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1.
栉孔扇贝与海胆和海参混养的净化水质作用 总被引：4，自引：0，他引：4
在容水40 L、放养5个海参、混养10、20或30个海胆的水槽中分别加入0、1、2、4或6个壳长(6.65±0.30)cm的栉孔扇贝,研究了扇贝密度对净化海胆和海参混养池水质的作用。结果表明:扇贝密度极显著影响水体的叶绿素、氨氮、颗粒有机物(POM)和悬浮颗粒含量(P<0.01);显著影响水体的总颗粒物(TPM)含量(P<0.05)。每升水放养0.05个扇贝的水槽(即2个/水槽)中叶绿素的含量[(0.282±0.060)μg.L-1]显著高于其他各组(P<0.05),POM[(3.68±0.61)mg.L-1]和TPM[(13.47±0.92)mg.L-1]含量显著低于其他组(P<0.05)。扇贝放养后第2-3 d氨氮、POM、TPM和悬浮颗粒的含量显著增加,第3 d后保持相对平稳。 相似文献
2.
根据2015年秋季(10月)和2016年冬季(1月)、春季(4月)、夏季(7月)4个航次的调查研究,分析了獐子岛养殖海域表、底层水体中总悬浮颗粒物(TPM)、颗粒有机物(POM)和颗粒有机物比例(PCOM,%)的时空分布特征,结合POM与叶绿素a(Chl-a)及环境因子的相关性分析,探讨了悬浮颗粒物的影响因素及其与虾夷扇贝(Patinopecten yessoensis)底播养殖之间的潜在联系。结果显示,獐子岛海域TPM和POM的浓度变化范围分别为16.76~97.54、2.20~17.20 mg/L,年平均浓度分别为(31.65±9.58)、(6.97±2.08)mg/L。PCOM值的变化范围为8.69%~37.09%,平均值为(22.25±4.18)%。TPM浓度的季节变化趋势为秋季春季夏季冬季,最大值出现在秋季表层。而POM和PCOM的最高值出现在夏季,冬季的值最低。POM与TPM的平面分布趋势相似,大部分海域的平面分布比较均匀;春、夏季POM的分布呈现中部略高、四周略低的特点,秋、冬季与之相反;夏季底层显著高于表层(P0.01),其他季节表、底层无显著差异(P0.05)。4个季节中,獐子岛海域的POM与Chl-a的含量呈极显著正相关关系(P0.01);其中,春季底层和夏季表层的POM与Chl-a均存在极显著正相关关系(P0.01)。另外,只有夏季表层POM与盐度之间存在显著负相关关系(P0.05),说明夏季陆源输入对该海域的悬浮颗粒有机物有显著影响。 相似文献
3.
比较了刺参-中国对虾混养和刺参单养两种养殖模式下养殖池塘中底泥表层沉积物和水体悬浮颗粒物以及养殖刺参体组织中Mn、Cr、Hg、Zn、Cu、Pb、Cd、As等重金属的含量,并调查分析了两种养殖池塘水体中总悬浮颗粒物和颗粒有机物的变化,研究刺参-中国对虾混养模式对刺参生长环境及刺参体内重金属含量的影响。研究结果表明,刺参体组织中重金属Cu、As和Mn的含量在单养池塘和混养池塘变化趋势一致,且刺参体内Cu和As在混养池塘的含量要低于单养池塘。相比于单养模式,养殖池塘内悬浮颗粒物(TPM)和悬浮颗粒有机物(POM)的含量在混养模式下显著减少,这一结果表明刺参-中国对虾混养模式可显著改善刺参养殖水体的水环境状况。此外,在两种养殖模式下,悬浮颗粒物中不同重金属元素的含量均不相同且呈现出不同的变化趋势,悬浮颗粒物内Cr、Mn、Hg的含量在刺参-中国对虾混养模式下呈显著下降趋势,且含量低于单养池塘。表层沉积物中有机质含量具有一定的波动性,表现出先下降后升高的趋势,且混养池塘有机质含量比同期的单养池塘更高。表层沉积物的重金属含量与强热失量(LOI)的相关性分析结果表明,两种混养模式下,表层沉积物的Cd、Zn、Pb、Mn等重金属水平均与LOI呈正相关关系。 相似文献
4.
