海水灌溉滨海盐渍土的水盐运动模拟研究   总被引：10，自引：0，他引：10  

赵耕毛  刘兆普  陈铭达  邓力群  吴家梅 《中国农业科学》2003,36(6):676-680

 模拟江苏大丰夏季降雨条件 ,采用原状土柱 ,对江苏滨海盐渍土进行海水灌溉试验。结果表明 ,夏季滨海盐渍土 0～ 4 0cm土层中盐分的运动和再分布非常活跃 ,而 4 0～ 12 0cm土层中盐分较稳定。未灌溉处理一般不会有盐峰形成 ,始终处于较稳定的脱盐状态 ,但遇持续性高温干燥天气 ,会有较小的盐峰形成。海水灌溉各处理灌溉后 ,如果在很长一段时间内无降水 ,则 0～ 5cm土层中可溶盐将明显积累 ,形成巨大盐峰 ;而 5～ 2 0cm和 2 0～ 4 0cm土层形成的盐峰较小 ;4 0cm以下的土层一般无盐峰形成。灌溉海水的浓度越高 ,且灌溉后持续干旱的时间越长 ,则积盐越严重。海水灌溉处理中 ,Na+ 交换了Ca2 + 、Mg2 + 后 ,很快被土壤胶体吸附 ,在土体中较稳定 ;相反 ,Ca2 + 、Mg2 + 则遭到严重淋失 ;Cl-是较为活跃的离子 ,随水分蒸发在土壤表层积聚 ,随降雨和灌溉海水向下层迁移 ;HCO3 -较稳定 ,除非有大强度的降雨 ,否则 ,一般不会淋失。因此 ,只要夏季选择适宜浓度的海水灌溉 ,土体中的盐分不会积累。  相似文献   

Why won’t they grow? – Inhibitory substances and mollusc hatcheries     

J. B. JONES 《Aquaculture International》2006,14(4):395-403

Molluscs are known to be seriously affected by trace amounts of environmental pollutants such as tributyltin at concentrations in seawater that are below the level of detection by all but the most sensitive chemical analytical techniques. This extreme sensitivity by molluscs has led to use of both adults and larvae as biomonitors for environmental pollution. Mollusc aquaculture has led to an increasing demand for commercial hatcheries to supply seed stock, including selected genetic lines of spat and juveniles. It is becoming apparent that many of the unexplained “crashes”, ill thrift or failures of larvae to metamorphose in such hatcheries are primarily due to their being compromised for a range of reasons including traces of inhibitory or toxic substances in the water supply. Because dead and dying larvae are ideal substrates for bacterial and ciliate growth, such invaders are often assumed to be the primary cause of the problem and this hinders finding a solution. In addition, many of the toxins which may be implicated in crashes are sporadic in occurrence and are both difficult to detect and hard to remove from the water supply. This paper provides evidence for these toxic effects and suggests ways of reducing the problems.  相似文献   

Seasonal variation in flesh quality, comparison between large and small Atlantic salmon (Salmo salar) transferred into seawater as 0+ or 1+ smolts     

Bjorn Roth  Sten Johan Sverre Johansen  Jorma Suontama  Anders Kiessling  Odd Leknes  Bjorn Guldberg  Sigurd Handeland 《Aquaculture (Amsterdam, Netherlands)》2005,250(3-4):830-840

The aim of this study was to identify the effect of growth, size and season on the flesh quality of Atlantic salmon (Salmo salar). Following smoltification, two groups of size sorted 0+ and 1+ smolts (four treatment groups in all) were measured for body weight and length in January, June and October 2002. The fish were stored on ice for 4 days before filleted and samples taken for flesh colour, fat/dry content, end pH, gaping score and texture shear force. Large fish upon smoltification grew faster during the first year at sea, while smaller fish grew faster during the second year at sea, resulting in similar weight at slaughter. Season showed the main influence on quality, where fish slaughtered in October had harder texture, higher fat content and redder colour compared to previous samples (P < 0.05). There were only minor differences between the fish slaughtered in January and June (P > 0.15). No significant differences (P > 0.05) were detected as an effect of size or smoltification age when effects of season were accounted for in the statistical model. We conclude that the observed variation in quality was an effect of changes in growth with season. We recommend that actions aimed to halter growth prior to slaughter could be an effective control measure to reduce seasonal quality variations.  相似文献   

乳山湾海水,底质及贝类体内砷的研究   总被引：6，自引：0，他引：6  

辛福言  马绍赛 《海洋水产研究》1997,18(2):55-60

通过１９９５年６－９月对乳山湾的综合调查，初步摸清了乳山湾海水，底质及贝类体内砷的分布。该水域内砷的浓度范围为０．７２－６．８０μｇ／Ｌ，其平均值为１．９４μｇ／Ｌ；底质中砷的含量范围为５．０－９．６ｍｇ／ｋｇ，平均值为７．７７ｍｇ／ｋｇ；  相似文献   

