巢湖水体细菌群落结构及多样性研究

研究巢湖水体细菌群落结构和多样性,为生态修复提供理论依据。在南淝河入湖口、兆河入湖口和裕溪河出湖口3个采样点采集水样,应用高通量测序技术对水体细菌的16S rRNA基因进行序列测定,应用Qiime软件调用UCLUST程序将所获得的优质序列在97%序列相似度下进行聚类,应用Mothur软件在OTUs列表中根据样品的物种丰度情况计算各样品的丰富度和多样性指数。结果表明：（1）巢湖水样具有很高的细菌多样性,不同空间区域的群落结构存在差异;在门水平上,主要细菌类群有放线菌门（Actinobacteria）、变形菌门（Proteobacteria）、蓝细菌门（Cyanobacteria）、拟杆菌门（Bacteroidetes）和浮霉菌门（Planctomycetes）;在属水平上,主要细菌类群有hgcI clade、微胞藻属（Microcystis）、CL500-29 marine group和unclassified OPB56;3个样点均存在大量未知的菌属。（2）裕溪河出湖口总氮、总磷和COD含量较高,球衣菌属（Sphaerotilus）丰度相对较高;南淝河入湖口大量出现拟浮丝藻属（Planktothricoides）,说明此处污染仍然较严重;3个样点均检测出大量从毛单胞菌科无法鉴定到属的种类（unclassified Comamonadaceae）,指示巢湖不同空间区域的水体均受到外源污染物输入的影响。     

斑节对虾混养池塘微生物群落生态功能初探

利用宏基因组技术比较斑节对虾单独养殖、斑节对虾与海蜇混养、斑节对虾与海蜇和菲律宾蛤仔混养3种养殖模式池塘沉积物的微生物群落。试验结果显示,皮氏罗尔斯通氏菌为最主要的致病菌,斑节对虾养殖池塘沉积物中致病菌的丰度相比于对照组沉积物均明显下降。与非海水养殖池塘对照沉积物相比,斑节对虾养殖池塘沉积物的微生物群落中硝酸盐还原生成氨氮的相关基因以及硫酸盐还原产生硫化氢的相关基因含量更高,而亚硝酸盐和氨氮利用基因含量较低。3种斑节对虾养殖模式中,斑节对虾单独养殖和斑节对虾与海蜇和菲律宾蛤仔混养池塘沉积物中硝酸盐和硫酸盐还原基因丰度均高于斑节对虾与海蜇混养模式。此外,斑节对虾养殖池塘沉积物中,一些特定的生物地球化学循环过程由包括交替单胞菌、拟杆菌、着色菌、黄杆菌、脱硫杆菌和脱硫弧菌等多种微生物共同完成。探明不同斑节对虾养殖池塘微生物群落中潜在的人类致病菌情况以及氮、硫等基本元素的生物地球化学循环,对于优化养殖技术、控制疾病暴发同时提高养殖产量具有重要意义。     

不同养殖年份鱼塘底泥细菌群落多样性及演替分析

为探究不同养殖年份的鱼塘底泥中细菌多样性及演替关系,通过构建16S rRN A基因文库,比较分析养殖1年和养殖4年池塘底泥样品细菌的群落构成,分别由养殖1年和养殖4年文库获得145和172个克隆子,香农—威纳多样性指数分别为2．37和2．22,辛普森优势度指数分别为9．36和7．58,覆盖度指数分别为100％和93．3％。 Prolixibacter （34／145）、荚硫菌属（17／145）、浮霉菌属（15／145）和脱硫微菌属（12／145）为养殖1年样品优势菌群,长绳菌属（41／172）、Prolixibacter （31／172）、黄色单胞菌属（22／172）、Cetobacterium （21／172）和噬纤维菌属（15／172）为养殖4年样品优势菌群。养殖1年和养殖4年文库细菌菌群结构在种分类水平上的相似度系数为0．6171。由此可知,养殖池塘底泥中蕴含着复杂的微生物群落体系,长期的积累促使该微生物群落发生了演替。     

