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稳定高效的多营养层级景观生态系统构建是近年来水族行业的发展热门,为探究海水水族箱在引入大型海藻后微宇宙生态系统结构和稳定性的变化,分别对不同处理组进行水质指标、浮游生物及细菌群落结构分析。结果表明：（1）有藻组水体溶解氧（DO）含量和pH上升趋势高于无藻组,并可维持亚硝态氮（NO2--N）含量在较低水平,实验结束时磷酸盐（PO43--P）及铵态氮（NH4+-N）含量显著低于无藻组（P < 0.05）。（2）有藻组细菌多样性及均匀度指数显著低于无藻组（P < 0.05）;浮游生物群落均匀度指数存在显著组间差异（P < 0.05）。（3）细菌群落结构分析结果显示,无藻及有藻组第一、二优势菌门均为变形菌门（Proteobacteria）、放线菌门（Actinobacteria）,无生物对照组分别为变形菌门和厚壁菌门（Firmicutes）;各处理组浮游生物群落的第一优势门均为硅藻门（Bacillariophyta）,至少占样品中浮游生物群落丰度的40%以上,第一优势属均为直链藻属（Melosira）。（4）CCA结果显示,无藻组微生物优势种丰度与营养盐含量呈正相关关系,与溶解氧（DO）及pH负相关,有藻组则相反。通过以上结果可推测,不同营养层级的微宇宙系统浮游生物及细菌群落组成不同,培养针叶蕨藻（Caulerpa sertularioides）能有效改善生态水族箱水质环境并影响水体微宇宙结构,有利于构建稳定高效并美观的海水景观生态系统。 相似文献
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不同浓度Ca~(2+)对三角帆蚌养殖水体微生物和浮游生物的影响 总被引：1，自引：0，他引：1
研究了不同Ca2+浓度条件下,三角帆蚌养殖水体中的细菌总量、致病性肠道菌和葡萄球菌及藻类的增长情况。研究结果表明:实验水体的细菌总量增长呈现出比较完整的逻辑斯谛增长特性,Ca2+对细菌总量的增长起着调控作用,Ca2+浓度越高,对于细菌的生长抑制就越明显。对于致病性肠道菌,10mg/L组Ca2+浓度有利于增长,20mg/L和30mg/L组在后期具有明显的抑制增长的作用。葡萄球菌在20mg/L的Ca2+浓度下增长最快,30mg/L组则明显抑制葡萄球菌的生长。在10￣30mg/L的Ca2+浓度范围内,水体中藻类的增长不受Ca2+浓度控制。 相似文献
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[目的]探讨影响3个池塘形成不同藻类水华的生态学原因。[方法]2007年7～10月对河南省延津县3个形成不同藻类水华的养殖池塘进行逐月定点水生生物学和水化学调查与检测。[结果]1号塘为绿藻水华,优势种为衣藻、小球藻;2号塘为裸藻水华,优势种为裸藻（Euglena）;3号塘为微囊藻水华,优势种铜绿微囊藻。绿藻水华的发生与低含量的总磷（约0.86mg/L）和高的氮磷比（约13.1）有密切关系,裸藻水华的发生与高的总磷含量（约2.08mg/L）和低的氮磷比（约7.3）有显著关系,而微囊藻水华发生与较高的总磷含量（约1.30mg/L）和较高的氮磷比（约9.2）有密切关系。[结论]池塘藻类水华的控制应以预防为主,重点是调节控制好水质。 相似文献
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精养鱼池浮游生物及其鱼产力分析 总被引：1，自引：0，他引：1
[目的]分析精养鱼池塘水体中浮游生物种群结构的变化规律,促进池塘高产技术的推广。[方法]对喀什地区渔业检测中心精养鱼池塘浮游生物的种类组成、现存量及其对鱼产量影响进行调查和分析。[结果]共检出浮游植物20属,隶属5门,总生物量为80.57mg/L,优势种群为蓝藻门和绿藻门。检出浮游动物8属,隶属4门,平均生物量2.19mg/L,优势种群为萼花臂尾轮虫和壶状臂尾轮虫。该池塘浮游生物总量为82.76mg/L;总鱼产力为1603kg/hm2。[结论]池塘水体浮游植物组成不尽合理,要防止蓝藻大量生长,减少对鱼类生长的不利影响,并适当增加鳙鱼的比例,以合理利用浮游生物资源。 相似文献
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Plankton indices explain interannual variability in Prince William Sound herring first year growth 
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下载免费PDF全文 This study examines the relationships between first year growth of juvenile Prince William Sound herring, temperature and their food. We present time series of herring first year growth, determined from scale measurements as a proxy for herring length, water temperature and indices of multiple trophic levels of plankton obtained from Continuous Plankton Recorder (CPR) sampling on the adjacent Gulf of Alaska shelf. We show that there was a significant correlation between herring growth and water temperature, when the three warmest years were excluded (the mean July and August temperatures were greater than 12.5°C in 1989, 2004 and 2005). There were also strong, significant relationships between the abundance of appropriately sized (for first‐feeding herring) planktonic prey groups and herring growth. First year herring growth was greater in years with higher abundances of diatoms, microzooplankton and small mesozooplankton but not related to variability in abundance of larger mesozooplankton (such as euphausiids and large copepods). Furthermore, the strong interannual relationship between diatoms and herring growth held true even in the warmest years where the relationship between temperature and growth broke down. We also found seasonal timing and abundance changes in the plankton in warm years that would make the prey more abundant during the summer months immediately after metamorphosis of the herring larvae. We thus conclude that young‐of‐the‐year herring may grow better in warm years because the timing of key prey is a better match for their first feeding. 相似文献
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Two strains (derepressed-nitrogen fixing, Mac-27 and phosphate solubilizing, PS-21) of Azotobacter chroococcum were inoculated in fish culture ponds, singly and in combination with inorganic fertilizers (urea, single superphosphate–SSP). Physico-chemical parameters of pond waters, plankton production and fish biomass were studied. Inoculation of A. chroococcum (Mac-27) enhanced nitrogenase activity and rate of nitrogen fixation. A slight reduction in nitrogen fixation and nitrogenase activity was noticed when urea at 96 kg ha–1 y–1 was mixed with the biofertilizer (Mac-27). Inoculation of PS-21 enhanced phosphate solubilization, but Kjeldahl-nitrogen concentration values remained low in comparison with controls. On the other hand, inoculation of Azotobacter (either strain) enhanced the accumulation of ammonium-N, nitrite-N and nitrate-N. A significant (p < 0.05) reduction in dissolved oxygen (DO) concentration also took place when Azotobacter (both Mac-27 and PS-21) was inoculated in fish ponds. However, when used along with inorganic fertilizers, the reduction was not significant. The pH values were only slightly lowered when the phosphate-solubilizing strain (PS-21) of Azotobacter was inoculated. Inoculation of biofertilizer enhanced plankton production, net primary productivity and fish biomass. However, highest values in most of these parameters were noticed only in ponds that were treated with the higher doses of inorganic fertilizers (urea 192 kg and SSP 1500 kg ha–1 y–1). © Rapid Science Ltd. 1998 相似文献