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1.
In the estuaries near Falmouth (Cornwall, UK) levels of dissolved copper and zinc are high, due to drainage of copper and tin mines. Phytoplankton species composition in the autumn of 1989 deviated in the metal-contaminated Restronguet Creek from that in other estuarine branches,viz. Fal, Tresillian and Percuil. In the riverine part of Restronguet Creek (Carnon River)Euglena mutabilis, known as an acidophilic (pH 3) metal-resistant flagellate, occurred at micromolar Cu and Zn, whereas in the clean riversChlamydomonas sp. andOocystis sp. occurred at nanomolar Cu and Zn. An ordination analysis revealed the following patterns in Cu, Zn and phytoplankton species composition in the poly- and euhaline waters. Seston-bound Zn and dissolved Zn were in equilibrium,Katodinium rotundatum is Zn-tolerant, andSkeletonema costatum occurred in water with high contents of Cu in seston. However, none of the variables in these patterns correlated at a significant level (p>0.05). The results show that algae-metal interactions are complicated, and that statistical correlations foundin situ need experimental verification.Communication no. 542 of the Delta Institute for Hydrobiological Research.  相似文献   
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Samples of microplankton and larger nanoplankton (5 to 200 m) are preserved with a combination of Lugol's solution and DaFano's fixative. Organisms are then settled on a gelatin-coated slide, dried and embedded in 40 percent glycerin. Counting and sizing is performed under a microscope using a drawing tube, which facilitates measuring the organisms with a microcomputer-interfaced caliper. An interactive computer program, written in BASIC, allows for estimating the volumes of cells in up to 40 shape/species categories. The program then saves data on a disk, retrieves them, and calculates the results either for individual species (abundance, biomass, and mean cell volume) or as a pooled size spectrum of all organisms measured.  相似文献   
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贵州高原红枫湖水库浮游植物功能分组及其时空分布特征   总被引:13,自引:0,他引:13  
黄国佳  李秋华  陈椽  商立海  张垒  欧滕  高廷进  李钥  邓龙 《生态学报》2015,35(17):5573-5584
为了解贵州高原水源红枫湖水库的浮游植物功能类群及其时空分布特征,于2012年至2013年枯水期(11月)、平水期(4月)、丰水期(7月)对红枫湖浮游植物与水体进行分层采样分析。研究结果表明,水库浮游植物可分为25个功能群,其中S1、F、J、B、D、S2、Y、LM是红枫湖主要代表性功能群,而W1、A、W2、K、X3出现频率较低,主要功能群生境特征都适应于中富营养水体,S1适应于透明度较低、混合程度较高的中富营养水体,F适应于深层混合的中至富营养湖泊,J适应于混合的高富营养浅水水体,B对分层敏感适应于中营养水体;各采样点主要浮游植物功能群季节变化大体相同,枯水期、平水期各采样点功能群较少,丰水期功能群最为丰富;水温是影响红枫湖浮游植物功能类群分布变化的主要因子;浮游植物生长策略变化规律为:枯水期CR/R/S策略藻种→平水期R/CR/CS策略藻种→丰水期R/CR/CRS/C策略藻种,水体浮游植物优势功能群在物质供给、能量输入均较理想的条件下能充分生长,随着能量限制程度的增加而较其他类群更具耐受性;通过浮游植物功能群与水体环境相互关系可以得出:红枫湖水体处于中富营养状态。  相似文献   
6.
Due to the intensive mixing polymictic lakes should be homogenous. However, morphometric diversity and high water dynamics contribute to the differentiation of many parameters in various areas of the lakes. This study analyzes both phytoplankton and zooplankton to assess differences in water quality along the north–south axis of the longest lake in Poland. New phytoplankton indicators were applied for determining the lake's ecological status: the Q index based on functional groups and the PMPL (Phytoplankton Metric for Polish Lakes) index based on phytoplankton biomass. TSIROT index (Rotifer Trophic State Index), which comprises the percentage of species indicating a high trophic state in the indicatory group and the percentage of bacteriovorus in the Rotifera population, was used for zooplankton analysis.TP content was different at different sites – we observed its gradual increase from the south to the north. Spatial variation of phosphorus did not considerably affect plankton diversity. The phytoplankton was dominated by Oscillatoriales, typical of shallow, well-mixed eutrophic lakes. The ecological status of the lake based on the EQR (Ecological Quality Ratio) was poor or moderate. The zooplankton was dominated by rotifers (at almost all sites), which indicates a eutrophic state of the lake. The values of phytoplankton indices at the studied sites did not differ considerably; the differences resulted more from local conditions such as the contaminant inflow and the macrophyte development than water dynamics.We have demonstrated that in the lake dominated by filamentous Cyanobacteria the ecological status should be determined according to the PMPL index or other indices dependent on the dominant Cyanobacteria species. Since the Q index does not include the functional group S1, the results can lead to the false conclusion that water quality improves with an increased amount of phytoplankton. The high abundance of Cyanobacteria in the lake may have contributed to the poor growth of rotifers.  相似文献   
7.
