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China’s Price System Jeopardizes its Grain Reserves
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作者 李宾 《China Economist》 2008年第5期12-25,共14页
2008 is a year of bumper harvest in summer grain across China. The failure of numerous state-owned grain depots to purchase grain in times of bumper harvest, however, directly threatens grain reserve security and stat... 2008 is a year of bumper harvest in summer grain across China. The failure of numerous state-owned grain depots to purchase grain in times of bumper harvest, however, directly threatens grain reserve security and state control over grain prices in the upcoming year. An important factor underpinning the difficulty of state grain depots to purchase grain is the unwillingness of farmers to sell grain due to the excess of the current market price over the government "protected price" aimed at preventing cheap grain from harming farmers. When grassroots grain depots find themselves in trouble, foreign capital stealthily moves in by taking advantage of this situation. To fulfill grain storage tasks and receive various state subsidies, some state-owned grain depots have no alternative but to surreptitiously raise the purchase price. By contrast, some not so courageous state-owned grain depots can only borrow money to finance the purchase of commodity grain at market prices and subsequently figure out a way to pay back such loans. Behind such distorted grain purchase behavior lies a rough and rugged history of grain price reform in China. 展开更多
关键词 China s Price system Jeopardizes its grain reserves
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Nation Needs to Reform Its Foreign Exchange Reserves Management System
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作者 李扬 殷剑峰 刘煜辉 《China Economist》 2007年第3期35-43,共9页
This article assesses both the domestic and external reasons for the occurrence of excessive liquidity.To solve the problem of excessive liquidity two different policy options are proposed;firstly the improvement of t... This article assesses both the domestic and external reasons for the occurrence of excessive liquidity.To solve the problem of excessive liquidity two different policy options are proposed;firstly the improvement of the structure of national income assignment and secondly the promotion of the structural diversification of foreign exchange assets. 展开更多
关键词 EXCESSIVE LIQUIDITY National INCOME assessment system Foreign exchange RESERVE management system
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Maize (Zea mays L.) Growth and Grain Yield under Conventional and Site-Specific Nitrogen Management in a Dryland Farming System
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作者 Suzan Mashego Brilliant Mareme Petja +1 位作者 Matshwene Edwin Moshia Shadrack Batsile Dikgwatlhe 《Journal of Agricultural Science and Technology(B)》 2014年第8期602-611,共10页
Large amount of pre-plant nitrogen (N) fertilizer results in low N use efficiency due to poor synchrony between soil N supply and maize N demand, especially during N sensitive growth stages. The objectives of the st... Large amount of pre-plant nitrogen (N) fertilizer results in low N use efficiency due to poor synchrony between soil N supply and maize N demand, especially during N sensitive growth stages. The objectives of the study were to compare growth and yield of maize (Zea rnays L.) under conventional and site-specific N management in a dryland farming system. The study, which was designed as randomized complete block design was conducted over three site-years under continuous maize cropping system in the semi-arid regions of the Limpopo Province in South Africa. Treatments of the study consisted of three N management strategies on a maize field planted to drought resistant SNK 2147 hybrid maize cultivar. Treatments were: (i) no N application (NO), (ii) site-specific N at variable rates ranging between 18 kg N/ha and 33 kg N/ha based on soil analysis results (N l) and (iii) conventional and uniform N application broadcasted during planting at 58 kg N/ha (N2). Sufficiency index as indication of N deficiency was determined using CCM-200 on maize leaves based on leaf numbers during maize vegetative growth stages V6, V10 and Vl4, and thereafter N was applied only when needed. The highest maize grain yield of 5.2 Mg/ha for N 1 was significantly higher (P 〈 0.05) than 3.2 Mg/ha and 4.0 Mg/ha of N0 and N2 in site-year I, respectively. Maize grain yield of 2.2 Mg/ha (Nl) at site-year ll was significantly higher (P _〈 0.05) than 1.7 Mg/ha of the NO. The maize growth and yield under N2 and N1 was compared, N1 required between 43% and 69% lesser N fertilizer as compared to N2 over site-years, and resulted in higher maize height, number of leaves per plant, leaf length, and leaf area than that of conventional N management strategy. Therefore, site-specific N management strategy sustains and improves growth and yield of maize using minimal N fertilizer as compared to conventional approach in low fertility soils of semi-arid regions in dryland farming systems. In examining the results of this study, there was a consistent benefit of site-specific N management strategy on improving growth and yield of maize while saving fertilizer use in small-scale dryland maize farming system. 展开更多
