首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到19条相似文献,搜索用时 187 毫秒
1.
柘林湾沿岸对虾养殖环境的氮磷负荷与区域分布   总被引:3,自引:0,他引:3  
研究了柘林湾沿岸对虾养殖产生的环境氮磷负荷及其来源的数量和比例.2006年柘林湾沿岸对虾养殖产生的环境氮负荷为210.21 t,其中来源于对虾的排泄氮、粪氮和残饵氮分别为157.10 t、39.61 t和13.50 t;环境磷负荷为45.45 t,其中排泄磷、粪磷和残饵磷分别为4.93 t、24.87 t和15.65 t.对虾养殖环境氮负荷主要来源于对虾的排泄,占氮负荷的74.74%,而磷负荷主要源自粪便,占磷负荷的54.72%.柘林湾沿岸对虾养殖的环境氮磷负荷量以湾北部沿岸最大,北部、西部和东部沿岸环境氮负荷分别为144.86 t、53.99 t和11.36 t,环境磷负荷分别为31.32 t、11.68 t和2.46 t.  相似文献   

2.
对虾池残饵、粪便及死虾腐解对养殖水质影响的模拟试验   总被引:7,自引:0,他引:7  
祁真  杨京平  刘鹰 《水产科学》2004,23(11):5-8
试验结果表明:(1)充气不仅能为对虾养殖提供充足的氧气,还能加速氨氮、亚硝态氮的氧化分解,两者间有显著差异(P<0 05);(2)投饵或对虾死亡前9h是管理NH3-N、NO2-N的关键时间,水质恶化加快;(3)残饵、排泄物及死虾三者相比,残饵是引起水质恶化的关键因子,而死虾对水质的影响很小。在对虾高密度养殖中应尽量减少残饵的残留量。  相似文献   

3.
养殖水体富营养化是现今凡纳滨对虾养殖面临的问题,水体富营养化主要是养殖环境中浮游植物过量生长,深层次的原因是对虾养殖中过量的投饵及高密度的养殖模式等导致水体中氮、磷等元素含量增高,产生一些对对虾有害的水质因子.贝类可以以水中的浮游植物作为饵料,多鳞作为底层鱼可以摄食水体的残饵及有机物,在凡纳滨对虾养殖过程中搭配一定密...  相似文献   

4.
整理统计了莱州湾主要有机污染物入海通量,并于1998年7月,调查了莱州湾湾顶部对虾养殖区进、排水中氮、磷及COD的浓度,初步估算出了对虾病害发生后(1993年),对虾养殖过程中排入海中COD的增量增量平均约为1173.4t/a,为黄河年排放量的0.54%,小清河年排放量的0.29%;无机氮的增量平均为45.1t/a,为黄河年排放量的1.79%,小清河年排放量的1.10%。对虾病害发生后(1993年后)莱州湾沿岸对虾养殖的有机污染较黄河和小清河小的多。  相似文献   

5.
对虾养殖在高效益的驱驶下。沿岸开发对虾养殖池塘,不少地区出现超负荷。加之养殖管理不规范,养殖废水任意排放,池塘残饵和对虾的排泄物大量增加,池塘底部污泥的沉积。  相似文献   

6.
吴琴瑟 《河北渔业》2012,(6):22-23,46
我国对虾养殖池塘多数是20世纪80- 90年代建造的,当前虾塘建造标准低,面积大、水浅,配套不规范,经过长时间的养殖,淤泥沉积,池塘污染老化严重,病害多、产量低.尤其近年来追求高产高效,养殖密度不断增加,造成池塘的残饵增加,生物排泄物及尸体等腐烂、分解,引起水质和底质的恶化,使水中营养元素的氮、磷等发生非正常变化,并产生氨氮、硫化氢、亚硝酸盐等有害物质,造成对虾池塘污染日益严重.破坏了虾塘原有的生态平衡.养殖对虾疾病不断发生,放虾苗后多次失败排塘,养虾难于成功,有的虾农谈虾色变,对养好虾缺乏信心.为何对虾养殖疾病多?往往对池底沉积物的危害性认识不足,未能采用有效的措施进行清除.因此,要养好虾,要在对虾养殖前,整治好旧虾塘的底质,底质的好坏直接影响到水质,只有底质好,才能水质好,"养水先改底".整治与修复好底质是养虾成功的首要环节.  相似文献   