The least squares estimator of a linear regression coefficient L will give an overall expression for the change in with x. In fresh water ecology, however, subgroups, % MathType!MTEF!2!1!+-% feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn% hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr% 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9% vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x% fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaamiuaSGaci% 4Aaaaa!37BE!\[P\operatorname{k}\], of a parent population may have slopes which differ from the overall slope, L. By constructing frequency histograms for the set of angles: Arctang % MathType!MTEF!2!1!+-% feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn% hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr% 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9% vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x% fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaci4uaSGaam% yAaiaadQgaaaa!38AE!\[\operatorname{S} ij\],% MathType!MTEF!2!1!+-% feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn% hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr% 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9% vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x% fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaci4uaSGaam% yAaiaadQgaaaa!38AE!\[\operatorname{S} ij\]= para sa y and x% MathType!MTEF!2!1!+-% feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn% hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr% 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9% vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x% fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaaiikaiaadM% faliaadMgakiabgkHiTiaadMfaliaadQgakiaacMcacaGGVaGaaiik% aiaadIhaliaadMgakiabgkHiTiaadIhaliaadQgakiaacMcaaaa!42F0!\[(Yi - Yj)/(xi - xj)\], i < j, % MathType!MTEF!2!1!+-% feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn% hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr% 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9% vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x% fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaamiEaSGaam% yAaOGaeyiyIKRaamiEaSGaamOAaaaa!3BAB!\[xi \ne xj\], peaks in the distribution may be identified and related to ecological phenomenon. To identify peaks we fit Gaussian distributions to the frequency histograms. For a set consisting of 142 observations of chlorophyll-a and total phosphorus (nutrient) concentrations (TP) from 16 lakes we found four Gaussian peaks corresponding to four subgroups, % MathType!MTEF!2!1!+-% feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn% hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr% 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9% vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x% fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaamiuaSGaci% 4Aaaaa!37BE!\[P\operatorname{k}\]k = 1,4. One group identified a response of chl-a to changes in TP which correspond approximately to the average slope found by least square regression (the slope was 0.49). The second group consisted of steeper response than the average (1.28). A third group showed that there is an enhanced proportion of cases where chl-a does not respond to TP (zero slope, all the three deep lakes > 10 m, included in the date set contributed to this group). The size of the last group, spanning a wide range of slopes, suggested that about 30% of the inter annual changes in chl-a is unrelated to TP. The results are compared to result obtained by simple least squares regression and to the Theil non-parametric slope estimator.  相似文献   
8.
Phytoplankton primary production, nutrient concentrations and turbidity were monitored at three stations in the Oosterschelde during 1980–1984 as part of an ecosystem study.From comparisons of dissolved nutrient ratios with the nutrient requirements of phytoplankton, and of ambient nutrient concentrations with half-saturation constants for nutrient uptake by natural phytoplankton populations it was concluded that silicate was a limiting nutrient for diatoms after the spring bloom until the end of the summer. Dissolved inorganic nitrogen and phosphate were not considered to be limiting to phytoplankton growth.In general, the phytoplankton growing season started during the first fortnight of April and ended at the end of September. Column production in the whole Oosterschelde varied between 201 and 540 g C m–2 yr–1 and was, on average, 25% higher in the western part than in the eastern part. Basin production in the Oosterschelde varied between 120 and 466 g C m–2 yr–1 and was, on average, 55% higher in the western part than in the eastern part; this difference could be explained by differences in the ratio of euphotic depth to mean depth of the compartments.Estimated carbon-specific growth rates in the eastern part varied between < 0.1 and 3 d–1 and in the western part between < 0.1 and 1 d–1. This difference could be explained by the great differences in depth of the compartments. Carbon-specific growth rates are discussed in relation to phytoplankton loss rates. It is suggested that in the eastern part sedimentation must be an important sink for phytoplankton.Communication no. 473 of the Delta Institute for Hydrobiological Research, Yerseke, The Netherlands.  相似文献   
9.
基于2003-2012年太湖竺山湖和西部沿岸区水体理化指标与浮游植物丰度的逐月监测数据,分析了两个湖区氮磷营养盐状态和浮游植物丰度以及浮游植物主要类群的年际变化趋势及季节变化特征,探讨了浮游植物群落变化与水温及营养盐指标间的关系。结果表明:10年间两个湖区氮磷营养盐浓度总体呈下降趋势,以竺山湖TN、NH3-N浓度和西部沿岸区NO3-N浓度下降最为显著;浮游植物丰度总体呈上升趋势,蓝藻在群落结构中日益占据绝对优势;季节变化上,氮营养盐浓度表现为春冬季节高于夏秋季节,TP浓度和浮游植物丰度呈相反的变化趋势。Pearson相关分析显示,水温、NH3-N浓度和TN/TP是影响蓝藻丰度及其在浮游植物群落中所占比例的主要因素。在温度和营养盐结构的共同作用下,10年间两个湖区蓝藻水华暴发时间逐渐提前,而消退时间逐渐滞后,水华持续时间逐年上升。在全球变暖背景下,太湖水华治理需执行更加严格的氮磷限制阈值,且在重污染的西北湖区控磷依然是关键。  相似文献   
10.
Negative correlations between aluminum and planktonic algal abundance have been reported in acidic lakes. Natural assemblages of phytoplankton from a low-pH, low-Al lake (Franklin Lake, WI) were grown in semi-continuous cultures consisting of four treatments at pH 5.7 with 0.0, 50, 100, and 200 μg Al L−1 and one treatment at pH 4.7 with no Al added. Asterionella ralfsii var. americana (a common diatom plankter in acidic lakes) grew well at both pH 4.7 and 5.7 when no Al was added but declined in all other treatments and so may be useful as an indicator of acidic, low monomeric-Al conditions. Other common plankters that showed this pattern included: Arthrodesmus indentatus, Ar. octocornus, Ar. quiriferus, Staurastrum arachne var. curvatum, S. longipes var. contractum, and S. pentacerum. Common taxa showing no toxic effects of Al were Dinobryon bavaricum, Peridinium limbatum, Stenokalyx monilifera, Elaktothrix sp. and Oedogonium sp. We hypothesize that metal toxicity as a pulse at spring snowmelt could dramatically change algal succession in moderately acidic lakes. The experimental results agreed well with field observations. These types of experiments are useful for predicting the responses of natural phytoplankton communities to increases in Al concentration.  相似文献   
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