关键词 AFRICA maize grain yield nitrogen management precision agriculture
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Irrigating with cooler water does not reverse high temperature impact on grain yield and quality in hybrid rice
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作者 Wanju Shi Xinzhen Zhang +8 位作者 Juan Yang Somayanda M.Impa De Wang Yusha Lai Zijin Yang Hang Xu Jinshui Wu Jianhua Zhang S.V.Krishna Jagadish 《The Crop Journal》 SCIE CSCD 2023年第3期904-913,共10页
Rice grain yield and quality are negatively impacted by high temperature stress.Irrigation water temperature significantly affects rice growth and development,thus influencing yield and quality.The role of cooler irri... Rice grain yield and quality are negatively impacted by high temperature stress.Irrigation water temperature significantly affects rice growth and development,thus influencing yield and quality.The role of cooler irrigation water in counteracting high temperature induced damages in rice grain yield and quality are not explored.Hence,in the present study two rice hybrids,Liangyoupeijiu(LYPJ)and IIyou 602(IIY602)were exposed to heat stress and irrigated with water having different temperatures in a splitsplit plot experimental design.The stress was imposed starting from heading until maturity under field-based heat tents,over two consecutive years.The maximum day temperature inside the heat tents was set at 38℃.For the irrigation treatments,two different water sources were used including belowground water with cooler water temperature and pond water with relatively higher water temperature.Daytime mean temperatures in the heat tents were increased by 1.2–2.0℃ across two years,while nighttime temperature remained similar at both within and outside the heat tents.Cooler belowground water irrigation did have little effect on air temperature at the canopy level but decreased soil temperature(0.2–1.4℃)especially under control.Heat stress significantly reduced grain yield(33%to 43%),panicles m^(-2)(9%to 10%),spikelets m^(-2)(15%to 22%),grain-filling percentage(13%to 26%)and 1000-grain weight(3%to 5%).Heat stress significantly increased chalkiness and protein content and decreased grain length and amylose content.Grain yield was negatively related to air temperature at the canopy level and soil temperature.Whereas grain quality parameters like chalkiness recorded a significantly positive association with both air and soil temperatures.Irrigating with cooler belowground water reduced the negative effect of heat stress on grain yield by 8.8%in LYPJ,while the same effect was not seen in IIY602,indicating cultivar differences in their response to irrigation water temperature.Our findings reveal that irrigating with cooler belowground water would not significantly mitigate yield loss or improve grain quality under realistic field condition.The outcome of this study adds to the scientific knowledge in understanding the interaction between heat stress and irrigation as a mitigation tool.Irrigation water temperature regulation at the rhizosphere was unable to counteract heat stress damages in rice and hence a more integrated management and genetic options at canopy levels should be explored in the future. 展开更多
关键词 grain quality grain yield Hybrid rice High temperature IRRIGATION Water management
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Optimizing integrative cultivation management improves grain quality while increasing yield and nitrogen use efficiency in rice 被引量:20
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作者 ZHANG Hao HOU Dan-ping +8 位作者 PENG Xian-long MA Bing-ju SHAO Shi-mei JING Wen-jiang GU Jun-fei LIU Li-jun WANG Zhi-qin LIU Yuan-ying YANG Jian-chang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2019年第12期2716-2731,共16页
A major challenge in rice(Oryza sativa L.)production is to cope with increasing grain yield and fertilizer use efficiency without compromising grain quality.This study was designed to determine if optimizing integrati... A major challenge in rice(Oryza sativa L.)production is to cope with increasing grain yield and fertilizer use efficiency without compromising grain quality.This study was designed to determine if optimizing integrative cultivation management in rice could improve grain quality while increase yield and nitrogen use efficiency(NUE).An indica-japonica hybrid rice cultivar and a japonica rice cultivar were grown in the field,with five cultivation managements including no N application(0 N),local farmer's practice(LFP),and three optimizi ng in teg rati ve cultivati on managements,reducing N rate and increasi ng plant density(ND),ND+alternate wetting and moderate soil drying irrigation(NDW),and NDW+applying rapeseed cake fertilizer(NDWR).The results showed that the optimizi ng integrative cultivati on man ageme nts could not only in crease grain yield,but also enhance NUE compared to LFP.Compared to LFP,NDWR sign ifica ntly in creased brow n,milled,head milled rice rate,ratio of the kern el le ngth to breadth and breakdown value of starch,whereas decreased amylose content,gel consiste ncy,prolamin con tent,setback value,perce ntage of chalky kern els,and chalki ness.The three optimizing in tegrative cultivation managements increased con tents of total protei ns,albumin and glutelin,activities of the key enzymes involved in the sucrose-starch con version in grains,root oxidati on activity,and malic and succinic acid concentrations in root exudates during the grain-filling period.The results suggested that optimizing integrative cultivation managements could improve grain quality meanwhile increase grain yield and NUE by enhancing physiological activities of rice plants. 展开更多
