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531.
532.
The dynamic model of physical-biological engineering for purifying water quality in Lake Taihu needs the parameter of sedimentation rate (SR). Especially, it is seldom reported how SR is influenced by interactions between algae and aquatic plant. So 6 enclosures with each area of 5×5 m2 were constructed in Wulihu with 2 m depth, a small hypereutrophic bay of Taihu Lake, China. Enclosures, in which the original water quality was the same as that in surrounding lake, were input Eichhomia crassipes at various original densities from 0-6 kg·m-2 on August 9, 1996. SR had been measured separately at depths of 0.6, 1.2f 1.8 m in each enclosure during 20 days. Main results were as follows:1) SR average in enclosures (17.3g·m-2 d-1) was as much as about 1/14 that in the surrounding lake; 2) The deeper was it, the higher rate was it in each enclosure, generally; 3) SR cures versus original densities of Eichhomia crassipes (ODE) in enclosures had the ship of "V" at different depths; SR minimuma were observed in the enclosure with original meso-density of Eichhomia crassipes (EMESO, 4kg·m-2), the average of SR minimuma was about 8.55 g ·m-2 d-1) SR in enclosures with original hypo-density (EHYPO, 0-3kg·m-2) were mainly negative related with water temperature and light intensity;while those with original hyperdensity (EHYPR, 5-6kg·m-2) were mainly negative related with transparency (SD) instead.These SR-distribution characteristics may be explained by interactions between dead algae and relics of Eichhomia crassipes. 相似文献
533.
NFMG法培养发菜的研究 总被引:4,自引:0,他引:4
采用NFMG法获得发菜藻种,经人工控制条件下的培养,成功地培养出肉眼可见的发菜藻体,表明人工培养发菜初获成功。 相似文献
534.
1992年11月 ̄1993年10月,在安徽太平湖水库,同时用藻类生长潜力测试法(AGP试验)和外源添加营养的黑白瓶测定初级生产力法,对陵山站的水体分季度进行了分析测试。其结果表明,这两种方法对太平湖水库的营养评价均是行之有效的,而且二者的结果也能相互比较、相互验证;太平湖水库的不同季节,其主要营养限制性因子也各异。在枯水期,磷是藻类种群和密度的第一限制性营养元素;丰水期,由于各营养元素都相对缺乏, 相似文献
535.
武汉东湖底栖藻类在不同基质上生长的比较 总被引:4,自引:2,他引:2
测定了富营养化武汉东湖中的底栖藻类在不同人工基质上建群发展为成熟群落的生物量(Chl.a),定性分析了人工和天然基质上成熟硅藻群落的种类组成和结构特征.通过比较建群期间底栖藻类在花岗岩、玻璃、塑料(PVC)和木板4种不同人工基质上的生物量变化,发现底栖藻类在PVC上的生物量峰值(Chl.a,71.0μg/cm2)明显高于其它人工基质,说明PVC是最适合底柄藻类生长的人工基质.分析发现人工基质花岗岩上底柄硅藻群落的种类组成、主要优势种类、群落的相似性指数、多样性指数都和天然基质上的硅藻群落是高度相似的,显示该人工基质能够代表天然基质上的藻类群落,表明花岗岩应该是以底栖藻类作指示生物监测和评价水质的理想人工基质. 相似文献
536.
537.
于1981年3月在西沙群岛永兴岛采集原绿藻标本。用光镜和电镜对所采原绿藻进行研究。结果表明,原绿藻为简单的原核、单细胞藻类,在同一生境的相同宿主体表有4种不同的细胞构造类型:第1种类型,中央大“液泡”,类囊体单条、平行分散于周围区的细胞质中;第2种类型,中央是大“液泡”,周围区内类囊体多,并形成垛叠;第3种类型,许多小泡充满细胞的大部分,类囊体穿插于小泡之间;第4种类型,有中央大“液泡”,还有许多小泡分散在细胞周围区。上述分类以类囊体和“液泡”的结构和分布为主要分类依据,反映出不同结构的进化意义。表明中国西沙群岛有丰富的原绿藻资源。 相似文献
538.
南麂列岛自然保护区药用海藻资源及其应用 总被引:1,自引:0,他引:1
本文报道了南麂列岛国家海洋自然保护区药用海藻的种类组成及其应用。经初步鉴定南麂列岛共有海藻类400余种,其中已知具有药用功效的海藻111种(小于20μm的微型藻类为16种,20~200μm的小型藻类为9种,大于200μm的大型海藻类为86种),隶属于红藻门49种、褐藻门20种、硅藻门15种、绿藻门14种、蓝藻门8种和甲藻门5种。根据藻类的药理、生理特性及药用功效,可划分为9类:(1)抗菌药(AF);(2)抗凝血、止血药(AB);(3)抗病毒药(AD);(4)抗高血压药(AH);(5)清热解毒药(APT);(6)驱虫药(AI);(7)抗肿瘤药(AT);(8)抗心脑血管药(BC);(9)抗艾滋病药(AIDS)。 相似文献
539.
540.
P. Czar 《Geological Journal》2005,40(4):405-424
Calcareous microflora occur commonly in the early Serpukhovian (late Mississippian) rocks from the Guadiato Area (southwestern Spain) despite the fact that this area contains mostly siliciclastic sediments. The microflora recorded in the carbonate beds is regarded as representative of both relatively deep‐water and shallow‐water facies and can be compared with the slope and shelf facies environments distinguished in the Guadiato Area. Up to 45 algal taxa have been identified in the carbonate beds, of which 26 taxa occur in the relatively deep‐water assemblages, whereas the shallow‐water assemblages are composed of up to 43 taxa. The entire algal assemblage is dominated by calcifoliids, common cyanobacteria and incertae sedis, but the shallow‐water assemblages contain more commonly dasyclads, red algae and aoujgaliids. Most of these taxa are present, but poorly known, in other Serpukhovian carbonate platforms in the western Palaeotethys. Some algae (Hortonella uttingii, Kamaenella tenuis and Koninckopora inflata), usually regarded as being restricted to the Viséan, have been found in Serpukhovian rocks in the Guadiato Area, and also in Algeria, thus their stratigraphic ranges might be extended up to the Serpukhovian. Other important taxa include: Archaeolithophyllum, Cabrieropora, Calcifolium, Falsocalcifolium, Fourstonella, Frustulata, Kulikia, Neoprincipia and ‘Windsoporella’, which are exceptionally recorded in Serpukhovian rocks, or not recorded at all, because they are typically recorded in the Pennsylvanian (cf. Clavaporella), although some of them show earlier occurrences in Viséan rocks (Claracrusta, Paraepimastopora and Sparaphralysia). Some of the algal taxa can be considered as potential regional markers for the Serpukhovian, such as Archaeolithophyllum, cf. Clavaporella, Frustulata and Girvanella (?) sp. The algal assemblages found in the Guadiato Area show the greatest similarities with those in the Béchar‐Mézarif (Algeria), Pyrenees and Montagne Noire (southern France). Copyright © 2005 John Wiley & Sons, Ltd. 相似文献