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Alleviating the anisotropic microstructural change and boosting the lithium ions diffusion by grain orientation regulation for Ni-rich cathode materials
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作者 Xinyou He Shilin Su +3 位作者 Bao Zhang Zhiming Xiao Zibo Zhang Xing Ou 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第1期213-222,I0005,共11页
Generally,layered Ni-rich cathode materials exhibit the morphology of polycrystalline secondary sphere composed of numerous primary particles.While the arrangement of primary particles plays a very important role in t... Generally,layered Ni-rich cathode materials exhibit the morphology of polycrystalline secondary sphere composed of numerous primary particles.While the arrangement of primary particles plays a very important role in the properties of Ni-rich cathodes.The disordered particle arrangement is harmful to the cyclic performance and structural stability,yet the fundamental understanding of disordered structure on the structural degradation behavior is unclarified.Herein,we have designed three kinds of LiNi_(0.83)Co_(0.06)Mn_(0.11)O_(2) cathode materials with different primary particle orientations by regulating the precursor coprecipitation process.Combining finite element simulation and in-situ characterization,the Li^(+)transport and structure evolution behaviors of different materials are unraveled.Specifically,the smooth Li^(+)diffusion minimizes the reaction heterogeneity,homogenizes the phase transition within grains,and mitigates the anisotropic microstructural change,thereby modulating the crack evolution behavior.Meanwhile,the optimized structure evolution ensures radial tight junctions of the primary particles,enabling enhanced Li^(+)diffusion during dynamic processes.Closed-loop bidirectional enhancement mechanism becomes critical for grain orientation regulation to stabilize the cyclic performance.This precursor engineering with particle orientation regulation provides the useful guidance for the structural design and feature enhancement of Ni-rich layered cathodes. 展开更多
关键词 Ni-rich cathode grain orientation regulation Anisotropic microstructural change Precursor engineering Li~+-ions diffusion
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Quantifying major sources of uncertainty in projecting the impact of climate change on wheat grain yield in dryland environments
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作者 Reza DEIHIMFARD Sajjad RAHIMI-MOGHADDAM +1 位作者 Farshid JAVANSHIR Alireza PAZOKI 《Journal of Arid Land》 SCIE CSCD 2023年第5期545-561,共17页
Modelling the impact of climate change on cropping systems is crucial to support policy-making for farmers and stakeholders.Nevertheless,there exists inherent uncertainty in such cases.General Circulation Models(GCMs)... Modelling the impact of climate change on cropping systems is crucial to support policy-making for farmers and stakeholders.Nevertheless,there exists inherent uncertainty in such cases.General Circulation Models(GCMs)and future climate change scenarios(different Representative Concentration Pathways(RCPs)in different future time periods)are among the major sources of uncertainty in projecting the impact of climate change on crop grain yield.This study quantified the different sources of uncertainty associated with future climate change impact on wheat grain yield in dryland environments(Shiraz,Hamedan,Sanandaj,Kermanshah and Khorramabad)in eastern and southern Iran.These five representative locations can be categorized into three climate classes:arid cold(Shiraz),semi-arid cold(Hamedan and Sanandaj)and semi-arid cool(Kermanshah and Khorramabad).Accordingly,the downscaled daily outputs of 29 GCMs under two RCPs(RCP4.5 and RCP8.5)in the near future(2030s),middle future(2050s)and far future(2080s)were used as inputs for the Agricultural Production Systems sIMulator(APSIM)-wheat model.Analysis of variance(ANOVA)was employed to quantify the sources of uncertainty in projecting the impact of climate change on wheat grain yield.Years from 1980 to 2009 were regarded as the baseline period.The