藻类活性细胞生物肥在水稻上的应用

为验证藻类活性细胞生物肥在水稻上的应用效果,笔者在水稻上开展了应用试验,试验设空白对照、常规施肥、藻类活性细胞生物肥及2个藻类活性细胞生物肥+减少化肥用量10%、20%等5个处理,3次重复。结果表明：应用藻类活性细胞生物肥,能促进水稻分蘖,提高成穗率,增加有效穗,提高结实率,增加实粒数,同时增加千粒重,提高水稻产量,并能提高化肥利用率;尤其在减少化肥用量10%~20%的情况下,仍能促进水稻生长,提高水稻产量。施用藻类活性细胞生物肥,水稻产量增长1.1%~6.32%,收入增加-33~1206元/hm²。     

A simple substrate to produce the tropical epiphytic algae Hypnea pseudomusciformis

The seaweeds Hypnea spp have been used as a direct human food, for carrageenan extraction, and exploitation of chemical compounds of interest. Nevertheless, its culture is still undeveloped because of difficulties in managing the epiphytic habit. Therefore, this study focuses on obtaining a suitable substrate for Hypnea pseudomusciformis settling and developing associated to a simple and efficient system to produce this red alga in tropical coastal regions of South Atlantic. We developed a substrate comprised of a 1 cm diameter polypropylene cable with 60 cm length, which was totally shredded. This structure allows that the epiphytic algae grow settled on the substrates and not only appended to it. A modular long-line structure comprised of 1 m polypropylene braided cables with two substrates spaced 30 cm each. Testing the prototype in a seaweed small-farm resulted in a growth rate of 5.66 % day⁻¹ and a productivity of 0.64 kg m⁻¹ in 45 days. This simple patented technology may base used the development of the culture of H. pseudomusciformis in familiar or industrial scales.     

The effect of microorganisms,salinity and turbidity on hydraulic conductivity of irrigation channel soil

The introduction of polysaccharide producing benthic algae and bacteria could provide a low cost technique for seepage control in irrigation channels. The ability of algae and bacteria to produce polysaccharides proved to be successful in reducing the hydraulic conductivity of irrigation channel soil. Hydraulic conductivity was reduced to less than 22% of its original value within a month of inoculating soil columns with algae. Chlorophyll and polysaccharide concentrations in irrigation channel soil were measured in order to assess the growth of algae and extent of polysaccharide production, and their correlation with hydraulic conductivity of channel soil. Increases in polysaccharide occurred in the top layer (0–5 mm) of the soil column. The reduction of hydraulic conductivity was highly correlated with the amount of polysaccharides produced (r ² = 0.92). Hydraulic conductivity decreased with increasing algal and bacterial numbers. The first few millimetres of the soil core where microbial activity was concentrated, seemed effective in controlling seepage. Incorporation of extra nitrate and phosphate into algal medium did not increase the production of polysaccharides by algae in channel soil. The effect of salinity and turbidity of irrigation channel water on channel seepage was studied by measuring the effects on hydraulic conductivity of channel soils. When the electrical conductivity (EC) of the water increased above a threshold value, the hydraulic conductivity increased because of the flocculating effects on clay particles in channel soils. A relationship between sodium adsorption ratio (SAR) and EC of the channel water was established which indicated 15% increase in channel seepage due to increases in salinity. Increasing the turbidity of irrigation water (by increasing the concentration of dispersed clay) resulted in lowering the hydraulic conductivity of the channel soil due to the sealing of soil pores by dispersed clay particles. When the turbidity of the water was 10 g clay l^–1, the hydraulic conductivity was reduced by 100%. An increase in clay concentration above 1 g l^–1 resulted in significant reduction in hydraulic conductivity. Soil bowl experiments indicated that clay sealing with a coating of hydrophobic polymer on the surface could also effectively prevent seepage of saline water.     

海藻肥对大棚洋香瓜产量和品质的影响

以南非生产的海藻肥和洋香瓜伊丽莎白为材料,研究了膨瓜期喷施海藻肥对大棚洋香瓜产量和品质的影响。结果表明,在膨瓜期喷施250倍海藻肥的效果最佳,可使洋香瓜伊丽莎白提早采收3天、增产4.03%;洋香瓜外观颜色加深、着色均匀、果肉厚度和含糖量增加、可溶性固形物和VC的含量提高。     

河沙表面改性絮凝去除水华铜绿微囊藻的研究

[目的]研究十六烷基三甲基溴化铵(CTAB)、双烷基聚氧乙烯基三季铵盐(DPQAC)和聚二甲基二烯丙基氯化铵(PDMDAAC)3种季铵盐阳离子表面活性剂改性河沙对去除铜绿微囊藻的影响.[方法]通过系统研究S-CTAB样品的粒径、制备温度、老化时间、pH、投加量对除藻率的影响,并且通过对S-CTAB样品絮凝沉降速率的研究,探讨了河沙表面改性的除藻机理.[结果]相同条件制备的S-CTAB对铜绿微囊藻的去除效果高于S-DPQAC和S-PDMDAAC.CTAB与河沙的质量比为0.04 g/g、河沙粒径为200目、投加量为5 g/L、水浴温度为40℃制备的S-CTAB样品表现出对铜绿微囊藻最佳的去除效果.S-CTAB样品对铜绿微囊藻的去除机理可能原因是通过改性河沙对藻类的架桥网捕作用及河沙表面季铵盐离子对藻细胞的灭杀作用.[结论]该研究提出的河沙表面改性除藻技术具有良好的效果,为河沙表面改性去除水华藻提供了一定的理论基础.     