关键词 RICE INTEGRATIVE CULTIVATION management YIELD grain quality nitrogen use efficiency
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Cold Plasma:A Potential Alternative for Rice Grain Postharvest Treatment Management in Malaysia 被引量:2
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作者 Mohd Fadthul Ikmal MISNAL Norizah REDZUAN +3 位作者 Muhamad Nor Firdaus ZAINAL Norhayati AHMAD Raja Kamarulzaman RAJA IBRAHIM Linda AGUN 《Rice science》 SCIE CSCD 2022年第1期1-15,共15页
Use of pesticides,herbicides and fertilizers is among the techniques to control insect pests and fungal pathogens.However,the technique is the major contributor to severe environmental implications in terms of air,wat... Use of pesticides,herbicides and fertilizers is among the techniques to control insect pests and fungal pathogens.However,the technique is the major contributor to severe environmental implications in terms of air,water and soil pollution.Besides,variable inconsistency becomes an important issue in the implementation of inclined bed dryers,leading to significant rice grain loss.Cold plasma technology has been widely proposed as a potential alternative for rice grain postharvest treatment management due to the presence of generated ionised gas that eventually produces reactive oxygen species or reactive nitrogen species.These species are used to decontaminate foodborne pathogens,mycotoxins and bacterial diseases.This review explores the current literature regarding cold plasma treatment technology,focusing on its efficiency as the microbial decontamination medium and insect pest mortality medium,and on the enhancement functional,nutritional and cooking properties,especially in rice grains.Previous studies have successfully demonstrated the ability of cold plasma treatment to significantly reduce the microbial count of foodborne pathogens,detoxify mycotoxins,and control seedborne rice seedling bacterial diseases.Previous studies have also proved that the implementation of cold plasma technology in postharvest management should be seriously considered for improving rice grain quantity and quality in Malaysia. 展开更多
关键词 rice grain postharvest management cold plasma microbial decontamination bacterial control
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Integrated management strategy for improving the grain yield and nitrogen-use efficiency of winter wheat 被引量:5
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作者 XU Hai-cheng DAI Xing-long +5 位作者 CHU Jin-peng WANG Yue-chao YIN Li-jun MA Xin DONG Shu-xin HE Ming-rong 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2018年第2期315-327,共13页
Understanding of how combinations of agronomic options can be used to improve the grain yield and nitrogen use efficiency(NUE) of winter wheat is limited. A three-year experiment involving four integrated management... Understanding of how combinations of agronomic options can be used to improve the grain yield and nitrogen use efficiency(NUE) of winter wheat is limited. A three-year experiment involving four integrated management strategies was conducted from 2013 to 2015 in Tai'an, Shandong Province, China, to evaluate changes in grain yield and NUE. The integrated management treatments were as follows: current practice(T1); improvement of current practice(T2); high-yield management(T3), which aimed to maximize grain yield regardless of the cost of resource inputs; and integrated soil and crop system management(T4) with a higher seeding rate, delayed sowing date, and optimized nutrient management. Seeding rates increased by 75 seeds m^-2 with each treatment from T1(225 seeds m^-2) to T4(450 seeds m^-2). The sowing dates were delayed from T1(5 th Oct.) to T2 and T3(8 th Oct.), and to T4 treatment(12 th Oct.). T1, T2, T3, and T4 received 315, 210, 315, and 240 kg N ha^-1, 120, 90, 210 and 120 kg P2O5 ha^-1, 30, 75, 90, and 45 kg K2O ha^-1, respectively. The ratio of basal application to topdressing for T1, T2, T3, and T4 was 6:4, 5:5, 4:6, and 4:6, respectively, with the N topdressing applied at regreening for T1 and at jointing stage for T2, T3, and T4. The P fertilizers in all treatments were applied as basal fertilizer. The K fertilizer for T1 and T2 was applied as basal fertilizer while the ratio of basal application to topdressing(at jointing stage) of K fertilizer for both T3 and T4 was 6:4. T1, T2, T3, and T4 were irrigated five, four, four and three times, respectively. Treatment T3 produced the highest grain yield among all treatments over three years and the average yield was 9 277.96 kg ha^-1. Grain yield averaged across three years with the T4 treatment(8 892.93 kg ha^-1) was 95.85% of that with T3 and was 21.72 and 6.10% higher