河北省海域贝类养殖区生态环境质量评价研究   总被引：3，自引：1，他引：2  

崔力拓 《安徽农业科学》2011,(10):6004-6006,6010

[目的]加强贝类养殖环境的保护,保障水产食品的卫生安全。[方法]根据2009年10月同步进行河北省海域贝类养殖区海水、沉积物和养殖贝类质量的调查资料,采用海水质量评价指数、表层沉积物质量评价指数和养殖贝类质量评价指数以及贝类养殖生态环境质量综合评价对河北省海域贝类养殖生态环境质量进行了综合评价。[结果]海水质量、表层沉积物质量和养殖贝类质量水平平均为2级、5级和4级,总体分别处于较好、差和较差水平,贝类养殖区生态环境质量平均为3级,总体处于一般水平,其主要污染物为PO43-、DIN、大肠菌群,同时不同养殖区生态环境质量差异明显,其中浅海养殖区生态环境质量较好,为1类区,适合养殖贝类;潮间带养殖区生态环境质量较差,为3类区,不适合贝类养殖。[结论]除浅海养殖区外,河北省海域贝类养殖区生态环境亟待改良。  相似文献   

海水胁迫下马齿苋光合及抗氧化生理特性研究     

张边江  唐宁  华春  陈全战 《草地学报》2015,23(4):878-882

为筛选耐盐经济植物提供技术参考和理论依据,用不同浓度海水处理野生马齿苋(Portulaca oleracea)幼苗,测定了其叶绿素含量、气体交换和荧光动力参数及抗氧化生理指标。结果表明:在低浓度海水胁迫下马齿苋能保持较高的光合生产力和抗氧化特性,从而减轻盐胁迫对植株生长的伤害。  相似文献   

纳米材料净化海水育苗水体的实验研究     

杨菁  丁永良  胡伯成  宋红桥 《水产科技情报》2005,32(6):252-255

设计纳米功能滤料及涂料试验,应用于海水育苗水体的净化。通过对实验水体的温度、盐度、pH、溶氧、氧化还原电位、氨氮、亚硝酸盐氮、硝酸盐氮、菌落总数、水质线幅半高宽值测定,以及育苗（青蛤苗）成活率统计,对比纳米材料净化海水育苗水体的功效。结果表明：试验组降解有机物能力均优于对照组,并获良好抑菌效果;功能涂料、功能粉体试验组均能促进蛤苗增长,其成活率分别较对照组均值提高31．3％、9,1％：  相似文献   

Sublethal effects and safe levels of carbon dioxide in seawater for Atlantic salmon postsmolts (Salmo salar L.): ion regulation and growth     

Sveinung Fivelstad  Harald Haavik  Geir Lvik  Anne Berit Olsen 《Aquaculture (Amsterdam, Netherlands)》1998,160(3-4):305-316

Atlantic salmon (Salmo salar L.) postsmolts (0.17–0.26 kg) were exposed to four different levels of carbon dioxide partial pressure for 43 days in an open flow system: 0.6 mm Hg (control), 4.9 mm Hg (low), 12 mm Hg (medium), and 20 mm Hg (high). The water temperature was 15–16°C and the salinity 34‰. In the low carbon dioxide group (P_CO2=4.9 mm Hg; 10.6 mg/l), no significant differences were found in blood parameters (haematocrit, plasma chloride and plasma sodium) or in growth parameters (weight, length and condition factor) when compared to the control group. After 43 days, the mean plasma chloride concentration for the medium group (P_CO2=12 mm Hg; 26 mg/l) was significantly reduced, while weight and condition factor were slightly, although not significantly, lowered. For the high carbon dioxide group (P_CO2=20 mm Hg; 44 mg/l) plasma sodium and plasma pH were significantly increased and plasma chloride, oxygen consumption, weight, length and condition factor were significantly reduced at the end of exposure. There was no mortality in the control group or in the low carbon dioxide group. The mortalities in the medium and high carbon dioxide groups were 1.1 and 4.3%, respectively. Nephrocalsinosis was not observed in any of the groups. The results of the present investigation indicate that the CO₂ concentration of the low group may represent a safe level for Atlantic salmon postsmolts when the temperature is 15–16°C and the oxygen level is 6–7 mg/l. Further studies are required.  相似文献   

鱼虾蛏在海水池塘的混养试验     

林其章 《福建水产》2008,(2)

本文报道双斑东方鲍、日本对虾及缢蛏在一口面积为1.6ha的海水池中混养试验情况.经合理搭配、精心饲养,通过生物间的相互作用和人为调节,使养殖池形成一个稳定良好的生态系统,有效地抑制病虫害的发生,鱼、虾、蛏混养的成活率、生长速度、产量均较为理想,获得了显著的养殖效果.  相似文献   

海水入侵-地下水位变化-土壤盐渍化自动监测实验研究     

潘玉英  付腾飞  赵战坤  张颖  贾永刚 《土壤通报》2012,(3):571-576

利用国家863课题支持研制的电阻率探杆自动监测系统,分别进行了海水入侵、地下水位升降、土壤盐渍化过程的动态监测室内模拟实验,旨在探讨该系统用于海水入侵、地下水位变化、土壤盐渍化等环境过程自动监测的可行性。结果表明,海水入侵形成的咸-淡水界面及海水弥散带,地下水位位置上下及包气带,及不同含盐量的土体,均具有显著的电阻率探杆测试结果特征差异。该系统可为海水入侵,地下水位变化,土壤盐渍化,土壤地下污染等环境过程的原位连续实时自动监测提供数据资料及技术支持。  相似文献