三峡茶区不同水质泡茶效果的研究

对6种不同水质水的理化性质和分别冲泡不同茶叶后茶叶香气、汤色、滋味的感官审评结果进行比较，同时比较茶汤中水浸出物和氨基酸的浸出量，发现水质对茶叶的色、香、味有很大影响，好水更能体现好茶的品质特征，次水泡茶效果较差。研究结果表明，6种水泡茶的优劣依次是：泉水、溪水、江水、池塘水、自来水、井水。     

TMV侵染烟草基因差异表达的cDNA-AFLP分析

以烤烟品种龙江925 [高抗烟草普通花叶病(TMV)]接种TMV的叶片为材料,选用240对引物组合的扩增, 获得约 9 500个转录基因片段, 经过克隆测序最终获得了12个诱导表达片段, 它们与核酸代谢、蛋白质合成与修饰、能量代谢、胁迫响应、细胞内运输、糖代谢等相关, 并利用荧光定量PCR分析一个诱导表达片段TIF2在0~72 h之间5个时间点(0、12、24、48和72 h)的基因差异表达, 证实了所获得的基因序列为真实诱导的表达序列。对此序列进行RACE, 最终获得全长cDNA序列, 全序列857 bp, 预测的编码区在101~613 bp之间, 共编码170个氨基酸。经Blastn、Blastp比对分析, 在烟草中没有获得其同源序列, 确定该基因是在烟草中发现的与抗TMV相关的新基因。     

带状种植小麦带型—群体—产量相关规律的研究

本研究在高产田条件下, 选用中穗型冬小麦品种泰876161, 在留有70 cm间套行条件下, 研究了带状种植小麦的带型—群体—产量相关规律。 主要结果是： (1) 带状小麦同常规方式, 在精量播种下获得高产。 大播量、 大群体栽培减产。 (2) 带状小麦实播面积下降, 最优群体产量较常规方式最优产量减产。 带型愈窄, 实播面积愈     

内蒙古地区双峰驼生活习性的研究

作为优秀的家畜物种双峰驼的数量越来越少了,在世界范围内主要分布在中国和蒙古人民共和国等国家。其中中国骆驼总数居世界第2位,而内蒙古地区双峰骆驼的数量又占到全国总数的60%以上。骆驼是生活在荒漠和半荒漠的重要畜种,在长期的进化过程中机体构造、器官功能和生活习性形成了许多特性,以适应独特的荒漠条件,因此被誉为"沙漠之舟"。骆驼是一种宝贵的畜种资源,对其遗传资源的保护应该受到足够的重视。同时,驼肉纤维较粗,脂肪含量少,瘦肉多,驼乳脂肪球小,易被人体消化吸收,属于"绿色食品",适合于当今人们追求的饮食需求;驼绒是上等的毛纤维,是毛纺工业的重要原料之一,市场前景非常广阔。通过野外考察、定位观测和原地实验等方法,系统地论述了内蒙古地区双峰驼的形态特征和生活习性,以期引起人们对这一物种的重视。     

基于能值的顺德市农业系统生态经济动态

以能值理论方法为主要手段结合环境经济学方法，以顺德市农业系统改革开放22年的发展动态为研究对像，从成本价值结构和产出效应价值两个角度，开展城市化过程中城市农业系统生态经济动态的分析与评价研究，探索能值方法与环境经济学方法的整合路径。提出能值投入产出平衡计算的算法和能值效益率(EBR)、能值本地影响率(LCR)等一系列生态经济评价指标。结果表明，顺德农业系统生产率高于全球平均水平，但资源型农产品能值交换率长期小于1，系统在繁荣的市场交易中处于实际的亏损地位，建议针对猪肉和鱼类这两种主要产品，增设相应的深加工环节。能值分析方法和环境经济学方法有着较好的互补性和一致性，但在具体指标体系选择与构建及产出端分支的量化上还有待进一步完善。     

Reduction of N-Nitrosodimethylamine (NDMA) in Aqueous Solution by Nanoscale Fe/Al2(SO4)3

A novel immobilized visible light-active photocatalyst (TiO₂/polyvinyl alcohol after thermal treatment (T-PVA)/cordierite honeycomb (CHC)) was successfully prepared by a simple and convenient method combining sol–gel and thermal treatment using tetrabutyl titanate (TBOT) as the titanium source, polyvinyl alcohol (PVA) as the precursor of conjugated polymer, and CHC as the support. The synthesized photocatalyst was characterized by X-ray diffraction, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, ultraviolet–visible diffuse reflectance spectroscopy, and field emission scanning electron microscopy. The results showed that PVA was dehydrated to produce conjugated unsaturated T-PVA. The T-PVA not only extended the response spectrum of TiO₂ to visible light region, but also strengthened the adhesion of TiO₂ to CHC. The TiO₂/T-PVA/CHC showed both outstanding adsorption properties and excellent photocatalytic performance under visible light on the decolorization of Rhodamine B. Over eight cycles, the photocatalyst continued to maintain perfect photocatalytic activity, showing good stability.

