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An agent-based model of agricultural land expansion in the mountain forest of Timor Island,Indonesia
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作者 PUJIONO Eko SADONO Ronggo +12 位作者 IMRON Muhammad Ali SUTOMO JANUAR Hedi Indra KUSWANDI Relawan KURNIAWAN Hery HADI Etik Erna Wati SAPUTRA Muhammad Hadi HIDAYAH Izhamil HUMAIDA Nida SUKMAWATI Jalma Giring HADIYAN Yayan NUGROHO Agung Wahyu HANI Aditya 《Journal of Mountain Science》 SCIE CSCD 2024年第7期2263-2282,共20页
The Mutis-Timau Forest Complex,located on Timor Island,Indonesia,is a mountainous tropical forest area that gradually decreases due to deforestation and forest degradation.Previous modelling studies based on patterns ... The Mutis-Timau Forest Complex,located on Timor Island,Indonesia,is a mountainous tropical forest area that gradually decreases due to deforestation and forest degradation.Previous modelling studies based on patterns indicate that deforestation primarily occurs at lower elevations and near the boundaries of forests and settlements,often associated with shifting cultivation by local farmers.This study adopts a process-based modelling approach,specifically the agent-based model,to simulate land changes,particularly farmers'expansion of agricultural land around the Mutis mountain forest.The underlying concept of this agent-based approach is the interaction between the human and environmental systems.Farmers,representing the human system,interact with the land,which represents the environmental system,through land use decision-making mechanisms.The research was conducted in the Community Forest of the Timor Tengah Utara District,one of the sites within the Mutis-Timau Forest Complex with the highest deforestation rate.Land use change simulations were performed using agent-based modelling from 1999 to 2030,considering the socio-economic conditions of farmers,spatial preferences,land use decisions,and natural transitions.The results revealed that the agricultural area increased by 14%under the Business as Usual scenario and 5%under the Reducing Emission from Deforestation and Forest Degradation scenario,compared to the initial agricultural area of 245 hectares.The probability of farmers deciding to extend agricultural activities was positively associated with the number of livestock maintained by farmers and the size of the village area.Conversely,the likelihood of farmers opting for agricultural extensification decreased with an increase in the area of private land and the farmer's age.These findings are crucial for the managers of the Mutis-Timau Forest Complex and other relevant stakeholders,as they aid in arranging actions to combat deforestation,designing proper forest-related policies,and providing support for initiatives such as reducing emissions from deforestation and forest degradation programs or further incentive schemes. 展开更多
关键词 Agricultural land expansion Simulation Agent-based model FARMER DEFORESTATION Mountainous tropical forest
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Can Industrial Structure Upgrading Restrain Industrial Land Expansion?Evidence from China
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作者 CHEN Wei LI Qiao +1 位作者 ZHANG Sun ZHOU Xue 《Chinese Geographical Science》 SCIE CSCD 2024年第3期504-518,共15页
China has made great achievements in industrial development and is transforming into a powerful manufacturing country.Meanwhile,the industrial land scale is also expanding.However,whether industrial structure upgradin... China has made great achievements in industrial development and is transforming into a powerful manufacturing country.Meanwhile,the industrial land scale is also expanding.However,whether industrial structure upgrading achieves the purpose of restraining industrial land expansion remains unanswered.By calculating the industrial land structure index(ILSI)and industrial land expansion scale(ILES),this study analyzed their temporal and spatial distribution characteristics at both regional and city levels from 2007to 2020 in China.Results show that industrial land expansion presents a different trend in the four regions,the ILES in the eastern region is the largest,and the speed of industrial land expansion has declined since 2013,but it has gradually increased since 2016.The ILSI of the eastern and central regions is higher than that of the western and northeastern regions.Furthermore,a spatial Durbin model(SDM)has been established to estimate the spatial effect of industrial structure upgrading on industrial land expansion from 2007 to2020.Notably,industrial structure upgrading has not slowed industrial land expansion.The eastern and western regions require a greater amount of industrial land while upgrading the industrial structure.The improvement of the infrastructure level and international trade level has promoted industrial land expansion. 展开更多
