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1.
对虾工厂化养殖和土池养殖溶解氧消耗研究   总被引:1,自引:0,他引:1  
对工厂化养殖凡纳滨对虾和土池养殖中国对虾过程中的各耗氧因子进行了研究。结果表明,在中国对虾的土池养殖环境中,对虾耗氧量、水柱和底质耗氧量分别占总耗氧量的3.749/6、17.359/6和78.919/6;在凡纳滨对虾的工厂化养殖环境中,对虾耗氧量占总耗氧的72.679/6,水柱耗氧占27.339/6。在对虾的工厂化养殖中,对虾耗氧是最大的耗氧因子;而土池养殖后期,底质耗氧是主要耗氧因子。  相似文献   

2.
虾池水质和底质的调查研究   总被引:1,自引:0,他引:1  
现场和实验室研究对虾养殖池水和底质,研究得到结果:虾池底质中有机质,硫化物和Eh随深度的变化,底质受残饵及对虾排泄物有机质污染,并与虾池养殖池龄有关,测定了虾池水质周日变化,下半夜水中溶解氧值最低。虾池水质在养殖过程逐渐下降,可能阻碍对虾生长,显示养殖存在自身污染的问题。  相似文献   

3.
皮坤  张敏  李保民  李庚辰 《水产学报》2018,42(2):246-256
为了探讨不同主养模式池塘养殖期间沉积物—水界面氮磷营养盐通量变化特征以及与环境因子之间的相互关系,利用沉积物—水界面营养盐扩散通量的原位观测装置,分析了2013年4—10月主养草鱼和主养黄颡鱼池塘沉积物—水界面营养盐交换通量,并探讨了影响营养盐交换通量的因素。结果发现:(1)在养殖初期,各种形态氮磷在养殖池塘沉积物—水界面主要表现为从上覆水向沉积物的沉积,养殖中后期,由于温度升高以及池塘沉积物中营养物质的大量累积,各种形态氮磷表现为以沉积物向上覆水扩散为主,表明池塘沉积物是氮磷营养盐的源与汇;(2)两种不同主养模式池塘氮磷通量的统计结果表明,沉积物—水界面-N、-N和-P通量变化无显著差异,而-N、TN和TP通量有显著差异;(3)上覆水中DO含量的升高显著促进界面间-N和-N释放通量,而-N和-P释放通量与上覆水DO浓度成显著负相关;温度的升高对各种无机形态的氮磷通量有显著的促进作用。  相似文献   

4.
桑沟湾养殖海区沉积物-海水界面氮、磷营养盐的通量   总被引:15,自引:1,他引:14  
20 0 2年 5月和 7月分 4个航次对桑沟湾养殖海区海底沉积物进行了底质与间隙水营养盐(NH+ 4,NO- 3,NO- 2 ,PO3- 4)的分析 ,并使用Fick第一定理对该海区沉积物 海水界面营养盐的通量进行了估算。研究结果表明 ,各站点间隙水三氮和磷酸盐的平面分布和垂直分布有较大的差异。用 4个航次的数据估算全年由沉积物向上覆水扩散的NH+ 4的通量为 376 33μmol/m2 ·d ,NO- 3、NO- 2 和PO3- 4的通量分别是 33 0 2、6 4 1、10 .0 8μmol/m2 ·d。估算桑沟湾全年由沉积物扩散进入上覆水的总无机氮的量为 2 81 7t,可以满足该湾浮游植物初级生产需要的 2 8 73% ,释放的无机磷的总量为 4 16 2t,可以完全满足该湾全年浮游植物的需求。研究结果为桑沟湾海湾沉积物 海水界面氮、磷营养盐的通量建模提供了重要数据 ,结论可以运用到规模化养殖海湾养殖容纳量的进一步研究之中。  相似文献   

5.
我国对虾养殖业快速发展,对发展我国农业生产,提高农民收入起着重大作用,但我国对虾养殖形势也很严峻,其最主要问题是发病严重,给对虾养殖产业带来了严重的影响。环境的恶化和底质污染是对虾发病最主要原因之一,为此,特谈谈改良底质在对虾养殖中的意义和方法,供参考。  相似文献   