有机肥替代化肥比例对椪柑生长发育、产量和土壤生物学特性的影响

  【目的】  通过研究等氮磷钾养分条件下,有机肥替代化肥比例对椪柑生长、养分吸收、产量和土壤微生物性状的影响,提出适宜的有机替代比,为柑橘化肥减量与提质增效技术提供理论依据。  【方法】  于2019、2020年在重庆连续进行田间试验,供试材料为15年生枳砧台湾椪柑(Citrus reticulata Blanco cv. Ponkan)。设置CK (不施肥)、FP (单施化肥)、T1 (有机替代率为氮10%、磷25%、钾18%)、T2 (有机替代率为氮15%、磷38%、钾27%)、T3 (有机替代率氮20%、磷51%、钾36%)、T4 (有机替代率为氮30%、磷76%、钾54%)共6个处理,除CK外,各施肥处理的氮、磷、钾养分一致。调查分析椪柑生长、养分吸收、产量和肥料贡献率及土壤微生物特性。  【结果】  1)与FP相比,有机肥替代处理(T1至T4)增加了根系量、根系活力和枝梢生长量,显著增加了细根(直径0～0.5 mm)比例,且增加幅度随有机替代比的增大而提高;有机替代处理的春梢叶片SPAD、P_n、PI_abs和PI_total等较FP处理均有不同程度的提高,并随有机替代比的增大呈先升后降的趋势;以T2和T3处理对椪柑生长发育较好;2) 2019和2020年有机肥替代处理的枝梢和果实N、P和K积累量相比FP有一定程度的增加,且随有机替代比的增加均呈先升后降的趋势;2019和2020年各有机肥替代处理较FP处理平均增产了7.2%～26.4%和2.0%～36.9%,肥料贡献率比FP处理分别提升了5.2%～45.4%和3.3%～54.9%,但随有机替代比的增加呈先升后降的趋势,以T2和T3处理促进养分积累和增产的效果较好;3)有机肥替代处理的根际土壤脲酶、蔗糖酶活性及可培养的细菌和放线菌数量较FP均有所增加,且随有机替代比的增大而增加,7月时达最大,而土壤可培养真菌数量表现出先增后减的趋势,以T3和T4处理对土壤微生物特性较好。  【结论】  等氮磷钾养分情况下,有机肥替代化肥促进了椪柑侧根根系特别是细根和春、秋枝梢的生长发育,改善了叶片的光合作用,提高了枝、叶、果对养分的积累和椪柑产量,改善了果园土壤生物学特性。本试验条件下,以有机替代15%～20%的氮肥、38%～51%的磷肥和27%～36%的钾肥的效果最好。     

柑橘园植保无人飞机低容量喷雾技术探索——以柑橘木虱和潜叶蛾防控为例

【目的】探索植保无人飞机(unmanned aerial vehicle,UAV)喷雾在柑橘冠层的雾滴沉积分布规律和无人机植保作业参数,并开展柑橘木虱(Diaphorina citri)和潜叶蛾(Phyllocnistis citrella)无人飞机防控实效研究,评估防治效果、作业效率和综合效益,为UAV低空低容量喷雾技术的建立和在柑橘产区的应用提供依据。【方法】在丰产期的鸡尾葡萄柚园,将4行约100株自然圆头形树冠修剪成开心形,另选4行自然圆头形树冠作为对照。在采样植株冠层内部搭设立体网格架,网格架垂直方向分上、中、下3层,每层设置3×5共计15个采样点,每株树共计45个观察点,每个点放置两张4 cm×6 cm铜版纸卡作为雾滴承接载体。以0.5%诱惑红水溶液作为示踪剂,六旋翼UAV分别在不同飞行作业速度(v₁=0.7 m·s^-1、v₂=1.2 m·s^-1、v₃=1.7 m·s^-1)和不同作业高度(h₁=1.0 m、h₂     

A real-time automated system for monitoring individual feed intake and body weight of group housed turkeys

Feed conversion is an important production trait in turkey breeding; the measurement of an individual bird's feed efficiency is important in identifying the most genetically superior individual. The development of a real-time automated feed intake and body weight monitoring system is described in this paper. The system integrated multiple feed and body weight weighing stations consisting of electronic scales, radio frequency identification (RFID) devices and data communication modules. A distributed and client-server-based system architecture with multi-threading software design was developed. This system architecture allowed for a real-time data acquisition capability when a large number of stations were required. A structured query language (SQL) database management system was developed to record and manage the dynamic feed intake and body weight gain data of individual birds. The developed system also offers a powerful research tool for studying poultry feeding behavior under group housing conditions.     

Reduced breeding success in white-tailed eagles at Smøla windfarm,western Norway,is caused by mortality and displacement

Climate change scenarios and efforts to reduce CO₂ emissions have increased the focus on wind power and other renewable energy sources. Despite producing “clean” electricity, windfarms do have impacts on the environment. We studied the impact from a coastal windfarm on the breeding success of white-tailed eagles (Haliaeetus albicilla) at Smøla, western Norway by means of a BACI (before–after–control–impact) approach. The objective was to compare pre- and post-construction breeding success. A 10 year dataset from 47 eagle territories were analyzed using a generalized linear mixed model. Successful breeding was used as a response variable, while distance to turbines, distance to roads and before/after turbine construction were used as predictors. There was a significant effect of the interaction between time period and distance to turbines, showing that territories within 500 m from the turbines in the post-construction period experienced significantly lower breeding success than the same territories before construction. We found that this effect was most likely due to territories being vacated. The results emphasize the importance of using a BACI approach when assessing possible effects from wind-power production on breeding birds, especially for species breeding at low densities. It also emphasizes the importance of conducting thorough pre-construction studies on vulnerable bird species.