于2015年8—12月对混养奥尼罗非鱼的凡纳滨对虾池塘进行对虾体表固着类纤毛虫的研究。在显微镜10×10倍视野下纤毛虫个体数量处于1级(≥30个)情况下,试验池1~#、2~#和3~#池分别放养奥尼罗非鱼苗体长10.0 cm密度4 500尾/hm~2、体长2.1 cm密度15 000尾/hm~2、体长6.0 cm密度9 000尾/hm~2均可以使凡纳滨对虾体表的固着类纤毛虫个体数量降低到4级(≤3个),通过控制饲料的投喂量和投喂频率,每15天测定试验池对虾体表虫体个数,均处于4级(≤3个)水平,1~#、2~#和3~#池净利润分别为75 489、46 625、55 682元/hm~2。试验结果表明:混养一定数量的奥尼罗非鱼对凡纳滨对虾固着类纤毛虫疾病具有防治作用,为该类寄生虫导致的疾病防治提供参考。 相似文献
5.
《中国渔业质量与标准》2015,(3)
采用18个36 m2的围隔进行对虾单养和对虾–罗非鱼混养实验,利用N、S、P综合相对污染指数对单养和混养围隔底质有机负荷进行研究。实验分为6组,每组3个围隔。各围隔放养体长为(0.45±0.01)cm的凡纳滨对虾3 000尾,放养体重为(201±25)g的罗非鱼分别为0(Ⅵ组)、4(Ⅰ组)、8(Ⅱ组)、12(Ⅲ组)、18(Ⅳ组)和24尾(Ⅴ组),放养对虾1个月后再放养罗非鱼。实验期间各围隔均不进行水交换,实验周期为70 d。结果表明,各围隔底质中N、P、S呈现显著上升趋势,但对虾-罗非鱼混养围隔底质中N、P、S的积累量均小于对虾单养围隔。其中,Ⅲ组的N、P、S增长率最小。各组围隔相对污染指数排列如下:Ⅵ(10.78)Ⅴ(8.30)Ⅰ(7.68)Ⅳ(7.40)Ⅱ(6.09)Ⅲ(4.12),其中Ⅲ组的相对污染指数显著小于Ⅵ组(P0.05)。Ⅲ组为本实验的效果最佳组,即混养最佳配比为凡纳滨对虾8.3×105尾/hm2、罗非鱼3 320尾/hm2,罗非鱼均重为(201±25)g/尾。本研究可为对虾–罗非鱼混养中选定合适的养殖容量提供参考。 相似文献
6.
在原来单养罗非鱼池塘基础上,进行了主养罗非鱼混养草鱼模式试验,并与单养罗非池塘效果进行了对比分析。罗非鱼统一放养密度、草鱼三个不同的放养密度,罗非鱼产量没有显著差异,而草鱼的放养密度越大,池塘总产量越高,池塘水质较活,罗非鱼和草鱼生长情况均良好。单养池塘和混养不同密度草鱼池塘的罗非鱼出池规格无显著差异。混养草鱼池塘的罗非鱼平均成活率99.3%,放养相同批次和规格情况下,混养了草鱼池塘的罗非鱼比单养罗非鱼池塘成活率提高0.7个百分点,平均利润增加547.5元/667m2,显著提高了池塘经济效益。 相似文献
7.
8.
为研究敌百虫对奥尼罗非鱼幼鱼的急性毒性效应,采用96 h半静水式生物毒性试验方法,在水温(23.5±2.0)℃,溶解氧>5 mg/L的条件下,分别检测在曝气自来水(pH为6.5)和池塘水(pH为8.5)中敌百虫对奥尼罗非鱼幼鱼的急性毒性效应。结果显示:在曝气自来水中,敌百虫对奥尼罗非鱼幼鱼24、48、72、96 h的半致死质量浓度分别为3.68、3.31、2.05、1.57 mg/L,安全质量浓度为0.157 mg/L;在池塘水中,敌百虫对奥尼罗非鱼幼鱼24、48、72、96 h的半致死质量浓度分别为0.35、0.29、0.17、0.13 mg/L,安全质量浓度为0.013 mg/L。试验结果表明,在池塘水中敌百虫对奥尼罗非鱼幼鱼的毒性比在曝气自来水条件下强。 相似文献
9.
