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Vasin Yuvanatemiya Claude E. Boyd Patana Thavipoke 《Journal of the World Aquaculture Society》2011,42(5):618-632
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
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The Potential Use of Mangrove Forests as Nitrogen Sinks of Shrimp Aquaculture Pond Effluents: The Role of Denitrification 总被引:4,自引:0,他引:4
Victor H. Rivera-Monroy Luis A. Torres Nixon Bahamon Federico Newmark Robert R. Twilley 《Journal of the World Aquaculture Society》1999,30(1):12-25
A generalized nitrogen budget was constructed to evaluate the potential role of mangrove sediments as a sink for dissolved inorganic nitrogen (DIN) in shrimp pond effluents. DIN concentrations were measured in pond effluents from three semi-intensive shrimp ponds along the Caribbean coast of Colombia between 1994–1995. Mean NH4 + concentrations in the discharge water for all farms were significantly higher (67 × 12 μg/L) than in the adjacent estuaries (33 × 8 μg/L). Average NH4 + concentrations in the pond discharge over all growout cycles were similar, representing an approximate doubling in relation to estuarine water concentrations. In contrast, NO2 - + NO3 - concentrations were similar in both pond effluent and estuarine waters. Dissolved inorganic nitrogen loading of the ponds was similar. The estimated reduction of DIN in pond effluents by preliminary diversion of outflow to mangrove wetlands rather than directly to estuarine waters would be × 190 mg N/m2 per d. Based on this nitrogen loss and depending upon the enrichment rate, between 0.04 to 0.12 ha of mangrove forest is required to completely remove the DIN load from effluents produced by a 1-ha pond. 相似文献
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Economics of Sustainable Intensification of Aquaculture: Evidence from Shrimp Farms in Vietnam and Thailand
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Carole R. Engle Aaron McNevin Phoebe Racine Claude E. Boyd Duangchai Paungkaew Rawee Viriyatum Huynh Quoc Tinh Hang Ngo Minh 《Journal of the World Aquaculture Society》2017,48(2):227-239
There is growing interest in sustainable intensification of aquaculture production. Yet little economic analysis has been done on farm‐level effects of the economic sustainability of production intensification. Data from 83 shrimp farms (43 in Vietnam and 40 in Thailand) were used to identify (through principal component and cluster analyses) 13 clusters of management practices that reflected various scales of production intensity that ranged from 0–1999 kg/ha/crop to 10,000 kg/ha/crop and above, for both Penaeus monodon and Litopenaeus vannamei in Vietnam and Thailand. The clusters identified reflected sets of management practices that resulted in differing yields despite similarities in stocking densities among some clusters. The enterprise budget analysis developed showed that the more intensively managed clusters outperformed the less intensively managed clusters in economic terms. More intensively managed farm clusters had lower costs per metric ton of shrimp produced and were more profitable. The greater yields of shrimp produced per hectare of land and water resources in more intensively managed shrimp farms spread annual fixed costs across a greater volume of shrimp produced and reduced the cost per metric ton of shrimp. Costs per metric ton of shrimp produced decreased from the lowest to the highest intensity level (from US$10,245 at lowest intensity to US$3484 at highest for P. monodon and from US$24,301 to US$5387 for L. vannamei in Vietnam and from US$8184 at the lowest intensity level to US$3817 at the highest intensity level per metric ton for L. vannamei in Thailand). Costs of pond amendments used in shrimp production were particularly high