Spatio-temporal factors influencing the occurrence of Syngamus trachea within release pens in the South West of England     

《Veterinary parasitology》2015,207(1-2):64-71

Syngamus trachea is a pathogenic tracheal nematode that causes syngamiasis in wild and game birds, especially when birds are managed at high densities. Despite its pathogenic nature, very little is known about its epidemiology and relationship with ambient temperature and humidity. The spatial and temporal modelling of disease was undertaken on two pheasant estates within the South West of England from April 2014 to August 2014. Significant differences between the mean numbers of eggs per gram of soil were identified between pens at both site 1 and site 2 but did not differ significantly between sites. Egg abundance was significantly associated with soil moisture content, with greater egg survival between years in pens with higher average volumetric soil moisture content. Previous years stocking density and pen age were also associated with greater egg survival between years with more eggs being recovered in pens with greater stocking densities, and pens that had been sited longer. The greatest model to explain the variation in the numbers of eggs per gram of soil per pen was a combination of soil moisture content, stocking density and pen age.Larval recovery differed significantly between sites. Larval abundance was significantly and positively associated with temperature and relative humidity at site 1. Similarly, temperature and humidity were also positively and significantly associated with larval abundance at site 2. Rainfall did not influence larval recovery at either site 1 or site 2. The model with the greatest ability to explain larval abundance at both sites, was a combination of temperature, humidity and rainfall. Infection status (positive faecal egg counts) was significantly and positively associated with larval abundance at both sites, but rainfall was only positively associated at site 1. Temperature and humidity were positively associated with infection status at site 2, but not at site 1. The present study highlights the influence of climatic variables on both egg survival and larval abundance, and could therefore be used to develop more targeted treatment strategies around periods of higher disease risk. The frequent use of release pens is a clear factor in the epidemiology of syngamiasis, and it is recommended that pens be rested and/or rotated in order to reduce infection pressure in subsequent flocks.  相似文献   

遮雨棚设施结构对枣园温湿度的影响     

杨飞 《山西林业科技》2013,(3):23-25,43

笔者以7年生-10年生壶瓶枣树为试材，研究了遮雨棚栽培与大田栽培条件下温湿度变化规律和差异。结果表明：遮雨棚在晴天高温时有降温的作用，而阴雨天温度较低时则有保温的作用；遮雨棚阻碍了水分蒸发，使得相同条件下棚内湿度高于棚外；雨后棚内与棚外温度变化趋势基本一致，棚外湿度变化剧烈，棚内较为缓和。  相似文献   

单栋塑料温室内多因子综合CFD稳态模拟分析   总被引：1，自引：0，他引：1  

郝飞麟  沈明卫  何勇  冯雷 《农业机械学报》2014,45(9):297-304

为分析单栋塑料温室内的综合环境:气流场、温度场、湿度场、CO2浓度场,建立了包括温室内外空间、室内作物和土壤层等的温室环境几何模型。将温室内的湿空气看作水蒸气、CO2和干空气的混合气体,在分析温室中太阳辐射、作物与环境的质热交换,动量及质能传递过程的基础上,对单栋塑料温室内的环境因子进行了稳态模拟。温室内热辐射传递过程采用蒙特卡罗法模拟方法;将室内作物简化为连续固体换热模型,采用剪应力输运模型(SST)表述温室内的空气紊流。结果显示:温室通风对温度、湿度和CO2分布的影响很大,温室内部上风向温度低,湿度小,同时CO2浓度也不高;温室下风向作物冠层的环境未达到优化状态;模型的预测值低于实测值,但变化规律相似,温度、湿度、CO2含量的预测相对误差分别低于8%、6%和7%。  相似文献   

温室温度和湿度的多变量模糊控制技术   总被引：18，自引：1，他引：18  

钟应善  杨家强  邓劲莲 《农业机械学报》2001,32(3):75-78

介绍了一种基于MCS－51单片处理机的模糊控制温室温度的湿度技术，设计了模糊控制系统，并阐述了模糊控制系统的原理、方法以及硬件的组成。对整个控制过程进行了仿真试验，试验结果证明采用该模糊控制技术在控制温室的湿度和湿度时，系统响应快、超调量小、动作准确，过程平稳。  相似文献   

湿度、NaCl浓度对铜仁珍珠豆型花生种子活力及发芽的影响     

王琨 《现代农业科技》2020,(21)

