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1.
《渔业科学进展》2016,(2)
通过实验室可控条件,以桑沟湾(Sanggou Bay)养殖海带(Sacharina japonica)为研究对象,探讨养殖海带碎屑降解过程中营养盐释放速率及对底质、溶解氧的影响。实验设置2个底质条件(加底泥,无底泥)、2个溶氧条件(好氧,厌氧),各处理组设3个平行,实验持续27 d。结果显示,(1)加入底泥,可以促进海带碎屑的降解。实验结束时,加入底泥组无机氮(DIN)、总氮(TN)、活性磷酸盐(DIP)、总磷(TP)的平均释放速率分别为1.234、1.802、0.028、0.033μmol/(g·d),显著高于未加底泥组的0.039、1.476、0.005、0.010μmol/(g·d)。而未加底泥组的可溶性有机氮(DON)释放速率为1.437μmol/(g·d),显著高于底泥组的0.568μmol/(g·d)。(2)厌氧条件有利于海带碎屑中P的降解释放,释放的TP中以可溶性有机磷(DOP)为主。TP、DIP、DOP的降解速率显著高于非厌氧条件。但是,厌氧条件下无机氮释放速率为0.097μmol/(g·d),仅为好氧条件下无机氮的8%,而总氮为好氧条件下的71%。(3)底泥的加入显著提高了水体的N∶P,达到207.83±301.37,厌氧状态使水体N∶P降低到9.38±6.55,都较大的偏离对照组的16.82±1.26,远远偏离经典Redfield值(16∶1)。整个实验说明养殖海带降解过程受底质、溶氧条件影响,同时,大量海带碎屑腐烂降解,将会对养殖系统的营养盐浓度及结构产生影响。 相似文献
2.
为了探究光照与营养盐对海带(Saccharina japonica)幼苗释放溶解有机碳(DOC)的影响,测定了不同光强[0、83、165和250 μmol photons/(m2·s)]和不同营养条件下(氮加富、磷加富、氮磷加富和自然海水)海带幼苗DOC的释放速率。结果显示,自然海水条件下,海带幼苗DOC释放速率与光照呈正相关性(P<0.05),光照250 μmol photons/(m2·s)时达到最高,为(24.31±5.84) μmol/(g·h),约为黑暗条件的4倍左右。单一氮加富、磷加富对海带幼苗释放DOC无显著影响,其释放速率分别为(23.04±4.23)和(18.18±4.59) μmol/(g·h)。氮磷共同加富显著提升了海带幼苗DOC释放速率,其释放速率为(37.15±6.77) μmol/(g·h),约为自然海水条件下的3倍。海带幼苗释放DOC很可能同时受“溢出”与“扩散”两种调节机制影响。在寡营养条件下,“溢出”机制占主导,表现为与光照正相关,释放物质相对分子量较高;在富营养条件下,“扩散”机制占主导,表现为受氮、磷营养盐整体水平调节,释放物质相对分子量较低。 相似文献
3.
封闭式精养池塘N、P营养盐的自净作用研究 总被引：1，自引：0，他引：1
以珠江三角洲的精养池塘为例,通过对一个养殖周期的水质和生产情况调查,计算了N、P营养盐的平衡收支情况,获得了养殖池塘N、P营养盐的净沉积速率,在此基础上分析了浮游植物对N、P吸收、底泥的吸附沉淀和底泥-水界面营养盐的扩散在池塘自净作用中的贡献。结果表明:养殖池塘N营养盐的自净作用主要来自浮游植物的吸收,强度达到0.35 g/(m2.d),扩散作用也是N营养盐的重要的自净机制,其强度与水体-底泥间隙水中的N营养盐浓度梯度相关,在优质鱼养殖池塘,扩散作用强度达到0.42~0.49 g/(m2.d),而在家鱼养殖池塘,呈现出反向的扩散,强度为0.02~0.10 g/(m2.d)。养殖池塘P营养盐的自净作用来自浮游植物的吸收、底泥的吸附沉淀,二者的强度分别达到0.049 g/(m2.d)、0.04~0.12 g/(m2.d),二者之和一般大于养殖鱼类无机P排泄速度0.079 g/(m2.d),底泥的P释放是维持水质稳定的重要过程,在观测的池塘中,P释放强度达到0.019~0.068 g/(m2.d)。 相似文献
4.
