Mutualism between euryhaline tilapia Sarotherodon melanotheron heudelotii and Chlorella sp.—Implications for nano-algal production in warmwater phytoplankton-based recirculating systems     

Sylvain Gilles  Grard Lacroix  Daniel Corbin  Ngansoumana B  Carla Ibaez Luna  Jacob Nandjui  Allassane Ouattara  Oussni Oudraogo  Xavier Lazzaro 《Aquacultural Engineering》2008,39(2-3):113-121

The West-African euryhaline tilapia, Sarotherodon melanotheron heudelotii shift from visually feeding on zooplankton when juveniles to mostly filter feeding on phytoplankton when adults. When reared using an appropriate ration in intensive aquaculture systems, S. m. heudelotii also consume algal-based detritus, and contribute to sediment mineralization, clean up their environment, and ultimately stimulate and sustain algal growth. We analysed such practical advantages for phytoplankton-based recirculating systems, using S. m. heudelotii and Chlorella sp. as biological material originating from the prototype of such a system operated in Senegal. We performed a 24-h factorial design experiment in 36 tubs, cross-classifying three levels of S. m. heudelotii (fishless control, unfed fish, and fed fish) with four levels of Chlorella initial density.Chlorella overall mean density increased significantly from fishless, to unfed fish, and fed fish treatments, and with Chlorella initial density. S. m. heudelotii did not alter nitrogen nor phosphorus concentrations, only affected by algal initial densities. Most ammonia excreted by fish was probably uptaken by Chlorella. Bacteria-mediated diurnal nitrification was possibly an alternative ammonium loss mechanism at highest oxygen concentrations. Algae were not limited by nitrogen or phosphorus but most likely by low dissolved organic carbon availability. Chlorella differential responses with fed vs. unfed Sarotherodon suggest that CO₂ supplied by heterotrophic S. m. heudelotii respiration played a key role. Observed Chlorella growth rates were similar to the highest rates obtained in algal mass cultures, enriched with CO₂, nitrate and phosphate, under artificial lighting.Our results suggest the existence of a Sarotherodon-Chlorella mutualism in our systems, where S. m. heudelotii provide CO₂, the major limiting factor of Chlorella growth, whereas Chlorella oxygenate and detoxify the water media from ammonia, promoting S. m. heudelotii production. This mutualism could be used to optimize photosynthetic suspended-growth aquaculture systems, particularly in the Tropics where light is abundant and temperature is continuously high.  相似文献   

高,宝,邵伯湖浮游植物资源调查报告     

张彤晴 《水产养殖》1993,(6):12-14

本文报道了高，宝，邵伯湖游植物资源调查结果。  相似文献   

长江口外水域浮游植物垂直分布研究   总被引：5，自引：0，他引：5  

顾新根  袁骐  杨蕉文  华棣 《中国水产科学》1995,2(1):28-38

本文是１９８８年丰水期（８月）、枯水期（１２月）和１９８９年丰水期（８月）长江口外水域浮游植物垂直分布研究的实初步结果。由于研究海区存在着多种水第的水平和垂直分布的混合导致浮游植物的垂直分布现象相当复杂。丰水期水体的垂直结构状况是决定浮游植物垂直分布的最重要因素。  相似文献   

河蟹开口饵料———单胞藻的定向培育试验          下载免费PDF全文

王海雷  赵文  李晓东  刘胥  何志辉 《水产科技情报》2004,31(4):150-153

试验在沿海混盐水池塘中施入不同品种和不同比例的肥料(有机肥和无机肥)，研究施肥对浮游植物种群增长的影响，并分析了在混盐水池塘中影响施肥效果的几种可能因素。试验结果表明：在混盐水中施肥可以达到定向培育浮游植物的目的，浮游植物的生物量在施肥后4～5d进入指数增长期，7～8d达到高峰期。单施氮肥和施氮磷混合肥对生物量并没有太大影响，最高生物量可达280mg／L以上，同时种类趋于单一化，完全可以满足河蟹育苗生产中河蟹幼体对开口饵料的需要。  相似文献   

黄海春季浮游植物的调查研究   总被引：12，自引：0，他引：12  

王俊 《海洋水产研究》2001,22(1):56-61

1998年 5月 16日～ 6月 1日 ,对黄海 ( 33°0 0′～ 39°30′N,12 1°0 0′～ 12 5°30′E)进行了浮游植物调查研究 ,结果显示 :1998年春季黄海已鉴定的浮游植物有 14属 2 9种。其中 ,硅藻门有 10属 2 1种 ,甲藻门 4属 8种。在硅藻门中圆筛藻属的种类最多 ,有 7种 ,其次是根管藻属 ,有 3种。甲藻门中甲藻属的种类最多 ,有 5种。浮游植物的平均数量为 2 .2 3× 10 4 个 / m3,其中 ,硅藻门的平均数量为1.55× 10 4 个 / m3,占浮游植物总量的 69.5% ,甲藻门的平均数量为 0 .68× 10 4 个 / m3,占浮游植物总量的 30 .5%。黄海北部浮游植物的数量高于黄海中、南部。黄海浮游植物分布密集区主要在调查区西、北部。与 1986年同期黄海浮游植物调查资料相比 ,1998年春季黄海浮游植物的种类组成和 1986年春季相似 ,但浮游植物的数量减少 64.6%。  相似文献   

