温度、光照和pH之间的相互关系对光合细菌生长的影响   总被引：8，自引：0，他引：8  

王立超  连岩  张志新 《海洋湖沼通报》1997,(4):28-31

我们于1996年3月至8月，在光合细菌培养期间，对光合细菌培养条件的最适温度、光照和pH进行较系统的研究与观察，发现了温度、光照和pH值同时影响着光合细菌的生长。而且温度、光照、pH值之间是相互制约的，温度与光照的强弱应是对立统一的。总结出光合细菌生长的最适条件应是互应的。经试验得出光合细菌生长的最适条件：（1）温度为15—20℃，光照度为30000—5000Lx，培养基pH为7．0。（2）温度为25—30℃时，光照为3000—500LX，其培养基pH为7．0。  相似文献   

Shallow lake trophic status linked to late Holocene climate and human impacts   总被引：1，自引：1，他引：0  

Matthew N. Waters  Michael F. Piehler  Antonio B. Rodriguez  Joseph M. Smoak  Thomas S. Bianchi 《Journal of Paleolimnology》2009,42(1):51-64

Lake Mattamuskeet, North Carolina, USA is a large (162 km²) and shallow (mean depth = 1 m) coastal lake, which was significantly modified to support agricultural activities following European settlement in 1850. Paleolimnological proxies measured on a 400-cm sediment core collected from Lake Mattamuskeet reveal shifts in organic matter input and primary producer community structure in response to climatic and human impacts on the lake during the late Holocene. Stratigraphic changes in organic matter content, nutrients, metals, lignin phenols and photosynthetic pigments were used to divide the sediment core into three intervals. Interval I includes sediment deposited between A.D. 360–1584 and indicates a clear-water, sand-bottom state with low algal abundance. In addition, the lake catchment area experienced two significant fires during this interval that were recorded as charcoal layers in the core around A.D. 360 and A.D. 1435 (calibrated ¹⁴C AMS dates). Trophic structure changed with the onset of Interval II (A.D. 1584–1860) when total algal abundance increased, and the primary producer community was comprised primarily of diatoms, chrysophytes, cryptophytes and cyanobacteria. During this interval there was also an increase in terrestrial organic material input into the lake as well as a shift in plant type from woody gymnosperms to non-woody angiosperms as determined from lignin data. Sediment deposited in Lake Mattamuskeet following European settlement (Interval III, A.D. 1860-present) suggests a dramatic increase in organic-matter deposition, metals, primary-producer abundance and the onset of cyanobacterial dominance. Sedimentary evidence indicates that shallow-water primary producers can respond rapidly to climate change and human development.  相似文献   

光合细菌类胡萝卜素的研究   总被引：6，自引：0，他引：6  

牟海津  王宇新 《海洋湖沼通报》1998,(4):32-38

本文对光合细菌的培养条件进行研究后,发现适当增加菌种的接种量和光照强度,以及微好氧培养,均会提高光合细菌的生长速度,采用石油醚－甲醇抽提法对菌体中的类胡萝卜素进行提取,最终获得的类胡萝卜素产量为１７０ｍｇ／Ｌ培养液,菌体湿重为７．５ｇ／Ｌ培养液。对所获得的色素的部分性质进行分析,通过薄层层析发现其中含有三种组分,该色素对酸较为稳定,对热的稳定性则较差。在室内光线条件下,具有一定的稳定性,可以较长时  相似文献   

不同生育期水分胁迫对玉米光合特性的影响   总被引：6，自引：0，他引：6  

刘帆  申双和  李永秀  李丽  邹学智 《气象科学》2013,33(4):378-383

利用遮雨棚以夏玉米为对象进行水分胁迫大田试验,通过分析玉米叶片光合测量数据,研究不同生育期水分胁迫对玉米光合特性的影响,为定量分析不同水分胁迫程度对玉米生育的可能机理提供数据和初步的理论支持.结果表明:土壤水分下降会使玉米叶片的光合速率(Pn)、气孔导度(Gs)、蒸腾速率(Tr)降低,而胞间CO2浓度(Ci)和水分利用效率(WUE)会增加;Pn随着光照强度的增加而增加,且随着水分胁迫强度增强,Pn增加速率降低;干旱胁迫会改变Pn、Tr日变化规律,并且对拔节期光合作用的抑制小于成熟期;WUE与Pn存在极显著的正相关关系,与Tr、Ci及Gs存在显著的负相关关系.  相似文献   

Effects of a thermal discharge from a nuclear power plant on phytoplankton and periphyton in subtropical coastal waters   总被引：2，自引：0，他引：2  

Yi-Li Chuang  Hsiao-Hui Yang  Hsing-Juh Lin   《Journal of Sea Research》2009,61(4):197-205

Effects of elevated water temperatures and residual chlorine from a thermal discharge at a coastal nuclear power plant on the biomass and productivity of periphyton and phytoplankton were determined in subtropical Taiwan. Phytoplankton chlorophyll a, but not productivity, was significantly lower in the outlet region than in the intake region. Periphyton chlorophyll a was significantly greater in the outlet region than in the intake region. Nevertheless, periphyton productivity was negatively correlated with water temperature in the outlet region. A distinct difference in periphyton community composition was also detected between the two regions. Chlorination experiments showed that a chlorine concentration of 0.2 ppm greatly suppressed phytoplankton productivity, regardless of whether the water temperature was elevated or not. However, periphyton productivity was little influenced by a chlorine concentration of < 0.5 ppm. Our results suggest that phytoplankton productivity was greatly affected by residual chlorine, but periphyton productivity was more affected by elevated water temperatures.  相似文献   

