Long-chain branched/cyclic alkanes in recent sediment of Lake Fuxian and their environmental implications

Lake Fuxian is a large, deep, and oligotrophic freshwater lake. In recent sediment of this lake, a series of branched and cyclic alkanes, including branched alkanes with one or two quaternary carbon atoms （C2n compounds）, alkylcycloheptane, and alkylcyclohexane, were detected in high abundance. For each homolog of long-chain branched/ cyclic alkanes, molecules with only an odd or even carbon number were present in the sediment. The abundance vari- ation of each compound homolog corresponded to those of other compound homolog in the section, indicating the same origin of these compounds. The concentrations of long-chain branched/cyclic alkanes in the sediment profile exhibited variations similar to those of phytoplankton biomarkers, such as 3-methylJalkanes, short-chain odd carbon n-alkanes, hopene, polyunsaturated fatty acids, phytol, sterols, and long-chain alkyl diols, but slightly different from those of long-chain odd carbon n-alkanes, which are ubiquitous biomarkers for higher plants. Therefore, the Can compounds and long-chain cyclic alkanes in the lake sediment were most likely produced by algae and bacteria in the water, primarily, by the heterotrophic bacteria in the moderately oxygenated waters, which flourishing might be the results of specific water environments in Lake Fuxian.     

The marine red algae of Rodrigues (Mauritius,Indian Ocean)

This paper reports on the red algae of Rodrigues, collected in the framework of the Shoals of Capricorn Programme (10 September to 5 October 2001). In total 68 species are reported, of which 65 represent new records for the island. Although most taxa represent rather common species, which are generally widespread in the Indian and western Pacific Ocean, some are of special interest to algal systematists and biogeographers. Renouxia antillana is reported for the first time for the Indian Ocean. The presence of Renouxia also constitutes the first record of the order Rhodogorgonales for the entire Indian Ocean. A few species have interesting distribution patterns. Halydictyon sp. is restricted in its distribution to South Africa, Mauritius and Australia. Despite these interesting records, the red algal flora of Rodrigues is most remarkable by the absence of several ‘ubiquitous' species.     

小球藻降解苯酚的研究

为利用藻类处理含酚废水，分离培养小球藻作为藻类种源，配置不同浓度苯酚水为受试水样，进行藻类对苯酚的降解实验研究，得出藻类对苯酚吸附降解的适宜浓度是200mg／l以下．所以可以利用藻类处理低浓度含酚水。     

是细菌,还是藻类？

蓝藻早年被认为是藻类植物,在系统学上早已建有蓝藻门,近年来,蓝藻又被确认为原核生物,并与某些细菌十分相似之后,即有许多科学家称之为蓝细菌,并建议将之归于细菌类,这是生物学界近年中发生的一件大事,引起许多人的重视。但到目前为止,此问题尚未获得一致意见,更未采取统一行动。本文简述此事的大体经过,并着重介绍双方各自主张的理论根据和工作方法上有何不同。     

生活污水养鱼池塘的藻类研究

在试验期间共测得31个水样，从试验塘中共发现藻类74种(或亚种、属)，分隶于8个门，以雌藻门竹类最多，硅藻门次之。藻类种群构成随季节而变更；优势种先后为小球藻，卵形隐藻和针状蓝纤维藻，并形成当时的水花。     

河口悬浮物与海洋表层沉积物中藻类可利用颗粒磷的数量研究

运用化学分析和藻类生物测定相结合的方法，对样品中藻类可利用颗粒磷（ＡＡＰＰ）进行定量估算．结果表明，取自厦门湾、泉州湾和黄河口样品中ＡＡＰＰ为６１～１４２ｍｇ／ｋｇ，占样品总磷之８．０％～２０．２％．样品中非磷灰石无机磷是潜在生物可利用磷，磷灰石无机磷则难以被藻类利用．ＡＡＰＰ高低主要与样品物源区气候环境条件、磷的矿物组合、化学存在形态等有关，而与实验藻种无关．推荐用０．１ｍｏｌ／ＬＮａＯＨ～１．０ｍｏｌ／ＬＮａＣｌ（ｗ／ｖ＝１：１，振荡８ｈ），作为样品中ＡＡＰＰ的化学提取剂．     

UV-B辐射增强对藻类影响的研究进展

研究了UV-B辐射对藻类的伤害效应，主要表现为影响藻类的存活率和生长，改变藻类的细胞形态，抑制藻类的光合作用，刺激呼吸作用，改变藻类细胞内的蛋白质、核酸、糖类含量，破坏藻类的种群、群落和生态系统。同时探讨了UV-B辐射对藻类的伤害机制。     

衡水湖自然保护区藻类植物资源初步研究

首次报道了衡水湖国家级湿地自然保护区藻类植物的种类组成、生态类群及常见群落.经初步调查和鉴定,衡水湖国家湿地自然保护区藻类植物共有9门、11纲、22目、31科、59属、119种(含种下分类单位),4种生态类群和8个常见藻类群落.主要类群中以绿藻门最多,共计49种,占保护区藻类总种数的4 1.2%;其次是硅藻门,31种(含1变种)占26.1%;再次是蓝藻门,22种(含1个变型)占18.5%.对衡水湖自然保护区水体环境质量、藻类资源进行了初步评价.     

湖泊藻类生长动力学研究：以镜泊湖为例

本文在湖泊水质监测和实验室模拟的基础上,选择光照强度、温度和营养物三种环境因子做为限制因素研究藻类生长规律,得出了这些因子与藻类生长间的定量关系,并引入了藻类的死亡速率、沉降速率、浮游动物的捕食率、鱼类的捕食串以及水体的物理化学性质等参数,建立了镜湖藻类生长预测模型,该模型具有以下功能:①预测藻类生长的季节变化;②预测藻类在湖泊中的空间分布(深度);③预测湖泊在不同磷负荷下藻类生物量的变化。     

贵州施秉潕阳河藻类植物初步研究

本文报道了采自贵州施秉阳河国家级风景区水域的藻类植物，经初步鉴定计有８门３０科７３属１７３种（包括变种）．其主要群落可以区分为：Ⅰ．浮游藻类群落．包括（１）贫营养型硅藻群落，（２）贫营养到鼓藻──甲藻群落，（３）中富营养型硅藻──盘星藻群落，Ⅱ．附生藻类群落．包括（１）水绵──鞘丝藻群落，（２）水绵──转板藻群落，（３）桥弯藻群落，（４）刚毛藻群落，（５）微孢绿胶藻群落，（６）念珠藻群落，（７）串珠藻群落．风景区水域内藻类种类丰富，Ｓｈａｎｎｏｎ—ｗｅａｖｅｒ指数为３．０７，指示水质清洁．