Study on ambient noise in sawmill’s workshop

Ambient noise in 13 sawmill’s workshops was tested and analyzed to reveal its character and regularity. The situation of the ambient noise in sawmill’s workshops was evaluated     

Achieving food and nutritional security through agroforestry: a case of <Emphasis Type="Italic">Faidherbia albida</Emphasis> in sub-Saharan Africa

Faidherbia albida is an ideal agroforestry tree commonly intercropped with annual crops like millet and groundnuts in the dry and densely populated areas of Africa. With its peculiar reverse phenology, it makes growth demands at a different time from that of crops. In addition, it deposits great amount of organic fertilizer on food crops. Leaves entering soils are comparable to fertilization of almost 50 t·ha 1 ·year 1 of manure in dense stands of 50 large trees per ha. These nutrients help maximize agricultural production and reduce the need for a fallow period on poorer soils. Research has shown that millet grown under F. albida yielded 2.5 and 3.4 fold increases in grain and protein, respectively. Animals eat pods which contain mean amounts of crude protein of 20.63% and carbohydrate of 40.1% in seeds. Moreover, the continued existence of F. albida in agroforestry parklands as in Ethiopia and Mali signifies the success of traditional conservation measures. Modern scientists have also developed much interest in the role of agroforestry in maintaining long-term biological balance between agriculture and livestock production systems. To ensure food security, which still remains a major challenge in sub-Saharan Africa, and concurrently minimize environmental degradation, promotion of agroforestry that specifically involves indigenous trees is crucial. We discuss the prospective role of F. albida in alleviating poverty while simultaneously protecting the environment from factors associated with, for example, deforestation and loss of biodiversity. The overall aim is to promote wide-scale adoption of F. albida as a valuable tree crop in farming systems, particularly in those areas where it remains unexploited.     

Two new chalcone glycosides from the stems of Entada phaseoloides

Two new chalcone glycosides 4′-O-(6″-O-galloyl-β-d-glucopyranosyl)-2′,4-dihydroxychalcone (1) and 4′-O-(6″-O-galloyl-β-d-glucopyranosyl)-2′-hydroxy-4-methoxychalcone (2) together with one known chalcone glycoside 4′-O-β-d-glucopyranosyl-2′-hydroxy-4-methoxychalcone (3) were isolated from the stems of Entada phaseoloides. The structures of the new compounds were elucidated on the basis of extensive spectroscopic analysis, including HSQC, HMBC, ¹H–¹H COSY, and chemical evidences. This is the first report of chalcone-type compounds isolated from the genus Entada.     

对人工林非森林问题的探讨

人工林早已被人们所熟悉。在我国,有人工栽植树木,可追溯到1600年前;有成型的人工林时代,也有600年历史了。然而,世人热衷于人工林,主要还在于工业时代的到来,特别是近200年来。现在的人工林问题,已是全球关注的热点问题,这大致有两个原因:一个是环境问题,一个是利益问题。可是,至今为止,人工林非森林问题,并没有得到我们大家的接受,亦或我们的公众并不知道,人工林并不是森林。基于人工林问题的至关重要性,笔者认为,有必要通过讨论,达成共识,以便于对人工林的种种问题,有一个理性的、较早的觉醒。     

Two new polyols and a new phenylpropanoid glycoside from the basidiomycete Lactarius deliciosus

Two new polyols, 3-hydroxymethyl-2-methylenepentane-1,4-diol (1) and 1-methylcyclohexane-1,2,4-triol (2), and a new phenylpropanoid glycoside, eugenyl 4″-O-acetyl-β-rutinoside (3), together with seven known steroids (5–11) were isolated from the fruiting bodies of the basidiomycete Lactarius deliciosus. The structures of these compounds were elucidated by the analysis of spectroscopic data.     

湿加松一年生母树萌条扦插效果分析

选用1年生湿加松母树萌条,分别设基部萌条与顶部促萌条、抽梢与未抽梢的顶部促萌条、顶端次生叶及穗条长度不同的顶部促萌条进行扦插试验。结果表明:(1)基部萌条与顶部促萌条、抽梢与未抽梢的顶部促萌条在扦插生根率、扦插苗根系生长、抽梢生长的差异均不显著;四类穗条扦插均可获得较高生根率,根系和抽梢生长快。(2)不同顶端次生叶长度的顶部促萌条在生根率、不定根数量上均存在极显著差异,而根系级数、须根数量及抽梢长度方面差异不显著;顶端次生叶长度0~3 cm的顶部促萌条扦插效果好。(3)不同长度的顶部促萌条制成的穗条其扦插苗抽梢长度存在极显著差异,生根率存在显著差异,根系生长差异不显著;最好选长于10 cm的顶部促萌条制成长8~10 cm的插穗扦插效果好。结合生产上扦插用育苗袋的大小及扦插深度,对1年生湿加松母株,选用顶端次生叶长3 cm以下,长8~10 cm的顶部促萌条或基部萌条扦插效果较好,要用顶端次生叶长大于3 cm的顶部促萌条扦插,只能剪取萌条长10 cm以上且制成短于10 cm的穗条扦插才能达到较好的效果。     

喀斯特山地主要适生树种幼苗耗水量季节变化及对土壤干旱的响应

本文通过对柳杉等24个喀斯特山地主要适生树种一年生幼苗不同季节的耗水量进行比较研究、各树种幼苗在不同土壤干旱水平(A:无干旱胁迫;B:轻度胁迫;C:中度胁迫;D:重度胁迫)下的耗水量比较研究,结果表明:各树种幼苗耗水量的季节变化为:常绿树种幼苗耗水量为春季>夏季>秋季>冬季,落叶树种幼苗耗水量为夏季>春季>秋季>冬季。不同土壤干旱水平下,各树种幼苗耗水量均表现为:A>B>C>D。     

芝麻基因雄性不育系的研究

通过群体改良对芝麻雄性不育原始材料进行基因重组，产生了大量优秀变异。用系内连续姊妹交，回效等手段育在敢综合农艺性状良好，不育度为９９％以上，不育株率稳定在５０％左右可供可杂交种生产应用的ｍｓ８６－１不育系。形态学研究证明，所选不育系雄蕊败育彻 底，雌蕊发育正常，具有正常的结籽能力；小孢子败育发生在四分体后的无液泡小孢子期；雄性不育性具有良好的环境稳定性。根据初步的遗传分析推测，不育性可能不是受单隐     

不同农艺措施对旱地谷子水分利用效率的影响

１９８８￣１９９０年在山西省屯留试点进行了不同农艺措施对旱地谷子水分利用效率影响的研究，结果表明，肥料是影响旱地农田水分利用效率的主要因子，其次是品种、密度和播期。     

鸡新城疫油佐剂灭活疫苗的研究

采用ＮＤ Ｌａｓｏｔａ株为种毒，福尔马林为灭活剂，７号白油为佐剂，吐温８０、司本８０为乳化剂，硫柳汞为防腐剂，高压匀浆泵为乳化工具，研制出ＮＤ油佐剂灭活疫苗。其剂型为双相型（Ｗ／Ｏ／Ｗ），呈稀薄乳状液，粒度为１ｕｍ左右，粘度≤１ｓ，通针性好。４￣８℃有效保存期１年。效力≥７０ＰＤ５０，最早产生免疫时间为１２天（１００％保护），生产中常用免疫剂量为２月龄内每只０．５ｍｌ，２月龄以上每只１．０ｍｌ皮下