Spatial and temporal variations of <Emphasis Type="Italic">Synechococcus</Emphasis> and picoeukaryotes in the Taiwan Strait,China     

黄邦钦  林学举  洪华生 《中国海洋湖沼学报》2009,27(1):22-30

The size-fractionated phytoplankton biomass, and the spatial and temporal variations in abundance of Synechococcus (SYN) and picoeukaryotes (PEUK) were measured in the Taiwan Strait during three cruises (August 1997, February–March 1998, and August 1998). The results show that picophytoplankton and nanophytoplankton dominate the phytoplankton biomass, in average of 38% and 40%, respectively. SYN and PEUK varied over time in abundance and carbon biomass, greater in summer than in winter, in range of (7.70–209.2)×10⁶ and (0.75–15.4)×10⁶ cells/cm² in the abundance, and 1.93–52.3 and 1.57–32.4 μgC/cm² in the carbon biomass, for SYN and PEUK, respectively. The horizontal distributions of both groups were diurnal but heterogeneous in abundance, depending on the groups and layer of depths. Temperature is the key controlling factor for picophytoplankton distribution (especially in winter) in the Strait. Supported by Natural Science Foundation of China (No.40730846; 40521003)  相似文献   

Spatial and temporal variations of Synechococcus and picoeukaryotes in the Taiwan Strait,China     

黄邦钦  林学举  洪华生 《中国海洋湖沼学报》2009,27(1)

The size-fractionated phytoplankton biomass, and the spatial and temporal variations in abundance of Synechococcus (SYN) and picoeukaryotes (PEUK) were measured in the Taiwan Strait during three cruises (August 1997, February-March 1998, and August 1998). The results show that picophytoplankton and nanophytoplankton dominate the phytoplankton biomass, in average of 38% and 40%, respectively. SYN and PEUK varied over time in abundance and carbon biomass, greater in summer than in winter, in range of (7.70–20...  相似文献   

海洋微微型真核生物分子多样性的研究方法     

汪岷  江雪娇 《中国海洋大学学报(自然科学版)》2009,39(4)

微微型真核生物在海洋中广泛存在,是初级生产力的重要贡献者,也是微食物环的重要组成部分.由于微微型真核生物形体微小且不同种类缺乏明显形态学特点,故而难以利用电镜等传统方法精确研究其系统发生关系和种类组成.运用分子生物学技术直接对微微型真核生物种类组成进行研究已成为微微型真核生物多样性研究的重要方法.本文概述了目前世界范围内的微微型真核生物分子多样性研究进展以及我国在该领域中的研究状况.综述了微微型真核生物分子多样性研究中常用的靶标基因,包括18S rDNA和ITS序列等真核生物保守基因及psbA和rbcL等功能基因;常用的分子生物学方法,如克隆文库构建、DGGE/TGGE、PCR-RFLP/T-RFLP、FISH、宏基因组等;以及目前研究方法中存在的一些问题.  相似文献   

Distributions of picophytoplankton and phytoplankton pigments along a salinity gradient in the Changjiang River Estuary,China     

Baoli Wang  Congqiang Liu  Fushun Wang  Siliang Li  Sivaji Patra 《中国海洋大学学报(英文版)》2014,13(4):621-627

We investigated the abundance of different picophytoplankton groups and the phytoplankton pigment ratio in relation to environmental factors such as nutrients and suspended solids along a salinity gradient in the Changjiang River Estuary. The average numbers of Synechococcus spp.(Syn) and picoeukaryotes(Euk) were(2.7 ±5.1) ×103 and(1.1±1.4) ×103 cells m L-1, respectively. Prochlorococcus spp.(Pro) was only found in the high-salinity brackish water with the concentration of 3.0×103 cells m L-1. Syn and Euk numbers both tended to increase offshore and Syn showed a larger variation in cell abundance than Euk. The contribution of picophytoplankton to total phytoplankton biomass increased with increasing salinity and decreasing nutrient concentrations from the estuary to the open ocean. The response of different picophytoplankton groups to environmental variables was different. Water temperature was more important in its control over Euk than over Syn, while nutrients were more important in their influence over Syn than over Euk. Phytoplankton pigment ratios were different in the three different ecological zones along the salinity gradient(i.e., freshwater zone with 0-5 range, fresh and saline water mixing zone with 5-20 range, and high-salinity brackish water zone with 20-32 range), where three different phytoplankton communities were discovered, suggesting that phytoplankton pigment ratios can be considered as a complementary indicator of phytoplankton community structure in the Changjiang River Estuary.  相似文献   

祁连山海北高寒草甸地区植物生长期的光合有效辐射特征   总被引：13，自引：3，他引：13  

李英年  周华坤 《高原气象》2002,21(1):90-95

分析了祁连山海北高寒草甸地区 1998年植物生长期内光合有效辐射 (PAR)的日、季节变化特征。结果表明 :PAR日变化与太阳总辐射 (Eg)日变化趋势一致 ,表现为单峰型变化过程 ,日总量最大可达 11.7MJ·m-2 左右。植物生长期内的 4月下旬～ 9月中旬季节变化较为复杂 ,雨季来临之前的 4～ 6月较高 ,其它时间较低 ,旬平均最高在 5月达 85 .2 3MJ·m-2 。PAR在Eg中所占的比例 (η)晴天状况下日平均在 0 .36～ 0 .41之间 ,阴天稍高 ,植物生长期内 η的旬平均在 0 .32～ 0 .43之间。分析还表明 ,PAR与Eg日总量具有很好的正相关关系 ,从而可依Eg的变化量来估算PAR。同时计算表明 ,海北高寒草甸地区植物群落对PAR的光能利用率为 0 .5 8%左右  相似文献