in Vietnam and largely unwarranted, whereas fixed costs associated with the value of land, production facilities, equipment, and labor were sufficiently high in Thailand so that net returns were negative in the long run. Nevertheless, economic losses in Thailand were less at greater levels of intensification. The study demonstrated a clear value proposition for shrimp farmers to use natural resources (such as land) and other inputs in an efficient manner and supports findings from corresponding research on farm‐level natural resource use efficiency. Additional research that incorporates economic analysis into on‐farm studies of sustainable intensification of aquaculture is needed to provide ongoing guidance related to sustainable management practices for aquaculture. 相似文献
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青虾池塘养殖试验报告 总被引:2,自引:0,他引:2
利用边坡较缓、淤泥较浅的2个池塘(共计3.3亩),通过人工设置水花生和网片附着物、投喂全价配合饲料、保持中度肥水等水质调节和病害防治措施,进行青虾养殖试验,结果亩产量 115.5 kg,亩利税 1709元,投入产出比 1:2.88。指出池水透明度应保持 30~40cm。 相似文献
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Using Experimental Microcosms in Shrimp Research: The Growth-Enhancing Effect of Shrimp Pond Water 总被引:2,自引:0,他引:2
After preliminary six week experiments showed that shrimp pond effluent from an intensive culture growout pond had the capacity to nearly double shrimp growth in laboratory tanks, an 18 day experiment was designed to determine if similar results occurred in the presence of high quality feeds. The results presented here corroborate the hypothesis that autochthonous factors in shrimp pond water stimulate shrimp growth. These results revealed that performance of currently available shrimp feeds is greatly improved in the presence of pond effluent, regardless of feed quality. Increased feed performance did not appear to be an artifact of supplemental feed availability in pond effluent. The implications from these experiments are that, even in intensive culture systems (above 40 shrimp per m2 ), in-situ sources of nutrition play an important role in shrimp growth. 相似文献
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Development of shrimp aquaculture has been associated with increases in infectious diseases and environmental degradation. An effective alternative to chemicals and antibiotics used for the prevention of these problems is to administer probiotics into the rearing system. Three bacterial genera, Bacillus, Vibrio, and Pseudomonas, are commonly administered as probiotics in shrimp aquaculture. Candidate probiotics are species specific and need to be tested for their effectiveness for certain species in in vitro and in vivo. Supplementation into feed is more effective in conveying probiotics into animals compared to direct application into rearing systems. Overdosage or prolonged administration of probiotics can induce immunosuppression. A cell-density of 105 colony-forming units (CFU) per ml is widely recommended. A combination of probiotics results in better outcomes for the host than individual probiotics. Probiotics improve water quality while reducing pathogenic bacteria. Probiotics show positive effects through an improvement in the physiological and immune responses of shrimps. Probiotics are increasingly becoming important and more common in any organic shrimp farming. 相似文献
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The scope-for-growth (SFG) of an animal is the portion of assimilated energy used for secondary production after maintenance requirements are met. The SFG of Penaeus setiferus was calculated as the difference between absorption (A), and the sum of the respiration (R) and excretion (U) [SFG = A - (R+U)]. Protocols were developed and SFG determinations were replicated 18 times for shrimp maintained on an experimental feed (diet 1), and 18 times for shrimp maintained on a commercial feed (diet II). Somatic growth of the shrimp was determined by direct weight measurements and by conversions of SFG results into wet weight and the two values were compared. Results yielded a SFG of 99.8 ± 16.03 J/g per d and 33.78 ± 7.64 J/g per d for diets I and II, respectively. Scope-for-growth estimates appear to be suitable for comparisons of effects of various culture conditions on shrimp. 相似文献
