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Spatio-Temporal Assessment of Land Use Changes in Sonipat,Haryana:Socio Economic Impacts and Policy Intervention
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作者 Niraj Kumar Tejbir Singh Rana +1 位作者 Subhash Anand Nishit 《Research in Ecology》 2025年第3期309-334,共26页
This study examines the effects of rapid land use changes in India,with a specific focus on Sonipat District in Haryana—a region undergoing significant urban expansion.Over the past two decades,rural landscapes in So... This study examines the effects of rapid land use changes in India,with a specific focus on Sonipat District in Haryana—a region undergoing significant urban expansion.Over the past two decades,rural landscapes in Sonipat have undergone notable transformation,as open spaces and agricultural lands are increasingly converted into residential colonies,commercial hubs,and industrial zones.While such changes reflect economic development and urban growth,they also raise critical concerns about sustainability,especially in terms of food security,groundwater depletion,and environmental degradation.The study examines land use changes between 2000 and 2024 using remote sensing techniques and spatial analysis.It further incorporates secondary data and insights from community-level interactions to assess the socio-economic and ecological impacts of this transformation.The findings indicate rising land fragmentation,loss of agricultural livelihoods,pressure on civic infrastructure,and increasing pollution—factors that threaten long-term regional sustainability.The study underscores the urgent need to reconcile urban development with environmental and social sustainability.By offering a detailed case study of Sonipat,this research contributes to the broader discourse on India’s urbanisation pathways.It aims to provide policymakers,planners,and researchers with evidence-based recommendations to manage land transitions more responsibly,promoting urban growth models that ensure ecological integrity,equitable development,and long-term resilience. 展开更多
关键词 Land use Spatio-Temporal Dynamics Socio-Economic Impacts URBANIZATION policy
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A Corpus-Based Study on the Use Frequency of Large Numerals by Mandarin-Speaking Children
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作者 YANG Meiling DU Ailin 《Sino-US English Teaching》 2025年第6期189-195,共7页
The usage characteristics of the large numerals in child language reflects both linguistic and cognitive development.The present study systematically examined Mandarin children’s naturalistic use of large numerals“... The usage characteristics of the large numerals in child language reflects both linguistic and cognitive development.The present study systematically examined Mandarin children’s naturalistic use of large numerals“bai”,“qian”,and“wan”and compared it with adult usage patterns based on a self-constructed corpus.The results revealed a significant preference for the use of“bai”over both“qian”and“wan”among children and adults alike.This shared pattern suggests that children’s acquisition of large numerals is strongly shaped by adult language input.This study addresses a critical gap in research on the acquisition of large numerals by Mandarin-speaking children,providing valuable insights for the broader theoretical framework of cross-linguistic numerical cognition. 展开更多
关键词 large numerals child language use frequency corpus-based study
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Effects of China's National Essential Medicines Policy on the Use of Injection in Primary Health Facilities 被引量:5
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作者 向小曦 杨春艳 +2 位作者 王迪飞 叶菁 张新平 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2012年第4期626-629,共4页
The overuse of injection exists more than 20 years since economic reform in China.It is a persistent problem and seems becoming a new challenge in the new health reform period.This study was designed to assess the eff... The overuse of injection exists more than 20 years since economic reform in China.It is a persistent problem and seems becoming a new challenge in the new health reform period.This study was designed to assess the effect of national essential medicines policy(NEMP) on injection use at primary health facilities in China by investigating their prescription information.Questionnaires were designed and disseminated to collect empirical data on injection use at 120 primary health facilities in 6 provinces from January to September in 2010 and 2011.The injection use was measured as the indicator as the percentage of prescriptions with one or more injections.The results showed that the percentage of prescriptions with one or more injections was decreased from 38.91% to 