than that with T1(7 305.95 kg ha^-1) and T2(8 381.41 kg ha^-1), respectively. Treatment T2 produced the highest NUE of all the integrated treatments. The NUE with T4 was 95.36% of that with T2 and was 51.91 and 25.62% higher than that with T1 and T3, respectively. The N uptake efficiency(UPE) averaged across three years with T4 was 50.75 and 16.62% higher than that with T1and T3, respectively. The N utilization efficiency(UTE) averaged across three years with T4 was 7.74% higher than that with T3. The increased UPE with T4 compared with T3 could be attributed mostly to the lower available N in T4, while the increased UTE with T4 was mainly due to the highest N harvest index and low grain N concentration, which consequently led to improved NUE. The net profit for T4 was the highest among four treatments and was 174.94, 22.27, and 28.10% higher than that for T1, T2, and T3, respectively. Therefore, the T4 treatment should be a recommendable management strategy to obtain high grain yield, high NUE, and high economic benefits in the target region, although further improvements of NUE are required. 展开更多
关键词 integrated management strategy grain yield winter wheat nitrogen use efficiency nitrogen uptake efficiency nitrogen utilization efficiency
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Integrated agronomic practices management improved grain formation and regulated endogenous hormone balance in summer maize (Zea mays L.) 被引量:1
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作者 YU Ning-ning ZHANG Ji-wang +2 位作者 LIU Peng ZHAO Bin REN Bai-zhao 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2020年第7期1768-1776,共9页
Compared with single agronomic practices management during grain formation, knowledge about integrated agronomic practices management on grain-filling characteristics and physiological function of endogenous hormones ... Compared with single agronomic practices management during grain formation, knowledge about integrated agronomic practices management on grain-filling characteristics and physiological function of endogenous hormones was limited. In order to clarify this issue, two field experiments, integrated agronomic practices management(IAPM), T1(local conventional cultivation practices), T2(an optimized combination of cropping systems and fertilizer treatment), T3(treatment based on high-yield studies), and T4(further optimized combination of cropping systems and fertilizer treatment), and nitrogen rate testing(NAT)(four nitrogen rates, 0, 129.0, 184.5, and 300.0 kg N ha–1) were performed with summer maize hybrid Zhengdan 958(ZD958). Results showed that with increased nitrogen rate, the endogenous hormone balance was promoted and the grain-filling characteristics were improved sufficiently to resulting in a significant increase in grain yield. However, the grain-filling characteristics deteriorated and yield was reduced with excessive nitrogen fertilization. However, IAPM could promote hormone balance and improve grain filling characteristic. The indole-3-acetic acid(IAA), zeatin riboside(ZR), and gibberellin(GA3) contents under T2 and T4 treatments were higher and the abscisic acid(ABA) content was lower, and the ZR and GA3 contents under T3 were higher than those under T1. Those resulted in the maximum grain-filling rate(Wmax) and the active grain-filling period(P) under T2, T3 and T4 were significantly increased than those under T1, and hence promoted kernel weight and grain yield. So IAPM promoted hormone balance by improving tillage model, optimizing fertilizer rate and fertilization period, appropriately increasing planting density and delaying harvest, which promoted grain filling rate and lengthened active grain-filling period, finally increased grain yield. 展开更多
关键词 grain fling endogenous hormone integrated agronomic practices management summer maize
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Innovation and practice of petroleum engineering synergetic management for the development of difficult-to-produce reserves 被引量:1
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作者 LIU Zhongyun 《Petroleum Exploration and Development》 2020年第6期1316-1324,共9页
Due to engineering technology and development costs,a considerable amount of proven oil and gas resources in China are difficult to develop,becoming reserves difficult to produce.Based on the successful development of... Due to engineering technology and development costs,a considerable amount of proven oil and gas resources in China are difficult to develop,becoming reserves difficult to produce.Based on the successful development of some domestic oil and gas reserves difficult to recover,this article summarizes the"four in one"petroleum engineering synergetic management model to promote the effective development of these reserves.This model draws on the essence of management theories,such as system theory,cybernetics and synergetic theory,and proposes the development idea of value creating and sharing for this type of reserves.By adopting the new management method of mechanism synergy,speciality synergy,process synergy and industrial chain synergy,this model effectively overcomes the decentralization of management responsibility,different management objectives,great risks of engineering and technological innovation,and the large number of uncertain factors in project construction,and can stimulate the vitality and power of active coordination of project participants,to effectively realize the synergetic innovation of engineering technology and synergetic cost reduction of the whole chain,reduction of the balanced oil price of the project,and dispersion of the project investment risk.By adopting this model,a large proportion of difficult-to-produce reserves have been liberated,realizing the effective utilization of the difficult-to-produce oil and gas resources,and making the reserves an important supplement to ensure national energy security. 展开更多