罗非鱼池塘循环水槽养殖初探 总被引：1，自引：0，他引：1
为探究罗非鱼在池塘循环水槽养殖模式下的养殖效果,于2017年开展池塘循环水槽养殖试验。3条水槽分别投放吉富罗非鱼鱼种19 950尾、34 713尾和40 166尾,规格为(3.5±0.11)g;水槽外池塘投放鳙鱼鱼种700尾、罗氏沼虾苗13.3万尾;试验中对养殖系统的水质指标和养殖产量进行分析测定。结果显示:养殖期间水温25.4~32.6℃,溶氧4.41~7.22 mg/L,p H 7.33~7.94,氨氮质量浓度0.11~2.07 mg/L,亚硝酸盐氮质量浓度0.004~0.107 mg/L,水质指标符合罗非鱼的生长要求;试验共持续165 d,3条水槽产量分别为4 481 kg、8 796 kg和10 632 kg,饲料系数分别为1.19、0.95和0.88,平均产量72.5 kg/m~2,水槽外池塘收获罗氏沼虾850 kg和鳙鱼1 300 kg;每公顷产值189 955.7元、利润40 454.7元,投入产出比为1∶1.25。研究表明,利用池塘循环水槽养殖罗非鱼在改善养殖环境、提高养殖产量和增加养殖效益方面优于传统养殖模式。 相似文献
10.
以河蟹单品种养殖池塘为对照,通过河蟹、青虾和塘鳢混养模式,检测养殖水体水温(WT)、pH值、透明度(SD)、溶解氧(DO)、总氮(TN)、总磷(TP)、化学需氧量(CODMn)和氨氮(NH4+-N)的变化,比较单养各混养模式的水体动态变化及产出效果。结果表明:混养池水温(WT)变化范围为19.1~31.5℃,pH值6.8~7.7,SD 35.0~60.0 cm,DO 5.1~7.6 mg/L,TN 1.53~1.79mg/L,TP 0.135~0.235 mg/L,CODMn7.86~8.59 mg/L,NH4+-N 0.35~0.48 mg/L,符合渔业水质标准(GB11607-89)和国家三类水指标(GB3838-2002)。方差分析结果显示,除水温和pH值外,混养模式与单养模式水质差异性显著。混养池平均纯收益为89 735元/hm2和91 860元/hm2,单养池平均纯收益为65 250元/hm2。混养比单养池多26 610元/hm2。 相似文献
11.
Accumulation, organic carbon and dry matter concentration of sediment in commercial channel catfish ponds 总被引：2，自引：0，他引：2
James A. Steeby John A. Hargreaves Craig S. Tucker Sue Kingsbury 《Aquacultural Engineering》2004,30(3-4):115-126
Sediment depth and organic carbon (OC) concentration were measured in sediment cores (n=675) collected from 45 commercial channel catfish ponds in northwest Mississippi from April to September in 1998 and 1999. Ponds had been in continuous catfish production from 14 days to 21 years. Sediment depth ranged from 1 to 95 cm and was heterogeneously distributed within ponds: least in the shallow end (26.3 cm) and greatest in deeper areas (33.7 cm). Mean sediment depth increased with pond age, although the rate of sediment accumulation was greatest in the first year (12.5 cm per year). Organic carbon concentration varied slightly within ponds ranging from 0.76 to 3.43% of dry matter (DM). Mean organic carbon concentration in the upper 2 cm of sediment (1.77%) was significantly greater than in the deeper sediment layer (1.55%). Mean dry matter content in the upper 2 cm of sediment averaged 24.2% of total wet weight. Mean dry matter for the lower sediment fraction was 37.8% of total wet weight. Despite large inputs of organic matter from feed and primary production, sediment organic carbon concentrations did not increase with pond age. 相似文献
12.
