Pre-and Post-Liming Aquatic Communities and Trout Diets

In the period following liming and before the introduction of brown trout to Loch Fleet, there was a reduction in the numbers of invertebrates, including the Chironomidae, Oligochaeta and Hydracarina in the loch, but an overall increase in invertebrates in the inlet and outlet streams. This was followed in the loch by a recovery in the numbers of certain groups (particularly the Trichoptera and Ephemeroptera) to pre-liming levels in spite of the introduction of the trout.

The diets of the trout comprised a wide variety of aquatic and terrestrial organisms ranging in size from Fprotozoans to newts and are dominated by chironomids. Opportunistic type of feeding as found in the present study appears to be typical of the brown trout and is reported for many water bodies by other workers.

Significant differences (P < 0.05 and P < 0.001) were found in the numbers and weights of certain food organisms in the stomachs of brown trout caught by different fishing methods in the summers of 1992 and 1993. Fish caught by gill net contained fewer planktonic crustaceans and chironomids, but greater numbers of trichopterans and terrestrial organisms, than in those caught by fly and spinner. the differences are probably related to differences in the depth at which the fish, caught by the various methods, were feeding.     

阴极材料对三相三维电极反应器电解处理酸性橙7的影响研究

采用具有不同阴极材料的三相三维电极反应器,对300 mg/L酸性橙7(AO7)模拟废水进行处理研究,重点考察阴极材料对脱色率和反应体系矿化能力的影响,同时利用HPLC、UV-Vis、GC-MS等分析方法对·OH、H2O2以及降解产物进行测定,探讨了3种电极对AO7的降解行为.结果表明,在电压20 V条件下电解60 min后,活性炭纤维(ACF)、石墨和不锈钢等3种阴极体系对于AO7的脱色率均高于96%,三者之间没有明显差别.但是ACF体系对TOC的去除率可达到57.4%,高于其它两者.3种阴极体系中均有高活性的·OH和H2O2生成,但是ACF阴极体系中产生的浓度较高,从而决定了其具有较高的矿化能力.几种不同电极体系电解AO7过程中都遵循了相同的产生酮类和萘酚类物质的过程.     

H-酸的催化湿式氧化反应过程研究

湿式氧化（ＷＡＯ）和催化湿式氧化（ＣＷＡＯ）都能有效地处理染料中间体－－Ｈ－酸。所有的Ｈ－酸在５ｍｉｎ内均被支除和形成一些中间产物。在不同反应时间段测定了ｐＨ值及阴、阳离子和小分子有机酸等中间产物。分析表明,ｐＨ值与ＣＯＤ的去除及有机酸的产生有密切的联系,Ｈ－酸被氧化成ＮＨ４＾＋、ＳＯ４＾２－、ＨＣＯＯＨ和ＣＨ２ＣＯＯＨ。ＷＡＯ法的瓜速率慢而且氧化乙酸困难。而ＣＷＡＯ法的反应速率不但快而且能有效地     

不同环境条件下偶氮染料酸性大红GR的生物降解性能

为了考察不同环境条件下偶氮染料酸性大红GR生物降解性能,采用已驯化的混合菌群作为接种液进行偶氮染料酸性大红GR脱色试验。结果表明,微氧条件下(静置敞口培养),偶氮染料酸性大红GR脱色效果最佳,染料脱色主要发生在菌体的对数生长期。混合菌群对pH、温度适应范围较广,pH为3.32~9.18,温度在20℃~37℃范围内均可以获得较好脱色效果,脱色率均在80%以上。微氧条件下酸性大红GR降解历程表明,偶氮基整个共轭系统被破坏,生成了一种新的结构,使原有的某些精细结构在二阶导数光谱中得以表现,由此探讨其生物降解机理。     

Phosphatase activity and culture conditions of the yeast Candida mycoderma sp. and analysis of organic phosphorus hydrolysis ability

Orthophosphate is an essential but limiting macronutrient for plant growth. About 67% cropland in China lacks sufficient phosphorus, especially that with red soil. Extensive soil phosphorus reserves exist in the form of organic phosphorus, which is unavailable for root uptake unless hydrolyzed by secretory acid phosphatases. Thus, many microorganisms with the ability to produce phosphatase have been exploited. In this work, the activity of an extracellular acid phosphatase and yeast biomass from Candida mycoderma was measured under different culture conditions, such as pH, temperature, and carbon source. A maximal phosphatase activity of 8.47 × 10^5±0.11× 10^5 U/g was achieved by C. Mycoderma in 36 hr under the optimal conditions. The extracellular acid phosphatase has high activity over a wide pH tolerance range from 2.5 to S.0 （optimum pH 3.5）. The effects of different phosphorus compounds on the acid phosphatase production were also studied. The presence of phytin, lecithin or calcium phosphate reduced the phosphatase activity and biomass yield significantly. In addition, the pH of the culture medium was reduced significantly by lecithin. The efficiency of the strain in releasing orthophosphate from organic phosphorus was studied in red soil （used in planting trees） and rice soil （originating as red soil）. The available phosphorus content was increased by 230% after inoculating 20 days in rice soil and decreased by 50% after inoculating 10 days in red soil. This work indicates that the yeast strain C. mycoderma has potential application for enhancing phosphorus utilization in plants that grow in rice soil.     

酒石酸淋洗过程中土壤重金属解吸动力学特征

采用批处理淋洗的方法,研究了酒石酸淋洗修复张士污灌区土壤过程中镉、铅、铜、锌4种重金属离子解吸动力学特征。结果表明,酒石酸在12h条件下,达到对污染土壤中镉离子的最大去除率,铅、铜、锌3种重金属离子达到最大去除率则需要24h。4种重金属离子的解吸动力学过程可以用Elovich方程很好的描述,说明酒石酸去除重金属离子的过程是一种非均相扩散过程。此外,解吸速率曲线显示,反应初期相同时刻上酒石酸对铅离子的解吸速率最快,其次是铜和锌,最后是镉离子;反应后期同一时刻上铜和锌的解吸速率大于铅和镉。     

Fenton试剂处理酸性玫瑰红B的研究

采用Fenton试剂处理酸性玫瑰红B染料废水,考察了FeSO4投加量、H2O2投加量、pH值和反应时间对处理效果的影响,研究了原水的氧化还原电位和TOC的变化规律,评价了它的可生化性。结果表明,最佳pH值为3,FeSO4的适宜投加量为8mmol/L,H2O2最佳投加量为50mmol/L,此时COD去除率和脱色率分别为77.1%和92.8%,处理后该染料废水的可生化性大大提高。     

海洋气溶胶对沿海地区降水组成的贡献

以青岛地区为对象，对沿海地区大气气溶海洋因子对降水组成的贡献，进行了研究分析。结果表明，１）夏季受海洋影响要比冬季明显得多；（２）降水中主要的碱性物质，不论是夏季或冬季，９９％来自大陆气溶胶，海洋的影响可忽略；（３）海洋影响的程度和离海边的距离有关，离海愈远，受海洋影响就愈小，离海愈近，受其影响就愈大。     

酸沉降物对土壤化学性质的影响

本文综述了酸沉降物对土壤酸化、营养物质的淋溶、重金属的活化、矿物分解等化学性质的影响，以及阻止酸雨危害土壤的化学方法。     

BP神经网络在降水酸度预测中的应用

本文利用南昌市城市大气中SO2、NOX、TSP等浓度数据及降尘数据建立了BP神经网络的降雨酸度预测模型，结果表明：BP神经网络的预测模型不仅能较好地反映致酸因素与降水酸度的相互关系，而且预测精度也高于多元回归等模型。