关键词 difficult-to-produce oil and gas reserves petroleum engineering engineering management synergetic innovation value creating and sharing energy security
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An International Survey on State of the Art of Grain Legume Management in Gene Banks
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作者 M. J. Suso M. Vishnyakova +2 位作者 A. Ramos G. Duc M. Ambrose 《Journal of Agricultural Science and Technology(B)》 2011年第7期975-981,共7页
An online survey addressed to members listed in the European Cooperative Programme for Crop Genetic Resources Networks Working Group on Graithe current problems in the management of GL germplasm, to work out the crite... An online survey addressed to members listed in the European Cooperative Programme for Crop Genetic Resources Networks Working Group on Graithe current problems in the management of GL germplasm, to work out the criterian Legumes and Grain Legumes (GL) germplasm managers and breeders was carded out to pinpoint and decisions involved in the implementation of regeneration procedures and to identify strategic areas where further research is required. The survey was divided into three sections: (1) germplasm collection details and current status of the regeneration needs; (2) assessment over the understanding of basic information required to carry out appropriate regeneration procedures such as the breeding systems, the pollination requirements and pollinating agents, the isolation techniques and regeneration facilities; and (3) assessment of different options, in addition to "ex situ", such as "in situ" and "on farm" conservation. Obtaining, collating and analysing different kinds of existing data on mating system of GL species, effective pollination control methods and isolation facilities by species and location is one example of a priority issue. The GL community makes a clear request for greater support for the development of well-designed methodologies of regeneration that maintain the genetic structure of populations and that the optimum regeneration strategy is most likely to be achieved through integrating pollinators with the regeneration procedures. A major concern of the GL community is the lack of empirical scientific information on the most suitable pollinator agents. 展开更多
关键词 grain legume germplasm collections GENEBANKS genetic resources management "ex situ" and "in situ" conservation regeneration procedures.
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Status and Development Countermeasures of Moderate-scale Management of Grain and Oil in Nanchong City
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作者 Chunlei PU Shaolin FANG +2 位作者 Wenbin HE Li LIU Feng LUO 《Asian Agricultural Research》 2019年第12期12-15,共4页
This paper introduces the development status of moderate-scale management of grain and oil in Nanchong,analyzes the existing problems in production and management,puts forward some suggestions in terms of fund,science... This paper introduces the development status of moderate-scale management of grain and oil in Nanchong,analyzes the existing problems in production and management,puts forward some suggestions in terms of fund,science and technology and industrial structure,and lists some cases for reference,so as to provide a direction for the operation of grain and oil in Nanchong. 展开更多
关键词 grain and OIL SCALE management STATUS Problem COUNTERMEASURE
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The construction and management of nature reserves in China
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作者 Jin Jianming National Environmental Protection Agency of China, Beijing 100035, China 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1997年第2期4-15,共12页
This article briefly outlines the construction and development of natural reserves; it embraces the necessity and main content of the mangement of natural reserves, including theoretical guidance, targets management, ... This article briefly outlines the construction and development of natural reserves; it embraces the necessity and main content of the mangement of natural reserves, including theoretical guidance, targets management, planning management, legislative management, technological management, administrative management. It discusses the experience of construction and management of natural reserves and existing problems in this regard as well as correspondent solutions such as policy measures, technology measures and management measures. 展开更多
关键词 natural reserve CONSTRUCTION management.