为比较越冬期循环水系统(RAS)与生物絮团系统(BFT)两种模式下大规格罗非鱼(Oreochromis niloticus)鱼种的生长性能与养殖水质的差异。选择RAS组与BFT组,进行为期67 d的养殖,测定养殖过程中罗非鱼种的生长情况以及水质的变化情况。结果显示,RAS组与BFT组增重率和特定增长率分别为(870.69±33.25)%、(3.39±0.05)%/d和(659.47±62.84)%、(3.02±0.13)%/d,RAS组显著高于BFT组;在水质控制方面,RAS组氨氮和亚硝酸盐从养殖初期到实验结束均维持在较低水平,而BFT组在初期氨氮和亚硝酸盐有升高的趋势,峰值分别达到了(4.53±0.72)mg/L和(6.68±1.8)mg/L,分别在第3天和第6天下降到较低水平,硝酸盐两组均呈现不断积累的趋势。结果表明,RAS系统养殖罗非鱼生长速度要高于BFT系统,RAS系统在水质控制方面略优于BFT系统。 相似文献
13.
David B. Rouse G. O. El Naggar M. A. Mulla 《Journal of the World Aquaculture Society》1987,18(2):57-60
Studies were conducted to determine the effect of stocking size and density of prawns in polyculture.
In one experiment, postlarval prawns (av. wt. 0.02 g) were stocked in six 0.02 ha earthen ponds at 35,00O/ha. Two ponds were stocked with tilapia fry (av. wt. 0.14 g) and two were stocked with tilapia fingerlings (av. wt. 30.1 g), each at 10,000/ha. Two control ponds had no tilapia. Tilipia stocking size had no effect on prawn growth. Mean weight of prawns after 70 days of culture ranged from a low of 4.5 g when cultured with tilapia fingerlings to a high of 6.6 when cultured in monoculture. Prawn survival was adversely affected by tilapia fry. Average prawn survival in tilapia fry ponds was 65% compared to 75% and 91%, respectively, in tilapia fingerling and monoculture ponds.
In a second experiment, postlarval prawns were stocked in nine 0.02 ha earthen ponds at 40,000/ ha. Six ponds were stocked with 30 g tilapia fingerlings, three at 5,000/ha and three at 15,000/ha. Three control ponds received prawns only. After 100 days of culture, prawn weight ranged from an average of 15.9 g in monoculture ponds to 11.5 g in polyculture ponds. Survival was highest (93.8%) in low density polyculture ponds. Survival was lowest (85.6%) in prawn monoculture ponds. Tilapia reproduction had a negative impact on shrimp production. 相似文献
In one experiment, postlarval prawns (av. wt. 0.02 g) were stocked in six 0.02 ha earthen ponds at 35,00O/ha. Two ponds were stocked with tilapia fry (av. wt. 0.14 g) and two were stocked with tilapia fingerlings (av. wt. 30.1 g), each at 10,000/ha. Two control ponds had no tilapia. Tilipia stocking size had no effect on prawn growth. Mean weight of prawns after 70 days of culture ranged from a low of 4.5 g when cultured with tilapia fingerlings to a high of 6.6 when cultured in monoculture. Prawn survival was adversely affected by tilapia fry. Average prawn survival in tilapia fry ponds was 65% compared to 75% and 91%, respectively, in tilapia fingerling and monoculture ponds.
In a second experiment, postlarval prawns were stocked in nine 0.02 ha earthen ponds at 40,000/ ha. Six ponds were stocked with 30 g tilapia fingerlings, three at 5,000/ha and three at 15,000/ha. Three control ponds received prawns only. After 100 days of culture, prawn weight ranged from an average of 15.9 g in monoculture ponds to 11.5 g in polyculture ponds. Survival was highest (93.8%) in low density polyculture ponds. Survival was lowest (85.6%) in prawn monoculture ponds. Tilapia reproduction had a negative impact on shrimp production. 相似文献
14.
