帽儿山落叶松群落主要树木种群间联结关系的研究

采用2×2 列联表,通过方差分析、χ2检验、Ochiai指数、Dice指数和Jaccard指数对帽儿山落叶松所在群落优势种的种间联结性进行了定量分析。结果表明: 落叶松群落总体间的关联性表现为不显著正关联,在91对种对中46对表现为正关联,其中极显著正关联的种有8对,显著正关联的有4对,极显著负关联的种对有7对。在相对稳定的群落中优势种间可以共同利用群落中的非限制性资源,形成显著的正关联。这种关联性一方面与物种本身的生物学与生态学特性有关,另一方面与群落演替的时间与空间有关。      

THE STUDY ON DETERMINATION OF SELENIUM WITH POTASSIUM BUTYL XANTHATE

INTR0DUCTI0NThemethodof2,3ditalnonaphthalene(DAN)determiningseleniumhashighsensitiv-itVandlittledistUrbanceandisacknowledhedbyanalyticalchemistryworkers,butitwasdifficulttomakeuniversalusebecauseofitShigh-pricedinsboentsandshortofreagent.Weknewthatundertheacidconditionhv-droxylxanthatecouldproducestablecomplexwithselenium(IV).ThiscomplexobviousIyabsorbedlightinultravioletareathroughex-tractingbyorganicsolvent.Weexploredthemethodofbutylxanthatefordeterminingselenium(IV).Itsprinclplewas…     

西伯利亚红松与红松种子形态、种皮显微构造的比较研究

Normal experiment methods and electron microscope scanning technique were used to compare the differences of the seed morphological characteristics and microstructure of the seed coats between Pinus sibidca and P. koraiensis.The purpose of this study is to clarify the dormancy and germination characteristics and mechanism of the seeds of P. sibir-ica. The results showed that the thousand-grain weight of the measured seeds of P. sibidca was only 39.9% and 48.5% of that of P. koraiensis. The weight of outer seed coats of P. sibidca was 54.04% and 52.6% of their whole seed weight, which was lighter than that of P. koraiensis, while the weight of the seed coat of P. koraiensis was of 61.7% of their whole seed weight. Five layers were seen at the cross section of the hard seed coat of P. koraiensis under scanning electron microscope: external seed epidermis layer (external seed coat), epidermis layer, dense lithocyte layer, palisade layer and inner epidermis. There were four layers in the seed coat of P. sibirica : the external epidermis layer, epidermis layer, palisade layer, and inner epidermis.Thickness of outer seed coat of P. sibirica and P.koraiensis was 400 μm and 1 200—1 300 μm respectively. All these characteristics showed a big hindrance and the permeability barrier in the seed coat of P. sibirica, but not stronger than that of P. koraiensis.     

Analysis of Nutrition Composition of Schisandra Fruits

IntroductionSchiSandraisadeciduousvineofMopohaceae.ItsthetStaSteofsWed,sour,bitter,PepPeryandsalty.ItisoneOfthetfadihonalChineseherbalmedicine.Schisan-for(Mopohaceae)hasbeenusedasprecioustonicandastriopntdrugforalleviahngcoughsinceanc1enthme.Modemmedicine…     

喜树茎解剖构造及插条不定根的形成

利用喜树当年生半木质化枝条,研究了喜树茎解剖构造及插穗愈伤组织和不定根发生的情况。结果表明:喜树皮层和髓中存在异细胞,皮层存在环状厚壁组织,但不影响不定根发生,喜树插穗不定根原始体来源于维管形成层和韧皮组织与髓射线交叉部位,愈伤组织不分化为不定根。     

黑龙江产莎草科(Cyperaceae)一新记录种

在撰写《黑龙江植物志》(莎草科)过程中,发现莎草属(Cyperus)的白鳞莎草(Cyperus nipponicus Franch. et Sav.)为黑龙江省新记录种。其主要特征为:植株密集丛生。矮小,一般2—8 cm高。苞片叶状,明显长于花序。花序头状或球形,淡黄绿色,小穗扁平状,披针形或狭卵形,鳞片薄膜质。小坚果约为鳞片长的1/2。柱头2。本种喜生于湿地或江(湖)岸边沙地。     

野生牧草资源—河沙苔草的研究

哈尔滨的松花江流域属于松辽平原的草甸草原草场范畴。由于局部特殊的环境,植物种类较贫乏。但却蕴藏着丰富的牧草资源,河沙苔草仅是其中的一种,本文对河沙苔草的生物量进行了调查,并分析了牧草的化学成分。河沙苔草营养价值很高。叶量丰富是一种优良的天然牧草。     

Reproductive strategies and seeds behavior of Betula platyphylla Suk. Population

Introduction6Birch(BetulaplatyphyllaSuk.)isaphotophilousandbroad-leaftreespecies,whichisdistributedwidelyinthenortheastofChina,especiallyinclearcuttingorburnedforestareasaftertheoriginalvegetationisdamaged(Zhou1986).Birchisjustapioneertreespeciesthroughsecondary-forestsuccession.Sincebirchpopulationoftengrowsrapidlyinalargearea,itusuallyhasagreatamountofseedstorage.Itstimberisanimportantrawmaterialinbuildingmaterials,suchasplywood,veneer,etc..Itsforesightisbroadlyprospectedonexplorationandap…     

大小兴安岭过渡区木本植物群落数量分类与排序

为了科学利用和有效保护植被资源、改善区域生态环境,在群落样方调查基础上,采用双向指示种分析法(TWINSPAN)和典范对应分析(CCA)对大小兴安岭过渡区木本植物群落进行了数量分类和排序。TWINS-PAN分类对大小兴安岭过渡区33个样地划分为7个群落类型:红松—红皮云杉针叶混交群落;落叶松—白桦群落;白桦群落;蒙古栎—山杨群落;水曲柳群落;樟子松—兴安落叶松群落;樟子松群落。33个样方的CCA排序结果反映了植物群落类型与环境梯度之间的关系,表明海拔和土壤状况是影响物种分布分异的最主要环境因子,郁闭度对物种分布分异起次要作用。物种样地与环境因子CCA排序结果是:第一轴与海拔、土壤全氮存在极显著关系,与土壤有机质含量、湿度和群落郁闭度指数存在着较显著的相关关系;第二轴与土壤全磷有显著的相关关系;第三轴则主要反映了土壤含水率的变化。