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Integrating innovative library e-reserves service into teaching and learning at Shanghai Jiao Tong University 被引量:3
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作者 Xiaohua SHI Xiaowei YU Wei PAN 《Chinese Journal of Library and Information Science》 2012年第2期45-58,共14页
Purpose: Fully integrating its e-reserves service into the university's course management system has become the primary design goal of the innovative e-reserves service system at Shanghai Jiao Tong University(SJTU... Purpose: Fully integrating its e-reserves service into the university's course management system has become the primary design goal of the innovative e-reserves service system at Shanghai Jiao Tong University(SJTU) Library.Design/methodology/approach: Through blending library and information service into the teaching and learning process, SJTU Library has effectively combined its reserves service into the user learning environment. The main metadata model and the design of various interfaces of the e-reserves service system are introduced.Findings: E-reserves has been integrated into the course management system. Users can directly access relevant resources when they browse the customized course page. It is more convenient for teachers to add reserves items, and the added items can be made available simultaneously on SJTU Library's resource discovery platform automatically.Research limitations: At present, e-reserves items are mainly books, and more other types of reserves materials are needed to be provided. Some relevant copyright issues should be addressed.Practical implications: Using a series of interface interactions, the e-reserves service has been integrated into the university's course management system. It is convenient for students to access customized e-reserves service during their learning process.Originality/value: We achieved interconnection between the e-reserves and the university's course management system. Information on the e-reserves Web page is automatically updated.SJTU Library provides customized e-reserves service in the course management system. 展开更多
关键词 Course reserves Course management system Innovative e-reserves service Customized reading Metadata conceptual model Interface interaction
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Effect of Nitrogen Regimes on Grain Yield,Nitrogen Utilization,Radiation Use Efficiency,and Sheath Blight Disease Intensity in Super Hybrid Rice 被引量:13
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作者 LI Di-qin TANG Qi-yuan +6 位作者 ZHANG Yun-bo QIN Jian-quan LI Hu CHEN Li-jun YANG Sheng-hai ZOU Ying-bin PENG Shao-bing 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2012年第1期134-143,共10页
Poor nitrogen use efficiency in rice production is a critical issue in China. Site-specific N managements (SSNM) such as real-time N management (RTNM) and fixed-time adjustable-dose N management (FTNM) improve f... Poor nitrogen use efficiency in rice production is a critical issue in China. Site-specific N managements (SSNM) such as real-time N management (RTNM) and fixed-time adjustable-dose N management (FTNM) improve fertilizer-N use efficiency of irrigated rice. This study was aimed to compare the different nitrogen (N) rates and application methods (FFP, SSNM, and RTNM methods) under with- and without-fungicide application conditions on grain yield, yield components, solar radiation use efficiency (RUE), agronomic-nitrogen use efficiency (AEN), and sheath blight disease intensity. Field experiments were carried out at Liuyang County, Hunan Province, China, during 2006 and 2007. A super hybrid rice Liangyou 293 (LY293) was used as experimental material. The results showed that RTNM and SSNM have great potential for improving agronomic-nitrogen use efficiency without sacrificing the grain yield. There were significant differences in light interception rate, sheath blight disease incidence (DI) and the disease index (ShBI), and total dry matter among the different nitrogen management methods. The radiation use efficiency was increased in a certain level of applied N. But, the harvest index (HI) decreased with the increase in applied N. There is a quadratic curve relationship between grain yield and applied N rates. With the same N fertilizer rate, different fertilizer-N application methods affected the RUE and grain yield. The fungicide application not only improved the canopy light interception rate, RUE, grain filling, and harvest index, but also reduced the degree of sheath blight disease. The treatment of RTNM under the SPAD threshold value 40 obtained the highest yield. While the treatment of SSNM led to the highest nitrogen agronomic efficiency and higher rice yield, and decreased the infestation of sheath blight disease dramatically as well. Nitrogen application regimes and diseases control in rice caused obvious effects on light interception rate, RUE, and HI. Optimal N rate is helpful to get higher light interception rate, RUE, and HI. Disease control with fungicide application decreased and delayed the negative effects of the high N on rice yield formation. SSNM and RTNM under the proper SPAD threshold value obtained high-yield with high efficiency and could alleviate environmental pollution in rice production. 展开更多
关键词 super hybrid rice real-time N management fixed-time adjustable-does N management grain yield sheath blight radiation use efficiency agronomic-nitrogen use efficiency
