The first part introduces the conception of peri-ur-banization area and its driver factors. Then in the second and the third part, the paper expatiates on the progress in the non-agricultural land-use in peri-urban area on land-use problems in the research area, while the fifth part reviews the integrating ways of non-agricultrual land-use. Finally, recommendations for further study are draw with specific reference to the current and future position of non-agricultural land-use study in peri-urban area.展开更多
Promoting women’s employment is not only the need of social and economic development,but also the historical mission of liberating women.This paper uses data from the 1%Population Sample Survey,taken in Guangdong Pro...Promoting women’s employment is not only the need of social and economic development,but also the historical mission of liberating women.This paper uses data from the 1%Population Sample Survey,taken in Guangdong Province in 2015,to explore how women’s marital status,education,and family environment affect the female non-agricultural employment rate(FNAER)on a county scale using a spatial-lag model.The results show that:1)The female non-agricultural employment rate in counties of Guangdong Province is low,with more than three-quarters of counties having female non-agricultural employment rate less than 50%.Moreover,the spatial distribution of FNAER is uneven,with the high-value areas concentrated in the southeast and the low-value areas mainly distributed in the central and western parts of Guangdong Province.2)From the perspective of industry,there are significant spatial differences among women.In the southeast,women are mainly engaged in the secondary industry,while in the central and western regions,women are mainly engaged in the tertiary industry.3)Women having better skills and more effective support from the elderly can improve the FNAER.Women having lower skills,smaller-scale families,a higher fertility rate,and households with two or more elderly members have a negative effect on the FNAER.4)Public policies suggest that improving women’s education and their family environment,building social welfare facilities,and repairing the family environment will increase the FNAER.展开更多
Income from non-agricultural industries operated by rural households is an important income source of farmers' income. According to the Regional Rural Residents' Net Income Per Capita in 2004 issued by the Sta...Income from non-agricultural industries operated by rural households is an important income source of farmers' income. According to the Regional Rural Residents' Net Income Per Capita in 2004 issued by the State Statistics Bureau and the relevant statistics of national comprehensive investigation(CGSS2005) in 2005, the impacts of farmers' income gap and farmers' individual features on their income and the impacts of income from non-agricultural industries operated by rural households on farmers' individual income differences are analyzed by applying Hierarchical Linear Models (HLM) as an analysis tool to establish the null model of HLM, excluding the second level model of the second level prediction variables and including the second level model of the second layer prediction variables. The analysis assumes that farmers' individual income varies hugely in different provinces; farmers' individual income has close relation with farmers' individual features; the improvement of income from non-agricultural industries operated by rural households has different impacts on farmers' income.展开更多
The continuous decrease of low-slope cropland resources caused by construction land crowding poses huge threat to regional sustainable development and food security.Slope spectrum analysis of topographic and geomorphi...The continuous decrease of low-slope cropland resources caused by construction land crowding poses huge threat to regional sustainable development and food security.Slope spectrum analysis of topographic and geomorphic features is considered as a digital terrain analysis method which reflects the macro-topographic features by using micro-topographic factors.However,pieces of studies have extended the concept of slope spectrum in the field of geoscience to construction land to explore its expansion law,while research on the slope trend of cropland from that perspective remains rare.To address the gap,in virtue of spatial analysis and geographically weighted regression(GWR)model,the cropland use change in the Yangtze River Basin(YRB)from 2000 to 2020 was analyzed and the driving factors were explored from the perspective of slope spectrum.Results showed that the slope spectrum curves of cropland area-frequency in the YRB showed a first upward then a downward trend.The change curve of the slope spectrum of cropland in each province(municipality)exhibited various distribution patterns.Quantitative analysis of morphological parameters of cropland slope spectrum revealed that the further down the YRB,the stronger the flattening characteristics,the more obvious the concentration.The province experienced the greatest downhill cropland climbing(CLC)was Shannxi,while province experienced the highest uphill CLC was Zhejiang.The most common cropland use change type in the YRB was horizontal expansion type.The factors affecting average cropland climbing index(ACCI)were quite stable in different periods,while population density(POP)changed from negative to positive during the study period.This research is of practical significance for the rational utilization of cropland at the watershed scale.展开更多
Urban shrinkage has emerged as a widespread phenomenon globally and has a significant impact on land,particularly in terms of land use and price.This study focuses on 2851 county-level cities in China in 2005–2018(ex...Urban shrinkage has emerged as a widespread phenomenon globally and has a significant impact on land,particularly in terms of land use and price.This study focuses on 2851 county-level cities in China in 2005–2018(excluding Hong Kong,Macao,Taiwan,and‘no data’areas in Qinhai-Tibet Plateau)as the fundamental units of analysis.By employing nighttime light(NTL)data to identify shrinking cities,the propensity score matching(PSM)model was used to quantitatively examine the impact of shrinking cities on land prices,and evaluate the magnitude of this influence.The findings demonstrate the following:1)there were 613 shrinking cities in China,with moderate shrinkage being the most prevalent and severe shrinkage being the least.2)Regional disparities are evident in the spatial distribution of shrinking cities,especially in areas with diverse terrain.3)The spatial pattern of land price exhibits a significant correlated to the economic and administrative levels.4)Shrinking cities significantly negatively impact on the overall land price(ATT=–0.1241,P<0.05).However,the extent of the effect varies significantly among different spatial regions.This study contributes novel insights into the investigation of land prices and shrinking cities,ultimately serving as a foundation for government efforts to promote the sustainable development of urban areas.展开更多