关键词 industrial development industrial structure upgrading industrial land expansion regional differences China
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Construction land expansion and influencing factors of typical river valley cities in Northeast China: Taking Jilin City as an example
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作者 LI Ruiqi LI Hong YIN Jingbo 《Global Geology》 2023年第3期189-198,共10页
Jilin City is a typical river valley city in Northeast China.In this paper,the authors studied the spatial and temporal expansion characteristics of the built-up areas in Jilin City from 1990 to 2020 using the analysi... Jilin City is a typical river valley city in Northeast China.In this paper,the authors studied the spatial and temporal expansion characteristics of the built-up areas in Jilin City from 1990 to 2020 using the analysis of expansion speed and strength,fractal dimension,barycenter coordinate transfer index and sector analysis.The ultimate-goal is to analyze the driving and restrictive factors that affect the spatial expansion of river valley cities.The results indicate that(1)the expansion speed of urban land in Jilin City has been re-latively slow in the past 30 years,while only slightly faster in 2010–2020;(2)in the spatial dimension,Jilin City mainly expanded to the south,then to the west,and extensive expansion has resulted in complex mor-phology with little stability and compactness;(3)the expansion is affected by multiple factors,of which the positive factor is industrial development,while the restrictive factors include natural factors,population loss,etc.This study provides a case for the formulation of land use policies and land space planning in river valley cities. 展开更多
关键词 river valley city expansion of construction land influencing factors Jilin City
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The influencing factors of urban land expansion in Changsha 被引量:9
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作者 ZHOU Guohua HE Yanhua 《Journal of Geographical Sciences》 SCIE CSCD 2007年第4期487-499,共13页
This research systematically analyses land-use map of Changsha city in different periods of time. The spatial form and structural evolution was analysed by studying indices such as city land-use structure proportion, ... This research systematically analyses land-use map of Changsha city in different periods of time. The spatial form and structural evolution was analysed by studying indices such as city land-use structure proportion, expansion intensity, economic flexibility, population flexibility, changing compactness index and so on. The dynamic mechanism of urban land expansion has been discussed by integrating the regional social economy development situation and many aspects such as the physiographical surrounding, population and economic development, traffic infrastructure, planning and regional development tactic and system innovation. The research indicates that the urban land expansion speed and intensity have steadily increased in Changsha from 1949 to 2004. The expansion form has been from a single external expansion to a combination form of external and internal expansion, from a circular or linear continuous form to a blocky or agglomeration shape. Overall, the urban land expansion of Changsha city is a phasic, diversified and complex process. And no matter what the stage is, it is an organic system containing multiple speed, pattern and shape, which are driven by multiple impetuses. The dominant feature at different stages was highlighted because of the balance and fluctuation between different forces, and the existing urban land border and shape have resulted from the joint efforts of these phasic forces. 展开更多
关键词 Changsha urban land expansion influencing factors dynamic mechanism
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Urban Expansion and Its Influencing Factors in Natural Wetland Distribution Area in Fuzhou City,China 被引量:8
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作者 CAI Yuanbin ZHANG Hao +2 位作者 PAN Wenbin CHEN Yanhong WANG Xiangrong 《Chinese Geographical Science》 SCIE CSCD 2012年第5期568-577,共10页