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Grain-filling characteristics and yield differences of maize cultivars with contrasting nitrogen efficiencies 被引量:9
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作者 Qiang Li Lunjing Du +4 位作者 Dongju Feng Yun Ren Zhexin Li Fanlei Kong Jichao Yuan 《The Crop Journal》 SCIE CSCD 2020年第6期990-1001,共12页
To investigate the effect of nitrogen management on the grain-filling characteristics and yield formation of maize cultivars with contrasting nitrogen efficiencies,and to identify differences in grain-filling characte... To investigate the effect of nitrogen management on the grain-filling characteristics and yield formation of maize cultivars with contrasting nitrogen efficiencies,and to identify differences in grain-filling characteristics and yield of maize cultivars in response to nitrogen management,a two-year field experiment was conducted in southwest China in2015–2016.The grain-filling rate and duration of the N-inefficient cultivar XY 508 were higher than those of the N-efficient cultivar ZH 311.The 100-kernel weight of XY 508 was significantly higher than that of ZH 311.The kernel number per ear of ZH 311 was significantly higher than that of XY 508,making the population filling rate of ZH 311 significantly higher than that of XY 508.The higher population filling rate of the N-efficient maize cultivar led to a significant yield advantage over the N-inefficient maize cultivar.Nitrogen management effectively improved maize grain yield,but the response of maize cultivars with contrasting nitrogen efficiencies to nitrogen management was inconsistent.A basal fertilizer ratio 60.43%with a topdressing ratio 39.57%effectively increased grainfilling rate,delayed the time to maximum filling rate,prolonged the active filling period and effective grain-filling time,increased the 100-kernel weight,and maintained higher kernels per ear,thereby improving the population filling rate and maximizing the yield advantage of the N-efficient cultivar.A 100%basal fertilizer ratio not only increased the number of kernels per ear,but also maintained high grain filling characteristics to obtain a higher 100-kernel weight and increased the population filling rate,leading to a high grain yield in the N-inefficient cultivar.Thus,the 100%basal fertilizer ratio partially compensated for the deficient grain yield of the N-inefficient cultivar. 展开更多
关键词 MAIZE grain filling Nitrogen management YIELD Population filling rate
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Changes in Grain Yield of Rice and Emission of Greenhouse Gases from Paddy Fields after Application of Organic Fertilizers Made from Maize Straw 被引量:4
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作者 MA Yi-hu GU Dao-jian +3 位作者 LIU Li-jun WANG Zhi-qin ZHANG Hao YANG Jian-chang 《Rice science》 SCIE 2014年第4期224-232,共9页
A field experiment was conducted at the farm of Yangzhou University, Yangzhou, China, to study the effects of organic fertilizers made from maize straw on rice grain yield and the emission of greenhouse gases. Four or... A field experiment was conducted at the farm of Yangzhou University, Yangzhou, China, to study the effects of organic fertilizers made from maize straw on rice grain yield and the emission of greenhouse gases. Four organic fertilizer treatments were as follows: maize straw (MS), compost made from maize straw (MC), methane-generating maize residue (MR), and black carbon made from maize straw (BC). These organic fertilizers were applied separately to paddy fields before rice transplanting. No organic fertilizer was applied to the control (CK). The effects of each organic fertilizer on rice grain yield and emission of greenhouse gases were investigated under two conditions, namely, no nitrogen (N) application (ON) and site-specific N management (SSNM). Rice grain yields were significantly higher in the MS, MC and MR treatments than those in CK under either ON or SSNM. The MS treatment resulted in the highest grain yield and agronomic N use efficiency. However, no significant difference was observed for these parameters between the BC treatment and CK. The changes in the emissions of methane (CH4) carbon dioxide (CO2), or nitrous oxide (N20) from the fields were similar among all organic fertilizer treatments during the entire rice growing season. The application of each organic fertilizer significantly increased the emission of each greenhouse gas (except N20 emission in the BC treatment) and global warming potential (GWP). Emissions of all the greenhouse gases and GWP increased under the same organic fertilizer treatment in the presence of N fertilizer, whereas GWP per unit grain yield decreased. The results indicate that the application of organic fertilizer (MS, MC or MR) could increase grain yield, but also could enhance the emissions of greenhouse gases from paddy fields. High grain yield and environmental efficiency could be achieved by applying SSNM with MR. 展开更多
关键词 organic fertilizer site-specific nitrogen management RICE grain yield greenhouse gas maize straw
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Simulation of Artificial Grain Feeding in Order to Reach Dynamical Bed Stabilisation Along the River Rhine
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作者 Thomas WENKA 《四川大学学报(工程科学版)》 EI CAS CSCD 北大核心 2005年第S1期57-63,共7页