After landing in the Utopia Planitia,Tianwen-1 formed the deepest landing crater on Mars,approximately 40 cm deep,exposing precious information about the mechanical properties of Martian soil.We established numerical ...After landing in the Utopia Planitia,Tianwen-1 formed the deepest landing crater on Mars,approximately 40 cm deep,exposing precious information about the mechanical properties of Martian soil.We established numerical models for the plume-surface interaction(PSI)and the crater formation based on Computational Fluid Dynamics(CFD)methods and the erosion model modified from Roberts’Theory.Comparative studies of cases were conducted with different nozzle heights and soil mechanical properties.The increase in cohesion and internal friction angle leads to a decrease in erosion rate and maximum crater depth,with the cohesion having a greater impact.The influence of the nozzle height is not clear,as it interacts with the position of the Shock Diamond to jointly control the erosion process.Furthermore,we categorized the evolution of landing craters into the dispersive and the concentrated erosion modes based on the morphological characteristics.Finally,we estimated the upper limits of the Martian soil’s mechanical properties near Tianwen-1 landing site,with the cohesion ranging from 2612 to 2042 Pa and internal friction angle from 25°to 41°.展开更多
Aquifer thermal energy storage(ATES)system has received attention for heating or cooling buildings.However,it is well known that land subsidence becomes a major environmental concern for ATES projects.Yet,the effect o...Aquifer thermal energy storage(ATES)system has received attention for heating or cooling buildings.However,it is well known that land subsidence becomes a major environmental concern for ATES projects.Yet,the effect of temperature on land subsidence has received practically no attention in the past.This paper presents a thermo-hydro-mechanical(THM)coupled numerical study on an ATES system in Shanghai,China.Four water wells were installed for seasonal heating and cooling of an agriculture greenhouse.The target aquifer at a depth of 74e104.5 m consisted of alternating layers of sand and silty sand and was covered with clay.Groundwater level,temperature,and land subsidence data from 2015 to 2017 were collected using field monitoring instruments.Constrained by data,we constructed a field scale three-dimensional(3D)model using TOUGH(Transport of Unsaturated Groundwater and Heat)and FLAC3D(Fast Lagrangian Analysis of Continua)equipped with a thermo-elastoplastic constitutive model.The effectiveness of the numerical model was validated by field data.The model was used to reproduce groundwater flow,heat transfer,and mechanical responses in porous media over three years and capture the thermo-and pressure-induced land subsidence.The results show that the maximum thermoinduced land subsidence accounts for about 60%of the total subsidence.The thermo-induced subsidence is slightly greater in winter than that in summer,and more pronounced near the cold well area than the hot well area.This study provides some valuable guidelines for controlling land subsidence caused by ATES systems installed in soft soils.展开更多
Analysis of catchment Land use/Land cover (LULC) change is a vital tool in ensuring sustainable catchment management. The study analyzed land use/land cover changes in the Rwizi catchment, south western Uganda from 19...Analysis of catchment Land use/Land cover (LULC) change is a vital tool in ensuring sustainable catchment management. The study analyzed land use/land cover changes in the Rwizi catchment, south western Uganda from 1989-2019 and projected the trend by 2040. Landsat images, field observations, key informant interviews and focus group discussions were used to collect data. Changes in cropland, forestland, built up area, grazing land, wetland and open water bodies were analyzed in ArcGIS version 10.2.2 and ERDAS IMAGINE 14 software and a Markov chain model. All the LULC classes increased in area except grazing land. Forest land and builtup area between 2009-2019 increased by 370.03% and 229.53% respectively. Projections revealed an increase in forest land and builtup area by 2030 and only built up area by 2040. LULCC in the catchment results from population pressure, reduced soil fertility and high value of agricultural products.展开更多
Urban expansion of cities has caused changes in land use and land cover(LULC)in addition to transformations in the spatial characteristics of landscape structure.These alterations have generated heat islands and rise ...Urban expansion of cities has caused changes in land use and land cover(LULC)in addition to transformations in the spatial characteristics of landscape structure.These alterations have generated heat islands and rise of land surface temperature(LST),which consequently have caused a variety of environmental issues and threated the sustainable development of urban areas.Greenbelts are employed as an urban planning containment policy to regulate urban expansion,safeguard natural open spaces,and serve adaptation and mitigation functions.And they are regarded as a powerful measure for enhancing urban environmental sustainability.Despite the fact that,the relation between landscape structure change and variation of LST has been examined thoroughly in many studies,but there is a limitation concerning this relation in semi-arid climate and in greenbelts as well,with the lacking of comprehensive research combing both aspects.Accordingly,this study investigated the spatiotemporal changes of landscape pattern of LULC and their relationship with variation of LST within an inner greenbelt in the semi-arid Erbil City of northern Iraq.The study utilized remote sensing data to retrieve LST,classified LULC,and calculated landscape metrics for analyzing spatial changes during the study period.The results indicated that both composition and configuration of LULC had an impact on the variation of LST in the study area.The Pearson's correlation showed the significant effect of Vegetation 1 type(VH),cultivated land(CU),and bare soil(BS)on LST,as increase of LST was related to the decrease of VH and the increases of CU and BS,while,neither Vegetation 2 type(VL)nor built-up(BU)had any effects.Additionally,the spatial distribution of LULC also exhibited significant effects on LST,as LST was strongly correlated with landscape indices for VH,CU,and BS.However,for BU,only aggregation index metric affected LST,while none of VL metrics had a relation.The study provides insights for landscape planners and policymakers to not only develop more green spaces in greenbelt but also optimize the spatial landscape patterns to reduce the influence of LST on the urban environment,and further promote sustainable development and enhance well-being in the cities with semi-arid climate.展开更多
