初植密度、间伐对杉木林分优势高生长过程的影响

初植密度、间伐对杉木林分优势高生长过程的影响＊洪玲霞关键词杉木优势高初植密度间伐立地质量是决定林分生长和收获的主要因素之一，在用材林经营与管理中，立地质量定义为“生长在某一地位上既定树种或林分类型林木的生产潜力”。以往的研究表明：许多树种的材积生产潜...     

低温驯化的黑荆树悬浮培养细胞中可溶性蛋白质含量变化*

低温驯化能够诱导黑荆树悬浮培养细胞增强抗冻性，ＬＴ５０从－４．３℃下降到－８．２℃。低温驯化诱可溶性蛋白质含量增加，其增加的时间进程与细胞抗冻性发育呈平行关系。环已亚胺抑制可溶性蛋白质含量增加，同时也抑制细胞抗冻性发育。在低温驯化期不同时间加入环已亚胺抑制抗冻性发育，表明低温驯化１０ｄ后抗浆性发育接近完成。糖对增加驯化细胞中可溶性蛋白质有促进作用，加快增加含量的时间进程，但对最终提高蛋白质含量水平     

白桦胸径和材积生长率相关关系的研究

根据地位指数的大小将白桦林分划分为好、中、差３个类型，通过没类型样地上的解析木资料分析，证明白桦的胸径和材积生长率存在关良好的相关关系。经过优选，建立了不同类型白桦林分的胸径与材积生长率相关模型，并依此编制出白桦一元材积生长率表，为准确预测白桦积生长率提供了理论上的依据。     

半固定沙地樟子松小叶锦鸡儿混交林营造及经营技术研究

在对嫩江沙地樟子松和小叶锦鸡儿人工混交林林分状况和生长指标调查的基础上,采用统计分析方法,探讨了混交林主辅林种间的生长消长关系,结果表明:随着林龄的增长,辅助树种小叶锦鸡儿对主栽树种樟子松的生长发育具有抑制作用,樟子松的生长发育进程减慢,应对小叶锦鸡儿林分进行人工干预,以促进樟子松的生长发育。     

A review of measurement options for multipurpose trees

There is an urgent need to standardize the methods used to assess the growth of multipurpose trees. Most of the standard methods so far described have been developed specifically for use in multilocational trial networks. This paper was prepared for the F/FRED/ICRAF Workshop on MPTS Assessment Methods, held in Thailand in May 1991 to develop internationally-recognised standards for assessment methodology. It critically reviews the methods prescribed by different networks for height and diameter measurement, and for biomass estimation, giving researchers a range of methodological options to consider and re-emphasizing the need, all too often neglected, to define assessment methods clearly and unambiguously.     

黄竹细胞悬浮培养和原生质体分离*

以牡竹属黄竹（ＤｅｎｄｒｏｃａｌａｍｕｓｍｅｍｂｒａｎｃｅｕｓＭｕｎｒｏ）的竹节及无菌苗根颈为外植体，培养于含有５ｍｇ／Ｌ２，４－Ｄ、０．２ｍｇ／ＬＫＴ和２００ｍｇ／ＬＬＨ的ＭＳ培养基上诱导愈伤组织，然后移至相同成份或不同浓度２，４－Ｄ的液体培养基中，进行悬浮培养，以建立分散性良好的悬浮细胞系。利用悬浮细胞和无菌苗叶片经酶解获大量原生质体，其产量分别约为每克鲜重２．５×１０５个和５×１０５个，活力均可达８０％。     

Provenance and progeny results for the tropical white pine, Pinus chiapensis, at five and eight years of age

Eleven provenances and 132 open-pollinated families of Pinus chiapensis were established at six locations in Brazil, Colombia, and South Africa and assessed for height, volume, and forking percent at five and eight years of age. Provenance × site and family × site interactions were examined in a subset of three trials with 38 open-pollinated families in common. Average volume production of P. chiapensis in Colombia and South Africa was 25 m³/ha/yr and 12 m³/ha/yr, respectively, at eight years of age. Provenance and family differences for height and volume were significant at the individual test sites at eight years of age. The La Trinidad (Chiapas) source was the most productive. Forking percent ranged from 3% in South Africa to 38% in San Jose, Colombia at eight years. Provenance × site interactions were significant for forking but not for height and volume. Family × site interactions were significant for height and volume but not for forking. Forty-six percent of the interaction variance between height and location was contributed by only six families. Height/diameter ratios for P. chiapensis were 0.29 and 0.39 in Colombia and South Africa, respectively, and significantly different.     

森林生态系统中林分胸径和树高的Granger因果关系研究

滞后阶数为1时,胸径和树高互为Granger原因,这从理论上证明,建立胸径和树高模型是合理的.当滞后阶数为2时,胸径不再是树高的Granger原因,但树高仍是胸径的Granger原因,两者相比,树高的影响更深远.所以在森林培养时,应更加注重树高,以维持树高对胸径的影响.