This paper principally focuses on land use dynamics,urban expansion and underlying driving forces in the Natural Wetland Distribution Area(NWDA)of Fuzhou City in the southeastern China.Based on time series Landsat TM/... This paper principally focuses on land use dynamics,urban expansion and underlying driving forces in the Natural Wetland Distribution Area(NWDA)of Fuzhou City in the southeastern China.Based on time series Landsat TM/ETM+imageries and historical data,relationships between urban land expansion and its influencing factors from 1989 to 2009 were analyzed by using an integrated approach of remote sensing(RS)and geographic information system(GIS)techniques.The results showed that built-up land increased from 151.16 km2in 1989 to 383.76 km 2in 2009. Approximately 64.25%of the newly emerging built-up land was converted from cropland(29.47%),forest and shrub (25.78%),water(3.73%),wetland(4.61%),and bare land(0.66%)during 1989 and 2009.With a remarkable decrease in cropland,the proportion of non-agricultural population increased by 23.6%.Moreover,rapid development of infrastructures,facilities,industrial parks,and urban and rural settlements along the Minjiang River resulted in the eastward and southward expansion of built-up land.Additionally,the growth pattern of built-up land in the NWDA is highly correlated with socio-economic factors,including the gross domestic product(GDP),GDP per capita,and structure of industry.As a result,the observed environmental degradation such as loss of cropland and wetland due to heavy pressure of rapid urbanization have greatly impaired the carrying capacity of city.Thus,in addition to scientific and rational policies towards minimizing the adverse effects of urbanization,coordination between the administrative agencies should be urgently strengthened to balance the conflicts between urban development and ecological conservation to make sure the sustainable land use. 展开更多
关键词 land use urban expansion natural wetland socio-economic factors remote sensing (RS) geographic in-formation system (GIS)
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Simulation of Urban Land Expansion Under Ecological Constraints in Harbin-Changchun Urban Agglomeration,China 被引量:5
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作者 GUO Rong WU Tong +2 位作者 WU Xiaochen LUIGI Stendardo WANG Yueqin 《Chinese Geographical Science》 SCIE CSCD 2022年第3期438-455,共18页
Under the demand of urban expansion and the constraints of China’s’National Main Functional Area Planning’policy,urban agglomerations are facing with a huge contradiction between land utilization and ecological pro... Under the demand of urban expansion and the constraints of China’s’National Main Functional Area Planning’policy,urban agglomerations are facing with a huge contradiction between land utilization and ecological protection,especially for HarbinChangchun urban agglomeration who owns a large number of land used for the protection of agricultural production and ecological function.To alleviate this contradiction and provide insight into future land use patterns under different ecological constraints’scenarios,we introduced the patch-based land use simulation(PLUS)model and simulated urban expansion of the Harbin-Changchun urban agglomeration.After verifying the accuracy of the simulation result in 2018,we predicted future urban expansion under the constraints of three different ecological scenarios in 2026.The morphological spatial pattern analysis(MSPA)method and minimum cumulative resistance(MCR)model were also introduced to identify different levels of ecological security pattern(ESP)as ecological constraints.The predicted result of the optimal protection(OP)scenario showed less proportion of water and forest than those of natural expansion(NE)and basic protection(BP)scenarios in 2026.The conclusions are that the PLUS model can improve the simulation accuracy at urban agglomeration scale compared with other cellular automata(CA)models,and the future urban expansion under OP scenario has the least threat to the ecosystem,while the expansion under the natural expansion(NE)scenario poses the greatest threat to the ecosystem.Combined with the MSPA and MCR methods,PLUS model can also be used in other spatial simulations of urban agglomerations under ecological constraints. 展开更多
关键词 urban land expansion patch-based land use simulation(PLUS)model Harbin-Changchun urban agglomeration scenario simulation ecological constraints China
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Expansion of Urban Space and Land Use Control in the Process of Urbanization: an Overview 被引量:6
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作者 Dai Junliang Gao Xiaolu Du Shoushuai 《Chinese Journal of Population,Resources and Environment》 2010年第3期73-82,共10页
Urban expansion brought by the rapid progress of urbanization has caused many problems in China. It is a significant issue to evaluate the extent of urban expansion and to make appropriate controls over the sprawl of ... Urban expansion brought by the rapid progress of urbanization has caused many problems in China. It is a significant issue to evaluate the extent of urban expansion and to make appropriate controls over the sprawl of urban areas. With a comparative study of international experiences, this article analyzed the mechanism and consequences of urban expansion, reviewed the typical planning and financial policies adopted by other countries for controlling urban sprawl, and discussed the suitable densities of urban areas. The analysis results suggested that Chinese cities have no better choice but compact urban forms. To achieve the goal of compact development, intensive use of public transportation and high proportion of collective houses should be encouraged, and 60–100 m2 per capita is recommended as the reasonable range of urban density in large cities. 展开更多