北京地区养殖池塘底泥中重金属的分布及污染特征 总被引：4，自引：0，他引：4
调查结果显示,北京地区养殖池塘底泥中铬、铅、汞、锌、铜的含量分别为93.6(50.3~172)mg/kg(干)、32.2(20.1~185.8)mg/kg(干)、0.136(0.009~0.742)mg/kg(干)1、09.4(61.1~235)mg/kg(干)和57.8(18~155)mg/kg(干)。北京地区养殖池塘底泥中重金属含量相对较高,其中部分池塘中铜和汞的含量超过国家土壤环境质量Ⅱ级标准。采用单项污染指数法和综合污染指数法对北京地区养殖池塘底泥中重金属的污染状况进行了评价。北京地区养殖池塘底泥中铅的污染等级为安全级;锌的污染处于警戒线;铬、汞和铜为轻度污染。 相似文献
15.
Harrison Charo-Karisa Hans Komen Mahmoud A. Rezk Johan A.M. van Arendonk 《Aquaculture (Amsterdam, Netherlands)》2006,261(2):479-486
This study presents results of two generations of selection (G1 and G2) for growth of Nile tilapia. The selection environment consisted of earthen ponds which were fertilized daily with 50 kg dry matter (dm)/ha chicken manure. No supplementary feeds were provided. In total, 6429 fully pedigreed experimental fish were included in the analysis. Survival till harvest was highly variable ranging from 35% to 77% and was affected by initial weight, pond, and age effects. Body weight at harvest (BW) increased from a mean of 67.4 g in the grandparental (unselected) population (G0) to 129.5 g in G2 was affected by initial weight, pond, sex and age effects. Generations were discrete and therefore genetic parameters were estimated separately for each year. Heritability estimates for BW ranged from 0.38 to 0.60, and the heritability for survival ranged from 0.03 to 0.14. The estimated selection response was 23.4 g (34.7%) between G0 and G1 and 13.0 g (14.9%) between G1 and G2. These results demonstrate the feasibility of selection for growth of Nile tilapia in low-input environments. 相似文献
16.
Abstract— Australian red claw crayfish Cherax quudricarinurus were cultured in monoculture and in polyculture with male Nile tilapia Oreochromis niloricus in nine 0.02-ha earthen ponds. Red claw with an average weight of 7 g were stocked in all ponds at 2/ m2 . Tilapia with an average weight of 19 g were stocked in six ponds at either 0.5 or 1/m2 . A sinking 32% fish diet and dry alfalfa hay was provided to all ponds as feed and forage. After 135 d, red claw survival was similar (19–24%) in all treatments while average weights were 76 g in monoculture and 48 g in both polyculture treatments. Lower than expected survival was a result of stress caused by poor shipping conditions. Tilapia survivals were similar (84–90%) in all ponds and had an average weight of 403 g when stocked at 1/m2 and 444 g when stocked at 0.5/m2 . Red claws are generally considered non-aggressive, especially when compared with other clawed crustaceans. This lack of aggressiveness is suggested as a cause for decreased growth in polyculture with tilapia. 相似文献
17.
从4种常见微藻中筛选出能够充分利用木薯酒精废水及CO2废气生长的种类,并探究CO2体积浓度对其生长及净化废水中总氮(TN)、总磷(TP)、化学需氧量(CODCr)能力的影响。通过微藻在废水中生长的干重变化及叶绿素a(Chl-a)含量判断其生长情况,筛选出最适合的微藻。通过单因子试验,研究不同CO2体积浓度对筛选微藻的干重及叶绿素a(Chl-a)含量,以及CO2固定速率的影响,来寻找最适合生长的质量浓度。通过测定废水中TN、TP、CODCr的变化来评估净化作用。筛选试验结果表明,钝顶螺旋藻(Spirulina platensis)能适应酒精废水和CO2废气中的生长环境,在未经稀释的酒精废水中,其干重和Chl-a均显著高于波吉卵囊藻、普通小球藻和四尾栅藻(P<0.05)。单因子试验结果显示,当通入体积浓度2.5%的CO2,在酒精废水中培养的钝顶螺旋藻的干质量为(1.62±0.05)g/L、Chl-a为(12.1±0.7)mg/L,均高于其他试验组(P<0.05)。同时其对酒精废水中TN、TP、CODCr的去除率显著最高,分别为(50.5±2.1)%、(73.2±2.0)%及(24.9±0.6)%。钝顶螺旋藻能够适应酒精废水的生长环境,能吸收利用CO2废气,并有不错的净化效果。最适合其生长的CO2体积浓度是2.5%。 相似文献
18.