The Wesel-Xanten stretch of the fiver Rhine between km-812.5 and km-821.5 is one of the reaches where strong erosion leads to high maintenance efforts conceming navigability.In order to improve the naviga- tion condit... The Wesel-Xanten stretch of the fiver Rhine between km-812.5 and km-821.5 is one of the reaches where strong erosion leads to high maintenance efforts conceming navigability.In order to improve the naviga- tion conditions without aggravating the flood protection,but also ensuring that the ecological system of the river is not damaged,investigations of the morphodynamical processes in connection with artificial grain feeding ac- tivities have to be carried out by Federal Waterways Engineering and Research... 展开更多
关键词 rhine river wesel-xanten artificial grain feeding sediment management graded sediment transport 2D depth-average numerical model
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Grain Macro-Control Mechanism Research
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《International English Education Research》 2014年第10期71-73,共3页
this paper based on the food security, the food the macroeconomic regulation and control of the operation mechanism of the general theory, focus on the China's grain macroeconomic regulation and control mechanism, th... this paper based on the food security, the food the macroeconomic regulation and control of the operation mechanism of the general theory, focus on the China's grain macroeconomic regulation and control mechanism, the concept of grain macroeconomic regulation and control mechanism, the grain circulation macroeconomic regulation and control tool application, grain circulation macroeconomic regulation and control system, the problem of grain circulation system, food price formation mechanism. Through the research set up grain control of the operation mechanism of general theory. 展开更多
关键词 macroeconomic management food economy grain macro-control mechanism regulation and
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China's grain macroeconomic regulation and control strategy of economic strategy research
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作者 Zhiqiang Feng 《International Journal of Technology Management》 2013年第3期115-118,共4页
this article through to the national food security problems, and puts forward China's grain macro-control mechanism is to follow the food economic law, with the national food security as the foundation, the food econ... this article through to the national food security problems, and puts forward China's grain macro-control mechanism is to follow the food economic law, with the national food security as the foundation, the food economy structure adjustment as power, based on production and supply balance, trade and consumption balance, price and social grain total cost balance, grain reserves and the retaining rate balance four as the key point, establish and perfect the food security is the core of the production, processing, trade, reserve, consumption for control system, perfect the government macroeconomic regulation and control of the market, protect the food producers and consumers' vital interests, early warning and solving the international and domestic food crisis and risk, maintain food markets continue to stability and promote national economic security of food. 展开更多
关键词 macroeconomic management food economy grain macro-control mechanism the national food security
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Risk-constrained Energy Management Strategy for a Commercial Campus Considering Comprehensive Reserves Against Islanding Conditions
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作者 Zheming Liang Desong Bian +1 位作者 Xiaohu Zhang Di Shi 《CSEE Journal of Power and Energy Systems》 SCIE EI CSCD 2023年第5期1797-1807,共11页
This paper proposes an optimal risk-constrained energy management strategy for commercial buildings in a commercial campus with islanding capabilities.The goal is to minimize the total operation and maintenance costs,... This paper proposes an optimal risk-constrained energy management strategy for commercial buildings in a commercial campus with islanding capabilities.The goal is to minimize the total operation and maintenance costs,while maximizing comprehensive comfort levels for the occupants.A two-stage riskconstrained,scenario-based stochastic optimization approach is adopted to handle various uncertainties associated with the energy management process,such as power generation of rooftop solar panels,arrival state-of-charges,and arrival/departure time of plug-in electric vehicles,intermittent load demand,and uncertain grid-connection conditions.A conditional-valueat-risk method is introduced to provide a risk-averse energy management strategy.To face the challenge of both reducing the computational burden and maintaining the accuracy of the stochastic programming,an advanced scenario reduction method is leveraged.Extensive simulation results validate the effectiveness of the proposed energy management strategy for minimizing total operating and maintenance costs of commercial buildings with islanding capabilities,while maximizing comprehensive comfort levels of the occupants. 展开更多
关键词 Comprehensive comfort levels CVAR energy management islanding capability RESERVE stochastic programming uncertainty
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