日光温室内温度变化的研究

根据日光温室的几何特征和结构理论，探讨了日光温室内温度变化状况。同时，对日光温室内环境进行了分析，以便为更好地发挥日光温室效应提供依据。     

林木施肥研究──Ⅰ．肥效理论与基本模型

本文从理论上阐述了肥效与立地条件，土壤理化性状以及养分利用率的相关性，并在此基础上，建立了理论肥效方程和林木施肥模型．同时，结合目标产量和平衡施肥法，确定了林木定量施肥的基本步骤与方法．     

黧蒴栲人工林生长情况的调查与分析

对黧蒴栲人工栽培试验林的生长情况进行了调查与分析,确定了该树种具有适应性强、生长快、成材早、水平根系发达、树冠叶面积大等特点。调查结果表明:试验地造林后第10年黧蒴栲人工林平均材积为136.5 m3/hm2;第15~16年平均材积为304.5 m3/hm2,高于杉木、马尾松、木荷、青周等针、阔叶对照树种。     

退耕还林工程对会泽县农户的影响

截至2005年,会泽县退耕还林(草)面积为1.67万hm2,预计30a后活立木蓄积可增加39万m3.退耕地水土流失明显减少,地表径流比退耕前显著下降.于2006年5月在金钟镇5个有代表性的自然村共抽取了50户退耕农户进行调查,经分析认为,退耕还林(草)工程的实施对农户生产生活的影响主要是:推动了农户土地利用结构调整,使土地利用的可持续性增加;各类农作物种植结构变化不大,农产品产值结构变动较大;提高了农户总体福利水平.提出了保障工程可持性的对策和措施:对剩余劳动力进行技能培训,促进农户收入多元化,建立生态效益补偿制度等.     

重组Taq DNA聚合酶在大肠杆菌中表达条件的优化

以插入重组Taq DNA聚合酶基因的pET-24a表达质粒转化大肠杆菌菌株,转化菌铺平板的最佳量为50至100 μL,可获得转化菌的单菌落,单菌落扩大到200 mL培养量,表达Taq DNA聚合酶,经SDS-PAGE分析,表达带的相对分子质量约为82 ku,最佳表达条件为接种量1/500,工程菌培养到OD600值为1.0开始诱导,以2 mmol/L IPTG诱导8 h,Taq DNA聚合酶可获得较高的表达效率.     

栀子根糖类化合物水提法提取条件研究

采用水提法，对栀子根糖类化合物的提取结果表明：提取温度对糖类化合物的含量有极为显著的影响，其它条件影响较小。通过采用二次通用旋转组合设计方法得出栀子根糖类化合物提取的优化组合是：提取温度为100℃，提取时间为60min，溶剂体积为40ml。     

黑龙江省哈大高速公路中央分隔带绿化树种调查与选择

对哈尔滨至大庆间高速公路现有景观绿化植物种类及中央分隔带立地条件进行实地调查与分析。该路段景观绿化植物6种,其中常绿乔木2种,花灌木4种,植物种类单调,彩化树种缺乏。中央分隔带土层薄,呈中性或偏酸性,土壤速效氮、速效钾和速效磷含量低,土质较差。根据植物的生态学特性及路段的现有条件,结合高速公路绿化要求的特殊性,探讨哈大高速公路中央分隔带绿化树种的选择,为黑龙江省高速公路景观绿化植物的选择、设计、施工和更新改造提供科学依据。     

泰山侧柏林下幼树分布规律及天然更新研究

调查分析了泰山侧柏人工林天然下种幼树的分布规律与郁闭度、坡向和土壤条件的关系。结果表明,郁闭度是影响侧柏林下幼树生存、生长的首要因子,其次是土壤条件和坡向。同时对泰山侧柏人工林天然更新的必要性和可行性进行了讨论。     

Recovery of canopy trees and root collar sprout growth in response to changes in the condition of the parent tree after a fire in a cool-temperate forest

The relationship between the recovery of canopy trees after fire and root collar sprout dynamics was investigated during 1998–2000 in a secondary cool-temperate broad-leaved forest consisting of Quercus mongolica var. grosseserrata and Betula platyphylla var. japonica trees, in northern Hokkaido, Japan, which burned in April 1998. All of the Betula trees that were severely damaged, two-thirds of those slightly damaged, and half of those intact in 1998, died within three growing seasons after the fire. By contrast, half of the Quercus trees that were slightly damaged and half of those severely damaged recovered their foliage, and no slightly damaged or intact trees died during the three growing seasons after the fire. Many Betula trees developed several fruiting bodies of wood-destroying fungi on their stems, irrespective of damage severity. Fungi also infected some of the surviving Quercus, although the crowns tended to recover. Although many sprouting Betula were observed in 1998, the number of sprouts declined rapidly over the study period. Multiple regression analyses showed that the survival and growth of Betula sprouts were positively influenced by the number of sprouts in 1998, damage severity in 1998, and the degree of recover or decline during the study period, and were negatively influenced by parent tree size. On the other hand, a few sprouts of Quercus remained alive. Quercus remained dominant and the dominance of Betula was rapidly reduced after the fire. However, many Betula sprouts remained alive. Stand structure will change drastically for the time being.