关键词 urban expansion urban sprawl smart growth land use quota
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Evaluating and modeling the spatiotemporal pattern of regional-scale salinized land expansion in highly sensitive shoreline landscape of southeastern Iran 被引量:1
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作者 Mohammad SHAFIEZADEH Hossein MORADI Sima FAKHERAN 《Journal of Arid Land》 SCIE CSCD 2018年第6期946-958,共13页
Taking an area of about 2.3×10~4 km~2 of southeastern Iran, this study aims to detect and predict regional-scale salt-affected lands. Three sets of Landsat images, each set containing 4 images for 1986, 2000, and... Taking an area of about 2.3×10~4 km~2 of southeastern Iran, this study aims to detect and predict regional-scale salt-affected lands. Three sets of Landsat images, each set containing 4 images for 1986, 2000, and 2015 were acquired as the main source of data. Radiometric, atmospheric and cutline blending methods were used to improve the quality of images and help better classify salinized land areas under the support vector machine method. A set of landscape metrics was also employed to detect the spatial pattern of salinized land expansion from 1986 to 2015. Four factors including distance to sea, distance to sea water channels, slope, and elevation were identified as the main contributing factors to land salinization. These factors were then integrated using the multi-criteria evaluation (MCE) procedure to generate land sensitivity map to salinization and also to calibrate the cellular-automata (CA) Markov chain (CA-Markov) model for simulation of salt-affected lands up to 2030, 2040 and 2050. The results of this study showed a dramatic dispersive expansion of salinized land from 7.7 % to 12.7% of the total study area from 1986 to 2015. The majority of areas prone to salinization and the highest sensitivity of land to salinization was found to be in the southeastern parts of the region. The result of the MCE-informed CA-Markov model revealed that 20.3% of the study area is likely to be converted to salinized lands by 2050. The findings of this research provided a view of the magnitude and direction of salinized land expansion in a past-to-future time period which should be considered in future land development strategies. 展开更多
关键词 soil salinization remote sensing CA-Markov salt land expansion southeastern Iran
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Analyzing and Pondering on the Regulation of Urban Construction Land Expansion 被引量:1
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作者 Zhang Wei Zhang Hongye Zhang Yifeng 《Chinese Journal of Population,Resources and Environment》 2009年第4期46-50,共5页
Along with the economic development and the acceleration of urbanization,urban construction land expands rapidly in China,and has resulted in a series of socio-economic problems.This article summarized the major point... Along with the economic development and the acceleration of urbanization,urban construction land expands rapidly in China,and has resulted in a series of socio-economic problems.This article summarized the major points of controlling the unchecked and rash expansion of construction land in the academic circle,and analyzed the problems of regulating the expansion of construction land from three aspects.First,this article analyzed the relationships between socio-economic development and urbanization from the historical viewpoints,and pointed out that the expansion of construction land is a historical phenomenon which will be surely appeared in the development of human race.Second,the authors utilized two-sector model to analyze the importance of urbanization in the socio-economic development from the academic angles.At last,the authors utilize four-quadrant model and bidrent curve model to analyze the influence that brought by the strict control of construction land expansion.Through analysis,this article drew some conclusions.First,the expansion of construction land is a phenomenon which will surely appear in the social development.It is impossible to accomplish the national modernization on the basis of dualistic structure between urban and rural areas.Second,under the function of rent gradient gap,strict control of construction land expansion will not only obtain the anticipated effects,but also cause a series of socio-economic problems,such as land-levying contradiction,the appearance of limited property right house,and being dependant on lease instead of expropriation.Third,unreasonable policies and governmental behaviors are the roots of the unchecked and rash expansion of urban construction land.Based on these conclusions,this article proposed that three transformations should be realized to regulate the unchecked and rash expansion of construction land:transfers from quantity regulation to quality regulation,from direct regulation to indirect regulation,and from single-measure regulation to multi-measures regulation. 展开更多
