Scomber japonicus, H. is a better candidate species for juvenile production activities than Scomber scombrus, L.     

Diego Mendiola  Yoh Yamashita  Michiya Matsuyama  Paula Alvarez  & Masaru Tanaka 《Aquaculture Research》2008,39(10):1122-1127

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内蒙古阿拉善左旗4年采用机械模拟飞播牧草效益调查     

吴雨俊  郎海峰 《草业科学》1998,15(6):47-50

阿拉善左旗４年机械模拟飞播牧草累计面积为２９８０ｈｍ＾２，实播面积为２９８０ｈｍ＾２，１９９７年１０月调查，保存面积为２９７０ｈｍ＾２，保存面积率为９９．７％，４年来播区植被盖度提高８．９６倍，有苗面积率提高３１．５３倍，牧草产量提高３５．９１倍，第一性生产产值和第二性生产产值分别是飞播总投资的０．６７倍和０．９７倍，机械模拟飞播牧草表现出明显的经济效益、生产效益和社会效益。  相似文献   

柴达木盆地次生盐渍化撂荒地的改良与利用   总被引：7，自引：0，他引：7  

马玉寿  李青云 《草业科学》1997,14(3):17-20

在分析了柴达木盆地次生盐渍化撂荒地的成因的基础上，对生物改良和利用撂荒地的大量试验结果进行了分析和总结，提出了封育一灌溉和建植入工草是改良与利用盐渍化撂荒化撂荒地的有效途径，并阐述了在柴达木盆地建立草地农业生态系统的必要性 。  相似文献   

Der Humus als Ganzes     

Richard Lang 《Forstwissenschaftliches Centralblatt》1932,54(12):389-405

Ohne Zusammenfassung  相似文献   

Studien zur forstlichen Düngung     

Richard Lang 《European Journal of Forest Research》1933,55(18):638-651

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森林减少水灾效益评价(英文)     

郎璞玫  李海奎  宋彩平  陈炎  袁志强 《林业研究》2001,12(1):71-72

本文以森林内涵机理分析为基础，定义了森林减轻水灾的效益。通过对森林减轻水灾效益的 性质分析，指出对该效益的研究不能采用微观分析法，只能采用宏观分析法。利用1998年长 江发生特大洪水的案例，首次在较大的范围内，对森林减轻水灾的效益作出了科学地评价。 尽管恢复森林植被是控制洪水的基本途径，但森林减轻水灾的效益只相当于所有水利部门应 当承担总效益的5%。  相似文献   

Experimente mit Erregern der Umfallkrankheit     

K. J. Von Lang 《Forest Pathology》1976,6(1):46-56

Experiments with fungi causing damping off. II. Infections of conifer seedlings of different provenances with one or more damping-off fungi and Triclioderma viride Pers. ex Fr. Provenances of native conifer seedlings show varying susceptibility to the agents of damping-off. Following infections with damping-off fungi together with Tricboderma viride increased disease symptoms often appeared. Thus the antagonist seemingly increases the susceptibility of the treated seedlings.  相似文献   

美国五种灌木种实形态特征及其萌发特性的初步研究     

蓝登明  李春红  杨学文 《内蒙古林业科技》2006,32(3):39-42

采用常规的水浸催芽方法,对引自美国的5种共7个种源的灌木树种种实的萌发特性进行了初步研究。对水浸催芽不易萌发的种实再采取其它催芽方法进行实验。结果表明:黑油脂木(Sarcoba tusverm icula tus)和沙生胶兔木(Chrysotham nus nauseosus ssp.turbina tus)的果实特别容易萌发,采用常规水浸处理即可得到较高的发芽率;不作任何处理即进行直播,其出苗率也很高;而四翅滨藜(Atriplex canescens)、巨四翅滨藜(A.canescens ssp.gigan tea)、三齿滨藜(Atriplex.triden ta ta)和内华达麻黄(Ephedranevadensis)的种实,常规水浸处理发芽率很低,通过混沙催芽、层积催芽等方法可以提高种实的发芽率和出苗率。  相似文献   

永康工业区绿化现状及发展对策   总被引：1，自引：0，他引：1  

李浪 《浙江林业科技》2005,25(3):75-78

分析了永康市工业园区绿化现状及存在问题,提出了实行绿化"三同时"制度(同时规划设计、同时施工、同时验收),选用乡土树种、彩叶树种绿化,建成生态工业区、观光工业区的工业区绿化发展对策.  相似文献   

Field attraction of Cerambyx welensii to fermentation odors and host monoterpenes     

Israel Sánchez-Osorio  Gloria López-Pantoja  Antonia M. Paramio  José L. Lencina  Diego Gallego  Luis Domínguez 《Journal of pest science》2016,89(1):59-68

Cerambyx welensii Küster is one of the greatest threats to Quercus suber L. and Quercus ilex L. in Spain. Efficient control methods for this species are currently being tested, and the use of traps baited with food-related products for their monitoring and control has been proposed. Cerambyx welensii adults prefer to colonize old or decayed trees, in which cortical exudates frequently release fermentation odors. Fermentation-related compounds, such as ethanol, have been cited as attractants to various hardwood woodborers (as Cerambyx cerdo L.), used either alone or sometimes in combination with other host odors. In this work, we conducted field experiments to ascertain whether chemical blends mimicking fermentation odors were attractive for C. welensii. To this end, we used three types of traps (multiple funnel, cross-vane and single-funnel) baited with six synthetic blends including one or more fermentation-related chemicals (ethanol, ethyl acetate, 3-methyl-1-butanol, acetaldehyde, 2-methyl-1-propanol and 2-methyl-1-butanol), various food-related products (beer, melon and red wine mixed with peach juice) and host monoterpenes (α-pinene, β-pinene, limonene, α-phellandrene and camphene). At high release rates (5–11 g/day), various synthetic blends proved attractive irrespective of trap type. Our results contribute to understand the impact of volatile organic compounds in host selection by woodborers infesting deciduous trees. The results hold promise for optimizing trapping strategies to control C. welensii within an integrated pest management framework.  相似文献