7.
养殖密度对工厂化对虾养殖池氮磷收支的影响   总被引:5,自引:0,他引:5       下载免费PDF全文
本实验设置300尾/m3、600尾/m3、1 200尾/m3和1 800尾/m3 4个养殖密度,探讨了工厂化对虾养殖池中养殖密度对氮磷收支的影响.结果表明,饵料对系统氮、磷的贡献率分别为84.3%~98.3%和93.2%~97.3%,且随养殖密度的增加而提高;通过水层输出的氮、磷分别为总输出量的27.5%~36.3%和8.4%~23.9%,通过底泥沉积的氮、磷分别为总输出量的30.9%~43.9%和51.5%~62.3%.结果说明,在系统氮磷的总输出中,水层输出和沉积均占到了相当的比重,相比较而言,沉积作用更为重要.养殖密度增加会在一定程度上降低水层和提高底泥沉积的氮磷量;总氮磷的投入中有14.5%~28.7%的氮和7.4%~16.5%的磷最终转化为对虾生物量,表现为随养殖密度的增加而降低;池壁附着物中积累的氮磷量在总氮磷输出中所占比重较小,分别为0.3%~3.2%和0.2%~3.0%,且其比重随养殖密度的增加而降低.结果说明,养殖密度显著影响对虾工厂化养殖池氮磷的收支.  相似文献   

8.
海水养殖环境生物修复枝术研究展望   总被引:54,自引:1,他引:54  
自 8 0年代开始 ,对虾养殖、贝类养殖及浅海网箱养殖先后兴起 ,几乎遍及沿海所有可开发的滩涂和海湾 ,使我国成为世界养殖产量第一的水产大国。由于养殖方式以投饵为主 ,残饵、粪便及生物残骸堆积在养殖池底或近海滩涂 ,使得养殖水域有机污染不断加重 ,环境质量逐年恶化。袁有宪[1]曾计算 ,生产 1t对虾水中可残留粗蛋白 1 .3t ,说明对虾养殖业的污染主要是有机氮污染。袁有宪等 ① 对我国黄渤海沿岸重要对虾养殖区进行的环境质量调查结果表明 ,黄渤海对虾养殖区部分虾池水体的COD指标超过国家二类 ,甚至三类海水水质标准 ,池底有机污染…  相似文献   

9.
正海水多营养层次生态养殖技术是指通过引入鱼、虾和贝养殖品种,鱼类生活在水体中下层,虾和贝生活在水体下层,充分利用了水体空间。鱼类摄食对虾的残饵、粪便等有机物,降低了水体化学耗氧量。对虾和贝类在埋栖运动和呼吸时,可以增强底泥和水体的气体交换,促进底泥有机物质的氧化和无机盐的释放,提高虾池氮、  相似文献   

10.
水产养殖使用优质高效饲料的必要性   总被引:2,自引:0,他引:2  
<正> 近年来,水产养殖对养殖水体造成的自身污染已引起了人们的重视。研究表明,低品质饲料的使用是养殖水域环境恶化的最主要原因。通常,低质饲料的稳定性差,利用率低,投喂后必然造成饲料中营养素的溶失,残饵和鱼、虾、贝等排泄物的增多,最终加重水体的负荷。据报道,饲料中仅有50%的磷、15%~22%的氮被同化,而有50%的  相似文献   

11.
凡纳滨对虾高位池养殖氮、磷收支研究及养殖效果分析   总被引:5,自引:1,他引:5  
对凡纳滨对虾(Litopenaeus vannamei)高位池养殖氮(N)和磷(P)收支情况进行系统研究,比较分析不同放养季节、虾苗品系以及是否进行分段养殖引起养殖效果的差异。结果显示,饲料是最主要的N和P输入源,分别占池塘N和P总输入的91.76%~93.68%和94.55%~96.97%。收获对虾输出N和P分别占总输入的29.46%~40.46%和12.64%~17.41%,随养殖废水排出的N和P分别占24.63%~54.52%和23.03%~59.02%,沉积在池塘底部的N和P分别占14.10%~44.59%和27.59%~62.25%。放养季节和虾苗品系对养殖效果有显著影响。夏季组(ZS)对虾平均生长速度达到0.175g.d-1,分别比秋季组(ZF)和冬季普通组(ZW)高73.0%和139.3%。ZW成活率77.70%~87.75%,显著高于ZS和ZF。与相同养殖季节放养一代苗的ZW相比,放养本地苗的冬季组(BW)养殖成活率62.10%~72.30%,单位面积产量8821~9878kg.hm-2,均显著较低。采用分段养殖的冬季标粗组(ZWb)养成池塘单造使用周期缩短56.13%。  相似文献   