36.82%(2 =11.158,P=0.001) in the all survey areas during the NEMP reform.The difference in level of the injection use in 2011 was significant among the eastern,central and western regions(2 =223.584,P=0.000);level of the injection use in western region was the lowest(27.73%),while that in the central region was the highest(43.10%).The level of the injection use in 2011 among different provinces was also of great difference(26.00%-58.25%,range:32.25%).The level of the injection use in 2011 was still much higher than the standard suggested by WHO for developing countries(13.4%-24.1%).It was concluded that NEMP has improved injection use in China,but the injection abuse situation remains serious,indicating that one of the priorities to the next stage of NEMP is to promote the rational use of drugs,especially the injection use. 展开更多
关键词 national essential medicines policy injection use primary health facilities China
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Land Use/Cover Change and Its Policy Implications in Typical Agriculture-forest Ecotone of Central Jilin Province,China 被引量:2
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作者 DONG Yulin REN Zhibin +3 位作者 FU Yao YANG Ran SUN Hongchao HE Xingyuan 《Chinese Geographical Science》 SCIE CSCD 2021年第2期261-275,共15页
During the 21st century,policies toward agriculture,forestry,and urbanization have emerged to ensure food security,ecological restoration,and human well-being by managing land in Northeast China.However,the integrated... During the 21st century,policies toward agriculture,forestry,and urbanization have emerged to ensure food security,ecological restoration,and human well-being by managing land in Northeast China.However,the integrated effects and relationships of various policies are still not well understood.This study observed the land use land cover changes in Central Jilin from 2000 to 2019 and,by considering policy involvement,aimed to understand the effects and trade-offs of policies.Results showed that the cropland,including dryland and rice paddy,and the forest,including coniferous forest and deciduous forest,are dominant land types in Central Jilin.During 2000–2019,the land changed diversely,of which the main changes were the expanded dryland(+0.43 million ha),the increased deciduous forest(+22 million ha),the decreased coniferous forest(–0.08 million ha),and the expanded urban settlement(+0.04 million ha).With these changes,despite the unit grain yield showing a rising trend,the yield contribution of Central Jilin to the national total decreased.The poor cultivating structure made for the cropland expansion and reduced the implementation space of environmental restoration projects such as the Grain to Green.Thus,in Central Jilin that transits from the agri-food production zone to the eco-regulation zone,environmental projects coexisted in a trade-off manner with agricultural policies that aim to liberate agricultural productivity.In the key urban agglomerations of Central Jilin,the increase in the proportion of green space improved the thermal environment and carbon balance.The gross domestic product of the large city and its local proportion also rose.These improvements benefited from the promotion of development policies and urbanization policies at key time points.In the future,it is necessary to coordinate agricultural policies and environmental projects and promote the progress of small-and medium-sized cities to ensure the equality of regional development.This study has implications for making decisions to revitalize Northeast China and researchers who inform decisions. 展开更多
关键词 land use land cover(LULC) policy agriculture-forest ecotone urbanization Northeast China
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Review of China's policy and management system for the paid use of sea area Feng 被引量:1
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作者 Feng Li Zenglei Xi Xiangbo Liang 《Chinese Journal of Population,Resources and Environment》 2019年第1期58-66,共9页
As a carrier to develop various marine resources, sea area is regulated as a kind of important resources through legislation by many coastal countries with a management system for the paid use of sea area. Since the e... As a carrier to develop various marine resources, sea area is regulated as a kind of important resources through legislation by many coastal countries with a management system for the paid use of sea area. Since the early 1990s, China has begun to implement the paid use and formed an institutional system comprised of three levels after developing it for more than two decades. From 2002 to 2015, the Chinese Government transferred the use right of sea area of 33,910 km2 by paid use and levied a total of 75.89 billion CNY (11.328 billion US dollars) of sea area use payment. Apart from this, the Government has gained rich experience in operating and managing the compensable use of sea area. After retrospectively analyzing the development history of paid use of China’s sea area, the research presents an institutional structure and the implementation of the management system for the paid use of sea area and the main problems therein. On this basis, management policies and feasible policy suggestions are proposed. Research results from this study can provide available references for other developing countries and emerging economies to apply and improve native management system for the paid use of sea area. 展开更多