projection results indicated that wheat grain yield was expected to increase by 12.30%,17.10%,and 17.70%in the near future(2030s),middle future(2050s)and far future(2080s),respectively.The increases differed under different RCPs in different future time periods,ranging from 11.70%(under RCP4.5 in the 2030s)to 20.20%(under RCP8.5 in the 2080s)by averaging all GCMs and locations,implying that future wheat grain yield depended largely upon the rising CO2 concentrations.ANOVA results revealed that more than 97.22% of the variance in future wheat grain yield was explained by locations,followed by scenarios,GCMs,and their interactions.Specifically,at the semi-arid climate locations(Hamedan,Sanandaj,Kermanshah and Khorramabad),most of the variations arose from the scenarios(77.25%),while at the arid climate location(Shiraz),GCMs(54.00%)accounted for the greatest variation.Overall,the ensemble use of a wide range of GCMs should be given priority to narrow the uncertainty when projecting wheat grain yield under changing climate conditions,particularly in dryland environments characterized by large fluctuations in rainfall and temperature.Moreover,the current research suggested some GCMs(e.g.,the IPSL-CM5B-LR,CCSM4,and BNU-ESM)that made moderate effects in projecting the impact of climate change on wheat grain yield to be used to project future climate conditions in similar environments worldwide. 展开更多
关键词 wheat grain yield climate change Agricultural Production Systems sIMulator(APSIM)-wheat model General Circulation Models(GCMs) arid climate semi-arid climate Iran
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Effect of Supplementary Irrigation on the Yield of Sorghum (Sorghum bicolor L. Moench) in the Context of Climate Change in the Dry Savannahs of Togo
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作者 Adjiwanou Atiglo-Gbenou Yaovi Ouézou Azouma Jean Mianikpo Sogbedji 《American Journal of Climate Change》 2024年第2期163-174,共12页
Under the current context of climate change, supplementary irrigation may be needed for crop production resilience. We determined the effects of supplementary irrigation on sorghum grain yield in the dry Savannah regi... Under the current context of climate change, supplementary irrigation may be needed for crop production resilience. We determined the effects of supplementary irrigation on sorghum grain yield in the dry Savannah region of Togo. A two-year trial was conducted in a controlled environment at AREJ, an agro-ecological center in Cinkassé. The plant material was sorghum variety Sorvato 28. The experimental design was a Completely Randomized Block with three replications and three treatments as follows: T0 control plot (rainfed conditions);T1 (supplementary irrigation from flowering to grain filling stage) and T2 (supplementary irrigation from planting to grain filling stage). Two irrigation techniques (furrow and Californian system) were used under each watering treatment. The results showed that irrigation technique significantly affected panicle length with no effect on 1000 grains mass. Panicle length and grain yields varied from 15.59 to 25.71 cm and 0.0 to 2.06 t∙h−1, respectively, with the highest values (25.66 cm and 2.06 t∙h−1, respectively) under the T2 treatment with the California system-based supplementary irrigation. The comparison of results obtained on treatment T0 and T2, shows that supplementary irrigation increased the yields by at least 68.62%. Supplementary irrigation during sowing and growing season (T2) improved sorghum yields in the dry savannahs of Togo, with a better performance of the California irrigation system. 展开更多
关键词 Climate change Supplementary Irrigation Sorghum grain Yield Dry Savannah TOGO
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Policy Suggestions for the Slowdown in Per Capital Output of Grain Growth in China
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作者 Yang Yang 《Meteorological and Environmental Research》 CAS 2013年第10期48-51,共4页
