Trophic structure and energy fluxes in a grass carp (Ctenopharyngodon idellus) cultured pond ecosystem     

Bo Zhou  Shuanglin Dong  Fang Wang 《Aquaculture International》2015,23(5):1313-1324

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基于FTA的船舶冷藏集装箱故障的建立     

王富银  郑学林 《绿色科技》2011,(1):162-164

介绍了故障树分析法,并进行了理论分析,探讨了通过采用故障树分析方法,建立起船舶冷藏集装箱的故障集.  相似文献   

农业工程领域中英语学习模式的研究     

王艳  衣淑娟 《农机化研究》2011,33(7)

农业工程关乎人类生存的基础,为世界各国所重视.英语是世界上应用最广泛的语言之一,尤其在科技文献中占有主导地位.为此,以农业工程领域为出发点,结合高校英语学习的现状,探讨了农业工程领域英语学习的主要模式,旨在为我国现代化大农业的发展提供有益的借鉴.  相似文献   

柞蚕幼虫黄体色与白体色的遗传分析及类胡萝卜素组成比较     

苏鑫  郭剑  刘珅凯  李群  李响  王奇  李木旺  潘茂华  刘彦群 《蚕业科学》2021,47(5):430-434

为深入探讨柞蚕幼虫体色多样性的形成机制,分析柞蚕品种豫大1号(黄体色)和白一化(白体色,略带黄色)幼虫体色的遗传规律,并比较二者在体壁类胡萝卜素组成上的差异.杂交试验发现,F1的幼虫体色为黄色,F2有黄色和白色两种表型,且分离比符合3∶1;回交BC1(F1×豫大1号)均为黄色,而BC1(F1×白一化)则有两种表型,即黄色和白色,分离比符合1∶1.遗传分析表明,豫大1号的基因型为YYGG,白一化的基因型为YYgg,豫大1号的黄体色对白一化的白体色属于完全显性遗传.代谢组学分析发现,豫大1号中的类胡萝卜素含量(10.259μg/g)远高于白一化(1.167μg/g);白一化体壁中的叶黄素、β-胡萝卜素和玉米黄质含量远小于豫大1号.综上认为,体壁中类胡萝卜素的缺乏是导致白一化形成白体色的原因之一.  相似文献   

艾纳香内生真菌抗细菌和炭疽菌的活性研究     

元超  舒雪纯  张影波  王凯  谢小丽  徐子琪  袁媛 《中国农学通报》2021,37(23):38-44

为获得丰富的艾纳香内生真菌资源,筛选出抗性生防菌株,用于活性次生代谢产物的发现,通过水琼脂法对海南产艾纳香进行内生真菌分离,通过ITS序列分析,对其进行鉴定和分析。采用滤纸片法评价内生真菌发酵产物对细菌的抑制活性,采用平板对峙培养法评价艾纳香内生真菌对植物炭疽菌的拮抗作用。本研究共分离鉴定出191株内生真菌,分属于27属,45种,其中优势菌属为Diaporthe、Paraphoma、Ectophoma、Penicillium、Talaromyces、Hypoxylon、Phomopsis、Colletotrichum和Fusarium。抗细菌活性结果显示,Clonostachys、Fusarium和Diapothe属活性较强。抗炭疽病菌试验显示,Talaromyces、Ectophoma和Penicillium属活性较强。本研究初步探讨了海南产艾纳香内生真菌种类的多样性,并首次对其进行了抗病原菌活性筛查,获得的活性菌株可作为微生物源菌剂开发的重要材料。  相似文献   

棉花单核苷酸多态性标记研究进展   总被引：1，自引：0，他引：1  

王振玉  李威  周晓箭  裴小雨  刘艳改  周克海  张文生  孟清芹  王海风 《棉花学报》2016,28(4):399-406

单核苷酸多态性标记已在农作物研究中得到广泛应用并取得重大进展。为了便利棉花SNP(Single nucleotide polymorphism)标记的研究和应用,介绍了利用基因芯片、简化基因组测序、重测序等在棉花中开发SNP标记的方法 ,综述了SNP标记在棉花遗传图谱构建、数量位点的定位和分子标记辅助育种、基因组测序以及系统进化等研究中的应用。并对异源四倍体棉花中SNP标记开发时,同源序列位点和部分同源序列位点上的SNP标记辨别问题进行了系统探讨,对其快捷的开发、检测方式和在数量基因定位中的应用前景进行了展望。  相似文献   

Characterizing long-term forest disturbance history and its drivers in the Ning-Zhen Mountains,Jiangsu Province of eastern China using yearly Landsat observations (1987–2011)     