12.
牛津  赵伟 《水产学报》2022,46(10):1776-1800
凡纳滨对虾(Penaeus vannamei)是我国最主要的海水对虾类养殖品种,2021年海水养殖产量达到119.77万吨,占全国海水虾类养殖总产量的80%以上。目前,国内外对于凡纳滨对虾的营养需求与饲料研究已有较多报道,但是对于不同生长阶段的精准营养需求以及营养素和功能性饲料添加剂的相互关系研究仍不够深入。本文主要就其蛋白质、脂肪、碳水化合物和微量营养素的需求,蛋白源和脂肪源替代鱼粉和鱼油,功能性饲料添加剂应用等方面的研究进展进行综述,以期为凡纳滨对虾的精准营养研究及高效环保饲料的开发提供科学参考,从而推动其养殖业的健康可持续发展。  相似文献   

13.
粤东柘林湾浮游植物群落组成及水体营养盐分布特征   总被引:3,自引:0,他引:3  
2003年4月对粤东柘林湾进行的浮游植物及营养盐调查结果表明,柘林湾海域采集浮游植物59种、属,其中硅藻为优势类群,中肋骨条藻、丹麦细柱藻和窄隙角毛藻为海区优势种。浮游植物数量分布呈湾外向湾内递减趋势。调查海域柘林湾的SiO2 3表现为保守性行为,其分布主要是受物理因素的影响;PO3 4的行为是非保守性的,受浮游生物的影响较大;DIN的含量较高,超过国家三类海水的水质标准。如以Justic和Dortch等提出的营养盐限制因子标准来衡量,柘林湾海域浮游植物生长主要是受控于磷因子的限制。  相似文献   

14.
A nutrient budget of some intensive marine shrimp ponds in Thailand   总被引:17,自引:0,他引:17  
Abstract. A mass balance was constructed for nutrient flow through intensive marine shrimp ponds in which budgets for nitrogen and phosphorus were determined for a series of ponds in southern Thailand over two or three culture cycles. Ninety-five per cent of the nitrogen and 71% of the phosphorus applied to the ponds was in the form of feed and fertilizers. Of the feed input (at a food conversion ratio of 2) only 24% of the nitrogen and 13% of the phosphorus was incorporated into the shrimp harvested, whilst the remainder was retained in the pond and ultimately exported to the surrounding environment. The effluent water contained 35% of the nitrogen and 10% of the phosphorus discharged. Of the N and P exported in this effluent, 63–67% occurred during routine water exchange and the remainder during drainage on harvest. A major portion of the nitrogen (31%) and most of the phosphorus (84%) was retained in the sediments, emphasizing the importance of the correct removal and disposal of sediments between crops. Pond age (between two and six production cycles) did not markedly affect nutrient flows, whilst increasing stocking density increased the quantity of nutrients, but not their relative proportions.
The results derived from the nutrient budget provide data which may help define effective management techniques for reducing potentially harmful nutrient levels within intensive shrimp ponds, and for reducing the discharge of nutrients to the local environment. The data may also assist in determining the carrying capacity of an area for shrimp farming, and the potential impact of its development on the environment.  相似文献   

15.
不同密度的石莼与中国对虾的混养实验   总被引:37,自引:0,他引:37       下载免费PDF全文
王吉桥 《水产学报》2001,25(1):32-37
在10个水族箱(53cm×24cm×23cm)中各放养中国对虾(Penaeuschinensis)4尾,混养孔石莼(UluaPertysavar)0、4g、6g、8g和10g,采用投饲精养.结果表明,孔石莼能有效吸收N、P营养盐,提高对虾对饲料中氮的利用率(42.7%~212.9%),水质状况也优于单养对虾.混养的综合养殖指数高于单养对虾.对虾密度为320-480g@m-3,石莼密度为400~600g@m-3时,可以进行免充气养殖.  相似文献   

16.
An experiment was conducted in six earthen ponds with 20 shrimp/m2 ( Litopenaeus stylirostris ) during the cold season in New Caledonia to determine the effect of water exchange rate on characteristics of effluents and pond sediment. The nitrogen budget was established, taking into account the different forms of nitrogen in the water, sediment, feed, and shrimp. Mean water exchange rates ranged from 10 to 23% per day. Increasing water exchange rate did not cause any significant change in the average quality of the rearing environment (water and sediment) during the whole growout period. However, the results showed that increasing exchange rates boosted primary productivity. Compounds produced by the mineralisation and metabolism of organic matter (feces, uneaten feed) were exported as particulate, rather than soluble matter. The nitrogen budget showed that the amount of exported wastes from the pond into the coastal environment was only 40–50% of nitrogen inputs due to nitrogen accumulation in the pond sediments and/or release to the atmosphere. The highest accumulation of dry material, as well as the highest Δ N (concentration of total N at the end of rearing - concentration of total N before rearing), was observed in ponds with the highest WER.  相似文献   

