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Exploring complex urban growth and land use efficiency in China's developed regions:implications for territorial spatial planning

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Frontiers of Earth Science 2022年第4期16卷 1040-1051页

作者： Xiaolu TANG Li SHENG Yinkang ZHOU School of Geography and Ocean Science Nanjing UniversityNanjing 210023China Institute of Digital Agriculture Zhejiang Academy of Agricultural SciencesHangzhou 310021China

Developed regions in China have experienced rapid urban expansion and have consequently induced a series of challenging environmental issues since its economic reform and opening-up.Taking Zhejiang as a case study area,the present paper explores the complex types of urban growth over the last four decades as well as land use efficiency.Moreover,it discusses the implications of the aforementioned on China national territorial spatial planning(TSP).The acquired results have shown that:1)urban expansion has slowed down,exhibiting a three-stage trend of"slight increase(1980-1990)—dramatic growth(1990-2010)—slow growth(after 2010)";2)the complex types of urban growth reveal that the urban diffusion has been gradually controlled and the urban form tends to be more condensed;and 3)the mean values for pure technical efficiency(PTE)and scale efficiency(SE)of urban land use are 0.83 and 0.95 respectively,indicating PTE as the main factor restricting the improvement of urban land use.Based on these results,some beneficial policy implications and suggestions for TSP are provided.First,it is suggested that"Inventory Planning"will be the main direction of TSP other than"Incremental Planning".Secondly,we should pay more attention to the protection of cultivated land and ecological resources.Lastly,TSP should guide the economic growth away from simply relying on resource inputs and steer it toward technology and capital investment.

关键词： urban expansion urban growth types land use efficiency Zhejiang territorial spatial planning

Spatial-temporal change in urban agricultural land use efficiency from the perspective of agricultural multi-functionality： A case study of the Xi＇an metropolitan zone

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Journal of Geographical Sciences 2017年第12期27卷 1499-1520页

作者： ZHOU Zhongxue LI Mengtao College of Tourism and Environment Shaanxi Normal University Xi'an 710119 China

The excessive expansion of urbanized areas has resulted in haphazard land utili- zation, immoderate consumption of superior agricultural land and water resources, significant fragmentation of agricultural landscape, and gradual deterioration of the agro-ecological en- vironment. Combined, these factors cause poor land use efficiency. Under these circum- stances, comprehensively assessing land use efficiency for urban agriculture is a key issue in land use research. Currently, evaluation methods for agricultural land use efficiency narrowly concentrate on aspects of economic input and output. However, urban agro-ecosystems can provide diverse economic, social, and ecological services and functions. In particular, the social and ecological services and functions originating from agricultural land, which have a higher value than economic services, play a significant role in ensuring regional social, eco- logical, and environmental security. However, recent research has rarely taken these benefits into consideration. Therefore, land use value has been greatly underestimated, which has resulted in mishandled and poor land use policies. In this study, we apply landsat imagery and social and economic statistical data for the Xi＇an metropolitan zone （XMZ） to investigate agricultural multi-functionality. We develop an evaluation framework for urban agricultural land use efficiency and identify agro-ecosystem services and functions as important outputs from agricultural land. The land use efficiency of urban agriculture is then evaluated using ecosystem services models, providing a mechanism for assessing spatial-temporal changes in land use efficiency in the XMZ from 1999 to 2015. Four important conclusions are reached from this analysis. First, the rapid urbanization and agricultural transformation from traditional cereal cultivation to modern urban agriculture has resulted in steadily increasing costs, out- puts, and land use efficiency of urban agriculture. The total output value increased 41% and land use efficiency p

关键词： urban agriculture land use efficiency agro-ecosystem services agricultural multi-functionality Xi＇an metropolitan zone （XMZ）

Spatiotemporal mismatch of land use functions and land use efficiencies and their influencing factors:A case study in the Middle Reaches of the Yangtze River,China

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Journal of Geographical Sciences 2024年第1期34卷 62-88页

作者： GAO Yunxiao WANG Zhanqi CHAI Ji ZHANG Hongwei School of Public Administration China University of GeosciencesWuhan 430074China