Coastal land transformation has been identified as a topic of research in many countries around the world.Several studies have been conducted to determine the causes and impacts of land transformation.However,much les...Coastal land transformation has been identified as a topic of research in many countries around the world.Several studies have been conducted to determine the causes and impacts of land transformation.However,much less is understood about coupling change detection,factors,impacts,and adaptation strategies for coastal land transformation at a global scale.This review aims to present a systematic review of global coastal land transformation and its leading research areas.From 1,741 documents of Scopus and Web of Science,60 studies have been selected using the PRISMA-2020 guideline.Results revealed that existing literature included four leading focus areas regarding coastal land transformation:change detection,driving factors,impacts,and adaptation measures.These focus areas were further analyzed,and it was found that more than 80%of studies used Landsat imagery to detect land transformation.Population growth and urbanization were among the major driving factors identified.This review further identified that about 37%of studies included impact analysis.These studies identified impacts on ecosystems,land surface temperature,migration,water quality,and occupational effects as significant impacts.However,only four studies included adaptation strategies.This review explored the scope of comprehensive research in coastal land transformation,addressing change detection,factor and impact analysis,and mitigation-adaptation strategies.The research also proposes a conceptual framework for comprehensive coastal land transformation analysis.The framework can provide potential decision-making guidance for future studies in coastal land transformation.展开更多
Under the influence of anthropogenic and climate change,the problems caused by urban heat island(UHI)has become increasingly prominent.In order to promote urban sustainable development and improve the quality of human...Under the influence of anthropogenic and climate change,the problems caused by urban heat island(UHI)has become increasingly prominent.In order to promote urban sustainable development and improve the quality of human settlements,it is significant for exploring the evolution characteristics of urban thermal environment and analyzing its driving forces.Taking the Landsat series images as the basic data sources,the winter land surface temperature(LST)of the rapid urbanization area of Fuzhou City in China was quantitatively retrieved from 2001 to 2021.Combing comprehensively the standard deviation ellipse model,profile analysis and GeoDetector model,the spatio-temporal evolution characteristics and influencing factors of the winter urban thermal environment were systematically analyzed.The results showed that the winter LST presented an increasing trend in the study area during 2001–2021,and the winter LST of the central urban regions was significantly higher than the suburbs.There was a strong UHI effect from 2001 to 2021with an expansion trend from the central urban regions to the suburbs and coastal areas in space scale.The LST of green lands and wetlands are significantly lower than croplands,artificial surface and unvegetated lands.Vegetation and water bodies had a significant mitigation effect on UHI,especially in the micro-scale.The winter UHI had been jointly driven by the underlying surface and socio-economic factors in a nonlinear or two-factor interactive enhancement mode,and socio-economic factors had played a leading role.This research could provide data support and decision-making references for rationally planning urban layout and promoting sustainable urban development.展开更多
利用全国40个地面台站的观测资料对ERA5及ERA5-Land两种不同空间分辨率的再分析资料开展了地面风速误差评估研究,结果表明:ERA5和ERA5-Land资料多年平均风速偏差的平均值分别为0.08 m s^(−1)、-0.06 m s^(−1),偏差的最大值分别为0.46 m ...利用全国40个地面台站的观测资料对ERA5及ERA5-Land两种不同空间分辨率的再分析资料开展了地面风速误差评估研究,结果表明:ERA5和ERA5-Land资料多年平均风速偏差的平均值分别为0.08 m s^(−1)、-0.06 m s^(−1),偏差的最大值分别为0.46 m s^(−1)、-0.19 m s^(−1),相对偏差的平均值为4.4%、-2.0%,相对偏差的最大值分别为33.0%、-10.1%;月平均风速线性拟合方程的斜率分别为0.93、0.97,截距分别为0.29 m s^(−1)、0.02 m s^(−1),相关系数分别为0.98、0.99;月平均风速均方根误差的平均值分别为0.17 m s^(−1)、0.14 m s^(−1),均方根误差的最大值分别为0.49 m s^(−1)、0.22 m s^(−1),相对均方根误差的平均值为7.4%、5.7%,相对均方根误差的最大值分别为35.2%、13.3%。ERA5-Land高分辨率资料地面风速误差相对较低,有利于提高风能资源评估的准确性。展开更多
Land use and cover change(LUCC)is important for the provision of ecosystem services.An increasing number of recent studies link LUCC processes to ecosystem services and human well-being at different scales recently.Ho...Land use and cover change(LUCC)is important for the provision of ecosystem services.An increasing number of recent studies link LUCC processes to ecosystem services and human well-being at different scales recently.However,the dynamic of land use and its drivers receive insufficient attention within ecological function areas,particularly in quantifying the dynamic roles of climate change and human activities on land use based on a long time series.This study utilizes geospatial analysis and geographical detectors to examine the temporal dynamics of land use patterns and their underlying drivers in the Hedong Region of the Gansu Province from 1990 to 2020.Results indicated that grassland,cropland,and forestland collectively accounted for approximately 99% of the total land area.Cropland initially increased and then decreased after 2000,while grassland decreased with fluctuations.In contrast,forestland and construction land were continuously expanded,with net growth areas of 6235.2 and 455.9 km^(2),respectively.From 1990 to 2020,cropland was converted to grassland,and both of them were converted to forestland as a whole.The expansion of construction land primarily originated from cropland.From 2000 to 2005,land use experienced intensified temporal dynamics and a shift of relatively active zones from the central to the southeastern region.Grain yield,economic factors,and precipitation were the major factors accounting for most land use changes.Climatic impacts on land use changes were stronger before 1995,succeeded by the impact of animal husbandry during 1995-2000,followed by the impacts of grain production and gross domestic product(GDP)after 2000.Moreover,agricultural and pastoral activities,coupled with climate change,exhibited stronger enhancement effects after 2000 through their interaction with population and economic factors.These patterns closely correlated with ecological restoration projects in China since 1999.This study implies the importance of synergy between human activity and climate change for optimizing land use via ecological patterns in the ecological function area.展开更多
