直干桉、蓝桉无性系多点测定的初步分析

经方差分析后发现，３个试验点的直干桉、蓝桉无性测定林在１９９４年７月以前造的，其处理间的生长差异显著或极显著，直干桉的生长差异比蓝桉更大。将造林时的苗高作协方差分析，用回归系数调整树高后，大部分无性系的树高都超过对照。对无性系与环境的交互作用初步结果的分析表明，多数地点、地点ｘ无性系的差异显著。以实测值（并非调整值）为难，选出了材积超过对照２５％的直干桉无性系７个，蓝桉无性系６个，最好无性系的材积分别为对照的２８８％和２５６％。     

柚木(Tectona grandis)无性系繁育及造林技术

柚木为马鞭草科柚木属植物,是世界上最珍贵的用材树种之一。文章介绍了柚木的生物学特性、无性繁殖即组培技术要点以及造林技术,论述了柚木在我省的推广前景。     

纵带球须剌蛾的生物学特性及其防治

纵带球须刺蛾是多种农林作物的害虫。在广州1年发生1～3代,以老熟幼虫在土中茧内越冬,幼虫一般为7～8龄,幼虫感染核多角体病毒后,常成为流行病,死亡率可达90%以上。进行防治试验表明,90%敌百虫晶体40000倍液、80%敌敌畏乳剂100000倍液和50%杀螟松乳剂100000倍液等,以及2.3×10~(5-7)浓度的核多角体病毒,均对幼虫有较好的毒杀效果。     

浙江淳安新安江开发公司封山育林效益研究

浙江省淳安县新安江开发公司所属16个国营林场22475.53hm~3荒山迹地,封山育林30年,现有天然次生林总蓄积量135万m~3,年总生长率8.07％,活立木直接经济价值2.25亿元。到1987年止公司已获中间利用净收入2135万元。近20年累计天然次生林比无林地多涵蓄水10亿m~3,每年进入水库的泥沙量减少80％,对调节水库水源、延长发电年限、纯洁水质都起到良好作用。公司长期实施的5项管护技术,把封山育林提高到科学经营水平,在千岛湖区成功地建立了森林生态屏障。     

农药混配室内毒力测定的一种实验技术

本文介绍了一种用于测定杀菌剂之间相互作用的实验设计，笔者借且作杀虫剂混配室内毒力测定，该实验设计具有覆盖面宽，成功率高，工作量小等特点。     

辽西北困难立地造林有关建议

辽西北地区造林成效很低究其根源,概括起来,困难立地造林主要问题也不少。     

浅谈林业生产中的造林及抚育技术

在林业生产的过程中,采用正确、合理的造林技术和抚育技术,能够提高造林成活率,确保林木健康生长,并在短时间内构建完善的林分结构。而科学的抚育管理,又能进一步挖掘林业发展潜力,提升林地质量和产量,为林业发展创造更多的空间。同时做好造林和森林抚育工作,能够有效地促进林业科学发展,更好地应对全球气候变化的挑战。     

不同药物防治羔羊奶结症临床效果分析

为寻找羔羊奶结症的有效防治药物，将筛选出的5组药物用于羔羊奶结症的防治试验？结果表明，第l组药物“消维康”口服液对于减少羔羊奶结的发生有明显作用，第2组药物四仙莪棱香附散治疗羔羊奶结效果最佳．     

不同马尾松杂种F_1代早期生长的比较

在福建省大田梅林国有林场连续4年调查火炬松×马尾松、湿地松×马尾松杂种F1代以及马尾松纯种苗木造林早期生长情况,结果表明：幼树存活率在造林4年后趋于稳定,且火炬松×马尾松杂种F1存活率高于湿地松×马尾松。火炬松×马尾松、湿地松×马尾松杂种F1代和马尾松纯种3个树种4年生以下（含4年生）幼树的平均地径（胸径）、抽梢、树高生长总体大小依次为：火炬松×马尾松〉湿地松×马尾松〉马尾松纯种,但3个树种间差异均不显著。4年生（48个月）幼树火炬松×马尾松杂种F1代和马尾松纯种平均树高差异显著;50个月生幼树火炬松×马尾松杂种F1代和马尾松纯种间、湿地松×马尾松杂种F1代与马尾松纯种间差异显著,但火炬松×马尾松与湿地松×马尾松间差异不显著。     

Sugar beet rotation effects on soil organic matter and calculated humus balance in Central Germany

In order to quantify the influence of land use systems on the level of soil organic matter (SOM) to develop recommendations, long-term field studies are essential. Based on a crop rotation experiment which commenced in 1970, this paper investigated the impact of crop rotations involving increased proportions of sugar beet on SOM content. To this end, soil samples were taken in 2010 and 2012 from the following crop rotation sequences: sugar beet–sugar beet–winter wheat–winter wheat (SB–SB–WW–WW = 50%), sugar beet–sugar beet–sugar beet–winter wheat (SB–SB–SB–WW = 75%), sugar beet–grain maize (SB–GM = 50%) and sugar beet-monoculture (SB = 100%); these were analysed in terms of total organic carbon (TOC) and microbial biomass carbon (MBC) content, MBC/TOC ratio and the TOC stocks per hectare. In addition, humus balances were created (using the software REPRO, reference period 12 years) in order to calculate how well the soil was supplied with organic matter. In the field experiment, harvest by-products (WW and GM straw as well as SB leaves) were removed. After 41 years, no statistically significant differences were measured between the crop rotations for the parameters TOC, MBC, MBC/TOC ratio and the TOC stock per hectare. However, the calculated humus balance was significantly affected by the crop rotation. The calculated humus balance became increasingly negative in the order SB–SB–WW–WW, SB–SB–SB–WW, SB monoculture and SB–GM, and correlated with the soil parameters. The calculated humus balances for the reference period did not reflect the actual demand for organic matter by the crop rotations, but instead overestimated it.