“海天1号”海带是南方耐高温品种与北方高产品种杂交后,经过几代选育获得的海带新品系,具有产量高、耐高温、成熟稍早等特点(暂命名为“海天l号”海带).为探究“海天1号”海带幼孢子体在不同环境因子下的生理适应性,设置了温度、光强及营养盐3个单因素实验,利用液相氧电极技术研究其对“海天l号”海带幼孢子体(1-2 cm)表观光合速率(Pn)和呼吸耗氧速率(R)的影响,并测定相对生长速率(Relative growth rate,RGR).结果显示:(1)温度为14℃、光强为80 μmolphotons/(m2.s)、氮营养盐为6 mg/L(N/P=10∶1,下同)环境下,幼孢子体的RGR和Pn均较大.在温度为22℃、光强为1 00 μmol photons/(m2·s)、氮营养盐浓度为10 mg/L条件下,R最强.(2) 22℃组的幼孢子体生长受到抑制,其RGR显著低于14℃组(P＜0.05).20 μmol photons/(m2·s)与80 μmolphotons/(m2·s)光强组的RGR存在显著性差异(P＜0.05).单因素方差分析显示,5个营养盐浓度组之间幼孢子体的RGR无显著性差异(P＞0.05).(3)随着温度、光强、营养盐浓度增加,幼孢子体的Pn呈先上升后下降的趋势,14℃组Pn显著高于其他温度组,氮营养盐浓度4 mg/L和6 mg/L组的Pn显著高于2、8和10 mg/L组(P＜0.05).在本实验条件下,R和Pn呈负相关.(4)光强对幼孢子体P/R(总光合速率/呼吸耗氧速率)的影响较小,温度和营养盐浓度对其影响较大.正交实验结果显示,适宜“海天1号”海带幼孢子体培养的条件为光强50 μmol photons/(m2·s)、温度16℃、氮营养盐浓度5 mg/L. 相似文献
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6.
运用脂肪酸标志法分析了海带新鲜组织、降解组织及脱落碎屑中定殖微型生物群落的组成特征。研究结果显示,降解组织和脱落碎屑的总脂含量显著提高,单不饱和脂肪酸和多不饱和脂肪酸相对含量降低。降解组织和脱落碎屑中细菌脂肪酸标志18∶1(n-7)和奇数碳及支链脂肪酸含量相比于新鲜叶片有大幅度的提高,表明碎屑中定殖了繁盛的细菌群落;海带碎屑的硅藻脂肪酸标志16∶1(n-7)/16∶0比值最高,降解组织中该比值也显著高于新鲜叶片,表明硅藻类也大量定殖于海带降解组织和碎屑中。鲜海带组织中不含原生动物脂肪酸标志——DHA,而在降解叶片和脱落碎屑中都检测到一定含量的该标志物(0.65%和1.57%),指示了原生动物在海带降解组织和碎屑中的定殖。各种微型生物的定殖与生物降解作用显著改变了降解海带叶片及海带碎屑的有机碳氮特征,新鲜海带叶片组织碳、氮比值高达17.32,而降解组织和海带碎屑有机氮含量有较大幅度的升高,碳、氮比值则分别下降为6.61和6.48。研究结果表明,海带脱落碎屑并非单一成分,而是以海带降解残片为主体,同时混杂有硅藻类、细菌和原生动物群落的混合体。海带碎屑通过各种微型生物的定殖与生物降解作用,其有机氮含量升高,碳、氮比... 相似文献
7.