关键词 PAID use SEA area policy management system China
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Optimization and Regulation Policy for Land Use Changes Based on Low-carbon Emission in Developed Regions of China 被引量:1
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作者 Degui YU Qun WU 《Asian Agricultural Research》 2017年第6期67-76,共10页
Land use and cover change(LUCC) is one of the important causes of the Earth’s carbon cycle imbalances resulting from failure in optimizing land use. The solution to this problem has been the hotspot of research in la... Land use and cover change(LUCC) is one of the important causes of the Earth’s carbon cycle imbalances resulting from failure in optimizing land use. The solution to this problem has been the hotspot of research in land and environmental science. We took 'low carbon', 'energy saving' and 'high-efficiency' as the goals of land use optimization,and integrated Markov-CA(Cellular Automaton),the Grid-Fractal model and GIS,in order to study carbon emission objective function,to establish a simulation method for land use spatial allocation optimization,to evaluate the effect of the method on carbon emissions. Regulation policy on three types of land use spatial allocation was proposed,including 'low-carbon type', 'low-carbon-economic type' and 'economic type'. We applied the method to analyze the land use spatial allocation in Taixing City of the 'Yangtze River Delta' regions in China,and obtained the following results:(i) The three optimization types would improve carbon emissions by 3. 21%,1. 80% and 0. 36% respectively in 2020,compared with 2010;(ii) The actual planning for 2020 was close to the 'low-carbon-economic type';(iii) The optimization method and regulation policy,combining local optimization and global control,could meet the sustainable multi-objective requirements for low-carbon constraints of land use spatial allocation. The result of this research could also serve as a reference for exploration into patterns of regional low-carbon land use and measures for energy saving and emission reduction. 展开更多
关键词 Regulation policy Land use optimization Low-carbon emission Markov-CA model Developed regions of China
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Impacts of the Benefit Sharing Mechanism(BSM)Policy Implementation on Forest Protection and Sustainable Use of Non-timber Products at Bach Ma National Park
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作者 Nguyen Van Loi Nguyen Vu Linh 《Journal of Agricultural Science and Technology(A)》 2017年第B10期68-77,共10页
This study aimed to evaluate the impacts of the benefit sharing mechanism(BSM)pilot policy on sustainable use of non-timber forest products(NTFPs)and natural resources conservation in co-management forest of Bach Ma N... This study aimed to evaluate the impacts of the benefit sharing mechanism(BSM)pilot policy on sustainable use of non-timber forest products(NTFPs)and natural resources conservation in co-management forest of Bach Ma National Park.Evaluation methods were route and permanent plot survey,household interview,in-depth interview,village meeting,group discussion and workshop at commune level.Results showed that:(1)the BSM policy had brought favorable conditions for local people in sustainable use and development of the NTFPs,as well as minimised the threats to biodiversity in co-managed forest;(2)the harvest amounts of seven selected NTFPs after two years of the BSM policy implementation were higher than growth rate of every NTFP and the permitted harvest amounts of the benefit sharing plans(BSP);(3)although there was a risk of over-exploitation of the NTFPs,the annual yields in 2013 and 2014 were much lower,but more sustainable than that before the BSM implementation;(4)the forest protection status in the co-management areas was also better than before.Additionally,this study has also defined and recommended that in order to continue the BSM,it is necessary to ensure the sustainable exploitation of NTFPs,as well as implement more enforcement activities inside the co-management forest area. 展开更多
关键词 BSM policy CO-MANAGEMENT non-timber forest products BACH MA National Park protection and SUSTAINABLE use