关键词 urban construction land expansion REGULATION academic analysis
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Spatio-temporal Evolution of Urban Expansion Based on a Novel Adjusted Index and GEE: A Case Study of Central Plains Urban Agglomeration, China
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作者 SU Yanlin LU Chunyan +3 位作者 SU Yue WANG Zili HUANG Yufei YANG Nuocheng 《Chinese Geographical Science》 SCIE CSCD 2023年第4期736-750,共15页
It is crucial to investigate the urban agglomerations spatio-temporal evolution patterns and driving factors for analyzing the urban spatial structure-functional division and promoting the coordinated development of u... It is crucial to investigate the urban agglomerations spatio-temporal evolution patterns and driving factors for analyzing the urban spatial structure-functional division and promoting the coordinated development of urban agglomerations.In this study,a novel vegetation-building-nighttime light-adjusted index(VBNAI)was established for rapid and effective mapping of urban construction land(UCL)in Central Plains Urban Agglomeration(CPUA),China during 2000–2020 based on Google Earth Engine(GEE)platform.Compared with traditional indices,VBNAI can significantly decrease the blooming effect,Normalized Difference Vegetation Index(NDVI)saturation,and soil background of nighttime light data.In addition,the urban expansion indices and standard deviation ellipse model were synthetically adopted to analyze the spatio-temporal evolution pattern of urban expansion.The gravity model and the geographically weighted regression model were employed to determine the spatial interaction forces and drivers of urban expansion,respectively.The results showed that the VBNAI index has obvious advantages in efficiency and accuracy to extract UCL with the overall accuracy of more than 91%.The UCL of CPUA had increased by 4489.84 km2 during 2000–2020 with the gravity center moving towards southeast continuously.From 2000 to 2010,the urban expansion was in a‘center-hinterland’pattern which had benefit from the favorable effect of the traffic shaft belt.During 2010–2020,the urban network structure had basically established.Urban expansion had been influenced by a variety of socio-economic and demographic factors,and the impact degree varied from region to region.This study could provide scientific references for facilitating the intensive utilization of urban resources and optimizing the spatial development pattern of urban agglomeration. 展开更多
关键词 urban expansion urban construction land(UCL)mapping vegetation-building-nighttime light-adjusted index(VBNAI) multi-source remote sensing Google Earth Engine(GEE) Central Plains Urban Agglomeration(CPUA) China
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Non-agricultural Population, Employment and Land:An Econometric Study in an Integrated Framework
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作者 Hu Weiyan Zhang Anlu Liu Caixia 《Chinese Journal of Population,Resources and Environment》 2009年第1期65-75,共11页
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
关键词 non-agricultural population non-agricultural employment non-agricultural land
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Government's Role in Urban Construction Land Expansion
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作者 CHEN Chun FENG Chang-chun 《Asian Agricultural Research》 2010年第8期44-48,52,共6页
Focusing on urban construction land expansion,governmental influence on expansion of urban construction land in China is analyzed from fiscal decentralization,government game and land system.Due to fiscal decentraliza... Focusing on urban construction land expansion,governmental influence on expansion of urban construction land in China is analyzed from fiscal decentralization,government game and land system.Due to fiscal decentralization and coupled with GDP-based performance evaluation system,local government seeks to maximizing economic profits.Whereas,land systems such as land property,land expropriation and land transfer system,let the local governments' profit seeking behavior achieved.The conclusion is that the government's role in urban construction land expansion is mainly from local governments. 展开更多
关键词 Urban construction land land expansion Local governments land system China
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On the Distributive Justice of Land Added Value in the Process of Urban Expansion
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作者 Zeyi ZHANG 《Asian Agricultural Research》 2014年第5期55-59,共5页