海带对富营养化水体的生物修复效果与固碳能力 总被引：1，自引：0，他引：1
《中国渔业质量与标准》2015,(4)
选择舟山市桃花岛碳汇渔业示范区作为调研对象,于2013年2-8月对网箱养殖区、海带养殖区、海带养殖区上游(对照点)和海带养殖区下游各站位水质参数以及海带生物量的变化进行了为期7个月的跟踪调研。调查结果显示,海带在减轻海水富营养化方面效果显著,在去除海水无机氮方面尤为明显。与对照点相比,海带养殖区下游无机氮平均浓度降低了15.3%,水体富营养化得以改善,网箱养殖区海水与对照点相比,无机氮平均浓度显著降低(P0.05),海带养殖未使海水中有机质含量升高。在固碳能力方面,该海域海带的年固碳能力为0.234kg/m~2,通过标准化转换,固碳速率最高达403t/(km~2·年),通过海带养殖,该示范区一年总共可吸收碳(C)31 200 kg,吸收氮(N)2130 kg,吸收磷(P)300 kg。本研究说明海带具有一定的生物修复与固碳能力,可为建立鱼藻生态复合养殖系统提供参考。 相似文献
8.
厦门大嶝岛海域紫菜、海带养殖容量研究 总被引：1，自引：0，他引：1
以海域无机氮(N)和无机磷(P)输入与吸收的平衡原理,通过2000～2001年对厦门大嶝岛海域海水交换、沉积物释放、陆地和江河径流排放、养殖动物和野生海洋动物排泄等项无机氮和无机磷输入量的调查、检测,浮游植物、潮滩微型藻类、野生大型藻类、养殖和野生海洋动物对无机氮和无机磷吸收量的调查和检测,估算可供养殖海带和紫菜的无机氮和无机磷数量,进一步以海带和紫菜有机氮和有机磷的含量,来衡量海带和紫菜的可养殖量。估算结果表明,无机氮平衡法估算大嶝海域紫菜和海带养殖容量(淡干品)分别为5·43×104和32·84×104t,单位面积可养密度分别为7·21和43·61t·hm-2。无机磷平衡法估算大嶝海域紫菜和海带养殖容量分别为1·97×104和12·22×104t,单位面积可养密度分别为2·62和16·23t·hm-2。模型的实用性分析以无机磷供需平衡法为佳。 相似文献
9.
草鱼不同混养模式下围隔底泥反硝化、硝化和氨化速率 总被引：4，自引：0，他引：4
应用乙炔抑制法测定了草鱼(Ctenopharyngodon idellus)不同混养模式围隔底泥的硝化、反硝化和氨化速率,以探究草鱼不同混养模式对池塘底泥－水界面N元素动态变化的影响,并为草鱼养殖模式的优化提供必要的参考依据.混养组合分别为一元组（草鱼）、二元组（草鱼+鲢、草鱼+凡纳滨对虾）、三元组（草鱼+鲢+凡纳滨对虾,设2种放养比例）.结果显示:1）草鱼不同混养模式中底泥的反硝化速率范围为0～734.15 μmol/(m2·d),硝化速范围为0～1 209.20 mmol/(m2·d),化速率范围为0～41.25 mmol/(m2·d).2)草鱼不同混养模式底泥的反硝化速率较高,与很多河口和湖泊数值接近;在养殖中期,底泥的硝化速率很小甚至检测不到;底泥的氨化速率呈逐月递增趋势,以三元混养组最高.3）混养组中凡纳滨对虾(Litopenaeus vannamei)的放养密度越大,草鱼的放养密度越小,反硝化作用出现得越早,但反硝化速率很难保持开始的水平;反之,反硝化作用出现得较晚,并会随着养殖周期的推移迅速升高;放养种类越单一,底泥的硝化速率越低,且鲢(Hypophthalmichthys molitrix)放养密度越高,硝化速率越高.从养殖模式优化的角度来看,草鱼三元混养组要优于单养和二元混养组,但三元混养组中两种放养密度各有优劣,有待进一步优化以确定最佳放养比例. 相似文献
10.