Land cover is an impression of natural cover on surface of earth such as bare soil, river, grass etc. and utilization of these natural covers for various human needs and purposes by mankind is defined as land use. Lan...Land cover is an impression of natural cover on surface of earth such as bare soil, river, grass etc. and utilization of these natural covers for various human needs and purposes by mankind is defined as land use. Land cover identification, delineation and mapping is important for planning activities, resource management and global monitoring studies while baseline mapping and subsequent monitoring is done by application of land use to get timely information about quantity of land that has been used. The present study has been carried out in Dhund river watershed of Jaipur, Rajasthan which covers an area of about 1828 sq∙km. The minimum and maximum elevation of the area is found to be 214 m and 603 m respectively. Land use and land cover changes of three decades from 1991 to 2021 have been interpreted by using remotes sensing and GIS techniques. ArcGIS software (Arc map 10.2), SOI topographic map, Cartosat-1 DEM and satellite data of Landsat 5 and Landsat 8 have been used for interpretation of eleven classes. The study shows an increase in cultivated land, settlement, waterbody, open forest, plantation and mining due to urbanization because of increasing demands of food, shelter and water while a decrease in dense forest, river, open scrub, wasteland and uncultivated land has also been marked due to destruction of aforementioned by anthropogenic activities such as industrialization resulting in environmental degradation that leads to air, soil and water pollution.展开更多
Terrestrial carbon storage(CS)plays a crucial role in achieving carbon balance and mitigating global climate change.This study employs the Shared Socioeconomic Pathways and Representative Concentration Pathways(SSPs-R...Terrestrial carbon storage(CS)plays a crucial role in achieving carbon balance and mitigating global climate change.This study employs the Shared Socioeconomic Pathways and Representative Concentration Pathways(SSPs-RCPs)published by the Intergovernmental Panel on Climate Change(IPCC)and incorporates the Policy Control Scenario(PCS)regulated by China’s land management policies.The Future Land Use Simulation(FLUS)model is employed to generate a 1 km resolution land use/cover change(LUCC)dataset for China in 2030 and 2060.Based on the carbon density dataset of China’s terrestrial ecosystems,the study analyses CS changes and their relationship with land use changes spanning from 1990 to 2060.The findings indicate that the quantitative changes in land use in China from 1990 to 2020 are characterised by a reduction in the area proportion of cropland and grassland,along with an increase in the impervious surface and forest area.This changing trend is projected to continue under the PCS from 2020 to 2060.Under the SSPs-RCPs scenario,the proportion of cropland and impervious surface predominantly increases,while the proportions of forest and grassland continuously decrease.Carbon loss in China’s carbon storage from 1990 to 2020 amounted to 0.53×10^(12)kg,primarily due to the reduced area of cropland and grassland.In the SSPs-RCPs scenario,more significant carbon loss occurs,reaching a peak of8.07×10^(12)kg in the SSP4-RCP3.4 scenario.Carbon loss is mainly concentrated in the southeastern coastal area and the Beijing-TianjinHebei(BTH)region of China,with urbanisation and deforestation identified as the primary drivers.In the future,it is advisable to enhance the protection of forests and grassland while stabilising cropland areas and improving the intensity of urban land.These research findings offer valuable data support for China’s land management policy,land space optimisation,and the achievement of dual-carbon targets.展开更多
文摘Background: Particle size distribution and hydraulic conductivity of coastal no-agricultural lands are not available. This study characterized the particle size distribution and hydraulic conductivity on coastal non-agricultural land along the coastal plain of Gaza. Materials and Methods: Six soil profiles were digged along the coastal plain in Gaza Strip and soil samples were collected from 0 - 150 cm depth. Four soil plots around each site were used to determine the hydraulic conductivity using Infiltrometer method. Four particle size groups were identified, group 1 (630 nm), group 2 (200 nm), group 3 (63 nm) and group 4 (20 nm). Results: Dominancy of particle size group 2 was noticed in all sites followed by group 3. Groups 1 and 4 were less dominant in all sites. Hydraulic conductivity ranged from lower value 0.27 in the control soil plot in Khan Younis (site 1) to the highest value 1.76 m/s in disturbed soil plot in Shakhejjlen (site 3) with regression coefficient (R2) range of 0.9725 - 0.997 indicating strong positive association. Conclusion: It can be concluded that the coastal non-agricultural land is sandy with various hydraulic conductivity values due to different particle size distribution. These data are useful to the scientific community around the world and will be helpful to speculate potential risk factors to life of ecosystem.
基金co-supported by National Natural Science Foundation of China(grant no.70773047)Doctoral Foundation of the Ministry of Edncation(grant no.20070504020)
文摘Abstract: his paper explored the relationships among nonagricultural population, employment and land in an integrated framework, taking account of rural-urban land conversion into Carlino-Mills's model on the regional growth. Two-stage-leastsquares and ordinary-least-squares were employed. Recent data for district (grade) cities in China (from 1999 to 2005) were used. Our results showed that: first, urban population influenced non-agricultural employment, and vice versa, but the evidence that non-agricultural employment influenced urban population was stronger than the evidence that urban population influenced non-agricultural employment; second, urban population and non-agricultural employment both influenced ruralurban land conversion, but the evidence that urban population influenced rural urban land conversion was more stronger than the evidence that non-agricultural employment did. We also found that: first, the employment from the secondary industry influenced urban population in a positive way, and vice versa, but the employment from the tertiary industry influenced urban population in a negative way, and vice versa; second, the employment from the secondary industry influenced rural-urban land conversion in a positive way, but the employment from the tertiary industry influenced rural-urban land conversion in a negative way. We can conclude that the key of urbanization is to speed up the process of non-agricultural employment, especially the employment from the tertiary industry, which might promote non-agricultural population, employment and land harmoniously.
