The generation identification and process of digenesis of Korean pine forest

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Promotion of the population growth of pinewood nematode in 4-month-old Japanese black pine seedlings by pretreatment with simulated acid rain

Simulated acid rain (SAR) at three pH levels (pH 4, 3, 2) was applied to only the top or both the top and roots of 4-month-old Japanese black pine seedlings repeatedly for two months. Then the seedlings were inoculated with a virulent isolate (S10) of pinewood nematode,Bursaphelenchus xylophilus. The exposure to SAR at any level did not kill the seedlings. When inoculated with nematodes, however, the nematode population build-up was significantly higher in the seedlings pretreated with SAR at any level than in the control at the 7th and 17th day after inoculation, and subsequent disease symptom development was also significantly accelerated by the exposure to SAR at pH 2 and 3. This result indicates that even acid rain at pH 4 has the potential for promoting population growth of pinewood nematodes in 4-month-old Japanese black pine seedlings.     

Genetic improvement in pine wilt disease resistance inPinus thunbergii: The effectiveness of pre-screening with an artificial inoculation at the nursery

Open pollinated progenies from 15 clones of Japanese black pine (Pinus thunbergii), that had been selected for their tolerance to pine wilt disease, were tested by artificial inoculation with pine wood nematode for six years at a nursery of Kyushu Regional Breeding Office. Family variations in the respective year were all significant. An analysis of variance across the six years’ tests confirmed highly significant effect of year and of families; however, the year by family interaction was significant also. Phenotypic and genetic variances estimated from each year’s result were fitted to a quadratic regression using their mean survival ratio as an independent variable. The variances were greatest at around 0.5 of the mean survival ratio. Estimated heritability showed a similar trend of change, whereas the peak of the expected amount of improvement shifted toward the lower survival range: around 0.4, where a greater selection differential was anticipated. It was concluded that a useful amount of genetic improvement that may be reduced by 30% due to the interaction, would be expected by prescreening seedlings where the mean survival ratio after inoculation was around 0.25 to 0.6.     

Guidelines for Managing Wildlife Habitats in Southwestern Ponderosa Pine Forests of the United States

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不同抚育方式对火炬松中幼林生长的影响

在广东省翁源县江尾镇低丘赤红壤上，对７年生火炬松人工林的抚育强度、季节和次数进行了研究。２年试验观测，协方差分析结果表明：抚育前的本底生长量对抚育后２年的生长量有极显著的影响。剔除本底生长量的差异后，穴垦抚育的胸径生长量、单株材积生长量和单位面积蓄积量均显著或较显著高于全垦和带垦抚育，而全垦和带垦抚育间生长量的差异则不明显；抚育季节、次数的不同以及其与抚育强度的交互作用对火炬松生长的影响不明显     

旅游对清西陵古油松林节肢动物群落结构及其多样性的影响

2005年5~10月对清西陵古油松林的节肢动物群落进行了调查,分析了古油松林节肢动物群落组成结构和多样性,讨论了旅游干扰对古油松林节肢动物群落的影响。结果表明,旅游活动对古油松林节肢动物群落的结构和多样性有显著影响,从而为保护和合理利用古油松资源提供理论依据。     

晋东南石灰岩山地油松人工林立地类型划分及评价

利用１１８块野外标准地资料，对晋东南石灰岩山地油松人工林进行了立地类型划分及生长评价。经分析坡向、海拔、土层厚度为影响林木生长的主导立地因子，３个主导立地因子共构成２４个组合立地，每个组合立地可视为一个立地类型，用最优分割法将２４个立地类型划分为４个立地类型组。在优势木与平均木树高相关分析的基础上，以椽材林木为标准。对４个立地类型组进行了林木生长评价与预测。     

松树截根菌根化育苗和造林的研究*

根据苗木根系分泌物能促进菌根真菌萌发和生长的原理，结合我国林业育苗的特点，提出了松树幼苗截根与人工接种菌根真菌结合的育苗方式。结果表明，截根菌根化育苗在促进根系发育和菌根形成，加速苗木生长，提高苗木生物量、苗木质量和产苗量等方面都有显著优势，苗木的侧根数、侧根总长、苗木菌根化率、吸收根菌根化率、苗高、地径、鲜重、干重分别提高２０．０％～９６０．０％、５６．２％～３８９．５％、０．０％～４００．０％、５６．２％～１７９２．０％、２２．３％～１７９．３％、３１．２％～２５３．８％、３３．３％～９１８．２％和２１．８％～７４０．０％，苗木成活率和Ⅰ级苗分别提高９．０％～２２．１％和４９．３％～１５０．０％，Ⅱ、Ⅲ级苗和等外苗分别降低４０．６％～７７．３％、６１．６％～８８．５％和８２．５％～１００．０％。利用截根菌根化苗木造林，提高成活保存率５．５％～４６．０％，并促进幼树生长，树高、地径和材积指数分别增加１３．０％～５６．４％、２５．５％～６１．７％和８７．８％～４５０．０％。效益分析证明，截根菌根化育苗具有明显的经济效益和社会效益，仅苗期可定量计算的增收（节支）总额可达４４６６２元／ｈｍ２。     

我国南方湿地松木材物理力学性质变异初探

我国南方五省区湿地松木材的密度、晚材率和各项力学强度,随纬度的增加,呈递减状态。纬度与气干容重之间的直线回归方程为:G=1.28—0.027L,相关系数r=0.984.产生此现象的主要原因是,木材的管胞宽度和厚度随着纬度的增加逐渐变窄、变薄。产地的年平均气温和年降水量对湿地松树木的年轮宽度和晚材带宽度影响较大;年轮和晚材带的平均宽度随产地自北向南依次增加,随着山地海拔的升高而减小。     

松花粉工艺处理对防控印度谷螟的效果

印度谷螟是松花粉的重要仓储害虫,为有效控制仓储害虫,确保产品质量安全,进行了干燥、过筛、灭菌及破壁等松花粉产品主要工艺过程防控印度谷螟的试验。结果表明:在松花粉产品加工流程中,采用180目以上筛网过筛,49 ℃、120 min加温干燥,12 kGy ⁶⁰Coγ辐照灭菌,机械破壁或压片成型,7 g·m^-3、6.5 h硫酰氟熏蒸或-8 ℃、24 h冷冻贮藏等任一工艺处理,都能防杀印度谷螟卵或幼虫。各措施组合应用能有效防控印度谷螟侵入或危害,且经济、实用和安全。