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池塘养殖水体净化技术 总被引:1,自引:0,他引:1
从池塘养殖水体污染现状入手,分别介绍了池塘养殖水体的净化原理与方法,重点分析了具有投资少、处理成本低、且不产生2次污染的生物净化技术,通过比较,认为生物净化技术在池塘养殖中有着更为广阔地应用和发展前景,是实现无公害养殖和内陆渔业可持续发展的可行之路。 相似文献
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通过测定凡纳滨对虾(Litopenaeus vannamei)生长性能和监测池塘水质变化,研究分段养殖模式在对虾养殖过程中的应用价值.养殖实验在6口池塘内(0.267 hm2/口)进行,首先在其中2口池塘内进行对虾的中间培育,养殖密度为300×104尾/hm2.经过36 d和48 d的中间培育后,将对虾先后转移到其他4口池塘内,养殖密度为60×104尾/hm2,分别记为T1和T2组.剩余的对虾继续养殖在中间培育池塘内,记为C组.结果显示,经过分段养殖的T1和T2组对虾,在分池养殖阶段7d内,生长速度均明显增加,其特定生长率(SGR)分别达到9.36 %/d和6.76 %/d;养殖期间,T1组具有最大的SGR (9.36 %/d)和饲料投喂量,然而其饲料系数(FCR) (1.053)高于T2组(0.822);经过分段养殖的对虾FCR均低于C组(1.082).在分池养殖阶段的大部分时间,T2组对虾的SGR高于T1组;C组NH4+-N、NO2-N和Chl-a浓度低于T1组和T2组,而颗粒物含量(TPM)和总磷(TP)高于T1组和T2组;T2组Chl-a含量明显高于T1组和C组.结果显示,经过48 d中间培育后,即对虾体重约为2 g时进行分池养殖仍可保证对虾在较长时间内保持较大的生长速度,对于饲料的节约具有重要意义.由于分池养殖阶段具有较多的饲料投喂,经过36 d中间培育后的对虾具有最大产量.分池养殖池塘内饲料投喂少于全期养殖,有利于养殖系统的稳定,然而单位时间内投喂量增加则会影响水质.分段养殖模式在提高分池养殖阶段对虾的生长速度和保持水质稳定方面具有重要的应用价值. 相似文献
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“养虾先养水”是业内人士都认同的观点 ,它说明了水色在对虾养殖生产中的重要性。在整个养殖过程中 ,要营造良好而稳定的水色是养虾技术的重点和难点。说起来容易 ,做起来难度很大。现针对对虾高产养殖生产中经常碰到一些有关水色调控的问题 ,提出一些处理方法 ,以供参考或共同探讨 :1 虾池水色的标准及作用水色是虾池水体理化因子的综合反映 ,它与水中浮游生物的种类和数量有密切关系。对虾养殖生产中通常以池水的颜色、透明度的大小和清爽度来衡量池水水色的好坏 ,良好的水色应是黄褐色、黄绿色 ,清爽而亮泽 ,硅藻和绿藻同时成为优势种… 相似文献
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几种对虾池塘放养模式的生态效益评价 总被引:3,自引:1,他引:2
从生态效益角度对我国对虾池塘的几种放养模式进行了评价,综合放养模式符合生态平衡、物种共生互利以及对物质多层次利用等生态学原理,较之于单品种放养模式具有较高的生态效益,在我国具有强大的生命力和广阔的发展前景。 相似文献
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海南省对虾(Penaeid Shrimp)养殖业存在问题与对策 总被引:1,自引:0,他引:1
海南省对虾养殖业面临着严重困扰,普遍反映对虾生长速度缓慢、病害较多、养殖周期偏长、个体规格偏小、价格过低、虾农亏损严重等,作者结合本省对虾养殖实际,对海南省对虾养殖业存在问题进行客观分析,作出切实的对策措施。 相似文献
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Accumulation of Chemical Elements in Texas Shrimp Pond Soils 总被引:2,自引:0,他引:2
Gad Ritvo Joe B. Dixon Addison L. Lawrence Tzachi M. Samocha William H. Neill Michael E Speed 《Journal of the World Aquaculture Society》1998,29(4):422-431
Abstract— This study evaluated changes in chemistry of shrimp pond soils over one production cycle. Several soil nutrients, pH, organic matter, and total soluble salts were analyzed in the upper 10 cm of pond-bottom soil on two Texas shrimp farms in two consecutive years. Soil concentrations of S, P, Ca, Mg, K, Na, Mn, and Zn increased from one year to the next, S increased by 400 ppm. Organic matter did not accumulate. The pH decreased in all pond soils, owing perhaps to the oxidation of organic matter and/or inorganic compounds. There was no statistical difference in shrimp yield between the two consecutive years. These results indicated that the accumulation of S and soluble salts derived from seawater and feed should be monitored and evaluated to prevent excessive chemical element loading of pond soil and discharge water. 相似文献
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普通虾池对虾无公害(Non-Pollution)健康养殖试验 总被引:1,自引:0,他引:1
为寻求无公害健康养殖的途径,我们进行了普通虾池无公害对虾健康养殖试验。经过114d的养殖,试验池塘收获成虾总产量27,505kg,平均单产8,595.31kg/hm^2;对比池塘收获成虾总产量12,157kg,平均单产7,598.13kg/hm^2;试验池塘总产值66.01万元,获利27.04万元,平均每亩池塘获利5,633元;试验池塘总产值26.75万元,获利7.1万元,平均每hm^2池塘获利44,370元。试验池塘与对比池塘相比,平均单位面积获利增长90.43%。试验池塘由于采用了无公害养殖技术,成品虾各项规定指标均符合食品卫生安全标准,达到无公害食品要求。 相似文献
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赣榆县1999年对虾(Penaeus chinensis)与杂色蛤(Ruditapes variegata)混养面积380 hm2,收获杂色蛤4 800 t,对虾125 t,取得了较好的经济效益和社会效益.本项生态农业技术模式适宜在硬泥或沙泥底质的虾塘泥滩推广,其技术要点如下: 相似文献