小湾库区微生物群落结构多样性与水质状况分析

为了解小湾库区水域微生物多样性,通过16S rDNA基因扩增和高通量测序分析了小湾库区6个采样点水域微生物群落结构组成及多样性差异。结果显示,小湾库区水体整体呈偏碱性,且含氧量丰富,COD含量为14.79~24.47 mg/L,TN浓度为0.53~2.39 mg/L,TP浓度为0.14~1.17 mg/L。不同采样点微生物Chao1指数、覆盖率均较高,Shannon指数为3.42~4.48,Simpson指数为0.029 8~0.091 9,反映出各采样点微生物群落多样性丰富,其中群落丰富度以W06区域最高。各采样点的菌门主要有变形菌门(Proteobacteria)、蓝细菌门(Cyanobacteria)、放线菌门(Actinobacteria)、拟杆菌门(Bacteroidetes)和绿弯菌门(Chloroflexi),丰度之和可达90%以上,且以变形菌门为优势菌门；在属水平上以不动杆菌属(Acinetobacter)为第一优势菌属。POCA分析表明,W05、W06区域聚为一类,而W01、W02、W03、W04区域聚为一类,具有显著差异。结果表明,小湾库区水域整体水质状况良好,但部分区域已出现水体富营养化现象且有扩散趋势,需采取环境治理措施。从渔业可持续发展来看,应通过合理放养、合理捕捞的方式,充分利用水域中天然饵料资源,在保证小湾库区水力发电的正常运行的前提下,适当开发小湾库区渔业潜力。     

浑河流域硅藻群落多样性的研究

通过对辽宁省浑河流域60个采样点位的着生硅藻进行调查研究,并利用硅藻香农维纳指数、均匀度指数及硅藻商对浑河水质进行评价,结果显示:浑河流域共鉴定出硅藻种类20属167种,以羽纹纲中的菱形藻属、脆杆藻属、舟形藻属为主。硅藻细胞密度115.40~61 231.19ind./cm2,平均值为8 981.56ind./cm2。硅藻香农维纳指数范围0.29~1.61,均匀度指数范围在0.012~0.341,硅藻商值范围为0~2.70。浑河流域着生硅藻香农维纳指数和均匀度指数相对较低。通过综合评价认为浑河流域水体受到不同程度污染,需加大保护力度。     

济南流域轮虫群落结构及多样性的研究

通过对山东省济南流域19个采样点位的轮虫进行调查研究并利用轮虫香农维纳指数、均匀度指数对济南水质进行评价,结果表明:济南流域共鉴定出轮虫种类17属30种,主要以龟甲轮属和臂尾轮属为主。轮虫密度2.0~453.0ind./L,平均值为114.4ind./L。轮虫香农维纳指数和均匀度指数都具有显著的空间分布规律,香农维纳指数范围为0.917~3.644,平均值为2.752;均匀度指数范围为0.857~1.608,平均值为0.881。济南流域轮虫香农维纳指数和均匀度指数相对较低,通过综合分析认为济南流域水体受到不同程度污染。     

三峡大坝对香溪河底栖微生物群落结构和多样性的影响

为了研究三峡大坝修建后库区生态环境的变化,探究大坝修建对库区底泥细菌群落结构和多样性的影响,2013年夏季在香溪河回水区(河口、中游)与河流区(上游)依次选取6个采样点,通过构建16S r DNA基因克隆文库,分析底栖微生物群落结构和多样性的变化规律。结果表明,香溪河调查水域共检出细菌类群15门、87属。在门水平上,回水区和河流区的优势菌门均为变形菌门;在属水平上,回水区和河流区的优势菌属存在显著差异(P0.05),很可能是由于受长江回水和支流高岚河影响所致。芽孢杆菌属所占的比例,从回水区的河口处至中游处逐渐减少至河流区消失,结合芽孢杆菌属易生活在底泥深处的特性,很可能由于大坝的修建,香溪河的上游(即河流区)底泥冲刷至下游(即回水区)河段,被三峡大坝拦截而沉积下来,导致越靠近大坝处,芽孢杆菌属的含量越高。在底泥细菌群落多样性中,Simpson、Shannon和Margalef多样性指数空间分布总体上呈"中间高、两头低"的规律;3种多样性指数最高的采样点均出现在回水区,且回水区的多样性指数均高于河流区,很可能是因其还与旧州河、卜庄河以及周溪河这些支流的交汇,导致河流区底泥细菌群落多样性不稳定。三峡大坝对香溪河底栖微生物的群落结构和多样性产生了显著影响,而大坝修建导致库区回水区水深增加、流速降低、底层水温变化、泥沙沉积增加等因素是造成这种差异的可能原因。     

