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Zoning Control of Health of Farmland System
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作者 Ziwei WANG Peng FAN +2 位作者 Lei WANG Xihui YANG Qingwei YANG 《Meteorological and Environmental Research》 2023年第6期69-72,共4页
In addition to the quality and quantity of farmland, the health of farmland has also become an important research direction in the field of farmland protection. In order to comprehensively evaluate the relationship an... In addition to the quality and quantity of farmland, the health of farmland has also become an important research direction in the field of farmland protection. In order to comprehensively evaluate the relationship and distribution of health and farmland production capacity, the depression area behind the Yellow River in Henan Province is taken as the research object. Using production capacity evaluation data and system health evaluation results, the health status and production capacity of farmland in the region are coupled. The results show that high productivity farmland is most distributed in areas with moderate health risks, while low productivity farmland is more distributed in areas with low health risks. Based on their coupling characteristics, the depression area behind the Yellow River can be divided into five types, and management and protection strategies can be formulated separately. 展开更多
关键词 farmland health Healthy production capacity Zoning control
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Impact of slope farmland use change on ecosystem services value in China,2000-2020
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作者 ZENG Jie BIAN Jiao-jiao CHEN Wan-xu 《Journal of Mountain Science》 SCIE CSCD 2023年第3期821-833,共13页
Slope farmland is an important component of farmland resources in China.The utilization and change of slope farmland have significant effects on ecosystems,and understanding the impact of slope farmland change on ecos... Slope farmland is an important component of farmland resources in China.The utilization and change of slope farmland have significant effects on ecosystems,and understanding the impact of slope farmland change on ecosystem services(ESs)is critical for effective land utilization and ecosystem protection.This study aims to analyze slope farmland changes in China between 2000 and 2020 and quantify the impact of these changes on ESs by the use of a land use dynamic attitude study,and an ecosystem services value(ESV)equivalent.Results show that the area of slope farmland in China was mainly concentrated on slopes of 2°-6°,and exhibited a downward trend between 2000 and 2020.There were significant differences in the spatial distribution of the farmland,which was mainly located in the Taihang,Qinling,Wushan,and Xuefeng mountains.ESV increased by$179.235 million due to the conversion between slope farmland and forest,grassland,and construction land from 2000-2010.Conversely,from 2010 to 2020,ESV decreased by$2613.919 million due to the conversion of forest and grassland to slope farmland as well as the conversion of slope farmland to construction land. 展开更多
关键词 Slope farmland change Revised benefit transfermethod Ecosystemservicesvalue Ecosystem services management Slope farmland utilization China
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Construction of Legal System of China's Farmland Protection under the Coexistence of Multiple Objectives:Historical Logic,Practical Problems and Optimization Paths
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作者 Shengnan MA Jiaxin ZHOU Yongfang YANG 《Asian Agricultural Research》 2023年第2期26-34,38,共10页
[Objectives]To explore the evolution of the legal system of farmland protection and explore the rules and characteristics of policy development based on the theory and logic of institutional change since China's r... [Objectives]To explore the evolution of the legal system of farmland protection and explore the rules and characteristics of policy development based on the theory and logic of institutional change since China's reform and opening up,reveal the problems and deep-seated reasons of its legislation,clarify the direction of farmland protection in the new period,and solve the"non-agricultural""non-grain"and ecological problems of farmland.[Methods]Literature analysis and inductive deduction methods were used.