文摘Farmland is the most basic element for farmers’survival and development,and has a social security function.The conversion of agricultural land to non-agricultural land has gradually become the primary factor in the reduction of agricultural land in various regions of China,seriously endangering China’s food security.Under the background of the rural revitalization strategy,the emergence of the conversion of agricultural land to non-agricultural land and the inevitability of its development were analyzed from both the acceleration of urbanization and the increase in land demand by using the literature research method.The importance of curbing the conversion of agricultural land to non-agricultural land to achieve the grand goal of strong agriculture,beautiful rural areas,and rich farmers was clarified,and then countermeasures and suggestions to curb the conversion of agricultural land to non-agricultural land were put forward,which is of great significance to promoting the effective implementation of China’s rural revitalization strategy.
基金Sponsored by Key Projects of Chongqing Humanities and Social Science Key Research Center(Agricultural Education Development Research Center of Southwest University)(10SKB03,11SKB32)Youth Program of National Social Science Foundation(12CGL063)+2 种基金Youth Program of Humanities and Social Science Foundation of the Ministry of Education(13YJC790101)Basic Scientific Research Program of Central Universities(SWU1309392)Youth Program of Chongqing Social Science Planning(2012QNJJ011)
文摘Relationship between Chinese rural non-agricultural employment and farmland use circulation has always been a hot research topic without final conclusions.This paper uses survey data of"China Health and Retirement Longitudinal Study(CHARLS)"covering 1,549 households of 95 villages in Zhejiang and Gansu Province in 2008.According to the data analysis,Zhejiang Province has a higher ratio of rural households leasing out their farmland than Gansu Province has,while the latter has a higher ratio of rural residents going out for earning a living.In both provinces,non-agricultural employment and farmland use circulation show significant positive correlation,but in Gansu,non-agricultural employment of farmers shows no significant positive correlation with rural households leasing out their farmland.The factor shows that for peasants in underdeveloped regions of west China,they rely more on land because of its social security functions,so they are not willing to lease out their land even when they go to cities for earning a living.For local government,it is not appropriate to promote farmland use circulation by depending on the transfer of rural labor forces,fundamental needs of peasants must be taken into consideration.
文摘The peri-urbanization area as a kind of rural-urban interface is changing rapidly ,physical, economlc and social terms. The land use pattern in such area is shifting away from the assumptions of mainstream paradigms to new conceptual landscapes, which leads to a series of problems on economic development and social stabilization. There are many researches on non-agricultural land-use in peri-urbanization area. In this paper both international and domestic research literature is reviewed by dividing six parts. The first part introduces the conception of peri-ur-banization area and its driver factors. Then in the second and the third part, the paper expatiates on the progress in the non-agricultural land-use in peri-urban area on land-use problems in the research area, while the fifth part reviews the integrating ways of non-agricultrual land-use. Finally, recommendations for further study are draw with specific reference to the current and future position of non-agricultural land-use study in peri-urban area.
基金Under the auspices of National Natural Science Foundation of China(No.41471111)。
文摘Promoting women’s employment is not only the need of social and economic development,but also the historical mission of liberating women.This paper uses data from the 1%Population Sample Survey,taken in Guangdong Province in 2015,to explore how women’s marital status,education,and family environment affect the female non-agricultural employment rate(FNAER)on a county scale using a spatial-lag model.The results show that:1)The female non-agricultural employment rate in counties of Guangdong Province is low,with more than three-quarters of counties having female non-agricultural employment rate less than 50%.Moreover,the spatial distribution of FNAER is uneven,with the high-value areas concentrated in the southeast and the low-value areas mainly distributed in the central and western parts of Guangdong Province.2)From the perspective of industry,there are significant spatial differences among women.In the southeast,women are mainly engaged in the secondary industry,while in the central and western regions,women are mainly engaged in the tertiary industry.3)Women having better skills and more effective support from the elderly can improve the FNAER.Women having lower skills,smaller-scale families,a higher fertility rate,and households with two or more elderly members have a negative effect on the FNAER.4)Public policies suggest that improving women’s education and their family environment,building social welfare facilities,and repairing the family environment will increase the FNAER.
文摘Income from non-agricultural industries operated by rural households is an important income source of farmers' income. According to the Regional Rural Residents' Net Income Per Capita in 2004 issued by the State Statistics Bureau and the relevant statistics of national comprehensive investigation(CGSS2005) in 2005, the impacts of farmers' income gap and farmers' individual features on their income and the impacts of income from non-agricultural industries operated by rural households on farmers' individual income differences are analyzed by applying Hierarchical Linear Models (HLM) as an analysis tool to establish the null model of HLM, excluding the second level model of the second level prediction variables and including the second level model of the second layer prediction variables. The analysis assumes that farmers' individual income varies hugely in different provinces; farmers' individual income has close relation with farmers' individual features; the improvement of income from non-agricultural industries operated by rural households has different impacts on farmers' income.
基金supported in part by the Key Laboratory of Natural Resources Monitoring and Supervision in Southern Hilly Region,Ministry of Natural Resources(NRMSSHR2023Y02)Yunnan Key Laboratory of Plateau Geographic Processes and Environmental Changes(PGPEC2304)+1 种基金Yunnan Normal University,China.This study was also sponsored by the Scientific Research Project of Education Department of Hubei Province(Grant No.B2022262)the Philosophy and Social Sciences Research Project of Education Department of Hubei Province(Grant No.22G024).