采用沙子、活性炭与沸石作为生物滤器载体对牙鲆养殖废水进行处理。牙鲆体长10～15cm,在盐度30,pH8.0～8.1,水温(20±1)℃时的产氨速率为0.248g/(kg·d),产磷速率为0.537g/(kg·d),溶解有机物积累速率为1.406g/(kg·d)。以沙子、活性炭及沸石为载体的生物滤器对其废水处理的平均氨去除率分别为34.79g/(m~3·d)、35.60g/(m~3·d)和36.17g/(m~3·d),有机物平均降解速率分别为 1.760g/(m~3·d)、2.134g/(m~3·d)和2.420g/(m~3·d)。3种生物滤器对养殖废水都有明显的处理效果,其中沸石效果最好。 相似文献
11.
Liping Li Rui Wang Wanwen Liang Xi Gan Ting Huang Yan Huang Jian Li Yunliang Shi Honglin Luo Ming Chen 《广西水产科技》2014,(1)
Previously, we reported 10 PEGE types of 85 tilapia Streptococcus agalactiae(GBS), which shifted from Streptococcus iniae in China, by using PEGE method. Presently, larger and more representative tilapia GBS were isolated, for the ?rst time in China, to characterize their serotypes and genetic diversities more precisely than had done before. 168 GBS strains were distributed in ?ve provinces of China, in which Guangdong, Guangxi and Hainan were the major ones, holding36.9%(62/168), 37.5%(63/168) and 19.6%(33/168), respectively. Serotypes, Ia, Ib and III, were observed in these strains and the most predominant one was Ia(95.2%), which mainly distributed in Guangdong, Guangxi and Hainan. Ia initially occurred in 2009, it shoot up to 32.1% in 2010,but decreased to 16.1% in 2011 before went up to 45.2% in 2012. Ib sporadically occurred during2007–2011, III onlyoccurred in 2012. 14 different PFGE types, including 4 new types(N, O,P and Q), were observed, in which B, D, F and G were the predominant types, holding 83.9%(141/168) of the total GBS strains. Ia corresponded to 11 PFGE types(A–H, N–P), in which type D predominated(51%). Ib represented 3 genotypes(I, J and Q) and III harbored only 2genotypes(N and F). Type N and Fsynchronously presented in Ia and III. In summary, the genetic diversity of tilapia GBS varied by serotypes and changed with geographical locations and years.Although Iastillpredominated, new rareserotypeIII alreadyoccurred in China. 相似文献
12.
Two gonadotropins (GtH; Qa and Qb) were purified by gel filtration and ion exchange chromatography from the pituitaries of Indian walking catfish (Clarias batrachus). The presence of GtH during purification was assessed by in vitro oocyte maturation and in vivo steroidogenic activity, and their identities were determined by elution profiles, molecular weight, biological activities and yield. The molecular weights of Qa and Qb were 37 and 42 kDa, respectively, and composed of distinct subunits (Qa: 20 and 14 kDa and Qb: 26 and 18 kDa). Polyclonal antibodies raised against Qa immunostained Qa, Qb and pituitary GtH cells. A competitive Qa‐ELISA was developed whose sensitivity was 6.25 ng mL?1 (1.25 ng well?1) with intra‐ (3.5%) and inter‐ (12.4%) assay coefficients of variation. Displacement curves parallel to the standard were obtained with plasma and pituitary extracts of catfish, Qb and carp GtHII. The assay was validated by measuring the plasma Qa levels after LHRH treatment and in relation to ovarian growth in the female catfish during different reproductive phases. Based on the results, Qa and Qb corresponded to fish LH and FSH respectively. The findings will increase the knowledge of the mechanisms controlling fish reproduction and identification of sensitive phases in fish in captivity for hormonal manipulation. 相似文献
13.