[Results]The evolution of the farmland protection legal system has gone through the process of"national consciousness-policy guidelines-institutional system",the change from"single subject to multiple subjects";change from the use of"one-way administrative means to coordinated use of administrative,economic and technical means".The practical problems of the farmland protection legal system are mainly due to the insufficient systematization of the farmland protection legal system itself,the generalization of quantity protection,the transformation of quality protection,and the absence of ecological protection.[Conclusions]It is recommended to improve the existing farmland protection legal system from the establishment of the Farmland Protection Law,the improvement of the farmland protection public participation mechanism and supervision mechanism,the establishment of the farmland quality construction and improvement system,the differentiated farmland occupation and supplementation balance system,and the ecological restoration system. 展开更多
关键词 farmland protection Legal system construction Policy evolution Existing problems Optimization path
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Promoting grain production through high-standard farmland construction:Evidence in China
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作者 Shuai Hao Guogang Wang +4 位作者 Yantao Yang Sicheng Zhao Shengnan Huang Liping Liu Huanhuan Zhang 《Journal of Integrative Agriculture》 SCIE CSCD 2024年第1期324-335,共12页
Food security is a strategic priority for a country’s economic development.In China,high-standard farmland construction(HSFC)is an important initiative to stabilize grain production and increase grain production capa... Food security is a strategic priority for a country’s economic development.In China,high-standard farmland construction(HSFC)is an important initiative to stabilize grain production and increase grain production capacity.Based on panel data from 31 sample provinces,autonomous regions,and municipalities in China from 2005–2017,this study explored the impact of HSFC on grain yield using the difference-in-differences(DID)method.The results showed that HSFC significantly increased total grain production,which is robust to various checks.HSFC increased grain yield through three potential mechanisms.First,it could increase the grain replanting index.Second,it could effectively reduce yield loss due to droughts and floods.Last,HSFC could strengthen the cultivated land by renovating the low-and medium-yielding fields.Heterogeneity analysis found that the HSFC farmland showed a significant increase in grain yield only in the main grain-producing areas and balanced areas.In addition,HSFC significantly increased the yields of rice,wheat,and maize while leading to a reduction in soybean yields.The findings suggest the government should continue to promote HSFC,improve construction standards,and strictly control the“non-agriculturalization”and“non-coordination”of farmland to increase grain production further.At the same time,market mechanisms should be used to incentivize soybean farming,improve returns and stabilize soybean yields. 展开更多
关键词 high-standard farmland farmland construction food security food production area DIFFERENCE-IN-DIFFERENCES
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Study on Environmental Risk and Economic Benefits of Rotation Systems in Farmland of Erhai Lake Basin 被引量:4
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作者 TANG Qiu-xiang REN Tian-zhi +4 位作者 Wilko Schweers LIU Hong-bin LEI Bao-kun LIN Tao ZHANGGui-long 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2012年第6期1038-1047,共10页
This study was designed to find out an optimised planting system of reducing non-point (source) pollution by analyzing the reasons and the factors of influence non-point pollution in farmland of Erhai Lake basin. Th... This study was designed to find out an optimised planting system of reducing non-point (source) pollution by analyzing the reasons and the factors of influence non-point pollution in farmland of Erhai Lake basin. The results showed that incomes, residual nitrogen in soil, and the loss of nitrogen in surface water in rice-garlic system were higher than those in rice-fava bean system. There were positive correlations between the nitrogen loss of farmland, nitrogen inputs, residual nitrogen in soil, and incomes of farmland. Economic benefits and environment benefits are both appropriate, if the area of rice-garlic system would be reduced to 53% and the area of rice-fava bean system increased to 36% of total cropping area in the investigated watershed. Adjustment of planting structure and introduction of reasonable rotation systems is considered an effective measure of controlling agricultural non-point pollution in watersheds of Erhai Lake. 展开更多