M. Asaduzzaman M.A. Wahab M.C.J. Verdegem M.N. Mondal M.E. Azim 《Aquaculture (Amsterdam, Netherlands)》2009,286(1-2):72-79
An on-station trial was conducted to evaluate the effect of stocking density of freshwater prawn and addition of different levels of tilapia on production in carbon/nitrogen (C/N) controlled periphyton based system. The experiment had a 2 × 3 factorial design, in which two levels of prawn stocking density (2 and 3 juveniles m? 2) were investigated in 40 m2 earthen ponds with three levels of tilapia density (0, 0.5 and 1 juveniles m? 2). A locally formulated and prepared feed containing 30% crude protein with C/N ratio close to 10 was applied considering the body weight of prawn only. Additionally, tapioca starch was applied to the water column in all ponds to increase C/N ratio from 10 (as in feed) to 20. Increasing stocking density of tilapia decreased the chlorophyll a concentration in water and total nitrogen in sediment, and increased the bottom dissolved oxygen. The concentrations of inorganic nitrogenous species (NH3–N, NO2–N and NO3–N) were low due to maintaining a high C/N ratio (20) in all treatment ponds. Increasing prawn density decreased periphyton biomass (dry matter, ash free dry matter, chlorophyll a) by 3–6% whereas tilapia produced a much stronger effect. Increasing stocking density of freshwater prawn increased the total heterotrophic bacterial (THB) load of water and sediment whereas tilapia addition decreased the THB load of periphyton. Both increasing densities of prawn and tilapia increased the value of FCR. Increasing prawn density increased gross and net prawn production (independent of tilapia density). Adding 0.5 tilapia m? 2 on average reduced prawn production by 12–13%, and tilapia addition at 1 individual m? 2 produced a further 5% reduction (independent of prawn density). The net yield of tilapia was similar between 0.5 and 1 tilapia m? 2 treatments and increased by 8.5% with increasing stocking density of prawn. The combined net yield increased significantly with increasing stocking density of prawn and tilapia addition. The significantly highest benefit cost ratio (BCR) was observed in 0.5 tilapia m? 2 treatment but freshwater prawn density had no effect on it. Therefore, both stocking densities (2 and 3 juveniles m? 2) of prawn with the addition of 0.5 tilapia m? 2 resulted in higher fish production, good environmental condition and economic return and hence, polyculture of prawn and tilapia in C/N controlled periphyton based system is a promising options for ecological and sustainable aquaculture. 相似文献
19.
Five pond management strategies for Nile tilapia Oreochromis niloticus L. production were evaluated in 0.1‐ha earthen ponds in Egypt during a 145‐day production cycle. Pond management strategies developed by the Pond Dynamics/Aquaculture Collaborative Research Support Programme (PD/A CRSP) were compared with a traditional and a modified Egyptian pond management strategy. Young‐of‐year Nile (mixed‐sex or sex‐reversed) tilapia were stocked into ponds at 20 000 fish ha?1. Sex‐reversed tilapia were stocked into chemical fertilization, organic fertilization plus formulated feed and feed only treatment ponds, whereas mixed‐sex tilapia were stocked into organic fertilization plus formulated feed and chemical plus organic fertilization plus formulated feed treatment ponds. Nile tilapia yields ranged from 1274 to 2929 kg ha?1. Nile tilapia yields in organic fertilization plus formulated feed treatments were significantly greater than the yield from chemical fertilization ponds. PD/A CRSP pond management strategies did not produce significantly greater Nile tilapia yields than the traditional Egyptian system, but a larger percentage of harvested tilapia in the organic fertilization plus feed treatments were classified in the first and second class size categories compared with the traditional Egyptian system. Organic fertilization plus formulated feed pond management strategies had the highest net returns, average rate of return on capital and the highest margin between average price and break‐even prices to cover total variable costs or total costs. 相似文献