It is an unarguable fact that the urban-rural dual structure led to two different results. On the one hand,it had been playing a great role in the city development and prosperity,and on the other hand,it had led the s... It is an unarguable fact that the urban-rural dual structure led to two different results. On the one hand,it had been playing a great role in the city development and prosperity,and on the other hand,it had led the slow development of rural economy and the income gap between rural and urban areas. The government makes efforts to promote the process of urbanization to maintain the sustained development of China's economy and economic transformation which are the two needs of the Chinese reality. But in the top-level design of the policy,the government did not give a fair profits distribution to all social groups. On the contrary,the result of urban development is based on the expense of a part of the people's interests in exchange for the interests of another parts of the people,and especially on the government expropriation in the process of urban expansion. Under Land Administration Law of the People's Republic of China,the government monopolized the expropriation right of the rural land,and the rural collectives and farmers as the land owner and constructors respectively have no rights to decide the land use purposes. In fact,they are forced to accept the land compensation,and because of the little bargaining rights,they gain little from the land value increment. Comparatively,the governments became the biggest beneficiary who made use of the land as a source and capital to earn the achievement in their official career and more money required by the urban development. The paper mainly analyzes the current situation of the distribution of the land added value,elaborates the reasons why the government strives for the land interests,and discusses what farmers lose in the government expropriation. Last but not lest,the author reflects on the land reform and gives a proposal on distribution of land added value. 展开更多
关键词 land added VALUE DISTRIBUTIVE JUSTICE URBAN expans
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Importance and Countermeasures of Curbing the Conversion of Agricultural Land to Non-agricultural Land under the Background of the Rural Revitalization Strategy
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作者 Mingqian JIN Zisheng YANG 《Asian Agricultural Research》 2021年第11期27-31,共5页
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
关键词 Rural revitalization strategy Conversion of agricultural land to non-agricultural land COUNTERMEASURES
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Quinoa Expansion in Peruvian Departments and Land Use Change before the Health Crisis
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作者 Jhon Huillca Baldomero Segura Aquilino Álvarez 《Agricultural Sciences》 2021年第8期827-843,共17页
National and international policies have promoted quinoa consumption, influencing the expansion of the crop, and generating changes in land use. In this article, we analyzed the evolution of quinoa cultivation in Peru... National and international policies have promoted quinoa consumption, influencing the expansion of the crop, and generating changes in land use. In this article, we analyzed the evolution of quinoa cultivation in Peru both at the national and departmental levels. Time series analysis vas used to. Between 1951 and 2019, the evolution of the quinoa-harvested areas in Peru has gone through various stages, first in regression until 1990, and then it has experienced a growth rate of 10%. Puno is still by far the department where the crop is most widespread. Taking into account the geographical and technological conditions, this highland area is less likely to maintain the rate of expansion than the Peruvian coast, which will imply great challenges for Andean farmers who have maintained the traditional crop throughout the period. 展开更多
关键词 QUINOA land Use expansion Rate Time Series Traditional Zones
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Variations in Soil Organic Matter Content in Cultivated and Uncultivated Calcareous Soils from the Mediterranean Island of Malta after 15 Years of Cultivation
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作者 Anthony T. Sacco Marcelle Agius Clara Didier 《Open Journal of Soil Science》 2024年第4期210-226,共17页
