生物炭对酸化茶园土壤性状和真菌群落结构的影响

为探讨生物炭长期施用对酸化茶园土壤改良和真菌群落结构的影响,分析了按生物炭用量0、2.5、5、10、20、40 t·hm^-2施用5年后的茶园土壤性状和真菌群落结构变化。结果表明,施用生物炭5年后的茶园土壤pH提高了0.16~1.11,可溶性有机碳含量提高了52.6%~92.3%,而铵态氮和硝态氮含量以10 t·hm^-2处理最高。施用生物炭5年后的土壤性质变化,进一步影响了真菌群落结构,表现为Chao指数、ACE指数和Shannon指数随生物炭用量增加呈先增加后降低的趋势;提高生物炭施用量对茶园土壤次要作用的真菌（LDA值<3.50）丰度的增加效果高于优势真菌（LDA值>3.50）的效果,其中被孢霉属、木霉属、毛壳菌属的相对丰度增加,黑盘孢属的相对丰度降低。     

设施畜牧业关键技术研究态势分析

[目的/意义]目前中国畜牧业正处于加快转型的重要时期,了解相关技术的发展态势对于畜牧业的发展具有一定的借鉴意义。[方法/过程]本文以设施畜牧业领域技术研发的3个主要方向：笼舍技术、饲喂饮水技术和环境控制技术的相关专利为研究对象,利用专利计量的方法对其发展趋势、技术分支、申请人、各阶段重点专利等进行了分析。[结果/结论]笼舍、饲喂饮水和环境控制技术发展同步经历了萌芽期、波动发展期、快速发展期3个阶段,当前申请量呈现直线上升的态势;技术研发主体以企业为主,各研发单位之间技术布局差异性明显;近些年重点专利中的国内专利明显增多;笼舍技术方面装置研发均侧重于粪尿清除、垫板等技术;饲喂饮水技术方面饲喂技术的研究多于饮水技术,且均侧重于研发自动化设备;环境控制技术侧重于废弃物处理技术、空气调节技术和房舍清洁刷洗技术。     

Soil quality assessments in integrated crop–livestock–forest systems: A review

Integrated crop–livestock–forest is a promising strategy to improve soil quality. It comprises four different integrated farming systems: crop–livestock, crop–forest, forest–livestock and crop–livestock–forest. This work systematically reviewed studies about integrated crop–livestock–forest systems and soil quality. A total of 92 papers were retrieved from the Web of Science—Clarivate Analytics platform, and the following information was analysed: publication year, institution, region of the studied site, type of integrated system, soil type, tillage system, maximum soil depth and the soil quality indicators assessed. Most studies were published in the second half of the 2010s. Brazil is a prominent focus of research about soil quality and integrated crop–livestock–forest systems, with significant contribution from its central and southern regions. The Embrapa was the main publishing institution, present in over one‐third of the studies. Crop–livestock was the most common integrated system, Ferralsols was the most common soil group, and most of the studied soils were clayey. No tillage was the main tillage system. Most studies focused on the topsoil, assessing physical and/or chemical soil quality indicators. More emphasis on biological indicators of soil quality is required, as well as assessments integrating biological, physical and chemical indicators of soil quality. Future works should compare different integrated systems, including assessments deeper in the soil profile, especially in systems with the forest component, and also in sandy and silty soils. Soil quality indicators that have been rarely used should be further tested. Novel indicators should be added to better understand the promotion of soil quality by integrated crop–livestock–forest systems.     

有机肥对土壤特性及农产品产量和品质影响研究进展

施用有机肥是农业生产的重要措施,对绿色农业发展起到积极作用,而且越来越广泛施用。本文介绍了目前有机肥基本概况,重点综述了有机肥对提高土壤肥力、提高作物产量和品质、促进养分利用以及对病虫害发生影响等方面研究的最新进展,分析了当前有机肥施用对耕地质量和农产品安全风险、施肥效率低、以及有机肥品种研发不足、相关质量标准滞后等问题,并对当前有机肥推广应用的形势和发展前景进行了分析和展望。     