关键词 watershed management Erhai Lake farmland crop rotation environmental risk economic benefits
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Effect of free-air CO_2 enrichment on nematode communities in a Chinese farmland ecosystem 被引量:2
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作者 LIQi LIANGWen-ju +2 位作者 JIANGYong ZHUJian-guo KONGChui-hua 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2005年第1期72-75,共4页
At a rice wheat rotational free air CO 2 enrichment(FACE) platform, the effect of elevated atmospheric CO 2 on soil nematode communities in a farmland ecosystem was studied. Wheat plots were exposed to elevated atmosp... At a rice wheat rotational free air CO 2 enrichment(FACE) platform, the effect of elevated atmospheric CO 2 on soil nematode communities in a farmland ecosystem was studied. Wheat plots were exposed to elevated atmospheric CO 2(ambient 370 μl/L + 200 μl/L). 32 families and 40 genera of nematode were observed in soil suspensions during the study period. Under FACE treatment, the numbers of total nematodes, bacterivores and fungivores exhibited an increasing trend. Because of the seasonal variation of soil temperature and moisture, the effect of elevated atmospheric CO 2 on soil nematodes was only observed under favorable conditions. The response of nematode communities to elevated atmospheric CO 2 may indicate the change of soil food web. 展开更多
关键词 nematode community trophic group free-air CO_2 enrichment(FACE) WHEAT farmland ecosystem
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THE STRUCTURE AND DYNAMICS OF THE LAND RESOURCES SYSTEM IN THE FARMLAND SHELTER FOREST REGION IN THE NORTHEAST PLAIN
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作者 张柏 《Chinese Geographical Science》 SCIE CSCD 1994年第4期322-332,共11页
(张柏)THESTRUCTUREANDDYNAMICSOFTHELANDRESOURCESSYSTEMINTHEFARMLANDSHELTERFORESTREGIONINTHENORTHEASTPLAIN¥Zhang... (张柏)THESTRUCTUREANDDYNAMICSOFTHELANDRESOURCESSYSTEMINTHEFARMLANDSHELTERFORESTREGIONINTHENORTHEASTPLAIN¥ZhangBai(ChangchunInst... 展开更多
关键词 LAND RESOURCES system LAND reclamation farmland SHELTER forest NORTHEAST PLAIN remote sensing
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A New Rainwater Harvesting and Recycling System for Transforming Sloping Land into Terraced Farmland
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作者 SHI Yuan-zhi WANG Yue-hong +2 位作者 CUI Yuan-lai WANG Shi-wu ZHANG Yu-shuai 《Journal of Mountain Science》 SCIE CSCD 2014年第1期205-214,共10页
Transforming sloping land into terraced land is an effective approach to cope with the problems including farmland shortage and severe soil erosion.This paper introduces a new system based on rainwater harvesting and ... Transforming sloping land into terraced land is an effective approach to cope with the problems including farmland shortage and severe soil erosion.This paper introduces a new system based on rainwater harvesting and recycling technology,which may effectively improve farmland productivity rainwater use efficiency and reduce water and fertilizer inputs.The new system consists of three subsystems:1) A plough layer with the dual function of crop cultivation and rainwater harvesting; 2) A tank below the plough layer for storing water; 3) An irrigation-drainage subsystem.The plough layer and the storage tank,both treated for reducing seepage,are connected through the irrigation and drainage system.Results showed that,compared with the traditional paddy fields,rice evapotranspiration( and crop coefficient) in the test field remained at a similar level,while the irrigation amount was reduced by 44.3% under the condition of basin irrigation,and the drainage amount decreased by 86.6%,and the non-point source pollution was reduced to 67.7%~87.9%,and the rainwater utilization efficiency increased by 30% and reached 95.4%,and crop yield of middle-season rice reached 9,975 kg/hm2,which was only 0.4% lower than that in the traditional paddy field in the terms of dry matter.The new technology sheds light on new possibilities for transformation of hilly sloping land. 展开更多