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Investigation of Climate and Land Use Policy Change Impacts on Food Security in Eastern Sudan, Gadarif State
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作者 Yousif Elnour Yagoub Zhongqin Li +3 位作者 Omer Said Musa Muhammad Naveed Anjum Feiteng Wang Zhang Bo 《Journal of Geographic Information System》 2017年第5期546-557,共12页
The aims of this research were to investigate the impacts of climate variations on land use policies, food security and vegetation cover in Gadarif State (eastern Sudan) during 1961 to 2013. Analysis of precipitation ... The aims of this research were to investigate the impacts of climate variations on land use policies, food security and vegetation cover in Gadarif State (eastern Sudan) during 1961 to 2013. Analysis of precipitation and temperature time series revealed that the annual precipitation was decreasing while the temperature was increased in the study area. Precipitation was decreasing at a rate of &minus;50.3 mm/10a, while the temperature was increasing at a rate of 0.02°C/10a. The result of both SPEI and SPI showed that the Gadarif State has been changed to a high frequency of drought during 1961-2013. Sorghum yield showed a significant positive relationship with precipitation during July and October (CC = 0.364 and 0.321, respectively), moreover, a significant positive relationship between Sesame yield and precipitation was observed during July (CC = 0.335). A significant negative relationship between Sorghum yield and mean temperature was observed during the rainy season (July to October) with CC = &minus;0.278. The yield productivity of Sorghum and Sesame had decreased significantly (from more than 800 kg/ha in the 1960s to less than 200 kg/ha in 2000s for Sorghum, while 500 kg/ha in 1960s to 100 kg/ha in 2000s for Sesame). The Mechanized Rain-fed Agriculture (MRA) area of Sorghum and Sesame in the Gadarif State had been increased from 1,058,241 ha to 2,799,655 ha during 1961 to 2013. Thus, we ultimately suggest that in the Gadarif State, policy makers must strive for an increase in yield per unit area by using sufficient fertilizers along with the gradual increment in tendencies of grain production through expansion of the cultivated area. 展开更多
关键词 CLIMATE CHANGE Land use policy CHANGE Food Security Gadarif STATE
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One Health:governance and regulatory framework for antimicrobial use in Malawi
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作者 Amos Lucky Mhone Dishon M.Muloi Arshnee Moodley 《Science in One Health》 2025年第1期247-254,共8页
Background:Antimicrobial resistance(AMR)poses a global threat to both human and animal health,associated with widespread use of antimicrobials across sectors.In low-and middle-income countries(LMICs)such as Malawi,wea... Background:Antimicrobial resistance(AMR)poses a global threat to both human and animal health,associated with widespread use of antimicrobials across sectors.In low-and middle-income countries(LMICs)such as Malawi,weak regulatory frameworks and limited enforcement capacity contribute to inappropriate use of antibiotics.This study examined the governance and regulatory frameworks for antimicrobial use(AMU)in Malawi's agricultural sector,identified regulatory gaps,and offers recommendations to antimicrobial stewardship.Methods:A qualitative approach was used,combining a review of policy and legal documents with semi-structured stakeholder interviews.Relevant policies and laws were sourced from government databases,the Food and Agricultural Organisation of the United Nations'(FAO)FAOLEX and AMR-LEX databases,and other publicly available resources.The FAO's legal assessment methodology was used to evaluate the policy landscape across nine key thematic areas:(1)veterinary medicinal products,(2)animal health and production practices to prevent animal diseases in terrestrial and aquatic animals,(3)feed registration,(4)pesticides,(5)food safety,(6)environment,soil and waste,(7)water quality,(8)plant health,and(9)institutional coordination.Stakeholder interviews with representatives from relevant government ministries and regulatory bodies validated findings from the document review and provided additional insight into governance challenges.A One Health governance mapping exercise was conducted to identify key institutional actors,assess their role in AMR/AMU governance,and evaluate inter-institutional relationships using social network analysis.Results:The analysis identified 522 policies relevant to AMU in agriculture,with most addressing aquatic animal health(11.3%,n=59),food safety(10.9%,n=57)and animal feed(10.9%,n=57).Several critical regulatory gaps were identified,including the absence of a legal definition