文摘The continuous decrease of low-slope cropland resources caused by construction land crowding poses huge threat to regional sustainable development and food security.Slope spectrum analysis of topographic and geomorphic features is considered as a digital terrain analysis method which reflects the macro-topographic features by using micro-topographic factors.However,pieces of studies have extended the concept of slope spectrum in the field of geoscience to construction land to explore its expansion law,while research on the slope trend of cropland from that perspective remains rare.To address the gap,in virtue of spatial analysis and geographically weighted regression(GWR)model,the cropland use change in the Yangtze River Basin(YRB)from 2000 to 2020 was analyzed and the driving factors were explored from the perspective of slope spectrum.Results showed that the slope spectrum curves of cropland area-frequency in the YRB showed a first upward then a downward trend.The change curve of the slope spectrum of cropland in each province(municipality)exhibited various distribution patterns.Quantitative analysis of morphological parameters of cropland slope spectrum revealed that the further down the YRB,the stronger the flattening characteristics,the more obvious the concentration.The province experienced the greatest downhill cropland climbing(CLC)was Shannxi,while province experienced the highest uphill CLC was Zhejiang.The most common cropland use change type in the YRB was horizontal expansion type.The factors affecting average cropland climbing index(ACCI)were quite stable in different periods,while population density(POP)changed from negative to positive during the study period.This research is of practical significance for the rational utilization of cropland at the watershed scale.
基金Under the auspices of National Natural Science Foundation of China(No.42071222,41771194)。
文摘Urban shrinkage has emerged as a widespread phenomenon globally and has a significant impact on land,particularly in terms of land use and price.This study focuses on 2851 county-level cities in China in 2005–2018(excluding Hong Kong,Macao,Taiwan,and‘no data’areas in Qinhai-Tibet Plateau)as the fundamental units of analysis.By employing nighttime light(NTL)data to identify shrinking cities,the propensity score matching(PSM)model was used to quantitatively examine the impact of shrinking cities on land prices,and evaluate the magnitude of this influence.The findings demonstrate the following:1)there were 613 shrinking cities in China,with moderate shrinkage being the most prevalent and severe shrinkage being the least.2)Regional disparities are evident in the spatial distribution of shrinking cities,especially in areas with diverse terrain.3)The spatial pattern of land price exhibits a significant correlated to the economic and administrative levels.4)Shrinking cities significantly negatively impact on the overall land price(ATT=–0.1241,P<0.05).However,the extent of the effect varies significantly among different spatial regions.This study contributes novel insights into the investigation of land prices and shrinking cities,ultimately serving as a foundation for government efforts to promote the sustainable development of urban areas.
基金supported by the Key Research Program of the Institute of Geology and Geophysics,CAS(Nos.IGGCAS-202102 and IGGCAS-201904)the National Natural Science Foundation of China(No.42230111)the CAS Key Technology Talent Program。
文摘After landing in the Utopia Planitia,Tianwen-1 formed the deepest landing crater on Mars,approximately 40 cm deep,exposing precious information about the mechanical properties of Martian soil.We established numerical models for the plume-surface interaction(PSI)and the crater formation based on Computational Fluid Dynamics(CFD)methods and the erosion model modified from Roberts’Theory.Comparative studies of cases were conducted with different nozzle heights and soil mechanical properties.The increase in cohesion and internal friction angle leads to a decrease in erosion rate and maximum crater depth,with the cohesion having a greater impact.The influence of the nozzle height is not clear,as it interacts with the position of the Shock Diamond to jointly control the erosion process.Furthermore,we categorized the evolution of landing craters into the dispersive and the concentrated erosion modes based on the morphological characteristics.Finally,we estimated the upper limits of the Martian soil’s mechanical properties near Tianwen-1 landing site,with the cohesion ranging from 2612 to 2042 Pa and internal friction angle from 25°to 41°.
基金sponsored by the National Key Research and Development Program of China(Grant No.2020YFC1808102).
文摘Aquifer thermal energy storage(ATES)system has received attention for heating or cooling buildings.However,it is well known that land subsidence becomes a major environmental concern for ATES projects.Yet,the effect of temperature on land subsidence has received practically no attention in the past.This paper presents a thermo-hydro-mechanical(THM)coupled numerical study on an ATES system in Shanghai,China.Four water wells were installed for seasonal heating and cooling of an agriculture greenhouse.The target aquifer at a depth of 74e104.5 m consisted of alternating layers of sand and silty sand and was covered with clay.Groundwater level,temperature,and land subsidence data from 2015 to 2017 were collected using field monitoring instruments.Constrained by data,we constructed a field scale three-dimensional(3D)model using TOUGH(Transport of Unsaturated Groundwater and Heat)and FLAC3D(Fast Lagrangian Analysis of Continua)equipped with a thermo-elastoplastic constitutive model.The effectiveness of the numerical model was validated by field data.The model was used to reproduce groundwater flow,heat transfer,and mechanical responses in porous media over three years and capture the thermo-and pressure-induced land subsidence.The results show that the maximum thermoinduced land subsidence accounts for about 60%of the total subsidence.The thermo-induced subsidence is slightly greater in winter than that in summer,and more pronounced near the cold well area than the hot well area.This study provides some valuable guidelines for controlling land subsidence caused by ATES systems installed in soft soils.