关键词 Hills Sloping LAND Terraced farmland RAINWATER HARVESTING RECYCLING
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The Dynamics and Driving Force of Farmland Ecosystem Productivity
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作者 ZHONGLiang-ping SHAOMing-an LIYu-shan 《Agricultural Sciences in China》 CAS CSCD 2005年第1期34-40,共7页
Based on the experimental data of crop yield, soil water and fertility of a dryland farming ecosystem in northwest China, asystematic analysis is carried out to study the dynamics of dryland farming ecosystem producti... Based on the experimental data of crop yield, soil water and fertility of a dryland farming ecosystem in northwest China, asystematic analysis is carried out to study the dynamics of dryland farming ecosystem productivity and its limitingfactors. This paper also discusses which of the two limiting factors, i.e., soil water or fertility, is the primary factor and theirdynamics. The result shows that fertility is the primary limiting factor when the productivity is rather low. As chemicalfertilizer input increases and the productivity promotes, water gradually becomes the primary limiting factor. Chemicalfertilizers and plastic film mulching are the two major driving forces that determine the crop productivity and its stabilityin these areas. 展开更多
关键词 farmland ecosystem PRODUCTIVITY Limiting factors DYNAMICS Driving force
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Design of Farmland Water Conservancy and Irrigation Management System Based on GIS
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作者 Feng ZHANG Linying DONG 《Asian Agricultural Research》 2017年第11期41-43,共3页
The farmland irrigation project is an important part of China's water conservancy project. To keep abreast of the farmland water conservancy and various related environmental parameters,we can use the external sen... The farmland irrigation project is an important part of China's water conservancy project. To keep abreast of the farmland water conservancy and various related environmental parameters,we can use the external sensors to acquire real-time data,employ the computer technology,networking and communication technology,database technology,geographic information system( GIS) technology,component technology and other advanced modern information technologies combined with the automated water conservancy technology,in order to build an accurate,efficient,fast,comprehensive,standardized decision support system integrating farmland water conservancy and irrigation information collection,transmission,storage,management and analysis. In this paper,we give details about the overall framework design of farmland water conservancy and irrigation management system based on GIS,information collection and data input,and information processing and data output,to provide a reference for the digital water conservancy construction in China. 展开更多
关键词 GIS farmland water conservancy farmland irrigation Data information
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The Innovation and Plights of Farmland Property Rights System Reform in Chongqing Municipality
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作者 ZHENG Cai-gui1,ZHANG Xiao-cheng1,HE Jiang-hua2,LI Ji-zhuang1,LIANG Qi-xue1 1. Chongqing Institute of Land Surveying and Planning,Chongqing 400020,China 2. School of Management,Sichuan University of Arts and Science,Dazhou 635000,China 《Asian Agricultural Research》 2010年第4期57-60,共4页
Based on the background of national urban and rural comprehensive reform pilot area and the introduction of the profiles of research region and the data obtained by on-the-spot interview survey,the innovative models o... Based on the background of national urban and rural comprehensive reform pilot area and the introduction of the profiles of research region and the data obtained by on-the-spot interview survey,the innovative models of farmland property rights system reform in Chongqing are introduced by applying participatory rural appraisal methods and examples. The innovative models cover buying shares of contract management rights,transforming from farmers to townspeople and mortgaging contract management rights. The plights exist in the reform are analyzed,among which the plights of buying shares of contract management rights are introduced from the