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
[Objective] The aim was to reveal the effects of different land use types on soil composition. [Method] GPRS,soil organic carbon content and soil texture in 3 depths (0-10,10-20,20-50 cm) of 5 main kind of selected la...[Objective] The aim was to reveal the effects of different land use types on soil composition. [Method] GPRS,soil organic carbon content and soil texture in 3 depths (0-10,10-20,20-50 cm) of 5 main kind of selected land use type were examined in Hainan. [Result] The results showed that GRSP and SOC content of four artificial land use types decreased compared with the natural secondary forest land,the GRSP content of all samples ranged from 0.53-4.80 mg/g,accounting for 7.9%-23.4% of the SOC,which means that GRSP was one important component of SOC pool in soil. The ratio of GRSP to SOC was significantly different among land use types but the depths. GRSP and SOC exhibited obvious vertical distribution pattern. GRSP was significantly positively related to SOC and sand content but negatively related to silt and clay content. [Conclusion] The sand content determined the GRSP content significantly and loam was better matrix for GRSP accumulation than clay.展开更多
In recent Years, China's real estate market has been rapid developed, and real estate has become a hot spot of consumption and investment. In some large and medium-sized cities there has been a rapid rise in housing ...In recent Years, China's real estate market has been rapid developed, and real estate has become a hot spot of consumption and investment. In some large and medium-sized cities there has been a rapid rise in housing prices. The rapid rise in housing prices has led to difficulties in the purchase of houses in some cities and towns, and this phenomenon has aroused the attention and con- cern of all walks of life. Housing is the basic human life needs. Housing problem is not only an economic problem, but also a social problem. The relationship between house price and land price and the effective control of housing prices have become the focus of government and scholars. Thus, grey relational analysis is used to ana- lyze the relationship between housing prices and land prices, and the grey relational coefficients are calculated.展开更多
Weather and climate conditions drive the evolution of tropical glaciers which play an important role as water reservoirs for Peruvian inhabitants in the arid coast and semi-arid Andean region.The scarcity of long-term...Weather and climate conditions drive the evolution of tropical glaciers which play an important role as water reservoirs for Peruvian inhabitants in the arid coast and semi-arid Andean region.The scarcity of long-term high-quality observations over Peruvian glaciers has motivated the extensive use of reanalysis data to describe the climatic evolution of these glaciers.However,the representativeness and uncertainties of these reanalysis products over these glaciers are still poorly constrained.This study evaluates the ability of the ERA-Land reanalysis(ERAL)to reproduce hourly and monthly 2 m air temperature and relative humidity(T2m and Rh2m,respectively)over several Peruvian glaciers.We compared the ERAL with data from four on-glacier automatic weather stations(AWS),whose hourly time series were completed with nearby stations,for the period January 2017 to December 2019.Results indicates a better performance of the reanalysis for T2m(r>0.80)than for Rh2m(~0.4<r<~0.6)in all four glaciers.Concerning the observations,both parameters show a daily cycle influenced by the presence of the glacier.This influence is more prominent during the dry months when the so-called glacier damping and cooling effects are stronger.On a monthly time scale,the ERAL validation for both parameters are better in wet outer tropical sites(RMSE between±0.2℃ for T2m and between 3%-7% for Rh2m)rather than in dry outer tropical sites(RMSE between±0.2℃ for T2m and between 3%-7% for Rh2m).Among all sites considered in the study,the Rh2m bias is the highest in the Cavalca glacier(correlation of 0.81;RMSE 13%,MAE 11% and bias 8.3%)and the lowest in Artesonraju glacier(correlation of 0.96;RMSE 3%;MAE 2.3% and bias-0.8%).Based on certain considerations outlined in this paper,it is appropriate to use ERAL to characterize T2m and Rh2m conditions on Peruvian glaciers,particularly in the wet outer tropics.展开更多
Under the background of the new urbanization,this paper performs an empirical analysis of requisition-compensation balance indicators in Chuzhou City,and points out the problems in the land transaction.At the national...Under the background of the new urbanization,this paper performs an empirical analysis of requisition-compensation balance indicators in Chuzhou City,and points out the problems in the land transaction.At the national level,it is necessary to introduce the measures to regulate the market transactions of requisition-compensation balance indicators as soon as possible,put safeguarding the interests of the majority of farmers in the first place during market transactions,and establish the a unified market platform for the transaction of land-related indicators,so as to boost the urban construction,promote the integration of urban and rural areas,and speed up the new urbanization process.展开更多
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 National Natural Science Foundation of China(40761024)~~
文摘[Objective] The aim was to reveal the effects of different land use types on soil composition. [Method] GPRS,soil organic carbon content and soil texture in 3 depths (0-10,10-20,20-50 cm) of 5 main kind of selected land use type were examined in Hainan. [Result] The results showed that GRSP and SOC content of four artificial land use types decreased compared with the natural secondary forest land,the GRSP content of all samples ranged from 0.53-4.80 mg/g,accounting for 7.9%-23.4% of the SOC,which means that GRSP was one important component of SOC pool in soil. The ratio of GRSP to SOC was significantly different among land use types but the depths. GRSP and SOC exhibited obvious vertical distribution pattern. GRSP was significantly positively related to SOC and sand content but negatively related to silt and clay content. [Conclusion] The sand content determined the GRSP content significantly and loam was better matrix for GRSP accumulation than clay.