文摘Analysis of catchment Land use/Land cover (LULC) change is a vital tool in ensuring sustainable catchment management. The study analyzed land use/land cover changes in the Rwizi catchment, south western Uganda from 1989-2019 and projected the trend by 2040. Landsat images, field observations, key informant interviews and focus group discussions were used to collect data. Changes in cropland, forestland, built up area, grazing land, wetland and open water bodies were analyzed in ArcGIS version 10.2.2 and ERDAS IMAGINE 14 software and a Markov chain model. All the LULC classes increased in area except grazing land. Forest land and builtup area between 2009-2019 increased by 370.03% and 229.53% respectively. Projections revealed an increase in forest land and builtup area by 2030 and only built up area by 2040. LULCC in the catchment results from population pressure, reduced soil fertility and high value of agricultural products.
文摘Urban expansion of cities has caused changes in land use and land cover(LULC)in addition to transformations in the spatial characteristics of landscape structure.These alterations have generated heat islands and rise of land surface temperature(LST),which consequently have caused a variety of environmental issues and threated the sustainable development of urban areas.Greenbelts are employed as an urban planning containment policy to regulate urban expansion,safeguard natural open spaces,and serve adaptation and mitigation functions.And they are regarded as a powerful measure for enhancing urban environmental sustainability.Despite the fact that,the relation between landscape structure change and variation of LST has been examined thoroughly in many studies,but there is a limitation concerning this relation in semi-arid climate and in greenbelts as well,with the lacking of comprehensive research combing both aspects.Accordingly,this study investigated the spatiotemporal changes of landscape pattern of LULC and their relationship with variation of LST within an inner greenbelt in the semi-arid Erbil City of northern Iraq.The study utilized remote sensing data to retrieve LST,classified LULC,and calculated landscape metrics for analyzing spatial changes during the study period.The results indicated that both composition and configuration of LULC had an impact on the variation of LST in the study area.The Pearson's correlation showed the significant effect of Vegetation 1 type(VH),cultivated land(CU),and bare soil(BS)on LST,as increase of LST was related to the decrease of VH and the increases of CU and BS,while,neither Vegetation 2 type(VL)nor built-up(BU)had any effects.Additionally,the spatial distribution of LULC also exhibited significant effects on LST,as LST was strongly correlated with landscape indices for VH,CU,and BS.However,for BU,only aggregation index metric affected LST,while none of VL metrics had a relation.The study provides insights for landscape planners and policymakers to not only develop more green spaces in greenbelt but also optimize the spatial landscape patterns to reduce the influence of LST on the urban environment,and further promote sustainable development and enhance well-being in the cities with semi-arid climate.
文摘Coastal land transformation has been identified as a topic of research in many countries around the world.Several studies have been conducted to determine the causes and impacts of land transformation.However,much less is understood about coupling change detection,factors,impacts,and adaptation strategies for coastal land transformation at a global scale.This review aims to present a systematic review of global coastal land transformation and its leading research areas.From 1,741 documents of Scopus and Web of Science,60 studies have been selected using the PRISMA-2020 guideline.Results revealed that existing literature included four leading focus areas regarding coastal land transformation:change detection,driving factors,impacts,and adaptation measures.These focus areas were further analyzed,and it was found that more than 80%of studies used Landsat imagery to detect land transformation.Population growth and urbanization were among the major driving factors identified.This review further identified that about 37%of studies included impact analysis.These studies identified impacts on ecosystems,land surface temperature,migration,water quality,and occupational effects as significant impacts.However,only four studies included adaptation strategies.This review explored the scope of comprehensive research in coastal land transformation,addressing change detection,factor and impact analysis,and mitigation-adaptation strategies.The research also proposes a conceptual framework for comprehensive coastal land transformation analysis.The framework can provide potential decision-making guidance for future studies in coastal land transformation.
基金Under the auspices of the Social Science and Humanity on Young Fund of the Ministry of Education of China(No.21YJCZH100)the Scientific Research Project on Outstanding Young of the Fujian Agriculture and Forestry University(No.XJQ201920)+1 种基金the Science and Technology Innovation Special Fund Project of Fujian Agriculture and Forestry University(No.CXZX2021032)the Forestry Peak Discipline Construction Project of Fujian Agriculture and Forestry University(No.72202200205)。
文摘Under the influence of anthropogenic and climate change,the problems caused by urban heat island(UHI)has become increasingly prominent.In order to promote urban sustainable development and improve the quality of human settlements,it is significant for exploring the evolution characteristics of urban thermal environment and analyzing its driving forces.Taking the Landsat series images as the basic data sources,the winter land surface temperature(LST)of the rapid urbanization area of Fuzhou City in China was quantitatively retrieved from 2001 to 2021.Combing comprehensively the standard deviation ellipse model,profile analysis and GeoDetector model,the spatio-temporal evolution characteristics and influencing factors of the winter urban thermal environment were systematically analyzed.The results showed that the winter LST presented an increasing trend in the study area during 2001–2021,and the winter LST of the central urban regions was significantly higher than the suburbs.There was a strong UHI effect from 2001 to 2021with an expansion trend from the central urban regions to the suburbs and coastal areas in space scale.The LST of green lands and wetlands are significantly lower than croplands,artificial surface and unvegetated lands.Vegetation and water bodies had a significant mitigation effect on UHI,especially in the micro-scale.The winter UHI had been jointly driven by the underlying surface and socio-economic factors in a nonlinear or two-factor interactive enhancement mode,and socio-economic factors had played a leading role.This research could provide data support and decision-making references for rationally planning urban layout and promoting sustainable urban development.