6.
丁字湾养殖海域化学指标与营养状况的分析与评价   总被引:16,自引:1,他引:16  
本文根据1987年对虾养殖期间丁字湾海域的调查结果,以 IN、IP、COD和 DO为指标参数分析了该海域有机质和营养盐的污染状况和营养类型。分析结果表明,大面积对虾养殖排出的虾塘废水,能引起丁字湾海域有机质和营养盐的严重污染和富营养化,并且这种污染程度和营养类型有明显的季节变化。本文对丁字湾海域的赤潮能否形成也进行了预测。  相似文献   

7.
本研究采用碳—14同位素示踪法,测定对虾养殖水体中初级生产力的季节变化,并讨论了初级生产力与水化学环境主要参数pH,碱度,营养盐、重金属及温度,盐度的相互关系。  相似文献   

8.
南美白对虾养殖60 d后,也即到了养殖后期,在做好水质调控的同时,重点是改良虾池底质环境。底质的好坏直接影响水质,通常人们是通过水质的变化再知道底质的变化,改善底质是改善水质的基础。病原通过池底的有机污染物生长繁殖,再通过水体扩散传播。因此,养水先改底。  相似文献   

9.
在室内条件下进行了玉足海参与凡纳滨对虾的混养实验,分析了单养与混养两种条件下养殖水体营养盐结构以及底质成分的变化,测定了对虾与海参的存活率与生长性能。结果显示,混养海参可以明显改变养殖系统的营养盐结构,可使水体中的磷酸盐和硝酸盐浓度有所升高,同时也可有效地控制系统中氨氮浓度。混养海参也可以大幅度地降低沉积物中有机质和硫化物含量,实验结束时混养组硫化物含量为(7.71±1.33)mg/kg,仅相当于单养组浓度的1/3。混养海参对对虾生长及存活具有明显的促进作用,其中混养组对虾体长特异增长率为(0.69±0.13)%/d,显著优于单养组(0.45±0.06)%/d;混养组对虾成活率可达72.5%±22.9%,显著高于对照组55.0%±17.5%。在混养系统内,对虾不会对海参的生存造成负面影响,海参能够有效地选择摄食和利用沉积物中的营养物质(对食物中有机质的同化率可达36.36%±13.79%),并以较快的速度生长。结果表明,在对虾养殖系统中混养玉足海参具有明显的环境与经济效益。本研究可为我国海水养殖业的可持续发展提供一定的科学依据。  相似文献   

10.
为了使虾农在养殖南美白对虾过程中获得高产,现将南美白对虾健康养殖的技术要点概括如下:一、养殖环境1.虾池切断病源是对虾健康养殖的第一因素。虾池底质应彻底清塘消毒,并设有贮水池。经筛网过滤后的水首先进入贮水池消毒、沉淀,再进入放养池。清塘可采用塘克宁(水深15厘米,6~8亩,用1千克);底质的消毒可采用二溴海因、溴氯海因或生石灰。2.水体优良的水体是对虾健康养殖的根本保证。优良的水体应具备如下四大指标:酸碱度pH7.8~9.0;溶氧:不低于5毫克/升;氨氮小于0.5毫克/升、亚硝酸盐0.01毫克/…  相似文献   

11.
对虾养殖中新生残饵耗氧动态及其规律的研究   总被引:2,自引:0,他引:2  
本文根据实验模拟研究的结果,估算了由配合饵料和贻贝肉形成残饵后36天时间内的耗氧量,并讨论了其耗氧动态和规律。残饵耗氧量的变化范围为4.09~17.61g/kg·d。残饵耗氧曲线随残饵形成时间的不同而显著变化,且始终呈二次曲线衰减形式,在其演变过程中,该二次曲线方程的二次项系数由负数逐渐演变为正数,并最终接近于污染虾塘底质的耗氧曲线。配合饵料和贻贝肉的耗氧曲线变化形式相近,但程度上存在较大差异。另外,本文还初步探讨了残饵的耗氧高峰期,估算了残饵在虾塘底质总耗氧量中的作用。  相似文献   

12.
虾塘养殖水环境中氮磷营养盐的存在特征与行为   总被引:23,自引:0,他引:23  
孙耀 《水产学报》1998,22(2):117-123
根据现场调查结果,讨论了虾塘养殖水环境中氮磷营养盐的存在特征与行为,在该水环境中,IP的季节变化相对平稳,而IN则在养殖中后期变化幅度较大,IN和IP的垂直分布均匀;IN的形态分布有显著的季节变化,且与开阔浅海不同,NO2N也成为IN的主要存在形态,IN与IP比值始终较低,且IN在虾养殖期间的大部分时间内都处于贫瘠水平,从而构成该养殖水环境中初级生产的限制因素,而相对较高密度的浮游植物,则是缩短该  相似文献   