Outdoor phytoplankton continuous culture in a marine fish–phytoplankton–bivalve integrated system: combined effects of dilution rate and ambient conditions on growth rate, biomass and nutrient cycling     

Sbastien Lefebvre  Ian Probert  Christel Lefranois  Jrme Hussenot 《Aquaculture (Amsterdam, Netherlands)》2004,240(1-4):211-231

Natural phytoplankton populations were cultured in outdoor continuous cultures using fish-farm effluents as the source of nutrients. The dilution rate was assumed to be the integrating factor of phytoplankton growth and biomass development (flux and stock). In this context, the combined effects of (i) dilution rates of the outdoor culture and (ii) ambient conditions were tested on phytoplankton growth, biomass and cycling of the major nutrient elements (C, N and P). Experiments were carried out in outdoor polyester tanks (0.7 m deep), homogenised by gentle aeration. Si/P ratio was balanced at around 5 in the inflow in order to induce diatom domination while maintaining high N and P assimilation by phytoplankton. Nutrient cycling was assessed through analyses of the different forms of particulate and dissolved nutrients in the inflow and the outflow. Culture dilution rates determined the longevity of the culture and the assimilation efficiency of nutrients. Dissolved phosphorus was the most limiting nutrient. The optimal dilution rate was approximately 0.5 day⁻¹ at 10 °C and 1.5 day⁻¹ at 20 °C with a mean diatom biomass of 9 μM P. Under these conditions, 80% of the dissolved nutrients provided to the tanks were transformed, a production of 8 g C m⁻² day⁻¹ and an assimilation rate of 0.3 g P m⁻² day⁻¹ were recorded. Assimilation by diatoms was the major pathway of nutrient cycling. During the experiment, a bottom sediment developed progressively and this also played an important role in denitrifying the excess dissolved nitrogen in the fish-farm effluent. However, the results showed that diatom biomass can collapse and we hypothesize that this was the consequence of an increase in cellular sinking rates due to cell aggregation under nutrient or light stress. Modelling approaches are needed in future research in order to determine optimal dilution rates taking into account phytoplankton growth rates, nutrient inputs and ambient conditions (e.g. light and temperature).  相似文献   

长江云阳江段四大家鱼产卵场浮游植物初步调查   总被引：3，自引：0，他引：3  

唐毅  刘建虎  唐洪玉  李涛  刘绍平  陈大庆 《淡水渔业》2003,33(3):32-35

四大家鱼繁殖期间 ( 2 0 0 2年 5月至 6月 )对云阳江段产卵场浮游植物进行了调查 ,结果表明 :浮游植物生物量为 0 .5 0 6 75mg L ,其中硅藻为优势种群。其浮游植物种类组成和数量与江河汛期水文状况有明显关系。  相似文献   

Effect of organic fertilizer on plankton primary productivity in fish ponds   总被引：2，自引：0，他引：2  

Doychin Terziyski  George Grozev  Roumen Kalchev  Angelina Stoeva 《Aquaculture International》2007,15(3-4):181-190

The effect of cattle organic fertilizer on plankton primary production and related variables was tested in six Bulgarian fish ponds situated close to the town of Plovdiv in Bulgaria. At the beginning of the experiment (16th of May 2004, about 10 days after filling with water) a suppression of plankton metabolism was observed and after that the ponds treated with manure demonstrated significantly higher productivity than the controls, especially during the transition to the autumn season when the water column was more regularly mixed. The other measured variables (Secchi disk readings, plankton chlorophyll-a and respiration, assimilation number per unit chlorophyll-a) did not show significant differences between the treated and control ponds.  相似文献   

大力加湖鲟鱼放养场浮游植物及鱼产潜力     

宋鑫  姜作发  唐富江  刘立志 《水产学杂志》2006,19(1):68-71,76

2004年5、7、9、12月对大力加湖浮游植物的种类组成结构特征进行了研究。结果表明：大力加湖鲟鱼放养场浮游植物96个种属,密度255.54×10~4 ind．/L,生物量14.166 mg/L。浮游植物季节变化比较明显,密度秋季最高为456.160×10~4 ind．/L,生物量以秋季最高30.105 mg/L。多样性指数变化是夏季＞秋季＞冬季＞春季；均匀度指数变化是冬季＞夏季＞秋季＞春季。全库总鱼产潜力527760 kg,总放养量2804800尾。  相似文献   

东风西沙水源地浮游植物种类组成与数量分布特征     

姚磊 《安徽农业科学》2014,(16):5186-5188,5285

分析了东风西沙水源地浮游植物种类组成、优势种分布、群落结构分布以及多样性等特征.结果表明,东风西沙水源地共监测出藻类6门共64种（属）,分别为蓝藻、绿藻、硅藻、隐藻、裸藻、金藻,其中硅藻和绿藻共47种,为水源地的主要浮游植物种类;浮游植物优势种单一,主要为硅藻门的短小舟形、克洛脆杆藻,隐藻门的尖尾蓝隐藻,以及蓝藻门的铜绿微囊藻,且优势度值较小;监测期间浮游植物密度为8.20×10^5 ～8.40×10^6 cells/L,均值为3.71×10^6 cells/L;群落特征指数统计结果表明东风西沙目前水质较好,总体上处于轻或无污染状态.  相似文献