西藏措勤地区早日垩世双壳类新材料

简述措勤地区双壳类的地层分布及组合特征,描述双壳类化石２０属２０种,其中有６新种。非海相双壳类（Ｉｓｏｄｏｍｅｌｌａ,Ｃｏｓｔｏｃｙｒｅｎａ）的发现具有重要意义。     

广西珍稀濒危植物区系的基本特征

本文在简述广西珍稀濒危植物生态环境和区系组成的同时,重点分析了其植物区系的基本特征。这些特征主要有：区系成分复杂,热带性质明显,特有成分突出,古老成分较多,喜酸成分占优势,绝大部分种类分布在海拔１０００ｍ以下。     

阿尼玛卿山八种柳属植物叶片的形态结构特征研究

对阿尼玛卿山柳属八种植物的叶片进行了形态和解剖研究。观察结果表明：除旱柳外,其余７种均为异面叶;栅栏组织２－３层,细胞排列紧密;有些种的叶上表皮有光滑的角质膜,下表皮为复表皮。表面多有灰白色的粉粒蜡质,气孔不下陷;此外,在叶表皮、叶肉及维管束鞘中皆存在有含单宁或胶质的异细胞。这些特征与高山地区严酷的自然环境条件是相适应的。     

香瓜梨对温度响应的生理特性研究

置于不同温度（５－３５℃）下的香瓜梨幼苗,在１５－３０℃时叶片的光合速度较高。２０℃时的标株叶片具有最高的光合速率,光事电子传递活性,ＰＳＩＩ的光化效率和电子传递的量子效率,叶绿素含量,但细胞膜透性最低。５－１０℃的低温和３５℃的高温明显降低生理参数,且随处理时间的长,其降低程度越明显,解除５℃的低温处理后转自然温度环境（１５－２０℃）中６ｄ,叶片细胞的电解质渗漏降低。     

F344／N－Smu－D大鼠生长发育若干生物学特性的检测

Ｆｉｓｃｈｅｒ３４４大鼠在国外广泛应用于肿瘤研究与慢性毒性试验,八十年代中期引入我国。我们对Ｆ３４４／Ｎ－Ｓｍｕ－Ｄ大鼠的生长发育的若干生物学特性进行了检测。结果表明,该品系大鼠体型较ＳＤ大鼠与Ｗｉｓｔａｒ大鼠小,除睾丸、垂体、肾上腺、乳腺外的大部分器官与组织的自发性肿瘤的发生率相对较低,将Ｆ３４４／Ｎ－Ｓｍｕ－Ｄ大鼠种群与Ｆ３４４／ＤｕＣｒｊ种群比较,在体重、耗食量,血液学与生化学等方面的若干特性差异较大,肿瘤发生率与死亡差别不大。     

广州白云山风景名胜区的植被特点及其林分改造

论述了广州白云山风景名胜区的自然环境和植被演变历史,分析了植被特点和植被演替趋势,提出了林分改造建议。     

Recovery of freshwater marsh vegetation after a saltwater intrusion event

Greenhouse mesocosms of freshwater marsh vegetation were exposed to a simulated saltwater intrusion event followed by a recovery period during which water levels and interstitial water salinity were adjusted over a range of conditions. Virtually all above-ground vegetation, including the three dominant species, Sagittaria lancifolia L., Leersia oryzoides (L.) Swartz, and Panicum hemitomon Schultes, was killed by the initial saltwater intrusion event. P. hemitomon did not recover, but S. lancifolia and L. oryzoides, as well as many of the other species initially present, exhibited some ability to recover depending on post-saltwater intrusion conditions. Increasingly harsh recovery conditions (for freshwater marsh vegetation), including more reduced soil conditions, higher interstitial salinities, and higher interstitial sulfide concentrations were associated with decreased live above-ground biomass and species richness. The effect of elevated salinity on vegetative recovery became more pronounced under flooded conditions. This experiment illustrates that the response of a freshwater marsh community to the long-term disturbance effect of a transient saltwater intrusion event will be strongly influenced by post-intrusion salinity and water levels.     

海甘蓝的初步研究

首次报道了海甘蓝Ｃｒａｍｂｅａｂｙｓｓｉｎｉｃａ在我国的引种栽培情况,并对海甘蓝体细胞染色体进行计数。经过２年的选育,海甘蓝去壳种子的含油量为４４．４７％;芥酸含量高达６２．５０％,比国外报道的结果提高了２．５％－７．５％;未去壳种子的硫甙含量为７１．５１－８２．２１μｍｏｌ／ｇ。理论产量１４８５－５２５０ｋｇ／ｈｍ＾２（９９－３５０ｋｇ／亩）。研究结果表明：在我国海甘蓝有希望成为一种新型的高芥酸     

The ammonia-oxidizing nitrifying population of the River Elbe estuary

Abstract: The ammonia-oxidizing bacterial population of the tidal River Elbe was analysed. In the freshwater section of the river, abundance was generally at a magnitude of 10⁴ cells per g dry weight and 10³ cells per ml in sediments and in water samples, respectively. In the brackish water region, counts decreased drastically with the increase in salinity caused by the low level of abundance of ammonia-oxidizers in the seawater. The contribution of attached ammonia-oxidizers to the total number ranged between 50 and approximately 100%, depending on the respective load with suspended particulate matter (SPM) of the water. The presence of seven distinct species of the genus Nitrosomonas was established by DNA hybridizations. Based on 16S rRNA gene partial sequence analyses, four groups, comprising phylogenetically closely related species, were defined. Dependence of ammonia oxidation on the NH₄Cl concentration, tolerance against increasing salinity and the possession of urease activity were found to be useful ecophysiological characteristics, being in accordance with phylogenetic relationships among the species.     

佛坪自然保护区的鸟类

1981－1996年经野外采集与鉴定,确定佛坪自然保护区已知鸟类211种,隶属于15目40科。其中东洋界种77种,古北界种96种,广布种38种,分别占鸟类总数的37％,45％和18％,呈古北界种稍多于东洋界种的区系特征;在鸟种组成上留鸟114种,夏侯鸟59种,冬候鸟5种,旅鸟33种,分别占鸟类总数的54％,28％,2％和16％,因而鸟类主要由留鸟和夏候鸟组成;与生态适应变幅相关,随季节的变化鸟类分布与迁移变化较大;对26种国家重点保护鸟类分布与数量统计显示,保护区是国家重点保护鸟类的资源宝库,尤其是雉科为鸟类中的优势种资源。