China is a large agricultural and the most populous country, so it is a crucial importance for the food security. The basic situation of food in our country is self-sufficiency, a certain amount of imports and reserve... China is a large agricultural and the most populous country, so it is a crucial importance for the food security. The basic situation of food in our country is self-sufficiency, a certain amount of imports and reserves. The output of grain in our country has increased annually, however, as a result of policy adjustments and other factors like environmental pollution, together with a large population base and the trend of excessively popu- lous growth, the growth of grain output is relatively slow, which will be harmful for our grain security as well as the healthy development of the na- tional economy. In this case, several solutions could be tried, such as improving the level of science and technology, adjusting industrial policies and controlling environmental pollution. Besides, we ought to strongly advocate thrifty behavior to increase income and reduce expenditure. 展开更多
关键词 per capita output of grain SLOWDOWN Policy suggestions China
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Spatiotemporal characteristics and driving mechanisms of land use/land cover(LULC)changes in the Jinghe River Basin,China
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作者 WANG Yinping JIANG Rengui +4 位作者 YANG Mingxiang XIE Jiancang ZHAO Yong LI Fawen LU Xixi 《Journal of Arid Land》 SCIE CSCD 2024年第1期91-109,共19页
Understanding the trajectories and driving mechanisms behind land use/land cover(LULC)changes is essential for effective watershed planning and management.This study quantified the net change,exchange,total change,and... Understanding the trajectories and driving mechanisms behind land use/land cover(LULC)changes is essential for effective watershed planning and management.This study quantified the net change,exchange,total change,and transfer rate of LULC in the Jinghe River Basin(JRB),China using LULC data from 2000 to 2020.Through trajectory analysis,knowledge maps,chord diagrams,and standard deviation ellipse method,we examined the spatiotemporal characteristics of LULC changes.We further established an index system encompassing natural factors(digital elevation model(DEM),slope,aspect,and curvature),socio-economic factors(gross domestic product(GDP)and population),and accessibility factors(distance from railways,distance from highways,distance from water,and distance from residents)to investigate the driving mechanisms of LULC changes using factor detector and interaction detector in the geographical detector(Geodetector).The key findings indicate that from 2000 to 2020,the JRB experienced significant LULC changes,particularly for farmland,forest,and grassland.During the study period,LULC change trajectories were categorized into stable,early-stage,late-stage,repeated,and continuous change types.Besides the stable change type,the late-stage change type predominated the LULC change trajectories,comprising 83.31% of the total change area.The period 2010-2020 witnessed more active LULC changes compared to the period 2000-2010.The LULC changes exhibited a discrete spatial expansion trend during 2000-2020,predominantly extending from southeast to northwest of the JRB.Influential driving factors on LULC changes included slope,GDP,and distance from highways.The interaction detection results imply either bilinear or nonlinear enhancement for any two driving factors impacting the LULC changes from 2000 to 2020.This comprehensive understanding of the spatiotemporal characteristics and driving mechanisms of LULC changes offers valuable insights for the planning and sustainable management of LULC in the JRB. 展开更多
关键词 land use/land cover(LULC)changes driving mechanisms trajectory analysis geographical detector(Geodetector) grain for Green Project Jinghe River Basin
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Dynamic Changes in Per Capita Net Income of Rural Residents in Nyingchi City of Tibet
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作者 Luobu Dunzhu Weilian ZENG 《Asian Agricultural Research》 2017年第3期20-23,共4页