蜡样芽孢杆菌对对虾养殖水体微藻群落的调控研究

运用实验生态学方法分析了溶藻细菌——蜡样芽孢杆菌(Bacillus cereus)CZBC1对对虾养殖水体微藻群落的影响。根据用菌量,实验分为J0组(不施菌)、J3组(用菌量3.00×10~3CFU·m L~(-1))和J5组(用菌量3.00×105CFU·m L~(-1)),每组3个平行,各实验水体优势种绿色颤藻(Oscillatoria chlorine)和波吉卵囊藻(Oocystis borgei)的初始优势度为64.14%和16.42%,实验周期15 d。结果显示,经过15 d的实验,J0组绿色颤藻优势度显著高于J3组和J5组(P0.01),波吉卵囊藻优势度显著低于J3组和J5组(P0.01)。其中,J0组绿色颤藻优势度升高至81.86%,J3组和J5组则分别降低至16.7%和14.6%;J0组波吉卵囊藻优势度降低至3.13%,J3组和J5组则分别升高至32.42%和47.14%。J0组、J3组和J5组对虾死亡率在第6天时分别为82.2%、46.7%和31.1%,J0组显著高于J3组和J5组(P0.01),第15天时J0组仍然高于J3组和J5组。可见,CZBC1可有效抑制绿色颤藻(蓝藻)的生长,从而为波吉卵囊藻(绿藻)占据生态优势提供有利空间,为养殖对虾提供良好的水生态环境。     

黄、东海冬季底层鱼类群落结构及多样性变化

根据1991年和2000年冬季在黄海中南部和东海中北部海域进行的底拖网调查资料，对黄、东海底层鱼类群落的资源状况、重要种类的生态优势度与结构、多样性及其空间分布格局等方面的动态变化进行了分析。结果表明，生物量指数明显下降，个体小型化使生物资源密度显著上升；重要种类成分发生演替，优势度有较大变化；物种丰富度指数(D)下降极其显著，Shannon—Wiener多样度指数(H′)也有所下降，但不显著。     

Effects of microbial products and extra carbon on water quality and bacterial community in a fish polyculture system

A 55‐day mesocosm experiment was conducted to evaluate the effects of commercial microbial products (Novozymes Pond Protect and Novozymes Pond Plus) and extra carbon (glucose) on water quality and bacterial community in a fish polyculture system. A 2 × 2 layout, including four treatments (non‐supplementation of the microbial products or glucose, adding glucose, adding the microbial products and adding the microbial products and glucose in combination), was established. The microbial products and glucose were added on the 40th day, 46th day and 52th day. Ammonia, nitrite and nitrate reduced in the tanks after glucose addition, while adding the microbial products did not significantly affect ammonia, nitrite, nitrate, reactive phosphate, total nitrogen, total phosphorus, chemical oxygen demand and total organic carbon. Adding the microbial products and glucose affected relative abundance of some bacterial taxa, but did not reshape bacterial community. Non‐positive interactive effect on water quality and bacterial community was detected between the microbial products and glucose. This study reveals that supplementation of the microbial products did not benefit water quality in the fish polyculture system, and glucose addition could reduce ammonia, nitrite and nitrate.     

Effect of three commercial microbial products on bacterial community in a freshwater fish polyculture system

A 30‐day experiment was conducted to evaluate the effect of three commercial microbial products, Novozymes Pond Plus, Zhongshui BIO‐AQUA and Effective Microorganisms on bacterial community in polyculture tanks stocked with grass carp (Ctenopharyngodon idellus), gibel carp (Carassius auratus) and silver carp (Hypophthalmichthys molitrix). Four treatments were tested. One treatment with no supplementation of the microbial products served as control. In the other three treatments, the microbial products were added at the intervals of 10 days respectively. During the experiment, grass carp and gibel carp were fed with a commercial formulated feed daily. Bacterial count and bacterial composition in water column of the tanks were monitored at the intervals of 3 days, and bacterial composition in sediment was determined at the end of the experiment. Bacterial composition in water column varied with progress of the experiment. Some bacteria from Novozymes Pond Plus and Effective Microorganisms could colonize in the tanks but did not dominate in bacterial community. This study reveals that the competition between the exogenous bacteria and native bacteria might be a factor determining the efficacy of the microbial products in improving water quality.     