稻鸭共生对稻田水生生物群落的影响

通过稻田共生的田间试验，对稻鸭共生稻田水体中的藻类植物和水生动物的种类、数量及生物量进行测定分析。结果表明：在水生生物种类组成上看，稻田水体中藻类植物共39属，水生动物共33属，都以对照为最高。藻类植物在数量上以对照为最高，为6.075×106ind/L，显著高于放鸭小区，在生物量上以放4只鸭为最高，但差异不显著。不同藻类构成比较分析，在数量上以硅藻、蓝藻和绿藻占优势，分别占个体总数的33.96%、29.45%和23.58%，在生物量以蓝藻和裸藻占优势，它们分别占总生物量的48.23%和26.72%，养鸭后绿藻的优势度下降，裸藻、蓝藻优势度上升。各类水生动物的数目和生物量均按水源区、对照区、少鸭区、多鸭区的顺序下降，但差异不显著。其数量上以原生动物优势，而生物量上以蚌虫占优势。在多样性方面，藻类植物以水源区和放4只鸭为最高，香农多样性指数都为2.03，水生动物多样性指数以放6只鸭为最高，香农多样性指数为1.765。可见，稻鸭共生增强了稻田生态系统的自然属性。     

啤酒废水培养螺旋藻的研究

[目的]研究啤酒废水培养螺旋藻的可行性。[方法]利用啤酒废水培养螺旋藻,研究不同废水浓度下螺旋藻的生长状况及其对废水中氮、磷、有机质的去除效率,以及在放大培养时螺旋藻的生物量、蛋白质和脂肪舍量。[结果]螺旋藻可在啤酒废水中生存,且啤酒废水有缓冲培养液pH增加的作用,能使螺旋藻更长时间处于适宜生存的状态。50％啤酒废水、50％Zarrouk培养液最适宜螺旋藻生长,且产量达到最大。同时,螺旋藻可对啤酒废水产生净化作用。螺旋藻对100％啤酒废水中有机质、总氮、总磷的去除效率分别可迭55．95％、77．78％和42．62％。在最佳配比浓度条件下,放大培养的产藻量为0．794g/L,蛋白质和脂肪含量分别达到69．5％和8．11％。[结论]该研究可使污水净化和螺旋藻利用相结合,达到环境与经济效益的统一。     

木薯新发藻斑病在中国的发生调查及病原鉴定

2010~2015年,笔者在对中国木薯主栽区的病害调查中发现了一种新的叶斑病。该病在云南、海南、广西、江西、福建等地区均有发生,生长中后期爆发流行,初步分析低温是该病成灾的关键因子。病原在叶片上形成黄褐色或黑褐色、近圆形、中央灰白色毛毡状的病斑,发病叶片大量脱落,严重影响木薯的长势和产量。对来自不同地区的病样进行显微观察。结果表明:病原在寄主组织上均形成有隔的孢囊梗,单生或丛生,其上着生数个圆形、黄色的孢子囊,表明其为寄生性头孢藻。     

水动力循环复氧控藻技术在城市景观水体富营养化治理中的应用研究

在无锡蠡溪公园西苑水体中采用了水动力循环复氧控藻(HAAC)技术,研究了该技术对城市景观水体富营养化的处理效果。结果显示:在实施水动力循环复氧控藻(HAAC)技术的8个月期间,CODMn、TN、NH4+-N和TP平均去除率分别达到28.0%、35.7%、49.7%和37.0%;藻类叶绿素a平均去除率达40.2%,藻类总丰度平均下降率达56.0%,藻类群落从单一结构转变为多种优势种共存的结构。水华现象得到了有效控制,水体生态环境明显转好,处理期结束时西苑水体已达到IV类水标准。研究表明,水动力循环复氧控藻技术作为一种新型的水生态修复技术在城市景观水体富营养化治理工程中起到了很好的效果,值得推广应用。     

藻类DNA条形码技术在藻类研究中的应用

DNA条形码技术是用一个短的DNA片段对物种进行快速的鉴定和识别.以往的研究主要选取线粒体、质体和核糖体的部分片段来进行分析,但藻的种类不同,DNA片段不同,结果也不同.文中主要介绍了藻类DAN条形码的研究状况,并总结了用于藻类DNAbarcoding研究的基因片段的特点及所存在的问题,为藻类DNA条形码的进一步深入研究提供参考.