The Application of GIS in Small Watershed Classification in Loess Plateau     

Zhu Jinzhao  Wu Bin  Bi Huaxing  Zhou Changqing College of Soil  Water Conservation  Beijing Forestry UniversityBeijing  P.R.China 《中国林学(英文版)》1994,(2)

ＴｈｅＡｐｐｌｉｃａｔｉｏｎｏｆＧＩｓｉｎＳｍａｌｌＷａｔｅｒｓｈｅｄＣｌａｓｓｉｆｉｃａｔｉｏｎｉｎＬｏｅｓｓＰｌａｔｅａｕＺｈｕＪｉｎｚｈａｏ，ＷｕＢｉｎ，ＢｉＨｕａｘｉｎｇ，ＺｈｏｕＣｈａｎｇｑｉｎｇＣｏｌｌｅｇｅｏｆＳｏｉｌａｎｄＷａｔｅｒＣ...  相似文献   

星星草治理草原碱斑的效果与种植技术     

赵喜印  佟振宇 《草业科学》1992,9(5):61-62

  相似文献   

Biochemical Changes in Freshwater Prawn Macrobrachium rosenbergii During Larval Development     

Paymon  Roustaian Mohd Salleh  Kamarudin Hishamuddin Bin  Omar Che Roos  Saad Mansor Haji  Ahmad 《Journal of the World Aquaculture Society》2001,32(1):53-59

Abstract.— Quantitative changes in the protein, lipid and carbohydrate were studied in the early larval stages of developing freshwater prawn Macrobrachium rosenbergii reared under fed and starved conditions to understand the relative importance of these nutrients in energy metabolism of the growing larvae. Larvae obtained from several females were stocked into three 250-L tanks at a density of 30 larvae/L. The feeding regime consisted of newly hatched Artemia nauplii. Protein was always the major organic constituent followed by lipids and then carbohydrates of both fed and starved larvae. Protein levels of both fed and starved larvae increased during development, suggesting an important role in morphogenesis. The decline of lipid during the larval growth that was more rapid for starved larvae, suggests a probable utilization of lipid as the major metabolic source of energy. Carbohydrates formed less than 5 and 2.4% of the larval dry weight of fed and starved larvae, respectively, suggesting their limited role in larval metabolism.  相似文献   

室内型胶合板天然耐久性的初步研究     

吕斌  付跃进  吴盛富  杨帆 《林产工业》2004,31(4):17-20

作为一项反映材料优劣的重要的评价指标,天然耐久性直接决定了材料的使用寿命.笔者通过对胶合板胶合强度性能连续14年的跟踪测定,讨论和分析了胶合板的天然耐久性.最后总结出了胶合板在使用过程中随时间迁移其胶合强度性能随外界变化的规律,以期为胶合板的生产制备、生产工艺的改进及其应用领域的拓宽等方面起到一定的指导作用.  相似文献   

阔叶次生林抚育改造初探     

蔡学林  张志云  罗天裕  邓冰涓 《江西农业大学学报》1992,(6)

安远县国营林场根据生态学原理,对阔叶次生林进行改造,把天然更新和人工改造更新有机的结合起来。通过改造可很快的形成多树种的混交林,林木材积生长提高115％～219％,土壤物理性比杉木纯林好,土壤贮水量比杉木纯林提高57％～92％,有良好的生态经济效益。实践证明,次生林改造是次生林经营的重要措施,是加速培育森林资源的好途径。  相似文献   

大岛樱病虫害及其防治的研究     

张民兴  张忠民 《经济林研究》1996,14(2):14-16

本文对大岛樱中国引种点危害较严重的４种病害和２种害虫进行观测和种类鉴定，指出了各病虫害的危害症状和发生发展规律等，并试验或介绍了相应的防治措施。  相似文献   

苏云金杆菌与杀灭菊酯防治红铃虫的试验          下载免费PDF全文

罗绍彬  蔡昌建  阎建平  梁世平  张用梅  张益  杨喜凤 《植物保护学报》1985,12(3):213-216

苏云金杆菌(Bailus thuringiensis)140或018工业菌剂每亩用200～255克,加杀灭菊酯20%乳剂每亩8毫升混用防治第二、三代红铃虫,虫口减退率和铃害下降率分别为80.5～93.4%和68.8～84.6%;杀灭菊酯每亩40毫升单用效果分别为96～97.2%和84.6～95.8%,都能有效控制红铃虫的危害。棉花产量测定表明,菌剂加菊酯混用使皮棉增加21.3～30.9%,菊酯单用增加11.4%。  相似文献   

固支矩形底扁球壳的边界几何缺陷     

蔡松柏  王选民 《湖南农业大学学报(自然科学版)》1991,18(3)

In this paper, concept of boundary geometrical imperfection during postbuckling process for shallow spherical shell is first presented. The effects of the declination of the rectangular boundary on postbuckling process are also studied by integrated metho  相似文献   

多花黑麦草播期试验(1987～1988年)     

易克贤  詹爱民  刘斌  王贵兰  周省善  陈哲忠  肖小文  傅新如 《江西农业大学学报》1991,(6)

本试验研究了7个不同播期对多花黑麦草出苗、生产性能的影响.结果表明:在江西清江种草养畜试验站从8月中旬至11月中旬均可播种多花黑麦草,尤以9月中旬至10月中旬更为适宜.  相似文献   

木瓜剖分原理研究及新机型设计     

王晓光  彭斌  陈宏  陈明森 《农机化研究》2009,31(1)

针对我国目前对木瓜剖半设备研究较少,剖切方式不合理,切割效果差等问题,设计开发了新型木瓜剖半机。该机切割方式选用滑切切割的方式,由运料系统、切割系统、出料系统组成,设计合理,结构简单。为此,计算了滑切角、切割角等主要切割参数,并给出了新型剖半机的主要技术参数。试验表明:该机切割效果好,能够有效提高生产效率。  相似文献