Effect of disinfection with peracetic acid on the microbial community of a seawater aquaculture recirculation system for Pacific white shrimp (Litopenaeus vannamei)

When tropical shrimps are kept in recirculating aquaculture systems (RAS), one of the limiting factors is the maintenance of a sufficient water quality, and therefore, often disinfectants like peracetic acid (PAA) are added to the water either as prophylactic or treatment measure. In this study, PAA in concentrations of 0.1 mg/L, 1 mg/L and 10 mg/L was applied continuously for 56 days to small-scale seawater RAS stocked with Litopenaeus vannamei. Treatment with 0.1 mg/L did not result in a reduction in the total bacterial amount and therefore was not effective. A concentration of 10 mg/L led to significant changes in the chemical water parameters already after 2 days and was therefore not recommendable. A concentration of 1 mg/L led to increased levels of ammonia and nitrite within 2 days and to a significant increase in the bacterial amount in the water, most probably due to an enhanced growth of heterotrophic bacteria. The microflora showed significant fluctuations, and there were indications that the welfare of the shrimps was affected. Using 1 mg PAA/L for prophylactic use is therefore also not recommendable but might be an alternative option for short-term treatment in cases of disease outbreaks.     

Effects of carbon source addition on microbial community and water quality in recirculating aquaculture systems for Litopenaeus vannamei

Fisheries Science - In order to study the effects of carbon source addition on the bacterial community, water quality and shrimp growth in the recirculating aquaculture system of Litopenaeus...     

Effects of biological water purification grid on microbial community of culture environment and intestine of the shrimp Litopenaeus vannamei

Biological water purification grid (BWPG), a type of biofilm, could increase aquaculture production by improving the growth of shrimp and culture environment. In this study, the microbial community composition and diversity of water, sediment and shrimp intestine were analysed using the Illumina Miseq high‐throughput sequencing technique. Installation of BWPG did not only increase the dissolved oxygen, pH and decreased inorganic nutrients, but also increased shrimp body length by 5.39% and weight by 16.35%. Furthermore, it was found that the microbial community diversity of water and shrimp intestine in test pond with BWPG was higher than that of control pond without BWPG. Cyanobacteria, Bacillus and Lactococcus were enriched in the test pond with BWPG. However, Rhodobacter was mainly identified in the test pond. It thus seems to suggest that the application of BWPG in shrimp culture pond enhanced the microbial species richness, types of species and proportion of beneficial bacteria in culture environment as well as shrimp intestine. The results from this study will therefore provide some scientific basis for the improvement and development of shrimp aquaculture.     

Bacterial composition,abundance and diversity in fish polyculture and mussel–fish integrated cultured ponds in China

Bacterial community and abiotic environmental parameters in twelve freshwater aquaculture ponds were analysed. According to the major component of stocked animals, the ponds were grouped into four types: black carp Mylopharyngodon piceus, largemouth bass Micropterus salmoides, yellow catfish Pelteobagrus fulvidraco and pearl mussel Hyriopsis cumingii ponds. Each type of pond was stocked with three species of Chinese carps (silver carp, bighead carp and gibel carp) to form a unique mode of fish polyculture or mussel–fish integrated culture. The bacterial composition was identified using 16S rDNA sequencing. Totally, 3701 and 11 150 operational taxonomic units (OTUs) were identified from the water and sediment samples respectively. The number of OTUs, abundance‐based coverage estimator, Chao1 index and Shannon diversity index were lower in the water column than in the sediment, suggesting that diversity and stability of bacterial community were higher in the sediment. In the water column, Proteobacteria, Actinobacteria and Bacteroidetes dominated at the phylum level, and 26 dominant genera were identified. In the sediment, Proteobacteria, Chloroflexi, Bacteroidetes, Acidobacteria and Nitrospirae dominated at the phylum level, and 25 dominant genera were identified. Bacterial compositions between the ponds with different aquaculture modes were similar at the phylum levels, but varied at the genus levels. The bacterial composition in the ponds was correlated with hardness, ammonia and total nitrogen in the water column. This study indicates that the type of aquaculture mode is a factor regulating the microbial community, which provides an insight towards microbial management through probiotic manipulation in pond culture.     