The soils of Malta are calcareous and generally undeveloped. Organic matter (OM) in these soils is low and farmers are constantly urged to increase it. The objective of this study was to evaluate any temporal variatio... The soils of Malta are calcareous and generally undeveloped. Organic matter (OM) in these soils is low and farmers are constantly urged to increase it. The objective of this study was to evaluate any temporal variation in soil OM after 15 years of cultivation, and determine whether soil series, soil depth, and cultivation influence variation. OM was determined in the topsoil and subsoil of 7 agricultural and 4 non-agricultural sites. The sites represented 7 different soil series that are present on the island. In sampling periods 1 (t = 0 years) and 2 (t =15 years), the OM content in the collective (all soil series) bulk (topsoil and subsoil) uncultivated soil was 3.9 % and 3.8 % respectively. This was significantly greater than that of the collective bulk cultivated soil (2.4% and 2.3%). The OM in the collective uncultivated topsoil was 5.4% and 5.2% in periods 1 and 2 and was significantly higher than that of the cultivated topsoil (2.5% in both periods). The OM content in the collective uncultivated subsoil was 2.3% and 2.5% in periods 1 and 2 respectively but only that measured in period 2 was significantly higher than that of the cultivated subsoil (2.2% in both periods). On an individual soil series basis, the OM in the uncultivated topsoils was significantly higher than that of their cultivated counterparts. The differences in the subsoils were not significant. Across the uncultivated soil series, OM was significantly higher in the topsoil than in the subsoil but in the cultivated soil series the differences between topsoil and subsoil were not significant. There was no significant difference in OM between the uncultivated soils of different series, but in the cultivated the OM content was higher in soils that were more mature. After 15 years, no significant change in OM occurred in both the collective cultivated and uncultivated bulk soils, the collective topsoil and subsoil, and in most of the individual series. The OM content of each soil series was also similar to what was reported 60 and 50 years earlier by other researchers. 展开更多
关键词 Soil Organic Carbon Agricultural land non-agricultural land land Management
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Expansion of traditional land-use and deforestation:a case study of an adat forest in the Kandilo Subwatershed,East Kalimantan,Indonesia
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作者 Hunggul Y.S.H.Nugroho Anne van der Veen +1 位作者 Andrew K.Skidmore Yousif A.Hussin 《Journal of Forestry Research》 SCIE CAS CSCD 2018年第2期488-506,共19页
Deforestation issues are more problematic when indigenous(adat) communities,living within a forest,have lived there for many generations.These adat communities,who employ traditional land-use,are frequently accused of... Deforestation issues are more problematic when indigenous(adat) communities,living within a forest,have lived there for many generations.These adat communities,who employ traditional land-use,are frequently accused of encroaching on the forest.To understand existing and future trends in the spatial patterns of the expansion of traditional land-use and deforestation,we conducted a case study in the Kandilo Subwatershed using mixed methods with image interpretation,spatial modelling and sociocultural surveys to examine the interrelationships between physical conditions,community characteristics and traditional land-use expansion.We investigated community characteristics through household interviews,communication with key informants,and discussions with focusgroups.By using an area production model,we were able to analyze the effect of improved farming systems,policy intervention and law enforcement on traditional land-use expansion and deforestation.Based on our examination of a 20-year period of traditional land-use activities in adat forests,the evidence indicated that the steeper the slope of the land and the farther the distance from the village,the lower the rate of deforestation.Our study found that customary law,regulating traditional land-use,played an important role in controlling deforestation and land degradation.We conclude that the integration of land allocation,improved farming practices and enforcement of customary law are effective measures to improve traditional land productivity while avoiding deforestation and land degradation. 展开更多
关键词 Adat people Agriculture expansion Area production model(APM) Customary law DEFORESTATION Traditional land-use
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Modelling urban expansion using a multi agentbased model in the city of Changsha 被引量:12
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作者 ZHANG Honghui ZENG Yongnian +1 位作者 BIAN Ling YU Xijun 《Journal of Geographical Sciences》 SCIE CSCD 2010年第4期540-556,共17页