Controlled infection of Poecilia reticulata Peters (guppy) with Tetrahymena by immersion and intraperitoneal injection 
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下载免费PDF全文 G Sharon M Pimenta‐Leibowitz M C L Vilchis N Isakov D Zilberg 《Journal of fish diseases》2015,38(1):67-74
Tetrahymena is a protozoan parasite, which infects guppy, Poecilia reticulata Peters, and causes substantial economical losses in commercial farms worldwide. Studies of guppy infected by Tetrahymena require standardized infection protocols. The LD50 for Tetrahymena infection of guppies by intraperitoneal (IP) injection was calibrated, and the level obtained was 946 parasites per fish. Guppy infection with Tetrahymena by immersion, imitating the natural route of infection via the integument, was studied under normal or stress conditions. Exposure to cold and netting (CNI) and to cold only (CI) followed by immersion exposure to 10 000 Tetrahymena per mL resulted in 22.5% and 19.2% mortality, respectively, as compared to 14.2% and 10% in groups that were netted only (NI) or non‐stressed (I). Histopathology revealed that immersion infection resulted in a systemic infection. Lysozyme levels, measured 3 weeks after infection, were significantly higher in the CNI group (288 μg per mg protein) compared with CI‐, NI‐ and I‐treated groups (94.5, 64 and 62.3 μg mg?1, respectively). There was no evident parasite immobilization activity in body homogenates, suggesting no development of acquired immunity. Re‐infection by IP injection revealed no increase in protection in any of the treatment groups, mortality range of 56.3–75%, higher than in the non‐exposed control (40.6% mortality). 相似文献
14.
There has been growing concern about the overuse of antibiotics in the ornamental fish industry and its possible effect on the increasing drug resistance in both commensal and pathogenic organisms in these fish. The aim of this study was to carry out an assessment of the diversity of bacteria, including pathogens, in ornamental fish species imported into North America and to assess their antibiotic resistance. Kidney samples were collected from 32 freshwater ornamental fish of various species, which arrived to an importing facility in Portland, Oregon from Colombia, Singapore and Florida. Sixty‐four unique bacterial colonies were isolated and identified by PCR using bacterial 16S primers and DNA sequencing. Multiple isolates were identified as bacteria with potential to cause disease in both fish and humans. The antibiotic resistance profile of each isolate was performed for nine different antibiotics. Among them, cefotaxime (16% resistance among isolates) was the antibiotic associated with more activity, while the least active was tetracycline (77% resistant). Knowing information about the diversity of bacteria in imported ornamental fish, as well as the resistance profiles for the bacteria will be useful in more effectively treating clinical infected fish, and also potential zoonoses in the future. 相似文献
15.
Effect of iodophor disinfection of non‐hardened Salmo trutta eggs on their bacterial and fungus load 下载免费PDF全文
下载免费PDF全文 Franz Lahnsteiner 《Aquaculture Research》2017,48(7):3901-3909
This study investigated the efficiency of iodophor disinfection (135 ppm active iodine for 15–30 min) of non‐hardened Salmo trutta eggs against different groups of bacteria and against fungus. Egg samples were taken from non‐disinfected and from disinfected eggs, microorganisms were cultured on specific nutrient media and their mass was measured by turbidimetric methods. Bacteria and fungus mass of non‐hardened eggs could be reduced but not eliminated by iodophor disinfection with 135 ppm active iodine for 15 min. The extent of reduction was 47–65% (Experiment 1). The efficiency of disinfection increased with disinfection time as the reduction in bacteria and fungus mass was 40–55% after 15 min and 58–74% after 30 min (Experiment 2). Disinfection efficiency of iodophor solution diluted in water (reduction 49–57%) and of iodophor solution diluted in sodium chloride solution iso‐osmolar to the oocytes (reduction 52–61%) was similar (Experiment 3). The reduction in bacteria and fungus mass was persistent as it was 39–72% lower in embryos deriving from disinfected eggs than in embryos deriving from non‐disinfected ones (Experiment 4). In conclusion, the tested disinfection method is inadequate to eliminate pathogens completely but it could positively influence immune defence of eggs and embryos. 相似文献
16.