Through an in-depth analysis of the per capita net income of rural residents in Nyingchi City,it was known that the per capita net income of rural residents in Nyingchi City was increasing at high speed in recent 10 y... Through an in-depth analysis of the per capita net income of rural residents in Nyingchi City,it was known that the per capita net income of rural residents in Nyingchi City was increasing at high speed in recent 10 years. However,the wage income,household operating income,and agricultural income gap constitute the major factors influencing the gap of the per capita net income of rural residents in Nyingchi City. Finally,it came up with recommendations including promoting the reasonable flow of labor to the secondary and tertiary industries,increasing the wage income and transfer income of rural residents,accelerating the construction of small towns in rural areas,promoting the development of rural cooperatives,implementing the strategy of " benefiting farmers and strengthening tourism",promoting integration of agriculture and eco-tourism,promoting the development of modern agriculture,and expanding diversified production income of farmers. 展开更多
关键词 Dynamic changes per capita net income of rural residents Nyingchi City of Tibet
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Climate Change, Risk and Grain Yields in China 被引量:15
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作者 Rainer Holst Xiaohua Yu Carola Grün 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2013年第7期1279-1291,共13页
Adopting Just and Pope (1978, 1979) style yield functions, this paper proposes a method to analyze the impacts of regional climate change on grain production in China. We find that changes in climate will affect gra... Adopting Just and Pope (1978, 1979) style yield functions, this paper proposes a method to analyze the impacts of regional climate change on grain production in China. We find that changes in climate will affect grain production in North and South China differently. Specifically, it emerges that a 1℃ increase in annual average temperature could reduce national grain output by 1.45% (1.74% reduction in North China and 1.19% reduction in South China), while an increase in total annual precipitation of around 100 mm could increase national grain output by 1.31% (3.0% increase in North China and 0.59% reduction in South China). 展开更多
关键词 grain yield climate change yield risk China
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Biochemical Changes Associated with Germinating Rice Grains and Germination Improvement 被引量:15
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作者 Subajiny VELUPPILLAI Ketheeswary NITHYANANTHARAJAH +2 位作者 Seevaratnam VASANTHARUBA Sandrasegarampillai BALAKUMAR Vasanthy ARASARATNAM 《Rice science》 SCIE 2009年第3期240-242,共3页
To determine biochemical changes during the germination of rice grains (Oryza sativa L. subsp, indica var. Mottaikaruppan) and to improve germination rate using gibberellic acid and surfactants [sodium dodecyl sulfa... To determine biochemical changes during the germination of rice grains (Oryza sativa L. subsp, indica var. Mottaikaruppan) and to improve germination rate using gibberellic acid and surfactants [sodium dodecyl sulfate (SDS) (1.0 g/L) and Triton-X-100 (1.0 mL/L)], whole rice grains soaked in distilled water for 12 h at 30℃were germinated in the dark at 30℃ for five days. The highest germination rate (77.1%) was obtained on the 5th day. An increase in the content of reducing sugars from 7.3 to 58.1 mg/g DM (dry matter) was observed from the 1st day of germination. Free amino acids and soluble protein contents increased to 3.69 and 5.29 mg/g DM, respectively on the 5^th day of germination. Total protein content decreased from 100.5 to 91.0 g/kg DM during germination. Increases in amylolytic (1.1 to 190.0 U/g DM) and proteolytic (0 to 0.12 U/g DM) activities were observed during germination. Effects of different concentrations of gibberellic acid on the germination of rice grains were evaluated and 0.1 g/L was found to promote germination. When effects of gibberellic acid (0.1 g/L) and surfactants were evaluated individually and together, higher germination rate was observed in the control experiment (grains germinated in distilled water), whereas giberellic acid and surfactants decreased the germination rate. Therefore, the flour obtained from the grains germinated for four days using distilled water to obtain high content of soluble materials and enzyme activities can be used in preparation of bakery items. 展开更多
