Technical Standards for Lotus Root-Redswamp Crayfish Integrated Farming

Lotus root-redswamp crayfish integrated farming is a kind of ecologicalgrow mode on the basis of paddy field, which is an innovated mode for agricultural structure adjustment and special agriculture with high efficiency. In order to regulate producing technology of this mode, the essay puts forward some technical require- ments, stressing on cultivar selection, field works, farming technology and product quality, which aims at providing technical support for agricultural production.

Research Progress of Rice-Fish Integrated Farming

Rice-fish integrated farming （RFIF） can change the agricultural production pattern from mono-farming model to the co-farming model, and the stereoscopic and integrated farming system established by RFIF can change the flat production to the stereoscopic production. Therefore, RFIF is the important development direction for agriculture to change pattern and adjust structure. In order to further promote development of the research and application of RFIF, the general development situation of RFIF in China was reviewed; the effects of RFIF on increasing farmer income and enhancing agricultural efficiency were clarified. The technologies matched with RFIF, such as rice paddy engineering technology, safe plant protection technology, security fertilization technology, fish disease prevention and control technology and water quality management technology, were summarized, and the supporting role of RFIF for agriculture was pointed out. In addition, the development prospect of RFIF was proposed, as well as the key research direction of RFIF.

Development of an Integrated Tool for Small-Scale Maize Farming in Uganda

About 62% of the maize produced in developing countries is cultivated manually owing to limited access to appropriate technology. Available technologies perform a single operation, necessitating farmers to buy multiple implements, which is expensive. In this study, an ox-drawn tool integrating a plough, planter and cultivator for small-scale maize farming was developed and its performance evaluated. Planting and cultivating units were designed and fabricated for assembly onto an existing standard ox-plough beam. The integrated tool was tested in the field to assess the effectiveness and efficiency of cultivation and planting of maize. Results showed that the planting unit had an average seed rate of 35.4 kg/ha with a seed damage of 4% and an effective field capacity of 0.15 ha/h at a field efficiency of 87.3%. The cultivating unit had an effective field capacity of 0.1 ha/h and a weeding efficiency of 86%. The efficiency, effectiveness and reliability for field operations are superior to manual operations currently used by farmers and are comparable to single-unit prototypes developed in other countries. This demonstrates the technical feasibility of integrating planting and cultivation units onto an existing mould board plough instead of buying multiple tools.

Transient Stability Study of Power System with Large-Scale Wind Farm Integration

Large-scale wind power integration has become the current development trend of the power system. Large-scale wind power integration can change the original structure and characteristics of the system. Thus, it’s necessary to analyse the transient stability of power system which contains wind power, and to study the controlling strategy for improving the transient stability of power system. Based on EEAC, this paper studies the transient stability of the power system which contains wind power system theoretically, proposes the calculation method for accelerating area, decelerating area and margin, and illustrates the impact of wind power integration on the transient stability with power angle curve. Furthermore, this paper studies the modeling and simulation, and the experimental results prove the correctness of the theories.

Empirical Study on the Benefit Increase of New Contract Farming 1+3+X Model

For a long time,the development model of traditional rice planting industry has been single,linear,and focusing on production first and then market.However,with the low price of rice,such problems as slow technological upgrading,meager profits,and unstable rice quality in the primary industry planting units and farmers have become increasingly prominent.The integration and development of the rural primary,secondary,and tertiary industries and industrial integration have the same root.They are integrated industrial development based on technological or model innovation,vertical and horizontal integration.Three agricultural leading companies(Nanjing Tianwei Agricultural Technology Co.,Ltd.,Nanjing CHYKINGYOUNG Biological Technology Co.,Ltd.,and Jiangsu Jingshan Eco-organic Agriculture Co.,Ltd.)established an industrialization complex,and used their respective technical,operational,and market advantages to integrate and form a rice contract farming 1+3+X model.This model effectively integrates scattered rice planting,rice processing,and rice sales in Nanjing City of Jiangsu Province,and Chuzhou City of Anhui Province,and unifies planting regulations and supply of production materials,safeguards the supply of green and high-quality rice and realizes high quality and high price.In addition,it integrates farmers into the entire industrial chain of contract farming,summons up the production enthusiasm of farmers and greatly increases their income from planting production.

