云南高原湖泊沿岸带底栖藻类群落的分布

对云南6个高原湖泊沿岸带底栖藻类的群落结构、现存量等进行了调查,研究期间发现底栖藻类群落主要由绿藻门的刚毛藻(Cladophora spp.)和硅藻门的一些附植种类组成,除硅藻群落在泸沽湖占优势外,其它湖泊中绿藻群落的相对比率高于硅藻。底栖藻类现存量(chl a)以星云湖最高(24μg·cm-2);底栖硅藻密度以泸沽湖的鸟岛最高,为9.3×106cells·cm-2。分析不同湖泊底栖硅藻的群落结构发现:底栖硅藻Epithemia sorex和Cocconeis klamathensis分别是泸沽湖和抚仙湖

着生刚毛藻处理富营养化湖泊水

分别研究了室内和露天条件下在鹅卵石上着生的刚毛藻Cladophora oligoclona对富营养化湖水中氮(N)和磷(P)的净化效果及其对水华藻类生长的抑制能力,同时对处理后湖水的藻类生长潜力进行了测试.结果显示,刚毛藻在原始浓度总氮(TN)10.512 mg/L和总磷(TP)0.856 mg/L的富营养化湖水中能维持正常的生长代谢,并能有效去除水体中的N、P养分.在室内12 d培养期间,刚毛藻对TN、氨氮(NH4-N)、TP和无机磷(PO4-P)的平均去除率分别达53.13%,44.40%,35.71

东湖沿岸带底栖藻类群落的时空变化

武汉东湖是一个浅水富营养湖泊,其沿岸带底栖藻类群落的季节分布特征明显,夏季的优势种群是一些体积很小的硅藻类曲壳藻(Achnanthes spp.),其他大部分季节是绿藻门的团集刚毛藻(Cladophora glomerata)和硅藻门的变异直链藻(Melosira varians)。不同样点间的底栖藻类现存量差异不显著,但优势种类不同,以团集刚毛藻为优势的绿藻在处于中富营养区域的磨山样点比例最高,以变异直链藻为优势种的硅藻在严重富营养化的水果湖样点中比例最高。底栖藻类月平均现存量(以叶绿素a计)的时间变化

两种藻类对水体氮、磷去除效果

借助人工装置和露天水池,通过分析实验水体中氮、磷元素浓度的变化,研究了实验室条件下一种绿球藻(Chlorococcumsp.)和露天小型生态系统中寡枝刚毛藻(Cladophora oligoclonaKütz).对污水中氮磷营养的去除效果.结果显示:绿球藻在高浓度氮和磷的污水中生长良好并维持较高的氮磷去除率,在6天处理期间,人工污水中总溶解性氮、硝酸盐氮、氨氮、总溶解性磷的去除率分别达到46.2%,37.8%,98.4%和79.3%;在对天然湖泊水的处理中,绿球藻对总溶解性磷的去除率在第5天为79.2%.

Ecballocystopsis dichotomus sp. nov. (Chlorococcales, Chlorophyceae) from China

Ecballocystopsis dichotomus sp. nov. is the third described species of Ecballocystopsis that grows on rock under water and epiphytically on the filaments of Cladophora and Mougeotia (green algae) collected in a small irrigation ditch in Chong-yang county, Hubei Province (East longitude 29 degrees 30', North latitude 114 degrees 10') and in Zhu-xi county, Hubei Province (East longitude 32 degrees 20', North latitude 109 degrees 45'). The new species differs from E. indica IYENGAR (1933) in having dichotomous branching and its smaller sized thallus; it differs from the second species, E. desikacharyi PRASAD (1985), in having looped filaments, dichotomous branching and smaller cells. Three patterns of cell divisions were observed in E. dichotomus sp. nov. (transverse, longitudinal and oblique). It may be that the new species is evolutionary a more advanced species based upon the structure of its thallus and the manner of spore formation. The systematic position of the genus, based on the comparative studies of the genus Ecballocystis BOHLIN with Cylindrocapsopsis IYENGAR, is discussed.

