退化人工草地补播更新试验初报

3年试验表明,施肥是恢复人工植被,保持人工牧草稳定、高产的关键性措施,并对速生性杂草有明显抑制作用。不同草种需选择不同补播期和补播方式进行补播,做到耙地与施肥,封育和除杂相结合。     

野生墨汁鬼伞的驯化与栽培

以北京市怀柔区宝山镇野生墨汁鬼伞(Coprinus atramentarius)为试验材料,对其母种、原种培养基配方进行优化筛选,并采用不同栽培方式研究了野生墨汁鬼伞人工驯化的培养条件。结果表明:实验范围内供试菌株的菌丝体生长最适碳源为葡萄糖+玉米淀粉,最适氮源是蛋白胨,最适pH值为9。培养料配方以棉籽壳、麸皮、玉米粉、石灰、锯末、石膏的配方最好,出菇以菌棒立栽覆土效果最好,覆土后55d现菇蕾,3～5d可采收。第一潮出菇生物学效率可达40%左右,条件适宜可出3～4潮菇。     

Growth and photosynthetic responses of Canarium pimela and Nephelium topengii seedlings to a light gradient

We analyzed the growth and photosynthetic responses of Canarium pimela K. D. Koenig (Chinese black olive) and Nephelium topengii (Merr.) H. S. Lo. (Hainan shaozi) to a light gradient to recommend better procedures for optimizing seedling establishment and growth of both species in restoration and agroforestry practices. One-month-old seedlings were exposed to four irradiance levels (46, 13, 2 and 0.2 % full sunlight) inside shade cloth covered shadehouses for 1 year. With decreased sunlight both species displayed trends of decreased relative growth rate (RGR) and leaf area (LA), and increased specific leaf area and leaf area ratio (LAR). The mean values of light-saturated net photosynthetic rate (Pmax) in 46 and 0.2 % full sunlight were 10.11 and 3.44 μmol CO₂ m^?2 s^?1 for C. pimela and 6.26 and 3.47 μmol CO₂ m^?2 s^?1 for N. topengii, respectively. C. pimela had higher RGR in 46 and 13 % full sunlight than in 2 and 0.2 % full sunlight. Differences in growth rates can be explained by the different values of LA, LAR and leaf mass ratio, as well as by the different values of photosynthetic saturation irradiance and net photosynthetic rate (Pmax) between the two species. Both morphological and physiological responses to shading indicate N. topengii could be rated as “very shade-tolerant,” while C. pimela could be rated as “intermediately shade-tolerant”.     

建立专业集团开发优势资源发展平原农区林业产业

在社会主义市场经济条件下,要保证平原农区林业持续发展,不仅要确立农业主导地位,正确处理好农林发展关系,而且要遵守市场规律,从低效益的林业种植业向高效益的林业产业发展,使农民从林业产业生产中直接获得较好的经济效益,把发展林业的积极性建立在自觉自愿的基础上。兰考县建立兰桐林业集团,开发利用泡桐优势资源,以公司加农户的组织形式,进行贸工林一体化建设,发展林业产业,取得显著效益,为平原农区林业产业的建设与发展走出了一条新路。     

塔落岩黄芪、细枝岩黄芪及其变异型的生理特性研究

本文研究了毛乌素沙漠地区塔落岩黄芪和细枝岩黄芪及其变异型的生理学特性。结果表明,塔落岩黄芪和细枝岩黄芪各与其变异型之间在生理特性方面存在着极其显著的差异。     

有限元法在材料力学中的应用

有限元法在工程技术的领域得到了广泛的应用,它是一种利用固体理论基础的数值分析方法,本文主要探讨有限元法在材料力学中的应用。     

天祝县牧区开发示范工程项目草地围栏建设及其综合效益

天祝县牧区开地示范工程项目１９９５年由农业部和国家计委审批立项,１９９６年全面启动建设,该项目以良种繁育,疫病防治,草地建设,技术服务四大体系为主体建设内容,并于１９９８年８月通过验收,围栏是草地建设体系的主要建设内容,在突出生产性,公益性,基础性建设原则的基础上,自１９９６年以来累计建成４０００ｈｍ＾２建成后,经综合改良,使草地植被得以迅速恢复,平均增产鲜草１６５３ｋｇ／ｈｍ＾２,年创经济效益３     

The Analysis of Trend of Development of Technology of Reusing Solid Waste in Our Country

To analyse the situation of industrial solid waste in our country,tracking thetrend of development of technolog of reusing solid waste in outer country,connecting with researchof statement ,we can point out standing on comprehensive utilization ,breaking through key technolco-gy, improving utilization factor, keeping at popelaration,it is in vitably trend to advamce the devel-opment of technology of reusing solid waste in our country.     

基于IMU的细粒度奶牛行为判别

针对奶牛行为判别自动化水平不足、准确率低的问题,采用惯性测量单元(IMU)和卷积神经网络(CNN),对细粒度奶牛行为判别进行研究.结果表明:1)在KNN、SVM、BPNN、CNN和LSTM 5个模型中,CNN模型在奶牛行为分类测试集上的准确率最高.2)含有三轴加速度计、陀螺仪和磁力计的IMU更加适用于奶牛行为分类,其分...