T. Citarasu K. Venkatramalingam M. Micheal Babu R. Raja Jeya Sekar M. Petermarian 《Aquaculture International》2003,11(6):581-595
The indiscriminate use of antibiotics and chemicals in shrimp hatcheries has led to biomagnification and that in turn could
lead to rejection of a whole consignment. The application of the bioencapsulation technique as a tool for curative treatment
in shrimp larvae was investigated. Herbs having antibacterial properties such as Solanum trilobatum, Andrographis paniculata and Psoralea corylifolia (methanolic extracts) were bioencapsulated in Artemia and fed to Penaeus monodon post larvae PL 1–25. The post larvae were reared in a medium inoculated with pathogenic bacteria such as Pseudomonas aeruginosa, Staphylococcus aureus, Salmonella typhi and Vibrio sp. Post larvae reared in the non-inoculated water and fed with non-enriched Artemia exhibited 90% survival, highest specific growth rate (12.43%) and reduced bacterial load. P. monodon reared in the bacterial inoculated water and fed with the non-enriched Artemia exhibited the lowest survival (10–30%), specific growth rate (8.42–9.1%) and increased bacterial load (2.86 × 103 to 3.76 × 105 cfu/g). The methanolic extracts of the herbs helped to increase survival and specific growth rate and reduced bacterial load
in the P. monodon culture system. Among the three herbal extracts, P. corylifolia enriched Artemia fed post larvae showed the tendency to higher survival (>50%), growth rate (11.5 averaged) and low bacterial load (1.12 × 105 cfu/g).
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
17.
Effects of cortisol on hepatic carbohydrate metabolism and responsiveness to hormones in the sea raven,Hemitripterus americanus 总被引：2，自引：0，他引：2
The sea raven, Hemitripterus americanus, is a sit-and-wait, low metabolic rate, marine teleost. The objective of this study was to determine i) whether cortisol implantation (50 mg. kg-1) for 7 days altered hepatocyte metabolism, and hepatocyte responsiveness to epinephrine, glucagon and insulin, and ii) whether 8 weeks of food-deprivation modified the above response. Cortisol implantation significantly increased hepatocyte
total glucose production and oxidation from alanine compared to the sham group. There was no cortisol effect on glycogen breakdown,
suggesting that the activation of other pathways, including gluconeogenesis, are required to account for the increased glucose
production. Epinephrine-mediated (10-5M) glycogen breakdown and insulin-mediated (10-8M) total glucose production were enhanced in hepatocytes of cortisol implanted sea ravens, but there were no change in any
glucagon (10-7M) effects. The enhanced glycogen breakdown in the absence of similar increases in total glucose production with epinephrine
indicates mobilization of carbohydrate reserves for endogenous use by the liver.
Food-deprivation for 8 weeks significantly decreased condition factor, plasma cortisol concentration and liver glycogen content
in the sea raven, but had no effect on plasma glucose concentration. Hepatocyte total glucose production and flux rates from
alanine increased significantly with food-deprivation. Moreover, food-deprivation increased responsiveness of total hepatocyte
glucose production to the actions of glucagon and insulin, but not to epinephrine; none of these effects were modified by
cortisol implantation.
Our results indicate that cortisol in the sea raven exerts both a direct and an indirect or permissive effect on hepatocyte
metabolism by modifying hepatocyte responsiveness to epinephrine and insulin stimulation. Cortisol implantation did not modify
the effects of glucagon or food-deprivation in this species. 相似文献
18.