藻体对水环境中N、P及重金属Cu2+、Pb2+、Cd2+、Cr6+的吸附特征研究

随着全球生态环境的恶化，各国日益重视对水体中各种污染物的治理。利用藻类的吸收、富集和降解作用，可以去除污水中的营养物质、重金属离子和有机污染物，与其他物理、化学及工程的方法相比，该技术具有以下优点：成本低、能耗小、治理效果较好，对环境污染小，有利于资源化，有利于整体生态环境的改善，是治理水质污染的新途径。 本文利用几种大型海藻对富营养化海水进行处理，结果发现孔石莼、刚毛藻均有很强的吸收N、P的能力，吸收能力依次为褶曲刚毛藻>束生刚毛藻>孔石莼。水体中褶曲刚毛藻3 g/L含量，在3～5小时之内，可把中等以上富营养化海水中的N、P降低至一类海水水平。利用刚毛藻处理富营养化地下海水和养殖废水，进行海参和大菱鲆养殖试验，探索藻类净化水质和废水循环利用的新模式，使水体保持较低的营养盐状态，减轻养殖废水对环境的影响，实现了海水养殖业与环境的可持续发展。 刚毛藻在我国近海滩涂分布广泛，利用它来处理富营养化水体，并和水产养殖业相结合，既净化水体，使养殖废水能循环利用，满足水产养殖的需求，又改善水产业生态环境。同时，将回收藻体生产优质饲料、食品和药物等，实现藻类资源的高值利用。刚毛藻营养丰富，用其替代鼠尾藻作海参饲料，资源丰富，成本低，效果好，是一种值得加以开发利用的宝贵资源，具有广泛的应用前景。 生物吸附法是一种经济有效的移除废水中有害重金属离子的方法。由于藻类细胞壁中的多聚糖可提供吸附重金属的位点，廉价而蕴藏丰富的海藻对多种重金属表现出很强的吸附能力。所以本文通过分批实验，研究了非活体刚毛藻对水体中重金属Cu2+、Pb2+和Cd2+的吸附影响因子、吸附热力学、吸附动力学及吸附机理，得到了平衡等温线及动力学数据。吸附过程的最佳pH值为5.0，吸附量随温度的升高而增加，水体中常见的Na+、K+、Ca2+、Mg2+阳离子及Cl-、NO3-、SO42-、C2O42-等阴离子的存在对吸附的影响并不显著。EDTA存在时，吸附百分率大大降低。吸附等温线符合Langmuir和Freundlich方程。刚毛藻对重金属Cu2+、Pb2+和Cd2+的吸附容量很高，25℃时，对Cu2+、Pb2+和Cd2+的最大吸附容量分别为1.61 mmol/g、0.96 mmol/g和0.98 mmol/g，且吸附过程为吸热反应。刚毛藻对重金属Cu2+、Pb2+和Cd2+的吸附过程为化学吸附，在吸附过程中藻体表面的官能团可能与金属离子发生了螯合作用。吸附动力学过程符合pseudo-二级动力学模型，在初始的30min内，吸附速率很快，随后速率逐渐降低。解吸试验表明，用EDTA可以对重金属进行回收，刚毛藻可以循环利用。实验结果表明刚毛藻是一种高效、经济实用的生物吸附材料，可用来吸附回收水体中的重金属Cu2+、Pb2+和Cd2+等。 通过非活体刚毛藻对重金属Cr6+的吸附影响因子、吸附动力学、吸附机理的研究发现，刚毛藻对Cr6+具有很强的还原能力，对电镀废水中的Cr6+的还原去除提供了非常好的方法。吸附过程的最佳pH值为2～3，实际电镀废水通常在此pH范围，因此处理实际废水时，首先在原酸性条件下，对Cr6+进行还原去除，然后调废水pH至5.0，继续进行吸附，去除其他二价离子及被还原的三价Cr离子，实现了利用同一材料还原Cr6+为Cr3+，并将Cr3+和其他重金属离子同时去除。通过对机理的讨论，认为刚毛藻对Cr6+的生物吸附过程不是一个简单的“离子交换过程”，而是一个“吸附还原过程”。在海藻量足够的前提下，只要时间足够长，Cr6+可被彻底还原去除。 利用工业废弃物褐藻渣，对水体中重金属离子Cu2+、Pb2+、Cd2+及Cr6+的生物吸附特性分别进行了讨论，结果表明褐藻渣对重金属离子的吸附特性与刚毛藻一致，吸附等温线符合Langmuir和Freundlich方程，在25℃时，pH为5.0时，由Langmuir方程求出褐藻渣对Cu2+、Pb2+和Cd2+的最大吸附容量分别为4.20 mmol/g、3.13 mmol/g和2.97 mmol/g。褐藻渣对低、高浓度的重金属Cr6+都具有很强的吸附能力，且移除效果比较彻底。实际应用结果表明，褐藻渣是一种高效、经济实用的生物吸附材料，可用来吸附回收水体中的重金属离子，具有广泛的应用前景。