for“antimicrobials,”a national essential veterinary medicines list,and standardized veterinary treatment guidelines.Additionally,there are no restrictions on the use of critically important antimicrobials for human health in veterinary settings,minimal oversight of antimicrobial-medicated feed,and no established protocols for on-farm antimicrobial disposal.Stakeholder mapping revealed limited knowledge sharing among institutions and a dependence on international donors for AMR/AMU-related activities,raising concerns about the sustainability of current initiatives.Malawi also lacks an integrated AMR and AMU monitoring system,a national prioritised AMR research agenda,and clear targets for reducing AMU in animals.Conclusion:To address these gaps,we recommend that Malawi:(1)establish a comprehensive AMR and AMU monitoring program,(2)update existing regulations to provide clear definitions and classification of veterinary antimicrobials,(3)develop and implement national veterinary treatment guidelines,(4)restrict non-therapeutic AMU,(5)enhance regulatory oversight of medicated feed,(6)strengthen One Health coordination mechanisms,(7)promote stakeholder collaboration,and(8)secure sustainable,nationally driven funding.Implemention of these measures will enhance antimicrobial stewardship,reduce AMU,mitigate the spread of AMR,and support the long-term sustainability of agricultural production in Malawi. 展开更多
关键词 Antimicrobial use Regulatory framework GAPS GOVERNANCE policy
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Papaya(Carica papaya)leaf smoking in Nigeria:A closer look at a newly recognised substance use
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作者 Gareth Davey 《Asian Pacific Journal of Tropical Medicine》 2025年第1期47-48,共2页
I applaud Adekeye AP and the journal for publishing‘Smoking of Carica papaya in Nigeria:The rationale,the public health effects and policies for intervention’.It is important to draw attention to newly recognised us... I applaud Adekeye AP and the journal for publishing‘Smoking of Carica papaya in Nigeria:The rationale,the public health effects and policies for intervention’.It is important to draw attention to newly recognised uses of substances which might alter perception,mood,and/or behaviour. 展开更多
关键词 intervention policies public health effects newly recognised uses substances carica papaya newly recognized substance use papaya leaf smoking
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自适应与多目标优化的VSG低频振荡TD3 控制策略
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作者 李永刚 周鹤然 +1 位作者 周一辰 魏凡超 《辽宁工程技术大学学报(自然科学版)》 北大核心 2026年第1期98-106,共9页
针对虚拟同步机(VSG)接入弱电网频发的低频振荡问题,提出一种融合动态惯量-阻尼协同调节与多模态双延迟深度确定性策略梯度算法的VSG智能控制方法。构建包含动态惯性-阻尼调节机制的增强型VSG模型,基于频率波动标准差与变化率的实时监测... 针对虚拟同步机(VSG)接入弱电网频发的低频振荡问题,提出一种融合动态惯量-阻尼协同调节与多模态双延迟深度确定性策略梯度算法的VSG智能控制方法。构建包含动态惯性-阻尼调节机制的增强型VSG模型,基于频率波动标准差与变化率的实时监测,设计参数连续自适应算法,实现惯量常数H和阻尼系数D的动态协同优化。设计深度前馈神经网络的振荡感知型定性策略梯度算法(TD3),采用双状态经验回放缓冲区结构,将低频振荡特征向量嵌入训练样本,并构建包含频率偏差惩罚、电压偏移抑制和振荡能量约束的多目标奖励函数。仿真和实际算例结果表明,该策略可实现VSG低频振荡的在线快速准确评估,增强系统阻尼与惯量,减少低频振荡风险,改善系统的稳定性。 展开更多
关键词 虚拟同步机 低频振荡抑制 阻尼系数 动态惯量调节 双延迟深度确定性策略梯度算法
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中国区域金融稳定的时空演进动态与“双支柱”政策调控效应
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作者 邓创 杨晨龙 谢敬轩 《中央财经大学学报》 北大核心 2026年第2期5-21,共17页
党的二十届四中全会明确指出“要增强区域发展协调性,促进区域联动发展”。区域金融稳定作为金融支持区域协调发展的重要基础,事关民生福祉与宏观稳定。本文运用MF-DFM模型实现了对31个省份区域金融稳定指数的混频测度,并在通过Dagum基... 党的二十届四中全会明确指出“要增强区域发展协调性,促进区域联动发展”。区域金融稳定作为金融支持区域协调发展的重要基础,事关民生福祉与宏观稳定。本文运用MF-DFM模型实现了对31个省份区域金融稳定指数的混频测度,并在通过Dagum基尼系数分解方法刻画其区域异质性特征、通过面板马尔科夫区制转移模型和Moran指数捕捉其时空演进动态的基础上,构建PVAR模型进一步实证检验了“双支柱”政策对区域金融稳定的调控效果。研究发现:中国区域金融稳定具有显著的空间分异特征与跨区制转移黏性,而区域间差异与交叉重叠效应是演化差异的主要来源。此外,价格型货币政策与宏观审慎政策搭配的政策组合能够有效维护区域金融稳定,并且该组合对东部地区的协同调控效果相对更为显著。本文研究或可为切实维护区域金融稳定,推动跨域金融协同治理提供有益的政策启示。 展开更多
关键词 区域金融稳定 混频动态因子模型 区域异质性 “双支柱”政策
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基于知识嵌入型深度强化学习的电力系统频率紧急控制方法
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作者 李佳旭 吴俊勇 +2 位作者 史法顺 张振远 李栌苏 《电力系统自动化》 北大核心 2026年第1期97-107,共11页
随着新型电力系统建设的快速推进,电力系统频率安全面临的挑战愈发严峻,当系统发生故障导致频率失稳时,采取紧急控制恢复频率稳定至关重要。文中提出一种基于知识嵌入型深度强化学习(DRL)的电力系统频率紧急控制方法。首先,将频率紧急... 随着新型电力系统建设的快速推进,电力系统频率安全面临的挑战愈发严峻,当系统发生故障导致频率失稳时,采取紧急控制恢复频率稳定至关重要。文中提出一种基于知识嵌入型深度强化学习(DRL)的电力系统频率紧急控制方法。首先,将频率紧急控制问题转化为马尔可夫模型,以仿真系统为强化学习环境,并基于深度确定性策略梯度(DDPG)算法构建深度强化学习智能体。此外,通过理论知识引导动作空间优化,综合考虑高频切机与低频减载两类场景。最后,在IEEE 39节点系统中进行控制效果测试,结果表明:深度强化学习智能体能够给出有效的频率紧急控制策略,维护系统频率安全;知识嵌入的方法改善了模型的训练稳定性,能显著提高智能体的策略学习效率与决策质量。 展开更多
关键词 人工智能 新型电力系统 频率安全 频率紧急控制 深度强化学习 深度确定性策略梯度 高频切机 低频减载
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Urban Spatial Restructuring in Transitional Economy——Changing Land Use Pattern in Shanghai 被引量:10
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作者 XU Jiangang LIAO Banggu +2 位作者 SHEN Qing ZHANG Feng MEI Anxin 《Chinese Geographical Science》 SCIE CSCD 2007年第1期19-27,共9页