Simulation and quantification of enrichment and retention processes in the southern Benguela upwelling ecosystem 总被引：2，自引：0，他引：2
CHRISTOPHE LETT CLAUDE ROY ANNE LEVASSEUR CARL D. VAN DER LINGEN CHRISTIAN MULLON 《Fisheries Oceanography》2006,15(5):363-372
Important environmental processes for the survival and recruitment of early life stages of pelagic fishes have been synthesized through Bakun's fundamental triad as enrichment, concentration and retention processes (A. Bakun, 1996, Patterns in the Ocean. Ocean Processes and Marine Population Dynamics. San Diego, CA, USA: University of California Sea Grant). This conceptual framework states that from favourable spawning habitats, eggs and larvae would be transported to and/or retained in places where food originating from enrichment areas would be concentrated. We propose a method for quantifying two of the triad processes, enrichment and retention, based on the Lagrangian tracking of particles transported within water velocity fields generated by a three‐dimensional hydrodynamic model. We apply this method to the southern Benguela upwelling ecosystem, constructing putative maps of enrichment and retention. We comment on these maps regarding main features of the circulation in the region, and investigate seasonal variability of the processes. We finally discuss the results in relation to available knowledge on the reproductive strategies of two pelagic clupeoid species abundant in the southern Benguela, anchovy (Engraulis encrasicolus) and sardine (Sardinops sagax). Our approach is intended to be sufficiently generic so as to allow its application to other upwelling systems. 相似文献
19.
This study evaluated the effects of three levels of loading density (200, 300 and 400 g L−1) and four levels of duration (1, 3, 6 and 9 h) on the mortality, plasma cortisol and chloride levels and growth of rohu Labeo
rohita fingerlings in a transport simulation. While total immediate mortality was low (4–12%), delayed mortality was high (27–49%).
Initial capture and handling were found to constitute the most stressful phase as indicated by elevated plasma cortisol. The
levels of cortisol continued to rise at 6 and 9 h after transport, with the highest level observed at 9 h after transport.
The level of plasma chloride fell after transport across all density levels and treatment durations. Specific growth rate
(SGR, %/day) and total bacterial density (cfu/g) were not different between and within treatments, and between treatments
and the controls. This study demonstrates that transport has a profound effect on the stress responses of rohu fingerlings.
Although the level of immediate mortality was low, the higher level of delayed mortality has serious implications in terms
of production inefficiency for grow-out farmers. 相似文献
20.
Gabrielle C. Canonico Angela Arthington Jeffrey K. McCrary Michele L. Thieme 《水产资源保护:海洋与淡水生态系统》2005,15(5):463-483
- 1. The common name ‘tilapia’ refers to a group of tropical freshwater fish in the family Cichlidae (Oreochromis, Tilapia, and Sarotherodon spp.) that are indigenous to Africa and the southwestern Middle East. Since the 1930s, tilapias have been intentionally dispersed worldwide for the biological control of aquatic weeds and insects, as baitfish for certain capture fisheries, for aquaria, and as a food fish. They have most recently been promoted as an important source of protein that could provide food security for developing countries without the environmental problems associated with terrestrial agriculture. In addition, market demand for tilapia in developed countries such as the United States is growing rapidly.
- 2. Tilapias are well‐suited to aquaculture because they are highly prolific and tolerant to a range of environmental conditions. They have come to be known as the ‘aquatic chicken’ because of their potential as an affordable, high‐yield source of protein that can be easily raised in a range of environments — from subsistence or ‘backyard’ units to intensive fish hatcheries. In some countries, particularly in Asia, nearly all of the introduced tilapias produced are consumed domestically; tilapias have contributed to basic food security for such societies.
- 3. This review indicates that tilapia species are highly invasive and exist under feral conditions in every nation in which they have been cultured or introduced. Thus, the authors have concluded that, despite potential or observed benefits to human society, tilapia aquaculture and open‐water introductions cannot continue unchecked without further exacerbating damage to native fish species and biodiversity. Recommendations include restricting tilapia culture to carefully managed, contained ponds, although exclusion is preferred when it is feasible. Research into culture of indigenous species is also recommended.