Wydajność asymilacji azotu na przykładzie wybranych gatunków roślin wodnych

Organizmy autotroficzne żyjące w ekosystemach wodnych, czerpią azot nieorganiczny z azotanów, azotynów i amoniaku. Związki te dostają się do zbiorników wodnych wraz ze spływem powierzchniowym, opadami oraz wodami gruntowymi. Wszystkie formy związków azotu ulegają licznym przemianom biochemicznym zachodzącym w słupie wody. Mowa tu głównie o amonifikacji, nitryfikacji oraz denitryfikacji częściowej i całkowitej. Jako, że z tymi przemianami wiąże się także zmiana stopnia utlenienia, zajście powyższych reakcji w głównej mierze zależy od stężenia tlenu w wodzie (Lampert i Sommer 2001). Glony z rodzaju błonica (Ulva) i gałęzatka (Cladophora) większą część swojego cyklu życiowego spędzają blisko powierzchni wody, gdzie przeprowadzają fotosyntezę i intensywnie się namnażają. Wiąże się również z wysokim zapotrzebowaniem na biogeny oraz z silną konkurencją o inne zasoby (jak np. światło) z innymi roślinami wodnymi. Obok węgla, wodoru i tlenu glony i rośliny wodne wymagają do wzrostu i swojego rozwoju dodatkowych elementów (między innymi N, P i mikroelementy). Większość z tych składników jest zwykle obecna w ekosystemie wodnym w odpowiednich ilościach w stosunku do potrzeb organizmów fotosyntetyzujących i nie należy od czynników limitujących wzrost. Jednak zawartości nieorganicznych form azotu i fosforu mogą być na tyle niskie, że powodują limitację wzrostu makroglonów w wodach powierzchniowych. Asymilacja pierwiastków biogennych (N, P) z wody zachodzi dzięki specjalnym, energo-zależnym i powiązanych z błoną komórkową systemom permeazy, których funkcją jest zapewnienie podwyższonego, wewnątrzkomórkowego stężenia tych jonów jako substratów do dalszych szlaków i procesów enzymatycznych (Gumiński 1990).

Contributo para o estudo das macroalgas do intertidal da ilha da Madeira: diversidade, distribuição e sazonalidade

Ao longo de um ano (junho 2009 – maio 2010), estudou-se as comunidades de macroalgas do intertidal de quatro locais na costa sul (Reis Magos, Barreirinha,Cais do Carvão e Ribeira Brava) e quatro na costa norte (Porto da Cruz, Seixal,Praia da Laje e Porto Moniz) da ilha da Madeira. A área de estudo estendeu-se desde a linha de maré baixa até à zona superiordo intertidal. Identificou-se um total de 73 Taxa na ilha da Madeira: 1 Cyanobacteria, 35 Rhodophyta, 18 Ochrophyta e 18 Chlorophyta. No sul foram identificados 49 Taxa (17 exclusivos desta costa) e no norte 56 Taxa (24 exclusivos). Duas metodologias conjugadas permitem-nos caracterizar o coberto algal do Intertidal rochoso da ilha da Madeira: amostragem manual e trabalho em laboratório (trabalho mais detalhado e rigoroso) e análise de imagens digitais através de um programa informático específico (determinação de categorias ecológicas). Considerando as categorias ecológicas, o intertidal da ilha da Madeira é dominado por Musgo Calcário e Crosta não calcária. Duas espécies, Corallina elongata e Padina pavonica, são dominantes na ilha da Madeira e sete espécies são novos registos: Ganonema farinosum, Hypnea arbuscula, cf. Itonoa marginifera, Grateloupia dichotoma, Cystoseira wildpretii,Sargassum furcatum e Cladophora lehmanniana. As análises CLUSTER e nMDS determinaram a existência de semelhanças relativamente elevadas entre quatro locais de amostragem, no entanto verificou-se uma primeira diferenciação entre norte e sul. Existe uma desigualdade evidente do coberto algal entre as duas costas, com predominância de algas vermelhas e verdes no sul, contrastando com a maior ocorrência de algas castanhas no norte. Esta diferença poderá ser causada pela herbivoria (mais evidente a sul) e pelo hidrodinamismo (mais forte no norte). Verfificou-se que a exposição à ação das ondas é o principal fator responsável pela variação entre amostras (R=0,537, Sig.=0,1%).

