Ecological and Industrial Implications of Dynamic Seaweed-Associated Microbiota Interactions

Seaweeds are broadly distributed and represent an important source of secondary metabolites (e.g., halogenated compounds, polyphenols) eliciting various pharmacological activities and playing a relevant ecological role in the anti-epibiosis. Importantly, host (as known as basibiont such as algae)–microbe (as known as epibiont such as bacteria) interaction (as known as halobiont) is a driving force for coevolution in the marine environment. Nevertheless, halobionts may be fundamental (harmless) or detrimental (harmful) to the functioning of the host. In addition to biotic factors, abiotic factors (e.g., pH, salinity, temperature, nutrients) regulate halobionts. Spatiotemporal and functional exploration of such dynamic interactions appear crucial. Indeed, environmental stress in a constantly changing ocean may disturb complex mutualistic relations, through mechanisms involving host chemical defense strategies (e.g., secretion of secondary metabolites and antifouling chemicals by quorum sensing). It is worth mentioning that many of bioactive compounds, such as terpenoids, previously attributed to macroalgae are in fact produced or metabolized by their associated microorganisms (e.g., bacteria, fungi, viruses, parasites). Eventually, recent metagenomics analyses suggest that microbes may have acquired seaweed associated genes because of increased seaweed in diets. This article retrospectively reviews pertinent studies on the spatiotemporal and functional seaweed-associated microbiota interactions which can lead to the production of bioactive compounds with high antifouling, theranostic, and biotechnological potential.     

皱纹盘鲍与光棘球海胆筏式混养研究

皱纹盘鲍与光棘球海胆的混养可有效地防治污损生物的附着。综合分析鲍与海胆的生长、存活及防污损生物附着的效果，在生长期、高温期和恢复生长期混养海胆的最适密度分别为１５．２０个／格和１５－２０个／格。     

珠江口竹洲人工鱼礁与相邻天然礁附着生物群落结构研究

2011年9月利用潜水原位采样法对竹洲人工鱼礁及附近天然岛礁上附着生物群落进行了调查。此次调查共记录附着生物68种,多属于热带一亚热带暖水种,其中优势种为网纹藤壶（Balanusreticulatus）、华美盘管虫（Hydroideselegans）和马氏珠母贝（Pinctadamartensi）。投礁6个月的礁体上附着生物种类和生物量与天然岛礁上附着生物存在显著差异,投礁12个月礁体上附着生物种类与天然岛礁上附着生物差异有减少趋势,生物量不存在显著差异。聚类分析表明竹洲礁区海域附着生物群落可划分为2个群落,投礁12个月礁体与天然岛礁同属一个群落,投礁6个月礁体附着生物为一个群落。人工鱼礁附着生物群落演替过程中改变了礁体表面空间结构,空间异质性提高,人工鱼礁附着生物群落逐步向着天然岛礁附着生物群落的方向发展。     

Efficacy of Netminder® silicone release coating for biofouling reduction in bay scallop grow‐out and comparative effects on scallop survival,growth and reproduction

Netminder^®, a water‐based silicone barrier release coating, was highly effective in reducing biofouling of lantern nets during grow‐out/overwintering of bay scallops, Argopecten irradians irradians, in a large‐scale restoration programme in New York, USA. Compared with untreated nets, scallops held in Netminder^®‐coated nets experienced reduced survival after 8 months, probably due to higher loads of epibionts on their shells. However, this was countered by higher reproductive and overall condition of scallops in treated vs. untreated nets; there were no consistent differences in shell growth in different net treatments. Although further testing is recommended under a wider range of conditions, we conclude that for the purposes of our scallop restoration work, coating nets with Netminder^® would eliminate the need for a gear change in spring, thus reducing labour costs; the coating process should be refined so that Velcro closures of nets do not become sealed shut.     

