毛皮质量的营养调控     

赵国先  宋智娟  张晓云  李岁寒  张妍 《中国饲料》2005,(13):5-6

影响毛皮质量的因素很多,如品种、性别、年龄、生理状况、饲料营养、饲养管理、加工过程等。本文从饲料营养水平、添加剂的使用等角度论述营养与毛皮品质的关系。  相似文献   

半导体消雷器在县级电力系统中的应用     

洪希度  陈满园 《中国农村水利水电》1993,(5)

取代传统避雷针的一种新型防雷装置——半导体消雷器已经问世。本文根据半导体消雷器的性能特征,以电力系统为应用领域,提出了将半导体消雷器组成联合保护网带的方法,总结了运用半导体消雷器的实际经验。  相似文献   

Spatial association between northern fur seal (Callorhinus ursinus) and potential prey distribution during the wintering period in the northern Sea of Japan          下载免费PDF全文

Takanori Horimoto  Yoko Mitani  Yasunori Sakurai 《Fisheries Oceanography》2016,25(1):44-53

Elucidating the response of marine predators to oceanographic features helps in understanding their foraging strategies and the cause of their spatial overlap and interference with fishery activities. Northern fur seal is a highly pelagic species during the wintering period. In recent years, fur seals have consistently been found distributed near the coast of southwest Hokkaido, Japan. Because interference by fur seals with coastal fishery activities has become a serious concern, an understanding is sought as to why fur seals come ashore in this area. We conducted ship‐based observations and estimated fur seal density. To elucidate the spatial and seasonal association of fur seal distribution and ocean environments, we constructed statistical models to describe how potential prey distribution and oceanographic features influenced the fur seal spatial distribution during the wintering period. Fur seal distribution corresponded markedly to potential prey distribution, and they tended to aggregate along the narrow continental shelf that is the main geographic feature of this area, which is 2000 m deep and approximately 10 km from the coast. Walleye pollock [Gadus chαlcogrαmmα (Theragra chαlcogrαmmα)] and arabesque greenling (Pleurogrammus azonus), which are one of the main prey for fur seals, move to the shallow area to spawn on the continental shelf seasonally, so potential prey abundance could be higher in coastal areas than offshore. Moreover, the absence of a mesopelagic biotic community may be one of the main factors in the coastal distribution of the fur seal.  相似文献   

防盗报警、电视监控系统的布线及供电系统设计     

徐宏 《林业科技情报》2003,35(2):60-60

本文从防盗报警、电视监控系统的布线及供电系设计二方面,论述了在进行防盗报警电视监控系统设计时,必须严格按有关设计规范布线,尽量做到经济合理、安全可靠。  相似文献   

中国6种犬科动物直针毛的扫描电镜分析   总被引：3，自引：0，他引：3  

侯森林 《安徽农业大学学报》2010,37(4)

应用扫描电镜对我国分布的6种犬科动物背部和腹部直针毛的鳞片花纹类型进行研究.结果表明,6种犬科动物直针毛鳞片花纹类型主要有杂波型、长瓣型、杂瓣型、扁平型和方瓣型,毛鳞片形态在属间和种间存在差异,同一种类身体不同部位毛的鳞片形态也有差异,同一根毛的不同部位也存在差异.依据本项研究,笔者探讨了利用犬科动物毛鳞片花纹进行物种识别的可行性及需要注意的问题.  相似文献   

用西瓜叶片气孔保卫细胞叶绿体数鉴定西瓜染色体倍性   总被引：6，自引：0，他引：6  

施先锋  彭金光  汪李平 《湖南农业大学学报(自然科学版)》2009,35(6)

为了寻求简便、快速的西瓜染色体倍性鉴定方法,以二倍体西瓜TS和0517及其同源四倍体为试材,通过观察叶片气孔保卫细胞叶绿体数来鉴定西瓜染色体倍性.结果表明,两倍性间的叶绿体数差异显著.二倍体叶绿体数在15个以下,四倍体叶绿体数大于等于15个;气孔叶绿体数随染色体倍性的增加而增加,用气孔保卫细胞叶绿体数预测植株倍性的准确率可达90.2%,因此,用万能荧光显微镜观察叶绿体数可以在苗期快速、准确地确定植株的染色体倍性.  相似文献   

The influence of the hemoglobin concentration in growing mink kits on certain skin characteristics     

Anne Nveri  Jouni Kangas  Jaakko Mkel 《Acta veterinaria Scandinavica》1984,25(1):50-56

The relationship between some skin characteristics and hemoglobin values during the growth period were statistically examined in standard male minks. Significant correlations) (P < 0.05–0.001) were found between the hemoglobin concentrations determined at 3 points during the growth period (in July, August and November) and the density and colour of underfur, and skin length, respectively. According to the study even the early hemoglobin values in July and August have a significant influence on the size and quality of the pelt. Mink kits with low hemoglobin values are liable to develop a winter fur coat with defective pigmentation and hair structure of the underfur. Anemic minks develop the most extreme stage of the pigmentation defect and these so-called cotton fur skins have little value in the fur garment industry. When these abnormal hemoglobin values are recognized at an early stage, cotton fur skins may be avoided, and larger skins of better quality may be produced.  相似文献   

城市化进程中失地农民问题的思考与对策     

张军涛  刘建国 《农机化研究》2008,(2):222-226

随着我国城市化进程的加快,越来越多的农村人口变成了城市人口,导致数以千万计的农民失去了自己的土地,一些地方农民的利益没有得到很好的保障,使处于新生存环境的农民面临着被"边缘化"的危险.失地农民问题是我国城市化进程中出现的新问题,是一个事关我国城市化能否实现可持续发展和整个社会改革发展稳定的大问题.为此,从我国征地补偿标准过低、征地程序不完善和政府角色错位在征地过程中存在失范行为等视角探悉我国城市化进程中农村征地存在的问题,以寻求解决之道.  相似文献   

浅谈自然保护区在湖北生态建设中的地位与作用     

李建军 《湖北林业科技》2003,(4):43-45

随着全国野生动植物保护和自然保护区建设工程的实施 ,自然保护区在我省生态环境建设中的地位与作用越来越重要 ,运用生物多样性管护区的理论指导我省的自然保护区建设将是正确认识自然保护区地位与作用的关键所在。  相似文献   

Avoiding edge effects in agroforestry experiments; the use of neighbour-balanced designs and guard areas     

S. Langton 《Agroforestry Systems》1990,12(2):173-185

A number of different types of edge effects on experimental plots are defined, and it is shown that they are frequently important in agroforestry experiments. Methods of eliminating edge effects, either at the design or the analysis stage, are described. Computer simulations, based on uniformity data, are used to investigate the efficacy of neighbour-balanced designs, with and without neighbour terms, for reducing the problem of neighbour effects between different treatments. It is concluded that, while neighbour-balanced designs may be useful in certain situations or in combination with other methods, it is preferable to eliminate edge effects by using adequate guard rows. Recommendations are therefore made concerning the correct use of guard areas in agroforestry experimentation.  相似文献