文摘利用全国40个地面台站的观测资料对ERA5及ERA5-Land两种不同空间分辨率的再分析资料开展了地面风速误差评估研究,结果表明:ERA5和ERA5-Land资料多年平均风速偏差的平均值分别为0.08 m s^(−1)、-0.06 m s^(−1),偏差的最大值分别为0.46 m s^(−1)、-0.19 m s^(−1),相对偏差的平均值为4.4%、-2.0%,相对偏差的最大值分别为33.0%、-10.1%;月平均风速线性拟合方程的斜率分别为0.93、0.97,截距分别为0.29 m s^(−1)、0.02 m s^(−1),相关系数分别为0.98、0.99;月平均风速均方根误差的平均值分别为0.17 m s^(−1)、0.14 m s^(−1),均方根误差的最大值分别为0.49 m s^(−1)、0.22 m s^(−1),相对均方根误差的平均值为7.4%、5.7%,相对均方根误差的最大值分别为35.2%、13.3%。ERA5-Land高分辨率资料地面风速误差相对较低,有利于提高风能资源评估的准确性。
基金funded by the National Natural Science Foundation of China(U20A2098,41701219)the National Key Research and Development Program of China(2019YFC0507801)。
文摘Land use and cover change(LUCC)is important for the provision of ecosystem services.An increasing number of recent studies link LUCC processes to ecosystem services and human well-being at different scales recently.However,the dynamic of land use and its drivers receive insufficient attention within ecological function areas,particularly in quantifying the dynamic roles of climate change and human activities on land use based on a long time series.This study utilizes geospatial analysis and geographical detectors to examine the temporal dynamics of land use patterns and their underlying drivers in the Hedong Region of the Gansu Province from 1990 to 2020.Results indicated that grassland,cropland,and forestland collectively accounted for approximately 99% of the total land area.Cropland initially increased and then decreased after 2000,while grassland decreased with fluctuations.In contrast,forestland and construction land were continuously expanded,with net growth areas of 6235.2 and 455.9 km^(2),respectively.From 1990 to 2020,cropland was converted to grassland,and both of them were converted to forestland as a whole.The expansion of construction land primarily originated from cropland.From 2000 to 2005,land use experienced intensified temporal dynamics and a shift of relatively active zones from the central to the southeastern region.Grain yield,economic factors,and precipitation were the major factors accounting for most land use changes.Climatic impacts on land use changes were stronger before 1995,succeeded by the impact of animal husbandry during 1995-2000,followed by the impacts of grain production and gross domestic product(GDP)after 2000.Moreover,agricultural and pastoral activities,coupled with climate change,exhibited stronger enhancement effects after 2000 through their interaction with population and economic factors.These patterns closely correlated with ecological restoration projects in China since 1999.This study implies the importance of synergy between human activity and climate change for optimizing land use via ecological patterns in the ecological function area.
文摘Land cover is an impression of natural cover on surface of earth such as bare soil, river, grass etc. and utilization of these natural covers for various human needs and purposes by mankind is defined as land use. Land cover identification, delineation and mapping is important for planning activities, resource management and global monitoring studies while baseline mapping and subsequent monitoring is done by application of land use to get timely information about quantity of land that has been used. The present study has been carried out in Dhund river watershed of Jaipur, Rajasthan which covers an area of about 1828 sq∙km. The minimum and maximum elevation of the area is found to be 214 m and 603 m respectively. Land use and land cover changes of three decades from 1991 to 2021 have been interpreted by using remotes sensing and GIS techniques. ArcGIS software (Arc map 10.2), SOI topographic map, Cartosat-1 DEM and satellite data of Landsat 5 and Landsat 8 have been used for interpretation of eleven classes. The study shows an increase in cultivated land, settlement, waterbody, open forest, plantation and mining due to urbanization because of increasing demands of food, shelter and water while a decrease in dense forest, river, open scrub, wasteland and uncultivated land has also been marked due to destruction of aforementioned by anthropogenic activities such as industrialization resulting in environmental degradation that leads to air, soil and water pollution.
基金Under the auspices of the National Natural Science Foundation of China(No.41971219,41571168)Natural Science Foundation of Hunan Province(No.2020JJ4372)Philosophy and Social Science Fund Project of Hunan Province(No.18ZDB015)。
文摘Terrestrial carbon storage(CS)plays a crucial role in achieving carbon balance and mitigating global climate change.This study employs the Shared Socioeconomic Pathways and Representative Concentration Pathways(SSPs-RCPs)published by the Intergovernmental Panel on Climate Change(IPCC)and incorporates the Policy Control Scenario(PCS)regulated by China’s land management policies.The Future Land Use Simulation(FLUS)model is employed to generate a 1 km resolution land use/cover change(LUCC)dataset for China in 2030 and 2060.Based on the carbon density dataset of China’s terrestrial ecosystems,the study analyses CS changes and their relationship with land use changes spanning from 1990 to 2060.The findings indicate that the quantitative changes in land use in China from 1990 to 2020 are characterised by a reduction in the area proportion of cropland and grassland,along with an increase in the impervious surface and forest area.This changing trend is projected to continue under the PCS from 2020 to 2060.Under the SSPs-RCPs scenario,the proportion of cropland and impervious surface predominantly increases,while the proportions of forest and grassland continuously decrease.Carbon loss in China’s carbon storage from 1990 to 2020 amounted to 0.53×10^(12)kg,primarily due to the reduced area of cropland and grassland.In the SSPs-RCPs scenario,more significant carbon loss occurs,reaching a peak of8.07×10^(12)kg in the SSP4-RCP3.4 scenario.Carbon loss is mainly concentrated in the southeastern coastal area and the Beijing-TianjinHebei(BTH)region of China,with urbanisation and deforestation identified as the primary drivers.In the future,it is advisable to enhance the protection of forests and grassland while stabilising cropland areas and improving the intensity of urban land.These research findings offer valuable data support for China’s land management policy,land space optimisation,and the achievement of dual-carbon targets.