风电场参与电网调频的多机协同控制策略

【目的】考虑风电场中不同风况下风电机组参与一次调频能力的差异,在下垂控制和惯量控制策略的基础上,对机组的调频能力评估方法进行优化。【方法】提出了一种改进的多机组调频参考功率协同控制策略。【结果】引入多机组协同控制方法能够有效改善机组之间调频参考功率的分配,从而有效调节各机组参与系统一次调频的程度。在惯量控制和下垂控制的基础上引入改进的协同控制策略,依据机组在实际风况下运行的状态,评估机组能够有效参与一次调频的参考功率。引入调频能力系数能够实现调频功率参考值在各机组之间按能分配。【结论】协同控制策略能够有效保护风电机组转速,同时能够有效改善电网频率响应。

乡村振兴背景下栽培与耕作学教学改革与探索

栽培与耕作学是涉农专业的核心课程之一,在乡村振兴背景下,其对农业人才的培养具有重要作用。该文以贵州师范学院为例,对栽培与耕作学课程的历史沿革进行介绍,对课程教学现状以及存在的问题进行探讨分析,从课程思政、课程内容、教学评价和教学方法等方面提出一些建议,以期为高质量课程的建设提供参考。

稻虾共作稻田浮游植物群落格局及环境影响因子

为了解稻虾共作稻田浮游植物群落结构特征,对安徽省肥西县和全椒县国家级稻渔综合种养区稻田浮游植物进行了养殖前期、中期、后期三次调查,并探讨了其与环境因子的关系。结果表明,肥西、全椒分别观察到浮游植物6门55种、7门61种,两地的优势类群均为绿藻门和硅藻门。肥西、全椒浮游植物平均密度分别为3.50×10^(6)ind./L和7.90×10^(6)ind./L,平均生物量分别为1.49 mg/L和2.55 mg/L。对Margalef丰富度指数(D)、Shannon-Wiener多样性指数(H′)和Pielou均匀度指数(J)的分析表明:肥西三个养殖时期的D无显著差异,而H′和J均有显著差异;全椒三个养殖时期的H′、D和J均无显著差异。典型对应分析(CCA)表明:溶氧、pH、水温、叶绿素a是与肥西浮游植物群落结构相关性较强的环境因子;冗余分析(RDA)表明:总磷、高锰酸盐指数、pH、氨氮是与全椒浮游植物群落结构相关性较强的环境因子。浮游植物密度结果表明,两地稻田前期和中期水质为中营养状态,后期为富营养状态。

关于农耕文化赋能乡村产业融合发展的几点思考

农耕文化泛指与农耕生产相关的综合性的知识形态和文化表征,其最直接的表现形式是重要农业文化遗产和乡村非物质文化遗产,因其显著的地域性、意义和价值的多层面性以及低成本的可叠加性等特征而具有强大的使能性,是赋能乡村产业融合发展的重要资源和有力杠杆。乡村产业融合发展面临同质化竞争等严峻挑战,亟需发挥农耕文化的赋能作用。农耕文化赋能乡村产业融合发展的行动策略可以概括为三大步骤,即“普查”“链接”和“激活”。通过对农耕文化的“普查”并将其与现代生活和乡村产业发展相“链接”,有助于“激活”农耕文化和农业农村资源的巨大潜能,让历史悠久的农耕文化在新时代展现其魅力和风采,进而赋能乡村农工文旅产业融合创新,整体推动农业农村新质生产力发展。