Identification of the spatial mismatch between land use functions(LUFs)and land use efficiencies(LUEs)is essential to regional land use policies.However,previous studies about LUF-LUE mismatch and its driving factors have been insufficient.In this study,we explored the spatiotemporal mismatch of LUFs and LUEs and their influencing factors from 2000 to 2018 in the Middle Reaches of the Yangtze River(MRYR).Specifically,we used Spearman correlation analysis to reveal the trade-off relationship between LUFs and LUEs and determine the direction of the influencing factors on the LUF-LUE mismatch,adopted spatial mismatch analysis to measure the imbalance between LUFs and LUEs,and used the geographical detector model to analyze the factors influencing this spatial mismatch.The results showed that production function(PDF),living function(LVF),ecological function(ELF),agricultural production efficiency(APE),urban construction efficiency(UCE),and ecological services efficiency(ESE)all displayed significant spatial heterogeneity.The high trade-off areas were widely distributed and long-lasting in agricultural space and urban space,while gradually decreasing in ecological space.Wuhan and Changsha showed high spatial mismatch coefficients in urban space,but low spatial mismatch coefficients in agricultural space.Hunan generally presented high spatial mismatch coefficients in ecological space.Furthermore,the interaction of the proportion of cultivated area and transportation accessibility exacerbated the mismatch in agricultural space.The interaction effects of capital investment and technology innovation with other factors have the most intense impact on the mismatch in urban space.The internal factor for cultivated area interacts with other external factors to drastically affect ecological spatial mismatch.

关键词： land use function land use efficiency spatial mismatch analysis influencing factors Middle Reaches of the Yangtze River

A Comparative Study on the land use efficiency of Three Urban Agglomerations-Based on the Three-Stage DEA Model

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Management Studies 2021年第3期9卷 190-202页

作者： Yang Lu Jiangxi University of Finance and Economics NanchangChina

This paper uses a three-stage DEA model to measure the land use efficiency of the three major urban agglomerations in the Yangtze River Delta,Beijing-Tianjin-Hebei,and the Pearl River Delta from 2007 to 2018.The following conclusions are drawn through research:first,the urban land use efficiency of the three major urban agglomerations in the Yangtze River Delta,Beijing-Tianjin-Hebei,and the Pearl River Delta all showed a downward trend,with the rates of decline being 6.06%,2.86%,and 24.34%respectively.In particular,the Pearl River Delta urban agglomeration had the largest decline.Second,the overall urban land use efficiency of the Beijing-Tianjin-Hebei urban agglomeration is relatively high,and the amount of redundancy is relatively small.The rate of decline is significantly lower than the urban land use efficiency of the two major urban agglomerations in the Yangtze River Delta and the Pearl River Delta.The land use efficiency of the Yangtze River Delta and Pearl River Delta urban agglomerations is in a state of continuous decline.Third,the proportion of cities with the effectiveness of returns to scale of urban land use efficiency in the three major urban agglomerations has decreased by 10.53%,10%,and 33.34%,respectively.The Pearl River Delta has the largest decline.Fourth,the land use efficiency of the Yangtze River Delta urban agglomeration is quite different.The central-peripheral phenomenon is evident for the Beijing-Tianjin-Hebei urban agglomerations and the Pearl River Delta urban agglomerations.

关键词： three-stage DEA model three city groups land use efficiency

Water, land, and energy use efficiencies and financial evaluation of air conditioner cooled greenhouses based on field experiments

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Journal of Arid land 2021年第4期13卷 375-387页

作者： Ibtihal AL-MANTHRIA Abdulrahim M AL-ISMAILIA Hemesiri KOTAGAMAB Mumtaz KHANC L H Janitha JEEWANTHAD Department of Soils Water and Agricultural EngineeringSultan Qaboos UniversityMuscat PC123Oman Department of Natural Resource Economics Sultan Qaboos UniversityMuscat PC123Oman Department of Plant Science College of Agricultural and Marine SciencesSultan Qaboos UniversityMuscat PC123Oman Centre for Future Materials University of Southern QueenslandToowoomba QLD 4350Australia School of Mechanical and Electrical Engineering University of Southern QueenslandToowoomba QLD 4350Australia