17.
A phosphorus budget for a single crop was prepared for a 685‐ha semi‐intensive shrimp farm that consistently has produced about 3000 tonnes/yr of black tiger prawn, Penaeus monodon. Phosphorus inputs were shrimp stock, 0.31 kg/ha; triple superphosphate, 1.38 kg/ha; incoming water, 25.8 kg/ha; and feed, 65.3 kg/ha. Phosphorus outputs were harvested shrimp, 5.43 kg/ha, and outflow for water exchange and draining, 42.7 kg/ha. The high clay‐content soil in pond bottoms adsorbed 45.2 kg/ha of phosphorus. Water was taken from and released back into the same estuary and bay. The phosphorus contribution of shrimp farming to the receiving water body was the difference between the amount of phosphorus in effluent and that in the incoming water, which was 16.9 kg/ha. Bottom soil accumulated 67.8% of phosphorus added to the ponds. Another estimate of soil phosphorus uptake based on the relationship between cumulative phosphorus applied to ponds as fertilizer and feed and soil phosphorus concentration suggested that 63.2% of fertilizer and feed phosphorus had accumulated in pond bottoms. The farm effluent phosphorus load was 23.5 tonnes/yr. The estuary and bay system has an estimated volume of 4.8 × 109 m3, and the annual phosphorus input from the farm had a concentration equivalent of 0.005 mg/L, and there were no other major inputs of phosphorus. The estuary and bay are flushed by freshwater inflow and tidal action, and the farm input is not likely to cause eutrophication.  相似文献   

18.
Increasing feeding rates may provide an increase in production, thus nutrients such as nitrogen, phosphorus and organic matter will also increase. These nutrients promote a greater oxygen demand and concentrations of toxic metabolites which can lead to frequent problems with low dissolved oxygen and an abundance of blue‐green algae. Four feed management practices were evaluated among sixteen 0.1 ha ponds culturing Pacific white shrimp (Litopenaeus vannamei). Feeding treatments included hand feeding using the Standard Feeding Protocol (SFP), SFP plus 15% from 8 to 16 weeks, an automatic‐solar timer which fed SFP+15%, and an AQ1 acoustic demand feeder allowing up to 12 kg/day·pond based on shrimps feeding response. Samples were analysed at weeks 0, 4 and 8–16 for the following parameters: chlorophyll a, total ammonia nitrogen, nitrite–nitrogen, nitrate–nitrogen, total nitrogen, total phosphorus, soluble reactive phosphorus, total suspended solids, total suspended volatile solids, turbidity, conductivity, salinity and biological oxygen demand. Samples were collected and shipped overnight to Auburn, Alabama for off‐site analysis. On‐site water quality was also obtained at the farm. The AQ1 acoustic demand feeder produced the most shrimp with a yield of 4,568 kg/ha; however, the AQ1 also had the highest total ammonia nitrogen and nitrite–nitrogen levels late in the growing season. The AQ1 feeder may be a viable, reduced labour and cost alternative for the shrimp commercial industry; however, such technologies must also be matched to the ability of the production system to process nutrients.  相似文献   

19.
采用低频率运转循环水处理系统(含粗滤器、臭氧仪、气液混合器,蛋白分离器、暗沉淀池等)联用池内设施(微泡曝气增氧机与净水网)开展凡纳滨对虾室内集约化养殖实验。研究了养虾池以水处理系统调控水质效果及氮磷收支。结果表明,养虾水经系统处理后,NO2-N(53.4%~64.5%)、CODMn(53.4%~94.4%)与TAN(31.6%~40.4%)被显著去除,有效改进虾池水质;养殖周期内未换水与用药,虾池主要水化指标均控制在对虾生长安全范围,7号实验池(100 d)与8号对照池(80 d)主要水化指标变化范围:DO分别为 5.07~6.70 mg/L和4.38~6.94 mg/L,TAN 0.248~0.561 mg/L和0.301~0.794 mg/L,NO2-N 0.019~0.311 mg/L和0.012~0.210 mg/L,CODMn 10.88~21.22 mg/L和11.65~23.34 mg/L。7号池对虾生长指数优于8号池(80 d虾病暴发终止),单位水体产量分别为1.398 kg/m2与0.803 kg/m2。氮磷收支估算结果:7号与8号池饲料氮磷分别占总收入:氮93.70%与92.37%,磷98.77%与99.09%;初始水层与虾苗含氮共占总收入6.30%与7.63%,磷共占1.23%与0.91%。总水层(含排污水)氮磷分别占总输出:氮56.45%与59.86%,磷53.26%与55.79%;收获虾体氮磷分别占总输出:氮37.07%与31.94%,磷21.37%与13.11%。7号池饲料转化率较高;池水渗漏与吸附等共损失氮磷分别占总输出:氮7.00%与9.34%,磷25.37%与31.10%。实验结果表明,虾池以低频率运转循环水处理系统联用池内设施可有效控制水质与虾病,具较高饲料转化率。  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号