following five aspects:the conflict with the present land contract laws,the possible new round of massive scale land loses,the confounded functions of government and enterprise caused by risk transference and the difficulties of handling assets when the contract management rights expired. Besides,the plights of the transforming from rural residents to urban residents are analyzed from four aspects,which include the particularity of reform,high financial pressure,emergence of interbedded people and difficulties of payoff of village-based companies. From the facets of limited mortgage area,risks of reimbursing the loan,legal risks of mortgage. The results show that the stock purchasing model of contractual management rights reveals the capital value of land and the model is of theoretical and practical significance in law and economics. However,the social security system is not perfect,so the stock purchasing model of contractual management rights can not be expanded. In addition,the participation of more famers and the expansion of enterprises are limited as well. The land comprehensive reform model of transforming from rural residents to urban residents is of positive significance to the comprehensive exploration of farmland property system reform,but this kind of model should be supported by strong economy. The stock purchasing model of contractual management rights is of significance to perfect the contractual management rights,but it conflicts with the existing laws and financial systems. 展开更多
关键词 farmland property RIGHTS PARTICIPATORY rural appra
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An Improved Farmland Fertility Algorithm with Hyper-Heuristic Approach for Solving Travelling Salesman Problem
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作者 Farhad Soleimanian Gharehchopogh Benyamin Abdollahzadeh Bahman Arasteh 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第6期1981-2006,共26页
Travelling Salesman Problem(TSP)is a discrete hybrid optimization problem considered NP-hard.TSP aims to discover the shortest Hamilton route that visits each city precisely once and then returns to the starting point... Travelling Salesman Problem(TSP)is a discrete hybrid optimization problem considered NP-hard.TSP aims to discover the shortest Hamilton route that visits each city precisely once and then returns to the starting point,making it the shortest route feasible.This paper employed a Farmland Fertility Algorithm(FFA)inspired by agricultural land fertility and a hyper-heuristic technique based on the Modified Choice Function(MCF).The neighborhood search operator can use this strategy to automatically select the best heuristic method formaking the best decision.Lin-Kernighan(LK)local search has been incorporated to increase the efficiency and performance of this suggested approach.71 TSPLIB datasets have been compared with different algorithms to prove the proposed algorithm’s performance and efficiency.Simulation results indicated that the proposed algorithm outperforms comparable methods of average mean computation time,average percentage deviation(PDav),and tour length. 展开更多
关键词 Travelling salesman problem optimization farmland fertility optimization algorithm Lin-Kernighan
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Effects of nitrogen and phosphorus additions on soil microbial community structure and ecological processes in the farmland of Chinese Loess Plateau
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作者 KOU Zhaoyang LI Chunyue +5 位作者 CHANG Shun MIAO Yu ZHANG Wenting LI Qianxue DANG Tinghui WANG Yi 《Journal of Arid Land》 SCIE CSCD 2023年第8期960-974,共15页
Microorganisms regulate the responses of terrestrial ecosystems to anthropogenic nutrient inputs.The escalation of anthropogenic activities has resulted in a rise in the primary terrestrial constraining elements,namel... Microorganisms regulate the responses of terrestrial ecosystems to anthropogenic nutrient inputs.The escalation of anthropogenic activities has resulted in a rise in the primary terrestrial constraining elements,namely nitrogen(N)and phosphorus(P).Nevertheless,the specific mechanisms governing the influence of soil microbial community structure and ecological processes in ecologically vulnerable and delicate semi-arid loess agroecosystems remain inadequately understood.Therefore,we explored the effects of different N and P additions on soil