家庭农场创业资源整合驱动因素与作用机理研究——基于扎根理论和SEM模型的融合方法

我国现有家庭农场尚处于起步阶段,因受自身弱质性、创业资源匮乏、创业环境复杂性等因素制约而面临着巨大挑战。文章基于相关文献将家庭农场创业资源整合过程界定为识别、获取、配置和运用,使用扎根理论方法分析30个家庭农场资源整合案例,形成创业资源、内在需求、整合意愿、农场主个性特征、创业环境和家庭农场创业资源整合6个维度理论构想,建立驱动因素模型。依据分析结果,借鉴相关测量量表开发创业资源整合驱动因素量表,验证量表信效度并利用结构方程模型对建构的理论模型进行实证检验。结果表明,创业资源和整合意愿直接驱动家庭农场进行创业资源整合,内在需求经由整合意愿驱动家庭农场进行创业资源整合,农场主个性特征和创业环境在内在需求与整合意愿关系中起调节作用。通过拓宽创业资源整合的研究外延,丰富家庭农场创业问题的理论与方法体系,为家庭农场破解资源约束困境提供了新思路。

基于改进的随机森林—模糊积分模型的家庭农牧场信用评级研究

缓解融资难融资贵问题是实现家庭农牧场可持续发展的关键,而构建家庭农牧场信用评级体系是解决该难题的基础。针对家庭农牧场信用风险评估中样本数据指标多、噪声复杂、非线性乃至高维度等问题,以内蒙古自治区12个盟市500个家庭农牧场为信用评价对象,将XGBoost算法、随机森林算法、模糊积分模型进行组合,构建了改进的随机森林—模糊积分模型,对家庭农牧场进行信用评级。分析结果表明:运用改进的随机森林—模糊积分模型对家庭农牧场进行信用评级的准确率、精确率、召回率、F1分数更高。

山区农产品主产区种养关联碳减排潜力估算——以四川洪雅、开江、盐亭和兴文县为例

种养关联既可有效利用农业废弃物,又具碳减排效应。已有研究主要聚焦农业废弃物资源化利用及其污染控制,对农业种养关联碳减排缺乏关注。本文以四川盆地山地丘陵农产品主产区的洪雅、开江、盐亭和兴文4县为研究对象,采用草谷比法估算作物秸秆量,依据能量转化构建秸秆饲料化利用碳减排潜力估算法,采用排泄系数法估算畜禽粪便量,依据营养物质循环构建粪便肥料化利用碳减排潜力估算法,探讨2008—2017年该区种养关联碳减排潜力。结果表明:(1)该区种养关联年均碳减排潜力为19.42×10^(4)t,且微弱上升(1.25%)。其中,作物秸秆饲料化利用年均碳减排潜力15.49×10^(4)t,上升8.37%;畜禽粪便肥料化利用年均碳减排潜力3.93×10^(4)t,下降23.09%。(2)该区单位耕地面积种养关联碳减排潜力为2.04 t/hm^(2),其中,开江(2.36 t/hm^(2))>洪雅(2.30 t/hm^(2))>盐亭(2.01 t/hm^(2))>兴文(1.57 t/hm^(2))。(3)该区种养关联碳减排潜力中作物秸秆饲料化利用占比(79.75%)>畜禽粪便肥料化利用(20.25%);作物秸秆饲料化利用碳减排潜力以水稻(35.07%)、玉米(24.99%)、小麦(13.44%)和油菜(12.77%)等作物为主(共86.27%);畜禽粪便肥料化利用碳减排潜力以牛粪便为主(占52.94%)。本研究可以为山地丘陵区种养关联碳减排提供理论依据。

面向乡村振兴的农业技术应用与推广型人才培养体系构建与实践--以山东农业大学为例

全面推进乡村振兴,实现农业农村现代化,关键在科技、在人才。山东农业大学构建的农业技术应用与推广型人才培养体系,在人才培养实践中坚持“学生中心、需求导向、协同育人”培养理念,采用厚植情怀、耕读合一和协同育人等人才培养路径,创建“四课融通、‘四层次’实践、三位导师、三联合”育人模式。经过五年实践,培养一批“下得去、用得上、留得住、干得好”的农业技术应用与推广型人才,在破解乡村振兴人才瓶颈问题方面呈现出良好的发展局面。