三疣梭子蟹、凡纳滨对虾、菲律宾蛤仔和江蓠混养结构优化的实验研究

利用海水陆基实验围隔优化了三疣梭子蟹(Portunus trituberculatus)、凡纳滨对虾(Litopenaeus vannamei)、菲律宾蛤仔(Ruditapes philippinarum)和菊花江蓠(Gracilaria lichevoides)的混养结构。实验设6个处理组,分别为蟹-虾(CS)、蟹-虾-贝(CSB)、蟹-虾-贝-藻(CSBJ1、CSBJ2和CSBJ3),以梭子蟹单养为对照(C),每个处理组设置了4个重复。结果表明,各处理组梭子蟹个体规格差异不显著(P0.05),产量以CSBJ2处理组最高;CSBJ1和CSBJ2组凡纳滨对虾的平均体重、特定生长率以及成活率均显著高于其它处理组(P0.05);凡纳滨对虾产量以CSBJ2最高,显著高于其它处理组(P0.05);混养江蓠处理组菲律宾蛤仔成活率显著提高,但产量与其它处理差异不显著;养殖期间,CSBJ2处理组亚硝氮含量总体上显著低于其它处理(P0.05),混养江蓠各处理水体氨氮浓度养殖后期均显著降低(P0.05),而CSBJ1和CSBJ2组总氮和总磷浓度在中后期显著低于其它处理(P0.05)。本研究表明,虾蟹贝混养系统中搭配适宜密度的菊花江蓠,可以有效改善水质,减少水体中总氮、总磷浓度以及氨氮、亚硝氮等有害物质含量,提高梭子蟹和对虾的产量和成活率及菲律宾蛤仔的成活率。在本研究条件下,虾、蟹、贝和江蓠混养的最佳配比为三疣梭子蟹6ind/m2,凡纳滨对虾45ind/m2,菲律宾蛤仔30ind/m2和菊花江蓠0.36kg/m2。     

淡水池塘南美白对虾与鲻鱼生态混养技术研究

2017、2018年连续2年利用7口0.4 hm2(6亩)对虾养殖池在淡水条件下进行了鲻鱼与南美白对虾混养试验.试验结果:鲻鱼放养规格48～80 g/尾,放养密度为75～225尾/hm2,收获鲻鱼规格为420～520 g/尾.2017年,南美白对虾单养池(对照池)产量为6090 kg/hm2,6口鱼虾混养池产量分别比对...     

湖鲚体内与生长环境菌群PCR-DGGE指纹图谱及多样性分析

利用PCR-DGGE技术,选择细菌原核通用引物F357-GC和R518对太湖湖鲚(Coilia ectenes taihuensis)鳃、肠壁及肠内容物及其生长环境菌群结构进行了初步分析。结果显示:PCR-DGGE指纹图谱分离显示49条清晰条带,样品菌群丰富度(DGGE条带数):湖水(33)肠道壁(23)湖泥(18)肠道内容物(16)=鳃(16);相应的香农多样性指数分别为:3.11、2.76、2.21、2.37、2.30。湖鲚肠道壁、肠道内容物和鳃与湖水分别具有14、14、10条共有带,切胶回收测定其中21条优势条带,主要包含:变形菌(Proteobacteria)、放线菌(Actinobacteria)、拟杆菌(Bacteroidetes)、柔膜菌(Tenericutes)、蓝藻细菌(Cyanobacteria)、厚壁菌(Firmicutes)。结果表明PCR-DGGE指纹图谱能够清晰显示湖鲚不同部位及其生长环境细菌群落结构和区分其菌群结构差异,并阐明生长水域环境是影响湖鲚体内细菌菌群结构组成的主要因素之一。     

不同消毒剂对凡纳滨对虾育苗水质和菌群结构的影响

该研究使用碘(I2)、二氧化氯(ClO2)、甲醛溶液(HCHO)和漂白粉[Ca(ClO)2]4种常用消毒剂对凡纳滨对虾(Litopenaeus vannamei)育苗海水处理后,研究了不同发育期育苗水体总菌和弧菌数量、氨氮和亚硝酸氮含量、幼体成活率以及水体和幼体菌群的变化.结果显示:1)甲醛组水体的总菌数较低,且弧菌数...