Although traditional urban expansion simulation models can simulate dynamic features, these models fail to address complex changes produced by different agents' behaviors. The paper has built up a set of spatial-temp... Although traditional urban expansion simulation models can simulate dynamic features, these models fail to address complex changes produced by different agents' behaviors. The paper has built up a set of spatial-temporal land resource allocation rules and developed a dynamic urban expansion model based on a multi-agent system, which can simulate the interaction among different agents, such as residents, peasants, and governments. This model is applied to simulate urban expansion process taking Changsha City, in China as a study area. The results show that this model can not only reflect basic characteristics of urban expansion, but also help explain the reasons for urban expansion process and understand the effect of agents' behavior on the expansion process, and provide insights into the causing factors behind the expansion. In addition, in contrast to simulation results with land use classification map from remote sensing images, the precision of the simulation reached over 68% with higher precision than cellular automata model according to the cell-by-cell comparison. The results suggest that the model can help to provide land use decision making support to government and urban planners. 展开更多
关键词 multi-agent system cellular automata urban expansion land resource allocation Changsha
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Characterizing urban expansion of Korla City and its spatial-temporal patterns using remote sensing and GIS methods 被引量:5
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作者 Bumairiyemu MAIMAITI DING Jianli +1 位作者 Zibibula SIMAYI Alimujiang KASIMU 《Journal of Arid Land》 SCIE CSCD 2017年第3期458-470,共13页
Cities provide spatial contexts for populations and economic activities. Determining the spatial-temporal patterns of urban expansion is of particular significance for regional sustainable development. To achieve a be... Cities provide spatial contexts for populations and economic activities. Determining the spatial-temporal patterns of urban expansion is of particular significance for regional sustainable development. To achieve a better understanding of the spatial-temporal patterns of urban expansion of Korla City, we explore the urban expansion characteristics of Korla City over the period 1995-2015 by employing Landsat TM/ETM+ images of 1995, 2000, 2005, 2010, and 2015. Urban land use types were classified using the supervised classification method in ENVI 4.5. Urban expansion indices, such as expansion area, expansion proportion, expansion speed, expansion intensity, compactness, and fractal dimension, were calculated. The spatial-temporal patterns and evolution process of the urban expansion (e.g., urban gravity center and its direction of movement) were then quantitatively analyzed. The results indicated that, over the past 25 years, the area and proportion of urban land increased substantially with an average annual growth rate of 15.18%. Farmland and unused land were lost greatly due to the urban expansion. This result might be attributable to the rapid population growth and the dramatic economic development in this area. The city extended to the southeast, and the urban gravity center shifted to the southeast as well by about 2118 m. The degree of urban compactness tended to decrease and the fractal dimension index tended to increase, indicating that the spatial pattern of Korla City was becoming loose, complex, and unstable. This study could provide a scientific reference for the studies on urban expansion of oasis cities in arid land. 展开更多
关键词 urban expansion spatial-temporal changes urban land remote sensing and GIS Korla City
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Water Cycle and Irrigation Expansion: An Application of Multi-Criteria Evaluation in the Limestone Coast (Australia)
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作者 Zahra Paydar Yun Chen 《Journal of Water Resource and Protection》 2014年第7期655-668,共14页
A summary of the current understanding of the hydrological system in the Limestone Coast in Australia is presented. The regional water balance analysis indicated about 90% of the water is lost through evapotranspirati... A summary of the current understanding of the hydrological system in the Limestone Coast in Australia is presented. The regional water balance analysis indicated about 90% of the water is lost through evapotranspiration. Irrigation consumes a substantial part of the groundwater and returns up to half of the water inflow to the aquifer. A multi-criteria analysis using fuzzy quantifiers and analytical hierarchy process was applied for future irrigation expansion. The results showed a total of 94,632 ha of land, considered suitable for irrigation where groundwater is not over-allocated or over used. This model showed some advantages over the conventional multi-criteria evaluation methods as it avoids arbitrary decisions on criteria weightings. 展开更多
关键词 land SUITABILITY Regional Water Balance IRRIGATION expansion MULTI-CRITERIA Evaluation
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