For almost three decades, China has been undergoing significant transition from a planned economy to a market economy. Fast-paced economic growth and urbanization, interacting with market-oriented reforms in land re- ... For almost three decades, China has been undergoing significant transition from a planned economy to a market economy. Fast-paced economic growth and urbanization, interacting with market-oriented reforms in land re- sources allocation, have caused profound spatial restructuring of Chinese cities. This paper examines urban expansion and land use reconfiguration in Shanghai’s central city from 1979 to 2002, with a special focus on the effect of the adoption of the land-leasing system in 1988. The empirical research, which employs GIS-based spatial analysis tech- niques to explore land use data for multiple years, indicates fundamental changes in the spatial characteristics of urban development in Shanghai after this important land policy reform. 展开更多
关键词 land use pattern land policy GIS SHANGHAI China
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Land Use Change and Anthropogenic Driving Forces:A Case Study in Yanhe River Basin 被引量:18
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作者 SU Changhong FU Bojie +4 位作者 LU Yihe LU Nan ZENG Yuan HE Anna Halina LAMPARSKI 《Chinese Geographical Science》 SCIE CSCD 2011年第5期587-599,共13页
Human activities alter land use patterns and affect landscape sustainability. It is therefore very important to investigate the relationship between land use change and human activities. This study focuses on the dete... Human activities alter land use patterns and affect landscape sustainability. It is therefore very important to investigate the relationship between land use change and human activities. This study focuses on the detection of changing land use patterns in the Yanhe River Basin in northern Loess Plateau of China between 1995 and 2008. Landscape metrics were used to analyze the changing land use patterns and to explore the related anthropogenic driving forces. Results show that:1) Totally, 186 590 ha of croplands were converted into alternate land-use types (equivalent to 61.7% of the original cropland area). The majority of cropland areas were found to be converted into grassland and woodland areas (accounting for 55.9% and 4.9% respectively of the original cropland areas). 2) Both cropland and woodland demonstrated an increasing fragmentation tendency while grasslands showed a decreasing fragmentation tendency. 3) Multiple driving forces of land use change were thought to act together to changes in landscape metrics in the Yanhe River Basin. The anthropogenic driving forces were analyzed from four perspectives:ecological conservation policy, labor force transfer, industrial development, and rural settlement. The policy of the GfG (Grain for Green) project was the main driving factor which expedited the conversion from cropland to woodland and grassland. Industrial development was also found to affect land use change through the direct impact of economic activities such as oil exploration and agricultural production, or through indirect impacts such as the industrial structures readjustment. Labor force transfer from rural to urban areas was found to follow the industrial structure readjustment and further drove land use change from cropland to off-farm land use. Establishment of new tile-roofed houses instead of cave-type dwellings in rural settlements has helped to aggregate the original scattered land-use type of construction. 展开更多
关键词 land use landscape metrics anthropogenic driving force Grain for Green (GfG) policy Yanhe River Basin
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Land Use Changes of an Aeolian-Loessial Soil Area in Northwest China: Implications for Ecological Restoration 被引量:6
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作者 CHEN Yu-Fu LIU Yan-Sui +2 位作者 WANG Jing YAN Jian-Ping GUO Xu-Dong 《Pedosphere》 SCIE CAS CSCD 2009年第3期356-361,共6页
China has experienced dramatic land use changes over recent decades, with marked environmental and socio-economic consequences. Hengshan County, located in the aeolian-loessial area of Northwest China, was investigate... China has experienced dramatic land use changes over recent decades, with marked environmental and socio-economic consequences. Hengshan County, located in the aeolian-loessial area of Northwest China, was investigated to illustrate land use changes and their implications for environmental and long-term rural economic development. The farmland in Hengshan County significantly decreased during 1990–2003, whereas forest land and grassland increased. The conversion rates of farmland, orchard land, forest land and construction land varied markedly among different periods: 1990–1995, 1995–2000 and 2000–2003. Conversion of orchard land, grassland and construction land was dominant in 1990–1995, whereas the conversion of farmland to forest land mainly occurred in 2000–2003. The results suggested a profound transition in institutional policy and political economy of land management, including implementation of integrated soil erosion control projects, adoption of a market-oriented economy and the ‘Grain-for-Green’ policy, during this period in China. To achieve long-term sustainable land use in Hengshan County, efforts should aim at increasing off-farm income of rural families as well as establishing land-economizing mechanisms to promote land productivity, in addition to conservation measures. 展开更多