关键词 GERMINATION whole rice grains biochemical changes amylase activity protease activity
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Do farmers care about climate change? Evidence from five major grain producing areas of China 被引量:6
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作者 SONG Chun-xiao LIU Rui-feng +1 位作者 Les Oxley MA Heng-yun 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2019年第6期1402-1414,共13页
Using a logistic model,this paper empirically investigated farmers’perception of climate change and its determinants based on a field survey of 1 350 rural households across five major grain producing provinces in Ch... Using a logistic model,this paper empirically investigated farmers’perception of climate change and its determinants based on a field survey of 1 350 rural households across five major grain producing provinces in China.The results show:i)There is an apparent difference in perception levels for long-term temperature and precipitation changes.Specifically,57.4%of farmers perceived the long-term temperature change correctly,but only 29.7%of farmers perceived the long-term precipitation change correctly;ii)The factors influencing the farmers’perceptions are almost completely different between precipitation and temperature,the former are mostly agriculture related,while latter are mostly non-agriculture related,except for farm size;and iii)Farmers are not expected to pay more attention to long-term precipitation changes over the crop growing seasons,because less than 30%of farmers can correctly perceive long-term precipitation change.Therefore,to improve the accuracy of farmers’perceptions of climate change,the government is recommended to:i)enhance education and training programs;ii)speed up land transfer and expand household land farm size;iii)develop farmer cooperative organizations;iv)invest more in agricultural infrastructure,specifically in major grain producing regions;and v)improve the agricultural environment and increase farming income. 展开更多
关键词 China major grain producing areas determinants CLIMATE change perCEPTION IRRIGATION areas
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China’s Potential of Grain Production Due to Changes in Agricultural Land Utilization in Recent Years 被引量:19
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作者 XIN Liangjie LI Xiubin ZHU Huiyi TAN Minghong 《Chinese Geographical Science》 SCIE CSCD 2009年第2期97-103,共7页
The changes in utilization of agricultural land have gradually grown into one of the major factors impacting grain output in China. This study explores the various components of agricultural production in China from t... The changes in utilization of agricultural land have gradually grown into one of the major factors impacting grain output in China. This study explores the various components of agricultural production in China from the land utilization perspective, involving changes in grain production per unit area, multi-cropping index, and adjustment of agricultural structure. Compared with the record values, different research methodologies are used to analyze the po- tential of above three components. The results indicate that grain production potential of 65.68×109kg was unexploited in 2006, in which 45.8×109kg came from the restructuring in agriculture. So we can infer that the reduction of grain production in China could be primarily attributed to agricultural restructuring in recent years. So the productive poten- tial can be fully restored by increasing agricultural investment, or recovering agricultural structure in favorable condi- tions. So we can say that China’s current condition of food security is good. 展开更多
关键词 粮食生产潜力 农业生产 中国 土地使用 农业结构调整 组成部分 粮食产量 农用土地
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Analysis of the Changes in China's Grain Production Costs over the Past Decade 被引量:1