microbial community structure and its associated ecological processes in the farmland of Chinese Loess Plateau based on a 36-a long-term experiment.Nine fertilization treatments with complete interactions of high,medium,and low N and P gradients were set up.Soil physical and chemical properties,along with the microbial community structure were measured in this study.Additionally,relevant ecological processes such as microbial biomass,respiration,N mineralization,and enzyme activity were quantified.To elucidate the relationships between these variables,we examined correlation-mediated processes using statistical techniques,including redundancy analysis(RDA)and structural equation modeling(SEM).The results showed that the addition of N alone had a detrimental effect on soil microbial biomass,mineralized N accumulation,andβ-1,4-glucosidase activity.Conversely,the addition of P exhibited an opposing effect,leading to positive influences on these soil parameters.The interactive addition of N and P significantly changed the microbial community structure,increasing microbial activity(microbial biomass and soil respiration),but decreasing the accumulation of mineralized N.Among them,N24P12 treatment showed the greatest increase in the soil nutrient content and respiration.N12P12 treatment increased the overall enzyme activity and total phospholipid fatty acid(PLFA)content by 70.93%.N and P nutrient contents of the soil dominate the microbial community structure and the corresponding changes in hydrolytic enzymes.Soil microbial biomass,respiration,and overall enzyme activity are driven by mineralized N.Our study provides a theoretical basis for exploring energy conversion processes of soil microbial community and environmental sustainability under long-term N and P additions in semi-arid loess areas. 展开更多
关键词 nitrogen and phosphorus additions microbial community structure farmland ecosystem nitrogen mineralization soil enzyme activity
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Influence of Straw Incorporation on Maize Yield,N Accumulation and Remobilization on Slope Farmland in Northeast China
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作者 Dai Jian-jun Liu Hong-fei +2 位作者 Li Hang Liu Zhao-ting Wu Hai-feng 《Journal of Northeast Agricultural University(English Edition)》 CAS 2023年第2期55-67,共13页
Slope farmland is a main type of agricultural land throughout northeast China.Long-term high intensity utilization and unreasonable farming have caused the deterioration of soil resources and a decrease in crop produc... Slope farmland is a main type of agricultural land throughout northeast China.Long-term high intensity utilization and unreasonable farming have caused the deterioration of soil resources and a decrease in crop production.Here,it was hypothesized that crop straw incorporation might help to reduce nutrient losses and increase maize yields across time and space.A field experiment for testing straw management practices on maize across three slope positions(top,back and bottom slopes)was conducted in Northeast China in 2018 and 2019.In this study,the dry matter accumulation(DMA),N accumulation(NA),N remobilization,postsilking N uptake and grain yield were measured under SI(straw incorporation)and NSI(no straw incorporation)across three slope positions of 100-m-long consecutive black soil slope farmland during the maize(Zea mays L.)growth stages.Compared with NSI,SI significantly increased DMA and NA at the silking and maturity stages.SI typically increased the N remobilization in all slope positions,and significantly increased N remobilization efficiency and contribution of N remobilization to grain on the back and bottom slopes.However,post-silking N uptake was only increased by SI on the top slope.SI generally increased the crop yield in three slope positions.In the SI treatments,the bottom slope was the highest yield position,followed by the top,and then the back slopes,suggesting that the bottom slope position of regularly incorporated straw might have increased the potential for boosting maize yield.Overall,the study demonstrated the outsized potential of straw incorporation to enhance maize NA and then increase the grain yield in black soil slope farmland. 展开更多
关键词 dry matter N accumulation N remobilization crop yield black soil slope farmland MAIZE
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俯仰式播种单体仿形性能检测试验台设计与试验