High temperature and humidity can be controlled in greenhouses by using mechanical refrigeration cooling system such as air conditioner(AC)in warm and humid regions.This study aims to evaluate the techno-financial aspects of the AC-cooled greenhouse as compared to the evaporative cooled(EV-cooled)greenhouse in winter and summer seasons.Two quonset single-span prototype greenhouses were built in the Agriculture Experiment Station of Sultan Qaboos University,Oman,with dimensions of 6.0 m long and 3.0 m wide.The AC-cooled greenhouse was covered by a rockwool insulated polyethylene plastic sheet and light emitting diodes(LED)lights were used as a source of light,while the EV-cooled greenhouse was covered by a transparent polyethylene sheet and sunlight was used as light source.Three cultivars of high-value lettuce were grown for experimentation.To evaluate the technical efficiency of greenhouse performance,we conducted measures on land use efficiency(LUE),water use efficiency(WUE),gross water use efficiency(GWUE)and energy use efficiency(EUE).Financial analysis was conducted to compare the profitability of both greenhouses.The results showed that the LUE in winter were 10.10 and 14.50 kg/m^(2) for the AC-and EV-cooled greenhouses,respectively.However,the values reduced near to 6.80 kg/m^(2) in both greenhouses in summer.The WUE of the AC-cooled greenhouse was higher than that of the EV-cooled greenhouse by 3.8%in winter and 26.8%in summer.The GWUE was used to measure the total yield to the total greenhouse water consumption including irrigation and cooling water;it was higher in the AC-cooled greenhouse than in the EV-cooled greenhouse in both summer and winter seasons by almost 98.0%–99.4%.The EUE in the EV-cooled greenhouse was higher in both seasons.Financial analysis showed that in winter,gross return,net return and benefit-to-cost ratio were better in the EVcooled greenhouse,while in summer,those were higher in the AC-cooled greenhouse.The values of internal rate of return in the AC-and EV-cooled greenhouses wer

关键词： land use efficiency energy use efficiency water use efficiency gross water use efficiency financial evaluation air conditioner cooled greenhouse evaporative cooled greenhouse

The Ecological Effects of Young Elm Trees Belt-Pumpkin Strip Intercropping System at the Agro-Pastoral Ecotone in Northern China

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Agricultural Sciences in China 2010年第8期9卷 1183-1193页

作者： DU Xiong DOU Tie-ling FENG Li-xiao ZHANG Wei-hong ZHANG Li-feng College of Agronomy Agricultural University ofHebei Baoding 071001 P.R.China Zhangbei Agricultural Resource and Ecological Environment Key Field Research Station Ministry of Agriculture Zhangjiakou 076450 P. R. China College of Plant Protection Agricultural University of Hebei Baoding 071001 P.R. China

Young elm trees belt-pumpkin strip intercropping was studied to solve the actual problem of resource losses in the large barren area resulted from reconverting cultivated land into forest in the agro-pastoral ecotone in northern China. The final objective was to realize effective utilization of the barren land with both ecological improvement and economic development. Field experiments were conducted together with laboratory analysis. The results indicated that the soil moisture level was remarkably increased in young elm trees belt-pumpkin strip intereropping because the pumpkin vines covered the gap between pumpkin planting-furrow and elm trees belt. The water use efficiency of the intercropping system was increased by 23.7-163.3% as compared with the single cropping. Elm trees belt-pumpkin strip intercropping changed the sequential succession trend of the grasses growing in the gap of the pumpkin planting-furrow. The annual grasses become the dominant vegetation. The nutritive value as fodder and yield of the annual grasses were also increased remarkably. The biomass of pumpkin, elm trees and grasses under intercropping increased by 24.4, 28.4 and 144.4%, respectively, as compared with those under single cropping. The land use efficiency was increased by 132%. It was also indicated that the soil erosion from the intercropping land was not increased due to pumpkin plantation. The differences in the soil erosion among intercropped area, elm trees belt and pumpkin strip with single cropping were not remarkable. Therefore, it was concluded that young elm trees belt-pumpkin strip intercropping is an effective way to utilize the barren land between the young elm trees belt and realize synergistic enhancement of ecological benefit and economic profit.

关键词： ecotone young elm trees belt-pumpkin strip intercropping water use efficiency land use efficiency ecological benefit economic profit

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政府主导型城市化的土地利用效率

农业经济研究