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作者 Shuangjin WANG Chen LIANG 《Asian Agricultural Research》 2015年第2期19-22,共4页
China's grain production cost has risen constantly since 2003. This paper starts from the grain production cost changes of unit area and unit quality,to analyze the reasons for China's grain production cost ch... China's grain production cost has risen constantly since 2003. This paper starts from the grain production cost changes of unit area and unit quality,to analyze the reasons for China's grain production cost change in the last decade. It points out that the direct cause of changes in grain production cost is the steady growth of material and services costs,the fastest growth of labor costs and fast growth of land costs. The indirect cause of grain production high cost is the low efficiency in numerous and dispersive farmer production management,obviously insufficient agricultural infrastructure construction,waste phenomenon grain in production process and low contribution rate of agricultural technology.On this basis,it is recommended to reduce China's grain production cost and improve grain production conditions. 展开更多
关键词 grain PRODUCTION changeS in COSTS The PAST decade
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Study on the Concept of Per Capita Cumulative Emissions and Allocation Options 被引量:3
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作者 Shengmin Yu Xiang Gao Cuimei Ma Lihua Zhai 《Advances in Climate Change Research》 SCIE 2011年第2期79-85,共7页
全球长期的排放减小目标为温室气体排出物的公平分配需要明确的选择。从开发国家的学者提出了公平人均的累积排放权利的概念。有四个可能的运作的定义,源于这个概念。为排放权利的分配的这些潜在的选择与数学方程被表示。通过简单模拟... 全球长期的排放减小目标为温室气体排出物的公平分配需要明确的选择。从开发国家的学者提出了公平人均的累积排放权利的概念。有四个可能的运作的定义,源于这个概念。为排放权利的分配的这些潜在的选择与数学方程被表示。通过简单模拟,这份报纸揭示每种选择的优点,劣势和特征。引证于, S. , C. 妈 X. 高,等, 2011:在人均的累积排出物和分配选择的概念上学习。副词。Clim。变化物件, 2 (2 ) , doi:10.3724/SP .J.1248.2011.00079。 展开更多
关键词 温室气体排放 公平分配 选项 累积 发展中国家 方程表示 分配方案 排放权
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Fine-grained permutation entropy as a measure of natural complexity for time series 被引量:2
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作者 刘小峰 王越 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第7期2690-2695,共6页
In a recent paper [2002 Phys. Rev. Lett. 88 174102], Bandt and Pompe propose permutation entropy (PE) as a natural complexity measure for arbitrary time series which may be stationary or nonstationary,deterministic ... In a recent paper [2002 Phys. Rev. Lett. 88 174102], Bandt and Pompe propose permutation entropy (PE) as a natural complexity measure for arbitrary time series which may be stationary or nonstationary,deterministic or stochastic.Their method is based on a comparison of neighbouring values.This paper further develops PE,and proposes the concept of fine-grained PE (FGPE) defined by the order pattern and magnitude of the difference between neighbouring values. This measure excludes the case where vectors with a distinct appearance are mistakenly mapped onto the same permutation type,and consequently FGPE becomes more sensitive to the dynamical change of time series than does PE,according to our simulation and experimental results. 展开更多
关键词 COMPLEXITY ENTROPY dynamical change fine-grained symbolization
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Metric of Carbon Equity:Carbon Gini Index Based on Historical Cumulative Emission per Capita 被引量:1
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作者 Fei Teng Jiankun He Xunzhang Pan Chi Zhang 《Advances in Climate Change Research》 SCIE 2011年第3期134-140,共7页
这份报纸与调整使用 Lorenz 曲线和 Gini 索引到人均的历史的累积排放构造碳 Gini 索引在气候变化区域测量不平等。在空气的 70% 碳空间被用于的分析表演无可比拟分发,它在世界上几乎与在有在富人和穷人之间的最大的差距的一个国家的... 这份报纸与调整使用 Lorenz 曲线和 Gini 索引到人均的历史的累积排放构造碳 Gini 索引在气候变化区域测量不平等。在空气的 70% 碳空间被用于的分析表演无可比拟分发,它在世界上几乎与在有在富人和穷人之间的最大的差距的一个国家的收入的一样。碳公平应该在气候议程是紧急和优先级。在这份报纸建立的碳 Gini 索引能被用来在碳空间的分发测量不平等并且在不同建议之中为碳公平的测量提供确定的指示物。引证 Teng, F. , J。他, X. 平底锅,等, 2011:碳公平公制:碳 Gini 索引基于历史的累积排放人均。副词。Clim。变化物件, 2 (3 ) , doi:10.3724/SP .J.1248.2011.00134。 展开更多
关键词 碳基 股权 排放 历史 公制 累积 气候变化 空间分布
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Changes in Cultivated Land Resources and Grain Potential in China's Mainland between 1996 and 2007