Photosynthetic responses to temperature in tropical lotic macroalgae

A comparative analysis of the photosynthetic responses to temperature (10-30°C) was carried out under short-term laboratory conditions by chlorophyll fluorescence and oxygen (O2) evolution. Ten lotic macroalgal species from southeastern Brazil (20°11-20°48′S, 49°18-49°41′W) were tested, including Bacillariophyta, Chlorophyta, Cyanophyta, Rhodophyta and Xanthophyta. Temperature had significant effects on electron transport rate (ETR) only for three species (Terpsinoe musica, Bacillariophyta; Cladophora glomerata, Chlorophyta; and C. coeruleus, Rhodophyta), with highest values at 25-30°C, whereas the remaining species had no significant responses. It also had similar effects on non-photochemical quenching and ETR. Differences in net photosynthesis/dark respiration ratios at distinct temperatures were found, with an increasing trend of respiration with higher temperatures. This implies in a decreasing balance between net primary production and temperature, representing more critical conditions toward higher temperatures for most species. In contrast, high net photosynthesis and photosynthesis/dark respiration ratios at high and wide ranges of temperature were found in three species of green algae, suggesting that these algae can be important primary producers in lotic ecosystems, particularly in tropical regions. Optimal photosynthetic rates were observed under similar environmental temperatures for five species (two rhodophytes, two chlorophytes and one diatom) considering both techniques, suggesting acclimation to their respective ambient temperatures. C. coeruleus was the only species with peaks of ETR and O 2 evolution under similar field-measured temperatures. All species kept values of ETR and net photosynthesis close to the optimum under a broad range of temperatures. Increased non-photochemical quenching, as a measure of thermal dissipation of excess energy, toward higher temperatures was observed in some species, as well as positive correlation of non-photochemical quenching with ETR, and were interpreted as two mechanisms of adaptation of the photosynthetic apparatus to temperature changes. Different optimal temperatures were found for individual species by each technique, generally under lower temperatures by O2 evolution, indicating dependence on distinct factors: increases in temperature generally induced higher ETR due to increased enzymatic activity, whereas increments of enzymatic activity were compensated by increased respiration and photorespiration leading to decreases in net photosynthesis.

Taxonomia, distribuição ambiental e considerações biogeográficas de algas verdes macroscópicas em ambientes lóticos de unidades de conservação do sul do Brasil

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

The impact of coastal urbanization on the structure of phytobenthic communities in southern Brazil

The anthropogenic pressures on coastal areas represent important factors affecting local, regional, and even global patterns of distribution and abundance of benthic organisms. This report undertakes a comparative analysis of the community structure of rocky shore intertidal phytobenthos in both pristine like environments (PLE) and urbanized environments (UBE) in southern Brazil, characterizing variations on different spatial scales. Multivariate analysis of variance indicated that the PLE is characterized by a larger number of taxa and an increased occurrence of Rhodophyta species in relation to UBE. In contrast, UBE were dominated by opportunistic algae, such as Cladophora and Ulva spp. Significance tests further indicated higher species richness and Shannon-Wiener diversity on the PLE in relation to UBE. Here we provide data showing the magnitude of seaweed biodiversity loss and discuss direct and indirect consequences of unplanned urbanization on these communities. (C) 2012 Elsevier Ltd. All rights reserved.