长江流域2种水产养殖模式的生命周期环境影响评价

本研究以长江流域内的池塘养殖和稻渔综合种养2种水产养殖模式为对象,应用生命周期评价方法,分析2种养殖模式对能源消耗(EU)、全球变暖潜势(GWP)、酸化潜势(AP)、富营养化潜势(EP)以及水资源消耗(WU)5种环境指标的影响,并探究2种主要输入因子(饲料和电力供应)和养殖过程对各环境指标的影响,从而评价2种养殖模式对环境影响的差异。生命周期评价结果标准化处理和加权评估显示,稻渔综合种养模式的WU、EP、GWP、AP和EU值分别为11.650、0.770、0.141、0.096和0.003,总环境影响指数(TEII)为12.660;池塘养殖模式的WU、EP、GWP、AP和EU值分别为31.453、1.187、0.210、0.174和0.007,TEII为33.031。与稻渔综合种养模式相比,池塘养殖模式的各项环境指标均较高。对环境影响的贡献率分析表明,饲料供应对EU、GWP和AP的贡献率最高,EP主要受饲料供应和养殖过程的共同影响,而WU主要集中在养殖过程中,电力供应主要影响EU、GWP和AP。生命周期评价的结果表明,与池塘养殖模式相比,稻渔综合种养模式显示出更友好的环境效益,在我国长江流域具有较大的发展空间。2种养殖模式的贡献率分析表明,改进饲料生产工艺、建立精准投喂技术、应用先进的尾水处理技术和适当提高养殖密度是我国长江流域水产养殖环境友好生产的关键。

大豆—玉米带状复合种植耕种机械化研究进展

为充分发挥大豆—玉米带状复合立体化种植技术优势,保证我国粮油安全,解决作物争地矛盾,配套的复合耕种机械化研究成为首要环节。从国内典型多种植模式出发,总结地区间套作技术下大豆—玉米配套耕种机械特点,围绕耕种机具整地、洁茬、施肥、排种、播深及投种等作业阶段,阐述对比耕种机械技术工作原理,发现实际生产中仍存在秸秆拥堵、种肥排量和位置不协同、播深变异系数大和投种着床不均匀等问题,从农机农艺融合方面提出轻扰低耗洁茬、处方分层施肥、种肥电驱变量控制、多传感智能仿形播种、种粒平稳着床等一系列改良大豆—玉米复合耕种机械的路径,以期促进绿色高效发展。

生态种养技术采纳能否提升农户社会资本?——以稻虾生态种养技术为例

生态种养技术的经济和生态功能一直备受关注,但社会功能却一定程度上被忽视。为探究生态种养技术的社会功能,本文基于湖北省江汉平原地区1039份稻虾生态种养农户的调研数据,采用处理效应模型,分析并检验了生态种养技术采纳行为对农户社会资本水平的提升作用。结果表明:1)稻虾生态种养技术的社会功能十分突出,稻虾生态种养技术采纳行为对农户社会资本存在显著的提升效应。农户采纳稻虾生态种养技术后社会资本总量水平会提升0.047个单位,其中社会网络规模将扩大114.266个单位,而社会网络地位则降低了3.595个单位。2)从影响机制来看,合作社参与和互联网使用是稻虾生态种养技术采纳行为提升农户社会资本的重要途径。3)从异质性分析来看,稻虾生态种养技术采纳行为对农户社会资本的提升效应存在收入和年龄异质性,稻虾生态种养技术采纳行为对高收入和60岁以下农户的社会资本提升效应更为明显。因此,要全面地认识和客观地评价稻虾生态种养技术的社会功能,进而促进农户社会资本积累。

农旅融合、要素流动与县域经济增长

农旅融合是践行“绿水青山就是金山银山”理念的良好载体和生动实践。在理论分析和模型推演的基础上,利用休闲农业与乡村旅游示范县政策设计准自然实验,并基于2008-2019年中国1778个县域的面板数据,采用多时点双重差分模型,考察农旅融合发展对县域经济增长的影响。结果表明,农旅融合发展对县域经济增长具有显著的推动作用。该结论在经过平行趋势检验、反事实检验等多重稳健性检验后依旧成立。机制分析表明,农旅融合发展主要是通过吸引资本流入、加快非农转移和推动技术进步来提高县域经济发展水平,进一步凸显出要素流动在县域经济增长过程中的传导作用。此外,从资源禀赋看,农旅融合经济增长效应的发挥,不仅依赖于县域内部旅游生态资源,对外部交通条件等基础设施也有较高要求。同时,东部地区县域的农旅融合发展能发挥出更明显的经济增长效应。可见,基于本地资源优势推进农旅融合发展,并进一步补齐县域交通等基础设施建设短板,是推动县域经济增长的重要选项。