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作者 GUO Lina ZHANG Di ZHANG Jinke 《Journal of Landscape Research》 2014年第2期4-10,共7页
Analysis of recent changes in the amount and nature of cultivated land and grain potential, and the impacts of these changes on grain security in China's Mainland provides vital information for revising and develo... Analysis of recent changes in the amount and nature of cultivated land and grain potential, and the impacts of these changes on grain security in China's Mainland provides vital information for revising and developing strategies regarding protection of cultivated land and national grain security. This study examined changes in the area of cultivated land and in grain potential in agro-ecological zones using the "change rate" method. Agro-ecological subzones were used as the basic units and agro-ecological zones as the research units. We then studied changes for all of China's Mainland using the "gravity centre model" and analyzed the structural change of cultivated lands in each agro-ecological zone to investigate the changes in detail. The results show that both cultivated land and grain potential in China's Mainland decreased from 1996 to 2007. The structural and quantitative changes in each zone have caused the shift of the gravity centres of cultivated land and grain potential in China's Mainland to the northeast. Unfortunately, it is unlikely that natural and economic resources can keep up with this change. Although a large gap remains between the grain potential and the actual grain yield, the rapid loss of grain potential and the direction of change pose great threats to grain security. To ensure comprehensive grain security in China, it is vital to rethink the regional patterns of grain production according to natural conditions without jeopardising cultivated land protection(quantitative and qualitative), and consider the direction of cultivated land use and reconstruction according to local natural conditions, water and soil resources, and the level of economic development, and then work steadily to improve the grain potential. 展开更多
关键词 Cultivated land grain potential change China's Mainland
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Spike-Grain Structure of Winter Wheat and Its Climate Change Tendency in Jiangsu
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作者 Shang Shun Zhang Xuhui Shang Zhaotang 《Meteorological and Environmental Research》 CAS 2019年第1期70-75,80,共7页
To scientifically respond to the impact of climate change on winter wheat production,spike-grain structure data of winter wheat at Jiangsu Phenometeorological Observatory were taken as the sample. Based on agrometeoro... To scientifically respond to the impact of climate change on winter wheat production,spike-grain structure data of winter wheat at Jiangsu Phenometeorological Observatory were taken as the sample. Based on agrometeorology,statistics and GIS analytical technique,status quo of spike-grain structure of winter wheat in Jiangsu and its climate change tendency were analyzed systemically. The results showed that climate change rate( CTR) of mature spike number( NS) was between-53. 37 and 256. 51 spikes/( m^2·10 a),and mean of whole province was 21.45 spikes/( m^2·10 a). CTR of number of grains per panicle( GNPS) was between-0. 58 and 12. 52 grains/( spike·10 a),and mean of whole province was 2. 39 grains/( spike·10 a). CTR of thousand-grain weight( TSW) was between-1. 65 and 16. 39 g/( 1 000 grains·10 a),and mean of whole province was 2. 86 g/( 1 000 grains·10 a). For the means of NS,GNPS,and TSW in whole province,they all showed the increasing trend with climate change,and they were just unbalanced among regions. Climate change induced the variation of meteorological conditions during growth period of winter wheat in Jiangsu. The variation of unity yield( UY) caused by this kind of change trend only accounted for-4. 32%-17. 23% of that in normal climate years,and mean of whole province was 6. 4%. That is to say,comprehensive impact of meteorological condition was favorable for improving the yield of winter wheat with climate change. Therefore,coordination level of winter wheat growth and real-time meteorological conditions could be regulated by breeding the varieties with wide climate suitability,regulating sowing date and density according to local production and management level,rational fertilization and applying growth regulator,to mitigate the adverse effects of climate change on winter wheat production,and reach high yield and quality. 展开更多