茶园节能型开沟刀设计与试验

针对茶园机械化开沟减阻减耗需要,设计茶园节能型开沟刀,用于减小茶园开沟时的开沟功耗。通过理论分析确定节能型开沟刀侧切刃与正切刃曲线方程,通过离散元仿真方法确定侧切刃螺旋线终点处滑切角与正切刃在侧切刃平面内展开曲线终点处静态滑切角分别为62°、56°。对设计完成的节能型开沟刀进行田间试验,试验结果表明:在开沟深度为15、20、25 cm时,节能型开沟刀的开沟功耗分别为0.093、0.107、0.128 kW,均小于对照组通用开沟刀的开沟功耗,说明设计的节能型开沟刀在各个开沟深度均能够达到降低开沟功耗的目的。此外节能型开沟刀在不同开沟深度的沟深稳定性系数均大于90%,高于国家标准和对照组通用开沟刀试验结果,说明设计的节能型开沟刀在降低作业功耗的同时,可保证开沟质量。     

Nutrients in litterfall,forest floor and mineral soils in two adjacent forest ecosystems in Greece

The fluxes of masses and the nutrients Ca,Mg,K,N,P and S were determined in the litterfall of two adjacent forest ecosystems of Hungarian oak(Quercus frainetto L.)and European beech(Fagus sylvatica L.)in a mountainous area of northeastern Greece in 2010–2015.The foliar litterfall for both species reached about 70%of the total litterfall,and was significantly higher from the other two fractions(woody and rest litterfall).The fluxes of masses and nutrients were compared between ecosystems for each fraction separately.Only one significant statistical difference was found,that of K in the woody litterfall.In addition,the stocks of masses and nutrients were calculated in the forest floors and mineral soils of the two ecosystems.Likewise,the stocks of nutrients in the forest floors and mineral soils were compared between ecosystems.In the L horizon of the forest floors,statistical differences,as a result of species effect,were found for the stocks of Ca and N.In the FH horizons,the masses and all the nutrient stocks differed significantly,as the beech plot had much higher quantities of organic matter and nutrients.These higher quantities were probably due to low soil temperatures(microclimate)and high acidity in the beech plot(species effect)that slowed down decomposition.In the mineral soils,the propagation of random error derived from random errors of the individual soil layers was an important factor in the statistical comparisons.Because of the soil acidity in the beech plot,the stocks of exchangeable base cations were significantly higher in the oak plot,whereas the other nutrient stocks did not differ.     

正交设计优化青蒿SRAP-PCR反应体系及引物筛选

为了建立青蒿的SRAP最佳扩增体系,并筛选出SRAP多态性引物,本研究以青蒿叶片DNA为模板,采用正交试验设计,以Mg^2+、dNTP Mix、Taq DNA聚合酶、引物和DNA模板5种因素5个水平,对青蒿SRAP反应体系进行研究。结果表明,青蒿SRAP-PCR最佳反应体系为:引物0.6μmol/L、Mg^2+2.0 mmol/L、模板DNA 5.1 ng、Taq DNA聚合酶2.0 U、dNTPs 0.25 mmol/L,总体积为25μL。各因素对扩增反应均有不同影响,其中引物浓度的影响最大,dNTPs的影响最小。运用该体系对不同种质资源的青蒿进行验证,证明该体系稳定可靠,并在30个引物组合中筛选出了25对扩增条带清晰,多态性丰富的引物组合。这一结论为今后利用SRAP标记技术进行青蒿分子遗传学研究提供了科学依据。     

热风干燥过程中山药水分状态的变化研究

为了解山药的水分赋存状态的变化，以襄阳道地山药为材料，分别在60、70、80、90、100 ℃条件下进行热风干燥，采用低场核磁共振（LF-NMR）和差式量热扫描（DSC）技术，每隔15 min测定山药在热风干燥过程中的水分状态及迁移规律。结果表明，在60~90 ℃条件下，温度越高，干基含水率的降速越快。山药的T2弛豫图谱有3个较为明显的吸收峰，随干燥进程的延续，各峰面积均明显减少，其中自由水所在峰的面积降幅最大，表明干燥过程中自由水散失最多，而且自由水逐渐向半结合水和结合水迁移，冷冻峰和解冻峰也随之变小。但在100 ℃下干燥时，样品可能因表面板结导致干基含水率、低场核磁吸收峰升高，冷冻和解冻峰面积增加。因此，在实际干燥过程中，山药的热风干燥温度不宜高至100 ℃。     

黄瓜病虫害绿色防控技术及示范成效

黄瓜病虫害种类多、危害大,传统用药方式严重影响产品质量和口感。为了保证直供上海的黄瓜达到无公害要求,对生产基地采取农业防治、生态控制、生物防治和物理防治相结合的绿色防控措施,化学农药使用量减少30%,综合防治效果在85%以上,有效减少了防治次数,降低了农产品的农药残留,667 m~2增产600 kg,增值600元左右。收到了较好的经济、生态及社会效益。