Mingshi Li  Chengquan Huang  Wenjuan Shen  Xinyu Ren  Yingying Lv  Jingrui Wang  Zhiliang Zhu 《林业研究》2016,27(6):1329-1341

Forest losses or gains have long been recognized as critical processes modulating the carbon flux between the biosphere and the atmosphere. Timely, accurate and spatially explicit information on forest disturbance and recovery history is required for assessing the effectiveness of existing forest management. The major objectives of our research focused on testing the mapping efficacy of the vegetation change tracker (VCT) model over a forested area in China. We used a new version of VCT algorithm built upon the Landsat time series stacks (LTSS). The LTSS consisted of yearly image acquisitions to map forest disturbance history from 1987 to 2011 over the Ning-Zhen Mountains, Jiangsu Province of east China. The LTSS consisted of TM and ETM+ scenes with different projections due to distinct data sources (Beijing remote sensing ground station and the USGS EROS Center). The validation results of the disturbance year maps showed that most spatial agreement measures ranged from 70 to 86 %, comparable with the VCT accuracies reported for many places in USA. Very low accuracies were identified in 1995 (38.3 %) and 1992 (56.2 %) in the current analysis. These resulted from the insensitivity of the VCT algorithm to detect low intensity disturbances and also from the mis-registration errors of the image pairs. Major forest disturbance types existing in our study area were identified as agricultural expansion (39.8 %), urbanization (24.9 %), forest management practice (19.3 %), and mining (12.8 %). In general, there was a gradual decreasing trend in forest cover throughout this region, caused principally by China’s economic, demographic, environmental and political policies and decisions, as well as some weather events. While VCT has largely been used to assess long term changes and trends in the USA, it has great potential for assessing landscape level change elsewhere throughout the world.  相似文献   

人居环境视角下居民垃圾分类意愿实证研究及政策建议——基于河南省郑州、洛阳、商丘和漯河四地市的调研     

李凤琴  韩灵梅  李静  王菲  王贞 《绿色科技》2021,(4)

基于河南省人居环境现状,分别对郑州、洛阳、商丘和漯河四地市进行了实地调研,通过建立二元Logistic模型,分析了影响居民垃圾分类意愿高低的因素。结果表明:文化程度、经济发展、政策支持对提高居民垃圾分类意愿具有较强的正相关影响,而居民人居环境满意度对提高垃圾分类意愿具有负相关影响;女性相比男性的垃圾分类意愿更高,城市居民相比农村居民的垃圾分类意愿更高。基于此结论,从政府和社会两个方面分别提出了相关建议,以供参考。  相似文献   

Soil organic and inorganic carbon sequestration by consecutive biochar application: Results from a decade field experiment     

Siwei Shi  Qingzhong Zhang  Yilai Lou  Zhangliu Du  Qian Wang  Ning Hu  Yidong Wang  Anna Gunina  Jiqing Song 《Soil Use and Management》2021,37(1):95-103

Biochar addition can expand soil organic carbon (SOC) stock and has potential ability in mitigating climate change. Also, some incubation experiments have shown that biochar can increase soil inorganic carbon (SIC) contents. However, there is no direct evidence for this from the field experiment. In order to make up the sparseness of available data resulting from the long‐term effect of biochar amendment on soil carbon fractions, here we detected the contents and stocks of the bulk SIC and SOC fractions based on a 10‐year field experiment of consecutive biochar application in Shandong Province, China. There are three biochar treatments as no‐biochar (control), and biochar application at 4.5 Mg ha^?1 year^?1 (B4.5) and 9.0 Mg ha^?1 year^?1 (B9.0), respectively. The results showed that biochar application significantly enhanced SIC content (3.2%–24.3%), >53 μm particulate organic carbon content (POC, 38.2%–166.2%) and total soil organic carbon content (15.8%–82.2%), compared with the no‐biochar control. However, <53 μm silt–clay‐associated organic carbon (SCOC) content was significantly decreased (14%–27%) under the B9.0 treatment. Our study provides the direct field evidence that SIC contributed to carbon sequestration after the biochar application, and indicates that the applied biochar was allocated mainly in POC fraction. Further, the decreased SCOC and increased microbial biomass carbon contents observed in field suggest that the biochar application might exert a positive priming effect on native soil organic carbon.  相似文献   

农业现代化过程中我国农机合作社的特点、困境与对策     

王勇 《农机化研究》2010,32(9)

我国正处在从传统农业向现代农业转变的关键阶段.高度的农业机械化是现代农业的一个重要特征.我国农机作业合作社发展迅速,积累了大量的成功经验,但是也面临着一些问题,需要从加强对农机作业合作社人员的教育与培训、增加农机作业合作社的规模化效益、完善农机作业合作社内部运行机制和政府营造良好的外部环境等方面予以解决.  相似文献