漂浮式风电技术现状及中国深远海风电开发前景展望

随着海上风电高速发展及近海场址资源趋紧,适用于深远海域风资源利用的海上漂浮式风电成为中国海上风电未来发展方向。本文介绍国外和国内漂浮式风电发展历程与现状,详细阐述了漂浮式风电从样机示范、小型漂浮式风电场到大规模商业化开发的发展路径,分析不同漂浮式风电基础概念及其特点。剖析了中国漂浮式风电本土化发展所需要面临的技术挑战,主要包括大容量漂浮式风力发电机组、低成本漂浮式风电基础平台、新型系泊系统国产化研制、动态缆系统研制、高效建造安装施工模式和智慧运维安全保障等。针对中国独有的海洋环境、港口码头状况和风电产业链情况,提出了海上漂浮式风电研究方向和发展建议:研发设计适用于中国深远海抗台型大容量漂浮式风电,突破漂浮式风电降本平价发展瓶颈;考虑高效集约用海布局,规模化发展漂浮式风电场;强健漂浮式风电产业完整供应链,推进核心部件和设备国产化进程;创新“海上风电+”新模式新路径,探索海上风电与油气田多能互补融合发展。本文研究对海上漂浮式风电平价商业化开发和扩展海洋能源利用空间具有重要意义。

基于模型数据混合驱动的大规模双馈风电场并网数字孪生建模

当前双馈风机详细模型具有多时间尺度动态和复杂控制环节,导致建模困难、大规模双馈风电场并网详细仿真建模所需算力庞大的问题。实际风机并网外特性无法实时反馈到仿真系统中,同时风电场功率输出受到多方面如风速、风向、老化等影响,使仿真系统无法精确拟合真实电力系统。针对这一问题,该文构建大规模数字孪生双馈风电场并网的电力系统模数混合驱动模型,实现了风机与电网互动反馈的实时更新,降低了算力需求,同时与风机物理实体实时匹配的虚拟模型具备较高的输出精度,满足精细化仿真需求。文中每台双馈风机采用长短期记忆网络构建数据驱动模型,风电场架构及所并电网选取常用的物理仿真模型,以数字孪生技术实现风机物理模型维护、虚拟数据模型更新的双向反馈。算例通过真实量测数据测试,结果表明在不同工况下该双馈风电场并网数字孪生模型较传统模型具备更优秀的拟合能力与精准度,同时实现了虚拟模型的实时更新能力。该模型有助于在大规模风电场并网中探寻具体某台风机故障、控制方式变化、风速波动等情况,研究风机之间相互影响、电网出现扰动时对风电场的影响。

Study on Diversity of Arthropod Community in a Rice-duck Integrated Farming System in South China

The integration of ducks into rice farming has raised concerns about possible effects on arthropod communities due to frequent predation by ducks. This paper conducted a study using three treatments, including integrated rice-duck cultivation （RD）, conventional rice cultivation （CC） and a control treatment （CK）, to investigate the impact of rice-duck farming on the diversity of arthropod communities in the field. The results revealed that arthropod numbers in both RD and CC treatments showed varying degrees of reduction when compared with the CK treatment. Arthropod individual numbers, Simpson （D） and Shannon＇s diversity index （H＇） values in RD were higher than those in CC. Arthropod individual numbers, richness index （R）, D and H＇ values in both tillering and booting phases of the late rice were significantly higher in RD treatment than those in CC treatment. Rice-duck integration system was favorable for the maintenance of arthropod diversity in the cropping field and may help to lessen the decline in abundance and diversity of rice farmland arthropods caused by the utilization of chemical pesticides and fertilizers.