菌株Bacillus sp.CLb芽孢漆酶对染料、模拟染料废水脱色的研究

[目的]研究芽孢杆菌菌株CLb的芽孢漆酶在介体的互作下对不同类型的染料及模拟染料废水的脱色效果。[方法]制备芽孢粗酶液,在介体的互作下,测定具有漆酶活性的粗酶液对活性亮蓝、活性黑、靛红和结晶紫的脱色效果,筛选出对染料脱色有促进作用的漆酶介体,并且研究芽孢漆酶在不同pH条件下对染料和模拟染料废水脱色的影响。[结果]菌株CLb的芽孢漆酶在无介体参与下只能使活性亮蓝和结晶紫脱色。在介体乙酰丁香酮（ACE）的作用下,芽孢漆酶对4种染料的脱色率均超过70%。在pH 7.0条件下,芽孢漆酶浓度为44.74 U/L和介体ACE浓度为1 mmol/L时对模拟染料废水的脱色效果最好,6 h脱色率超过80%。在介体乙酰丁香酮存在,pH 7.0的条件下,菌株CLb的芽孢漆酶对合成染料脱色效率高于pH 9.0时的脱色率。[结论]在介体乙酰丁香酮的存在下,芽孢漆酶对染料和模拟染料废水均具有较好的脱色效果。     

Nitrous oxide emissions from dairy farm effluent applied to a New Zealand pasture soil

A field experiment on permanent ryegrass–white clover pasture at AgResearch's Ruakura dairy farm near Hamilton, New Zealand quantified nitrous oxide (N₂O) emissions from different types of dairy effluent applied to soil at three seasons and evaluated the potential of dicyandiamide (DCD) (a nitrification inhibitor) to decrease gaseous N₂O emissions. Fresh or stored manure and farm dairy effluent (FDE; from dairy shed washings), with or without DCD (10 kg/ha), were applied at approximately 100 kg N/ha to plots on a well‐drained soil on volcanic parent material. A field chamber technique was used to measure N₂O emissions. Application of manure or FDE, both in fresh and stored forms, to pasture generally increased N₂O emissions. Overall N₂O emission factors (EF) varied between 0.01% and 1.87%, depending on application season and effluent type. EFs in spring and autumn were greater than those in summer (P < 0.05). Among the effluents, N₂O EFs were largest from fresh FDE (1.65%) during the spring measurement period, stored manure (1.87%) during the autumn and stored FDE (0.25%) during the summer. DCD was effective in decreasing N₂O EFs from fresh FDE, fresh manure, stored FDE and stored manure by 40–80%, 69–76%, 24–84% and 60–70%, respectively. DCD reduced N₂O emissions during the spring and autumn seasons more effectively than in the summer season.     

Monitoring shrimp growth with control charts in aquaculture

This work proposes a method for the statistical monitoring of the weekly weight of shrimp in a fish farm. The design of control charts for shrimp growth presents several challenges, the main ones being the presence of trend and autocorrelation. Several control charts are proposed, the most efficient being a chart based on the residuals of a second order autoregression whose parameters vary with the week. A control chart with less computational complexity is also provided. It is simply based on growth rates and works well at detecting negative weight changes. Real data from a large shrimp farm has been used for both the design and the evaluation.     

高氨氮厌氧消化液后处理技术研究

采用SBR-絮凝沉淀-Fenton氧化-活性炭吸附组合工艺对高氨氮厌氧消化液的后处理进行实验研究.结果表明,当进水COD浓度为4516 mg·L^-1时,SBR出水COD可降为1752 mg·L^-1,去除率达到61.2%;絮凝沉淀出水COD浓度为1189 mg·L^-1,去除率为32.1%;Fenton氧化和活性炭吸附出水COD浓度分别为452和216 mg·L^-1,去除率分别为61.7%和52.7%.当进水NH3-N浓度2162 mg·L^-1时,SBR出水NH3-N浓度降至13.8 mg·L^-1,去除率为99.4%,NH3-N主要在该段去除.整个组合工艺对COD和NH3-N的去除率分别达到95.2%和99.9%,达到了很好的有机物和氨氮去除效果,在技术上是可行的.     

碱法草浆造纸蒸煮黑液厌氧生物降解及其主要微生物类群研究

采用中温(35±1℃)UASB AF相结合的反应器处理碱法草浆造纸蒸煮黑液,设计了两种试验方案。试验方案Ⅰ-碱法草浆黑液酸化后进行厌氧发酵,Ⅰ号反应器内装陶粒。试验方案Ⅱ-黑液用化学法(HCl)去除木质素后进行厌氧发酵,Ⅱ号反应器内装软填料。进行HRT、有机负荷和有机污染物(COD_(cr)、BOD_5)去除效率、沼气产气率相关性试验。在厌氧发酵稳态运行条件下,采用Hungate厌氧操作技术,MPN计数法对UASB AF反应器内厌氧污泥中的主要微生物类群区系组成进行了生态分析研究。     

虾塘水体中浮游植物群落特征及其与营养状况的关系

通过对虾养殖期间的连续监测结果;讨论和阐述了虾塘水体中浮游植物群落特征及其与营养状况的关系。虾塘中浮游植物在生态学上主要表现为群落构成简单、优势种单一且演替速度快,从而决定了该环境中浮游植物群落的不稳定性。无机氮营养盐（IN）是浮游植物繁殖生长的限制性因素,二者之间里较好的幂函数衰减曲线关系（R＝0．76）,且当浮游植物密度降至3．2×103细胞／ml时,水环境中的IN呈跃升趋势,此时所对应的透明度为0．6±0．2m。     

显微注射生长激素基因导入中国对虾（Penaeus chinensis）受精卵的研究

本实验采用显微微量注射方法，交羊生长激素基因导入中轻地虾受精卵，受精卵发育到蚤状幼体第三期后采样检测。ＰＣＲ检测结果表明：７个样品共９３尾幼体，有３个样品呈出阳性信号，基因转移比率至少在３％以上。同时斑点杂交结果也证明有两个明显阳性斑点。     

对虾养殖中新生残饵耗氧动态及其规律的研究

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。     

对虾养殖生态环境的研究现状和展望

依据近几年的有关参考文献对有关对虾生态环境的研究成果及存在的问题进行了评述。从生态学方面阐述了对虾养殖生态系统的特点,提出对虾养殖生态环境中理化因子的研究应该更注意与生物及微生物因子的结合。     

Effects of shrimp pond water on phytoplankton: importance of salinity and trophic status of the receiving environment

Aquaculture generates a large load of effluents rich in organic matter and nutrients that may be introduced into the environment. This study aimed to assess in a microcosm experiment, the effect of shrimp pond water mixed with Patos Lagoon estuary water on phytoplankton chlorophyll a and primary production, simulating two salinities. Chlorophyll a, dissolved inorganic nutrients and primary production were measured in two experiments. In Harvest I, salinity of shrimp pond and environment water was similar, and chlorophyll a showed different trends over time, according to the amount of nitrogen available. In Harvest II, with different salinities and high nutrient concentrations in environment water, chlorophyll a levels showed a similar increasing trend over time in all mixtures. Net primary production showed differences among treatments in the first sampling in Harvest I, but not in the second, whereas no differences were observed among treatments in Harvest II. We conclude that shrimp pond effluent can lead to short‐term variations in chlorophyll a and primary production levels, with similar salinities. Salinity differences result in lower chlorophyll a and primary production values than expected according to the nutrient input. Differences in salinity can be an important management strategy to choose the best harvest period.