13.
乳山湾表层沉积物质量现状及其评价   总被引:7,自引:4,他引:3  
对乳山湾东流区表层沉积物的综合调查分析表明,乳山湾东流区为弱还原环境。总氮、总磷局部超标,且其含量与有机质、硫化物的变化特征相似,有明显的区域分布,在东部湾顶虾池排放口附近含量相对较高,说明养殖排放污水对其沉积环境质量有一定的影响。沉积物中的重金属以Cd的污染指数最大,平均值为32.54,其他重金属指标的污染指数较低,均小于1.0,说明乳山湾沉积物中存在Cd的潜在污染危险。  相似文献   

14.
白斑综合征病毒(WSSV)在拟穴青蟹体内增殖的研究   总被引:1,自引:0,他引:1  
拟穴青蟹(Scylla paramamosain)因肉质鲜美、生长快速而成为我国主要的海水养殖经济蟹类,但是随着养殖规模的不断扩大,病害问题也越发严重。本研究通过流行病学调查和定量PCR跟踪检测的方法,研究了拟穴青蟹对白斑综合征病毒(WSSV)的易感性和WSSV在拟穴青蟹体内的增殖情况。结果表明,拟穴青蟹是WSSV的自然宿主,自然携带率为8.47%。WSSV可通过口服途径感染拟穴青蟹,并在拟穴青蟹体内快速增殖,注射感染5 d后,病毒量达到感染1d时的1.1×109倍,当病毒累积到一定量后即可致死拟穴青蟹。研究表明,拟穴青蟹是WSSV的天然宿主,在虾蟹混养过程中可以通过摄食WSSV感染虾而带毒或发病,并因此成为WSSV传播媒介,从而对虾蟹混养条件下WSSV的防治效果产生重要影响。  相似文献   

15.
The sediments from four areas that are used or will be used for shrimp culture were evaluated for their effect on post‐larvae growth of Litopenaeus stylirostris. Texture, organic matter, total, and bio‐available fraction of phosphorus, manganese, iron, zinc, copper, and cadmium of the sediments were measured. A positive significant correlation was obtained between total and bio‐available concentrations of iron, cadmium, and manganese, but not for copper, phosphorus, or zinc. Significant differences in final weight, survival rates, and shrimp yield were obtained among treatments. The highest survival rates were obtained with sediments that had the highest manganese levels. This survival high rate was significantly correlated with total manganese content of the sediment (r=0.92). The highest final weight were obtained in treatments with sediments containing higher levels of phosphorus, which was reinforced by a significant positive correlation between final weight and total and bio‐available phosphorus (r=0.94 and 0.95 respectively), while final weight seems adversely affected by high concentrations of copper (r=?0.83) in the sediment. Texture of the sediment influenced shrimp yield, with lower values for sandy sediments relative to silty sediments.  相似文献   

16.
ABSTRACT:   A pelagic bacterial community structure was examined in experimental intensive shrimp culture ponds that have a shrimp–mangrove complex aquaculture system, an extensive shrimp culture pond and a mangrove area in Thailand by denaturant gradient gel electrophoresis analysis of polymerase chain reaction amplified partial 16S rRNA genes. Bacterial community structure in the intensive shrimp culture ponds was distinguishable from that of the mangrove area. In the extensive shrimp culture pond, the bacterial community structure resembled that in the mangrove area, but bacterial abundance was as great as that in the intensive shrimp culture ponds. Among the intensive shrimp culture ponds, the bacterial community structure was different between a closed culture system and a shrimp–mangrove complex culture system. Moreover, the bacterial community structure in mangrove planted ponds was close to those in the intensive shrimp culture ponds when shrimp culture was conducted, but it was close to those in the mangrove areas without shrimp culture. These results suggest that intensive shrimp culture with shrimp feed input affects the bacterial community structures in pond water.  相似文献   