关键词 CLIMATE change Spike-grain structure Characteristic analysis
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Cultivated-land change in Mu Us Sandy Land of China before and after the first-stage grain-for-green policy
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作者 Na Li ChangZhen Yan +1 位作者 JiaLi Xie JianXia Ma 《Research in Cold and Arid Regions》 CSCD 2018年第4期347-353,共7页
Mu Us Sandy Land(MUSL) of China, as a typical eco-fragile and farming-pastoral transitional region, shows great vulnerability to disturbances from cultivation activity. In this region, the conflict between cultivation... Mu Us Sandy Land(MUSL) of China, as a typical eco-fragile and farming-pastoral transitional region, shows great vulnerability to disturbances from cultivation activity. In this region, the conflict between cultivation activity and environmental protection has not attracted great importance until the implementation of China's Grain-for-Green Policy(CGGP) since2000. Here, using Landsat5 TM/Landsat7 ETM+ images from 1990, 2000, and 2010, we monitor the cultivation activity and land-use/cover changes(LUCC) resulting from cultivation activity in the MUSL region. Based on the data from images, we developed a series of databases of cultivated activity-induced LUCC and use them to discuss comparatively the spatio-temporal evolution trends of cultivation activity before and after CGGP implementation. These results provide evidence for managers to evaluate the implementation effectiveness of governmental policy and the influence of cultivation activity on the ecological environment of the MUSL region. 展开更多
关键词 MU Us SANDY LAND China's grain-for-green POLICY CULTIVATED LAND land-use/cover change landsat
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中国特色社会主义粮食政策变迁与政策主体协同网络演化研究--基于1953-2022年政策文本的分析
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作者 刘威 陈佳梦 钟镇 《智库理论与实践》 北大核心 2024年第3期40-52,共13页
[目的/意义]粮食政策是保障国家粮食安全的重要制度设计,研究其政策变迁历程及特征对优化中国特色社会主义粮食政策体系具有重要意义。[方法/过程]本文以1953-2022年发布的410份粮食政策为研究样本,运用新制度经济学中的制度变迁理论,... [目的/意义]粮食政策是保障国家粮食安全的重要制度设计,研究其政策变迁历程及特征对优化中国特色社会主义粮食政策体系具有重要意义。[方法/过程]本文以1953-2022年发布的410份粮食政策为研究样本,运用新制度经济学中的制度变迁理论,结合重要事件法,划分了粮食政策主题变迁的历史阶段,发现粮食政策变迁的相机组合模式。基于社会网络理论,利用政策文本计量方法,研究了粮食政策主体的协同网络演化特征。[结果/结论]研究发现:(1)我国粮食政策变迁的总体基调由“以取为主”向“以予为主”转变,调控手段由政府主导向市场引导转变,实施目标由数量安全拓展到数量质量并重;(2)粮食政策变迁呈现出由强制性变迁向诱制性变迁转变、激进式变迁与渐进式变迁交替呈现、调控手段路径依赖等鲜明特征;(3)粮食政策主体具有典型的“小世界”网络特征,协同的复杂性、协调性与全域性愈发显著;(4)“广度-强度”二维分析框架表明,政策主体协同网络先后呈现出分散型、局部集中型、“中心-边缘”型、“中心-极化”型、均衡多主体型的演化趋势,且核心主体地位趋向稳固。 展开更多
关键词 粮食政策 政策变迁 政策主体 协同网络
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基于耕地资源质量分类监测的土壤条件变化对粮食产量的影响——以河南省兰考县为例
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作者 樊鹏 王自威 +3 位作者 邵红旗 杨青伟 王磊 杨喜会 《中国农学通报》 2024年第10期83-88,共6页
为突出土壤条件变化对粮食产量的影响,采用趋势分析法和对比分析法,以兰考县耕地资源质量分类监测工作为例,分析土壤监测样点不同年份的土壤条件变化对当地粮食产量造成的影响。研究表明,土壤有机质含量的增加和土壤pH在合理范围内的增... 为突出土壤条件变化对粮食产量的影响,采用趋势分析法和对比分析法,以兰考县耕地资源质量分类监测工作为例,分析土壤监测样点不同年份的土壤条件变化对当地粮食产量造成的影响。研究表明,土壤有机质含量的增加和土壤pH在合理范围内的增加都能够提升粮食产量。建议以测土配方施肥为基础,增加有机肥的使用量,提升土壤有机质含量,并针对当地土壤的实际情况和主要作物类型,提出有针对性的改良土壤pH的措施,以提升粮食产量。 展开更多
关键词 耕地资源质量分类 监测 土壤条件 变化 粮食产量 影响
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谷物冷却机降温通风粮温变化规律实验研究 被引量:2
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作者 郑焱诚 屈登辉 +2 位作者 朱延光 刘胜强 陈戈 《中国粮油学报》 CAS CSCD 北大核心 2024年第1期33-38,共6页
科学高效使用通风设备对粮仓通风,可有效控制粮堆温度,保障粮食储藏安全。为探究谷物冷却机通风过程中的粮堆温度变化规律,采用谷物冷却机先后对2个浅圆仓、3个超高大平房仓进行冷却通风对比实验。结果表明,浅圆仓通风效果良好,温度迁... 科学高效使用通风设备对粮仓通风,可有效控制粮堆温度,保障粮食储藏安全。为探究谷物冷却机通风过程中的粮堆温度变化规律,采用谷物冷却机先后对2个浅圆仓、3个超高大平房仓进行冷却通风对比实验。结果表明,浅圆仓通风效果良好,温度迁移速率约为1.7~1.9 m/d,通风11 d后会降低整仓粮温,无通风死角;平房仓通风过程中会形成风道,打乱粮堆原始冷心,有效降低平均粮温但无法实现整仓粮温均匀降低,存在通风死角。 展开更多
关键词 通风 谷物冷却机 温度变化
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