文摘In recent Years, China's real estate market has been rapid developed, and real estate has become a hot spot of consumption and investment. In some large and medium-sized cities there has been a rapid rise in housing prices. The rapid rise in housing prices has led to difficulties in the purchase of houses in some cities and towns, and this phenomenon has aroused the attention and con- cern of all walks of life. Housing is the basic human life needs. Housing problem is not only an economic problem, but also a social problem. The relationship between house price and land price and the effective control of housing prices have become the focus of government and scholars. Thus, grey relational analysis is used to ana- lyze the relationship between housing prices and land prices, and the grey relational coefficients are calculated.
基金funded by the Ministry of Science and Innovation of Spain through the research project(PID2020-113247RA-C22)by the National Fund for Scientific and Technological Development of Peru trough the PERMAFROST ENSO research project(081-2021)。
文摘Weather and climate conditions drive the evolution of tropical glaciers which play an important role as water reservoirs for Peruvian inhabitants in the arid coast and semi-arid Andean region.The scarcity of long-term high-quality observations over Peruvian glaciers has motivated the extensive use of reanalysis data to describe the climatic evolution of these glaciers.However,the representativeness and uncertainties of these reanalysis products over these glaciers are still poorly constrained.This study evaluates the ability of the ERA-Land reanalysis(ERAL)to reproduce hourly and monthly 2 m air temperature and relative humidity(T2m and Rh2m,respectively)over several Peruvian glaciers.We compared the ERAL with data from four on-glacier automatic weather stations(AWS),whose hourly time series were completed with nearby stations,for the period January 2017 to December 2019.Results indicates a better performance of the reanalysis for T2m(r>0.80)than for Rh2m(~0.4<r<~0.6)in all four glaciers.Concerning the observations,both parameters show a daily cycle influenced by the presence of the glacier.This influence is more prominent during the dry months when the so-called glacier damping and cooling effects are stronger.On a monthly time scale,the ERAL validation for both parameters are better in wet outer tropical sites(RMSE between±0.2℃ for T2m and between 3%-7% for Rh2m)rather than in dry outer tropical sites(RMSE between±0.2℃ for T2m and between 3%-7% for Rh2m).Among all sites considered in the study,the Rh2m bias is the highest in the Cavalca glacier(correlation of 0.81;RMSE 13%,MAE 11% and bias 8.3%)and the lowest in Artesonraju glacier(correlation of 0.96;RMSE 3%;MAE 2.3% and bias-0.8%).Based on certain considerations outlined in this paper,it is appropriate to use ERAL to characterize T2m and Rh2m conditions on Peruvian glaciers,particularly in the wet outer tropics.
基金Supported by Soft Science Project of Anhui Provincial Department of Land and Resources(2013001)
文摘Under the background of the new urbanization,this paper performs an empirical analysis of requisition-compensation balance indicators in Chuzhou City,and points out the problems in the land transaction.At the national level,it is necessary to introduce the measures to regulate the market transactions of requisition-compensation balance indicators as soon as possible,put safeguarding the interests of the majority of farmers in the first place during market transactions,and establish the a unified market platform for the transaction of land-related indicators,so as to boost the urban construction,promote the integration of urban and rural areas,and speed up the new urbanization process.