研究发芽床不同含水量及NaCl浓度对铜仁珍珠豆型花生种子活力及发芽的影响,试验表明,发芽床含水量从20%升高至40%,铜仁珍珠豆型花生种子的发芽率、发芽势、发芽指数呈上升趋势,含水量继续升高至60%,三项指标呈下降趋势,40%是铜仁珍珠豆型花生最适发芽床含水量,花生发芽各项指标达到最高。用NaCl溶液处理种子,浓度从0mol/L升高至0.5mol/L,花生种子的发芽率、发芽势、发芽指数三项指标表现出先急剧后缓慢又急剧下降的趋势。  相似文献   

保鲜运输厢中不同湿度水平对制冷速率的影响     

王广海  陆华忠  吕恩利  李源泉  曾志雄 《安徽农业科学》2012,40(14):8376-8378

[目的]研究果蔬保鲜运输中加湿对制冷速率的影响。[方法]搭建了保鲜运输用温湿度控制试验平台,通过维持制冷过程中厢体内不同湿度水平,研究不同湿度水平对制冷速率的影响。[结果]制冷过程中,厢体内维持湿度水平越高,制冷时间越短,制冷机组降温速率越快。[结论]试验结果为果蔬保鲜运输过程中温湿度的综合控制提供了参考数据。  相似文献   

保鲜功能微生物对不同鲜切水果保鲜效果的研究   总被引：2，自引：0，他引：2  

车建美  郑雪芳  林抗美  刘波 《福建农业学报》2011,26(2):260-264

从西瓜根际土壤中分离得到保鲜功能微生物,经中科院微生物研究所鉴定为短短芽孢杆菌(Brevibacillus brevis),生产出微生物保鲜剂"果立鲜",孢子含量为10×108CFU·mL-1,稀释50倍后将其喷施于不同水果上进行保鲜效果观察.结果表明,在高温高湿条件下,"果立鲜"对龙眼、台湾大青枣、西瓜、苹果、皇冠梨...  相似文献   

校园绿化小气候效应及其对人体舒适度的影响——以山西农业大学校园为例   总被引：1，自引：0，他引：1  

王亚英  郝兴宇  蔺银鼎  袁浩  刘亚斌  王亢  王少恒  闫泳锦  张晓敏 《山西农业大学学报(自然科学版)》2011,31(2):117-120

为了明确校园绿化环境对校园小气候的影响,对校内3个绿化地和1个非绿化地进行了空气温度和湿度的对比观测,并利用校外自动气象站的温湿度资料和校内各测点温湿度进行了比较。研究表明:绿化可以使校内气温下降,空气湿度增加,从而增加人体的舒适感。校内绿地和非绿地空气温湿度与校外气象站的温湿度观测值极显著相关,并可以建立回归关系显著和决定系数(R2)较高的线性回归方程。校园绿化可以改善校内小气候环境,校内的小气候环境与校外大的气候环境密切相关。  相似文献   

烤烟套种甘薯对烟叶质量、烟薯产量及土壤温湿度的影响     

祖韦军  潘文杰  林叶春 《农学学报》2020,10(4):42-47

为筛选出适宜与烤烟套种的甘薯品种,解决部分烟区烤烟种植调茬难度大与综合效益低等问题,通过田间大区试验,研究烤烟套种不同甘薯品种对烟叶质量、烟薯产量及土壤温湿度的影响。结果表明,烟薯套种能够明显提升土壤相对含水率和烟叶产量,其相对含水率提高幅度介于12.03%~91.88%,烤烟产量增幅为12.29%~31.26%。烤烟套种甘薯以紫薯产量最高,块根产量达29400 kg/hm ²,且单薯质量大于100 g占总薯重的比例在紫薯中最高。烤烟套种甘薯提升了烤烟中上部烟叶的总糖和还原糖含量,降低了烟碱和总氮含量,有利于改善烟叶内在品质。烤烟套种甘薯降低了上部烟叶含梗率,但增大了上部烟叶叶面密度,以烤烟套种紫薯表现突出。烤烟与紫薯套种,可作为一种烟田增产、烟叶增值和烟农增收的种植模式。  相似文献   

基于AT89C2051的温室大棚气象要素预警控制系统     

周世新  尤军  李艺文  陈洪利 《安徽农业科学》2015,(33)

控制蔬菜大棚内的温度和湿度是提高蔬菜大棚的产量和防止病虫害发生的重要措施,而监测风速是为了防止大风损毁蔬菜大棚.该研究中的蔬菜大棚气象要素监测预警系统是以AT89 C2051单片微型计算机为核心,针对蔬菜大棚内温度湿度和大棚外风速监测而设计,它能有效控制蔬菜大棚内的温度和湿度,提高蔬菜大棚的产量,减少大风灾害造成的损害.  相似文献