一体式膜生物反应器处理水产养殖废水膜污染特性研究

采用一体式膜生物反应器（ MBR）处理水产养殖废水,对处理过程中MBR膜污染的特征进行研究。首先,选取污泥浓度（ MLSS）、水力停留时间（ HRT）和曝气量这3个与膜污染有密切关系的变量,通过组合优化,研究操作条件对膜污染的影响,并确定最佳操作条件;其次,在最优化参数组合情况下,通过长期稳定运行,确定膜压增长特点;最后,通过膜阻力分布分析,得出造成膜污染的最主要原因。结果显示,对膜污染的贡献依次为：曝气量＞HRT＞MLSS;最佳的操作参数组合为曝气量437．5 L/h,HRT 4．25 h,MLSS 2．2 g/L;长期稳定运行过程中,发现膜压增长呈现出快速增长、平稳增长、急剧增长的3个阶段;通过膜阻力分布分析,得出由胞外聚合物（EPS）和微生物代谢产物（SMP）形成的吸附性膜孔阻塞是造成膜污染的最主要原因。因此,优化操作条件和减少混合液中EPS和SMP是减轻膜污染的重要手段。     

皱纹盘鲍与光棘球海胆越冬期筏式混养的初步研究

实验分越冬前期和越冬后期两个阶段进行。越冬前期鲍与海胆在生长方面的结果无显著差异,但混养可防止苔藓虫的附着,海胆的混养效果以２０个／格略好;越冬后期海胆混养的密度则以５个－１０个／格为最佳,混养可有效地防止多种敌害生物附着。     

东海水产养殖区七种海鞘优势种相关活性物质研究进展与利用前景

海鞘是主要海洋污损生物之一,对海洋生物多样性、海水养殖和生态环境都有不利影响。本文简述了中国东海几个主要水产养殖区7种海鞘优势种生物量、相关的次生代谢产物及其生物活性的研究进展,并对其利用前景进行了展望,为进一步研究开发提供依据。     

水流近壁面水力剪切力对滴灌系统碳酸钙污垢的影响

针对目前水动力学条件对滴灌系统碳酸钙污垢形成的影响及适宜的污垢控制阈值尚不明确的问题,该研究对不同近壁面水力剪切力(0～0.70 Pa)下的滴灌系统附着碳酸钙污垢总量、晶相组成及表观形貌进行了分析。结果表明：不同剪切力显著(P<0.05)影响了碳酸钙污垢的形成,随着剪切力的增大碳酸钙污垢的总量呈现先增高后降低的趋势,最大碳酸钙污垢形成量的剪切力为(0.42±0.02)Pa。剪切力较低(0～0.42 Pa)时,随着剪切力的增大碳酸钙晶体的尺寸逐渐变大,Ca²⁺和CO₃^2-的碰撞几率增加且晶体成核效率提高,使得碳酸钙污垢总量呈现增加趋势;剪切力较高(0.42～0.70 Pa)时,随着剪切力的增大碳酸钙晶体大小逐渐减小,且晶体由于高剪切力的作用发生破碎和脱落,使得碳酸钙污垢总量呈现下降趋势。建议灌水器流道近壁面水力剪切力控制在0～0.24 Pa和0.65～0.70 Pa,以减少碳酸钙污垢的形成。该研究结果可为高抗堵塞灌水器的研发以及劣质水滴灌技术的应用和推广提供支撑。     

改性填料强化组合MBR处理印染废水的效果研究

以改性填料作为填料组成的膜生物反应器处理某印染废水,考察了系统对污染物去除效果及减缓膜污染方面的作用。结果表明,反应器对COD和NH3-N均有着较高的去除效果,当进出水COD浓度分别为436～1 722 mg/L、43～79 mg/L,进出水NH3-N浓度分别为160～245 mg/L、6.6～16.8 mg/L时,COD、NH3-N的去除率分别为88.99%～96.93%9、0.69%～95.94%。其出水水质达到《城镇污水处理厂污染物排放标准》(GB18918-2002)二级标准。抽吸时间20 min时的膜过滤阻力上升较快,而抽吸时间15 min能较好地维持膜通量,保持膜过滤性能的稳定。在膜通量为11.2 L/(m2.h)情况下,透膜压差随运行时间的递增而呈现缓慢上升的趋势,改性填料对减轻膜污染的贡献明显;ρ(MLVSS)/ρ(MLSS)比值与SOUR的变化趋势基本保持一致,该系统内生物膜含有较高的挥发性有机成分,具有较高的活性。改性填料的投加有效地减轻了膜污染,大大延长了膜清洗的工作周期。     

MBR膜污染形成机理及控制膜污染研究进展

膜生物反应器(MBR)与传统活性污泥法相比,具有出水水质好、占地面积小等一系列优点,但膜污染问题却成为限制MBR发展的关键因素之一。介绍了膜污染的形成机理,并综述了控制膜污染方式的研究进展,为有效解决MBR膜污染问题提供了参考。