关键词 Hengshan County land management per capita land area policy sustainable land use
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Using irrigation intervals to optimize water-use efficiency and maize yield in Xinjiang,northwest China 被引量:8
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作者 Guoqiang Zhang Dongping Shen +10 位作者 Bo Ming Ruizhi Xie Xiuliang Jin Chaowei Liu Peng Hou Jun Xue Jianglu Chen Wanxu Zhang Wanmao Liu Keru Wang Shaokun Li 《The Crop Journal》 SCIE CAS CSCD 2019年第3期322-334,共13页
Worldwide, scarce water resources and substantial food demands require efficient water use and high yield.This study investigated whether irrigation frequency can be used to adjust soil moisture to increase grain yiel... Worldwide, scarce water resources and substantial food demands require efficient water use and high yield.This study investigated whether irrigation frequency can be used to adjust soil moisture to increase grain yield and water use efficiency(WUE) of high-yield maize under conditions of mulching and drip irrigation.A field experiment was conducted using three irrigation intervals in 2016: 6, 9, and 12 days(labeled D6, D9, and D12) and five irrigation intervals in 2017: 3, 6, 9, 12, and 15 days(D3, D6, D9, D12, and D15).In Xinjiang, an optimal irrigation quota is 540 mm for high-yield maize.The D3, D6, D9, D12, and D15 irrigation intervals gave grain yields of 19.7, 19.1–21.0, 18.8–20.0, 18.2–19.2, and 17.2 Mg ha^-1 and a WUE of 2.48, 2.53–2.80, 2.47–2.63, 2.34–2.45, and 2.08 kg m-3, respectively.Treatment D6 led to the highest soil water storage, but evapotranspiration and soil-water evaporation were lower than other treatments.These results show that irrigation interval D6 can help maintain a favorable soil-moisture environment in the upper-60-cm soil layer, reduce soilwater evaporation and evapotranspiration, and produce the highest yield and WUE.In this arid region and in other regions with similar soil and climate conditions, a similar irrigation interval would thus be beneficial for adjusting soil moisture to increase maize yield and WUE under conditions of mulching and drip irrigation. 展开更多
关键词 Irrigation frequency Soil moisture MAIZE High yield(>15 Mg ha^(-1)) Water use efficiency
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The impacts of national essential medicine policies on the rational use of medicines in China: A cross-sectional study in primary health care institution 被引量:3
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作者 Xinpu Lu Zhigang Guo +3 位作者 Mengyuan Fu Haishaerjiang Wushouer Luwen Shi Xiaodong Guan 《Journal of Chinese Pharmaceutical Sciences》 CAS CSCD 2019年第1期49-55,共7页
Irrational use of medicines is a major problem worldwide, and it is believed there would be positive correlation between the National Essential Medicines Policies(NEMPs) and the level of rational use of medicines(RUMs... Irrational use of medicines is a major problem worldwide, and it is believed there would be positive correlation between the National Essential Medicines Policies(NEMPs) and the level of rational use of medicines(RUMs). Though there is some early evidence on the NEMPs’ effects on RUMs in China, the evidence is scarce, and conclusions vary. In the present study, we aimed to evaluate the impacts of the NEMPs of China on the RUMs in the primary health care institutions(PHCs). A cross-sectional survey was conducted in 2010. A total of 201 PHCs from six provinces of China were selected, and 39 181 prescriptions were extracted from January to June, 2010. Six indicators were used and tested by independent-samples T test. We found that the average number of drugs per prescription in PHCs with NEMP implementation(the treatment group) was significantly higher than that of the group without NEMP implementation(the control group)(3.37 vs. 2.83, P<0.01). There was no significant difference in the average cost per prescription(81.43 vs. 75.02). The percentage of prescriptions, including an antibiotic(53.40% vs. 36.48%, P<0.01) or an injection(40.54% vs. 27.94%, P<0.01), was higher in the treatment group, and the percentage of drugs prescribed by general name was significantly lower(83.71% vs. 93.11%, P<0.01). For the percentage of drugs prescribed from essential medicines list, the treatment group exhibited the higher ratio(76.12% vs. 53.45%, P<0.01). From this study, the NEMPs were not likely to have a positive impact on RUMs. China still needed efforts to improve the selection, the absence of physicians’ active involvement, and the patients’ habits of irrational medication use. 展开更多