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作者 衣淑娟 李怡凯 +2 位作者 陈继国 王淞 赵斌 《农业机械学报》 EI CAS CSCD 北大核心 2024年第2期90-100,共11页
为解决播种单体仿形机构性能难以检测的问题,设计了俯仰式播种单体仿形性能检测试验台。阐述了试验台组成结构与工作原理,对其高速传动系统、液压升降系统、监控系统以及关键部件参数进行设计。应用ANSYS软件对台架整体和关键部件进行... 为解决播种单体仿形机构性能难以检测的问题,设计了俯仰式播种单体仿形性能检测试验台。阐述了试验台组成结构与工作原理,对其高速传动系统、液压升降系统、监控系统以及关键部件参数进行设计。应用ANSYS软件对台架整体和关键部件进行静力学分析和模态分析,验证结构设计的合理性。为检验俯仰式播种单体仿形性能检测试验台的实际检测效果,以德邦大为1205型牵引式免耕精量播种机播种单体为研究对象,先以液压杆伸出量与传送带速度为试验因素,以监控系统误差为评价指标进行试验。试验得出,在液压杆伸出量为0~200 mm范围内,监控系统角度传感器最大误差为0.69 mm;在传送带速度8~19 km/范围内,光电编码器最大误差为0.18 km/h。确认监控系统准确性后,再以单体速度为试验因素,采集速度8、10、12 km/h下地块的起伏数据为目标曲线,以地形起伏模拟曲线的绝对误差平均值为指标进行单因素试验,试验得出,所设计的试验台可有效模拟田间地面的起伏频率与起伏量,绝对误差平均值为1.86 mm,满足播种单体仿形性能检测需求。 展开更多
关键词 高速播种机 仿形机构 试验台架 农田地形 液压系统
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粮食安全视角下农田灌溉系统的功能演进、现实困境与治理对策
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作者 穆月英 王镜淳 《中州学刊》 北大核心 2024年第5期32-40,共9页
粮食安全是建设农业强国的必然要求,农田灌溉系统是保障粮食安全的基础,二者在乡村社会的交织,体现为农田灌溉系统的多重属性。以“物质-技术-制度”的多重属性为理论基础,探究农田灌溉系统的对粮食安全的作用机制,明确农田灌溉系统的... 粮食安全是建设农业强国的必然要求,农田灌溉系统是保障粮食安全的基础,二者在乡村社会的交织,体现为农田灌溉系统的多重属性。以“物质-技术-制度”的多重属性为理论基础,探究农田灌溉系统的对粮食安全的作用机制,明确农田灌溉系统的功能演进和现实困境的本质,对于实现农业可持续发展和乡村治理有效具有重要意义。我国农田灌溉系统的功能演进体现在“数量-质量-生态”物质属性功能的渐进发展、“水-能-粮耦合”技术属性功能的体系建构、“多元参与”制度属性功能的建设格局,现实困境表现为气候变化引致的设施脆弱性困境、“大国小农”引致的技术推广困境、主体缺位和机制失灵引发的管护困境。为此,全方位夯实粮食安全根基,必须以综合可持续为目标建设农田灌溉设施,以产权和价格机制为杠杆提升农田灌溉系统市场化供给水平,以协同治理为抓手加强农田灌溉系统管护,从而促进农田灌溉系统的效能发挥。 展开更多
关键词 粮食安全 农田灌溉系统 “物质-技术-制度”属性 治理对策
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农田灌溉光伏水泵系统性能测试分析
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作者 高林朝 张香萍 +4 位作者 谢毅 胡国华 孙润超 贾兵 王光 《河南农业大学学报》 CAS CSCD 北大核心 2024年第1期106-114,共9页
【目的】探究农田灌溉光伏水泵系统综合用能需求特性,提高该系统性能可靠性和实用性。【方法】基于高效水泵和研发的逆变器,构建了农田灌溉光伏水泵系统,结合系统装置构成与运行特点,对不同扬程运行工况下的电性能参数和扬水效率特性及... 【目的】探究农田灌溉光伏水泵系统综合用能需求特性,提高该系统性能可靠性和实用性。【方法】基于高效水泵和研发的逆变器,构建了农田灌溉光伏水泵系统,结合系统装置构成与运行特点,对不同扬程运行工况下的电性能参数和扬水效率特性及水泵流量与功率特性等进行测试分析。【结果】在一定太阳辐射强度范围内,调速运行的水泵流量与输出频率有较好一致性;稳定运行时段的水泵流量可达到2 m^(3)·h^(-1);定扬程24.8 m下,系统最大扬水效率达12.7%,日平均扬水效率11.6%,日扬水量13.1 m^(3);当扬程降低到14.0 m时,最大扬水效率和日平均效率分别比前者低3.2%和3.6%,表明减低扬程并不一定能提高系统扬水效率,但对输出流量有影响。【结论】该农田灌溉光伏水泵系统配置稳态和动态性能良好,扬水能力可满足省水微灌和植被绿化等基本农业生产需要。 展开更多
关键词 农田灌溉 光伏水泵系统 扬程 流量 逆变器 最大功率点跟踪
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耕地保护田长制的政策工具谱系模型与政策启示——基于扎根理论的政策文本实证分析
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作者 方印 李杰 佀耀耀 《中国土地科学》 CSCD 北大核心 2024年第1期94-104,共11页
研究目的:分析各省市相继出台的耕地保护田长制实施(工作)方案,描绘其政策工具全貌及其使用特征,为政策完善与优化提供参考。研究方法:扎根理论,内容分析法。研究结果:(1)耕地保护田长制的政策工具谱系模型为“四维驱动式凌锥模型”,该... 研究目的:分析各省市相继出台的耕地保护田长制实施(工作)方案,描绘其政策工具全貌及其使用特征,为政策完善与优化提供参考。研究方法:扎根理论,内容分析法。研究结果:(1)耕地保护田长制的政策工具谱系模型为“四维驱动式凌锥模型”,该模型由目标导向型政策工具、系统变革型政策工具、过程控制型政策工具、能力建设型政策工具耦合而成;(2)“注意力分配—职权责明晰—有序化运作—积极性调动”是耕地保护田长制的政策工具使用逻辑,立足此逻辑有助于畅通耕地保护“最后一公里”;(3)当前耕地保护田长制在政策工具使用上存在组合结构不合理、可操作性不强、创新性不足、实质效力不高等问题。研究结论:未来应协调政策工具使用比例,优化组合结构的适配性;细化政策工具操作流程,增强内容要素的精准性;注重政策工具创新变革,培育内生动力的发展性;提升政策工具效力层级,夯实功能发挥的有效性。 展开更多
关键词 耕地保护 田长制 地方政府 政策工具 扎根理论
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农田灌溉排水机械系统设计与性能分析
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作者 孙先明 《农机使用与维修》 2024年第6期21-23,共3页
灌溉与排水是调节农田水分供给的有效手段,是促进农作物良好生长的前提,为解决传统灌溉模式用水量大、水资源浪费、有效利用率低的问题,以及优化农田抗涝排水性能,针对农田灌溉排水机械系统进行优化分析与功能升级,分析了现阶段的灌溉... 灌溉与排水是调节农田水分供给的有效手段,是促进农作物良好生长的前提,为解决传统灌溉模式用水量大、水资源浪费、有效利用率低的问题,以及优化农田抗涝排水性能,针对农田灌溉排水机械系统进行优化分析与功能升级,分析了现阶段的灌溉排水机械应用情况与典型不足,对排水机械、灌溉机械的设备及附属设施进行设计和优化,并提供了性能分析参考建议,以期为农田合理用水提供参考借鉴。 展开更多
关键词 农田 灌溉机械 排水机械 系统设计 分析
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List of 85 typical catastrophic landslides from March 2004 to February 2024
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作者 Rui-chen Chen Yong-shuang Zhang 《China Geology》 CAS CSCD 2024年第2期369-370,共2页
Landslides are one of the most dangerous natural hazards that cause significant property damage and loss of life.Landslides often destroy farmland,villages,houses,factories,schools,roads and other facilities,injuring ... Landslides are one of the most dangerous natural hazards that cause significant property damage and loss of life.Landslides often destroy farmland,villages,houses,factories,schools,roads and other facilities,injuring humans and livestock.Sometimes,entire towns are devastated by landslides.Due to their pervasiveness,varied triggering factors,and sudden occurrence,landslides are currently one of the most challenging natural disasters to prevent and mitigate. 展开更多
关键词 stated farmland CATASTROPHIC
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