17.
Most shrimp farmers in Chantaburi Province, Thailand, use water jets to dislodge sediment from empty pond bottoms, and wastewater is held for sedimentation before discharge into natural waters. Other pond bottom management practices used by a few farmers are sediment excavation, leave sediment but till entire pond bottom, and no mechanical treatment. All four methods of pond bottom treatment are followed by sun drying for 30 d. Soil organic carbon concentration in ponds following dry‐out seldom exceeded 2%. Although shrimp production in 24 ponds supplied by the same source of water was negatively correlated with increasing soil organic carbon concentration (r = ?0.582), this observation does not confirm a causative relationship. Moreover, in trials conducted at Burapha University, Chantaburi Campus, bottom soil organic matter concentration following dry‐out differed little irrespective of treatment method. Lower soil moisture concentration revealed that dry‐out was more complete with sediment removal than without, but better dry‐out resulted in lower soil pH. Removal of sediment by excavation or flushing is expensive, and natural dry‐out combined with liming and occasional sediment removal should be investigated as a less expensive and more environment‐friendly alternative to removing sediment after each crop.  相似文献   

18.
Biological water purification grid (BWPG), a type of biofilm, could increase aquaculture production by improving the growth of shrimp and culture environment. In this study, the microbial community composition and diversity of water, sediment and shrimp intestine were analysed using the Illumina Miseq high‐throughput sequencing technique. Installation of BWPG did not only increase the dissolved oxygen, pH and decreased inorganic nutrients, but also increased shrimp body length by 5.39% and weight by 16.35%. Furthermore, it was found that the microbial community diversity of water and shrimp intestine in test pond with BWPG was higher than that of control pond without BWPG. Cyanobacteria, Bacillus and Lactococcus were enriched in the test pond with BWPG. However, Rhodobacter was mainly identified in the test pond. It thus seems to suggest that the application of BWPG in shrimp culture pond enhanced the microbial species richness, types of species and proportion of beneficial bacteria in culture environment as well as shrimp intestine. The results from this study will therefore provide some scientific basis for the improvement and development of shrimp aquaculture.  相似文献   

19.
Consecutive failure of the improved extensive shrimp farming system has deterred the economy of some coastal areas in Vietnam. To investigate pond physico‐chemical characteristics, a monitoring scheme was performed in the Cai Nuoc district of Southern Vietnam. Results show that the system was not optimal for shrimps. While ponds were not contaminated by organic loadings or major nutrients (N, P) and salinity and pH were most optimal for shrimp, more than 37% of dissolved oxygen (DO) measurements were lower than recommended. In the early morning hours, DO measurements were even much lower (0.84–2.20 mg L?1). Sulphate (SO42?) concentrations were most within the acceptable range. Total suspended solids (TSS) were above the acceptable limit (<50 mg L?1). Iron, alkalinity and hydrogen sulphide were also higher than recommended. Pond sediment was anaerobic (redox potential ?422 to ?105 mV) and contained high amounts of organic matter (9.84–21.96%). Lethal DO levels, high TSS and anoxic sediment are the drawbacks in this system. Suggested measures to improve pond conditions are (1) allowing sedimentation before filling culture ponds, (2) covering dikes, (3) including no‐culture breaks between shrimp crops, (4) drying pond bottom, (5) removing sediment and (6) controlling pond's vegetation.  相似文献   

20.
强降雨对粤西凡纳滨对虾养殖池塘微生物群落的影响   总被引:1,自引:0,他引:1  
于强台风"莫拉菲"环流云系带来的持续强降雨天气前后(2009年7月14日和7月28日),对广东省茂名市电白县凡纳滨对虾半集约化养殖土池的水样和泥样进行调查,研究施用微生态制剂和未施用微生态制剂的虾池水体及底泥中的异养细菌、弧菌和芽孢杆菌的变化情况,并利用BIOLOGECO微板对水体和底泥的微生物群落代谢变化进行探讨。结果发现,定期施用微生态制剂的虾池水体和底泥中的细菌数量和微生物群落功能在强降雨前后基本保持稳定;未施用微生态制剂的虾池在强降雨后,水体的弧菌数升高,Simpson指数和McIntosh指数显著降低(P0.05),水体和底泥微生物群落对碳源的利用率变化明显。研究结果表明,与施用微生态制剂的虾池相比较,未施用微生态制剂的虾池在强降雨后,水体及沉积物环境波动变化明显,强降雨对其水域环境产生很大的影响。因此建议在对虾养殖过程中定期施用微生态制剂,并针对恶劣天气采取有效措施,以稳定虾池水体及沉积物的微生物生态。  相似文献   

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