关键词 Rational use of medicines Primary health care institutions National Essential Medicines Policies Health care reforms
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Forests of Greece, Their Multiple Functions and Uses, Sustainable Management and Biodiversity Conservation in the Face of Climate Change 被引量:1
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作者 Konstantinos A. Spanos Asimina Skouteri +6 位作者 Dionysios Gaitanis Panos V. Petrakis Ioannis Meliadis Panagiotis Michopoulos Alexandra Solomou Panagiotis Koulelis Evangelia V. Avramidou 《Open Journal of Ecology》 2021年第4期374-406,共33页
This is a review paper based on national and international literature, national inventories and empirical approach. A general overview of the forests, forest management and forest biodiversity of Greece are briefly su... This is a review paper based on national and international literature, national inventories and empirical approach. A general overview of the forests, forest management and forest biodiversity of Greece are briefly summarized. The distribution of the main forest species and their ecosystems in the Geographic regions of Greece is presented in a tabular form. Their multiple functions and uses, their management type/regime, their risks and threats, protection and conservation measures are also synoptically described. Furthermore, adaptive forest management and silviculture as well as management of genetic diversity in order to face climate change are also analysed. Research priority areas on biodiversity and challenges for biodiversity research and related policy in Greece have been summarized. The new Rural Development Program (2014-2020), which is currently in the final phase of implementation, will take into consideration the forest itself and forest-related European and National legal obligations. Finally, major conclusions and research priority areas on future management and conservation of forests are highlighted. 展开更多
关键词 Greece FORESTS Multiple uses Management BIODIVERSITY CONSERVATION Forest policy Climate Change Strategic Targets
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Optimal Operation of Multipurpose Reservoir for Irrigation Planning with Conjunctive Use of Surface and Groundwater
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作者 N. G. Nikam D. G. Regulwar 《Journal of Water Resource and Protection》 2015年第8期636-646,共11页
In the present study, a Linear Programming (LP) model is developed for the conjunctive use of surface water and ground water to obtain the optimal operating policy for a multipurpose single reservoir. The objective of... In the present study, a Linear Programming (LP) model is developed for the conjunctive use of surface water and ground water to obtain the optimal operating policy for a multipurpose single reservoir. The objective of the present study is to maximize the net benefit from the command area under consideration. The constraints imposed on the objective function are maximum and minimum irrigation demands, reservoir storages and canal capacity. The model takes into account the continuity constraint which includes inflows in to the reservoir, releases for irrigation, releases for hydro-power generation, evaporation losses, feeder canal releases, initial and final storages in the reservoir in each time period. The developed model is applied to the case study of Jayakwadi reservoir stage-I, built across river Godavari, Maharashtra, India. Initially the model is solved for the availability of surface water which results in net benefit of 3373.45 million rupees with irrigation intensity is 57.07%. Next the model solved by considering the availability of surface water and available potential of groundwater in the area, which results in net benefits of 3590.02 million rupees with an intensity of irrigation 58.48%. The present model takes in to account the socio-economic requirement of growing the essential crops to meet the requirement of the society. The model has also generated the canal wise optimal releases for irrigation and power, monthly utilization of groundwater, storages in the reservoir at the end of every month and corresponding head over the turbine. 展开更多
关键词 RESERVOIR Operation OPTIMAL policy Conjunctive use GROUNDWATER IRRIGATION PLANNING
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