仿刺参养殖池塘浮游病毒丰度与环境因子的相关性分析

为了揭示仿刺参养殖池塘生态系统中浮游病毒与环境因子的关系,于2008年3—11月对大连市谢屯地区的仿刺参养殖池塘中的浮游病毒丰度进行了定期检测,同时对水温、pH、溶解氧、盐度、叶绿素a含量、化学需氧量、无机氮、活性磷酸盐、异养细菌等因子进行了监测,对浮游病毒丰度与这些环境因子之间的相关性进行了分析。结果表明:仿刺参养殖池塘中浮游病毒的平均丰度为8.32×1010VLPs.L-1(最高值为4月的18.2×1010VLPs.L-1,最低值为11月的1.31×1010VLPs.L-1),外海水中浮游病毒平均丰度为6.45×1010VLPs.L-1(最高值为4月的12.6×1010VLPs.L-1,最低值为6月的2.02×1010VLPs.L-1),仿刺参养殖池塘中营养盐、水温、pH及盐度对浮游病毒丰度的影响较大,而外海水中叶绿素a和异养细菌对浮游病毒丰度的影响较大。     

典型河蟹养殖池塘不同养殖阶段水体微塑料特征

研究对典型河蟹养殖池塘水体在不同养殖阶段的微塑料丰度和赋存特征进行了研究。河蟹养殖池塘中微塑料丰度处于200—1640个/m³的水平,在全国与世界范围内处于中等水平。养殖前中期微塑料丰度较低,而养殖末期微塑料丰度较高。河蟹养殖周期中的引水和排水过程、养殖过程中塑料制品的使用和老化及养殖过程中水环境的变化都可能对河蟹养殖池塘的微塑料丰度变化产生影响。而养殖过程不仅影响了微塑料丰度,还影响了河蟹养殖池塘的微塑料特征,微塑料的形状、粒径、颜色及聚合物类型都在不同养殖期发生变化。研究进一步揭示了水样养殖过程中微塑料生成和变化的过程和机制。养殖末期较高的微塑料丰度表明可能需要关注养殖尾水排放对天然水体微塑料赋存的影响。     

长江口及邻近海域夏、冬季浮游病毒丰度分布

应用荧光显微计数法,对2006年夏季和2007年冬季长江口浮游病毒丰度(virus direct count,VDC)进行了检测.结果表明:夏季该海域VDC在2.22×106～9.97×107个·ml-1,高值分布在近海B区(122.5°-123.5°E)的表层海域;冬季VDC在1.99×106～2.66×107个·ml-1,高值分布在近岸A区(120.5°-122.5°E)海域,且由近岸向外海逐渐降低.夏季VDC与浮游细菌生物量、叶绿素含量关系密切,与营养盐相关性不显著(P＞0.05);冬季VDC与浮游细菌、营养盐含量关系密切,与叶绿素a含量相关性不显著(P＞0.05).夏季VDC显著高于冬季(P＜0.01),且两季的分布特征存在不同,此种差异主要与浮游细菌、浮游植物等病毒寄主的分布有关.冬季的营养盐含量也是影响其浮游病毒分布的重要因素.     

纳帕海高原湿地浮游病毒丰度及其与可溶性有机碳关系

【背景】浮游病毒在有机碳循环中具有重要作用。【目的】研究纳帕海高原湿地不同季节水样及土样中的浮游病毒和细菌丰度,并分析不同季节浮游病毒丰度与可溶性有机碳的关系。【方法】利用荧光显微镜技术检测不同季节水样中浮游病毒和细菌丰度,利用流式细胞仪技术检测不同季节土壤样品中病毒颗粒和细菌丰度。【结果】雨季所有样品浮游细菌和浮游病毒丰度分别为3.38×10~6/mL和4.38×10~7/mL,旱季所有样品的浮游细菌和浮游病毒丰度分别为8.85×10~5/mL和9.66×10~6/mL,浮游细菌和浮游病毒丰度年平均值分别为2.13×10~6/mL和2.67×10~7/mL。不同季节浮游细菌和浮游病毒的丰度有显著性差异,雨季明显高于旱季(P0.01)。雨季细菌碳产量为8.01μg C/(L·h),旱季为10.30μg C/(L·h)。雨季浮游病毒裂解细菌贡献的可溶性有机碳(Dissolved organic carbon,DOC)占总DOC库的32.38%-76.38%,而旱季为8.23%-47.87%。【结论】浮游病毒在纳帕海高原湿地有机碳循环中具有重要作用。     

纳帕海高原湿地浮游病毒丰度及与环境因子相关性研究

目的 利用EFM技术对纳帕海湿地不同季节7个水样样品中的浮游病毒丰度开展了调查,并对影响浮游病毒丰度的环境因子进行了相关性分析。方法 元素检测,叶绿素a检测,荧光显微镜检测浮游细菌及浮游病毒的丰度。结果 从生态分布上来看旱季和雨季浮游病毒丰度的平均值分别为3.63×106/mL和3.71×107/mL,浮游病毒丰度季节性变化不显著。从对影响浮游病毒丰度的环境因子相关性分析来看,旱季浮游病毒与Chl-a具有弱负相关性（r=0.49,P<0.05）;而雨季浮游病毒丰度与Chl-a具有显著正相关性（r=0.37,P<0.05）,表明雨季纳帕海湿地浮游病毒丰度受Chl-a含量的影响较大。旱季浮游病毒丰度与温度显著负相关,虽然在雨季浮游病毒丰度与温度也呈负相关,但并不显著;在雨季,水体pH变化较明显,而浮游病毒丰度与水体pH呈显著负相关,表明湿地的来水主要在雨季,而离子组成变化大。虽然在雨季和旱季,从多点采样的平均值来看浮游病毒丰度并无明显差异,但从一些局部的采样点来看,雨季的浮游病毒丰度显著高于旱季,说明在纳帕海区域浮游病毒的分布并不平均,因采样点环境的不同会产生明显的区别。结论 对纳帕海高原湿地浮游病毒生态分布的调查,是对该地域生态学研究的补充,使得这一独特地理环境的微生物研究更加系统化。     

刺参养殖池塘颗粒悬浮物结构及其沉积作用

对不投饵刺参养殖池塘的颗粒悬浮物结构及其沉积量和沉积速度进行了研究.结果表明:(1)各池塘总颗粒悬浮物重量(TS)为(73.1±20.5)mg/L,变动于46.0～132.0mg/L之间;颗粒无机物(IS)含量为(50.6±12.6)mg/L,变动于28.5～76.5mg/L之间,占总颗粒悬浮物的69.13%;浮游生物干重(PZ)为(0.675±0.706)mg/L,变动于0.064～2.814mg/L之间,其中浮游植物干重(DWP)为(0.541±0.622)mg/L,变动于0.062～2.582mg/L之间,浮游动物干重(DWZ) 为(0.135±0.200)mg/L,变动于0.002～1.160mg/L之间;颗粒腐质为(21.91±19.59)mg/L,变动于4.18～83.86mg/L之间,占总颗粒悬浮物的比例为29.95%.(2)总颗粒物沉积量为(19.44±16.34)g·m-2·d-1,变动于6.33～91.98g·m-2·d-1之间,沉降速度为(0.30±0.30)m·d-1,变动于0.08～1.63m·d-1之间,新生态颗粒有机物沉积量为(5.09±7.30)g·m-2·d-1,变化于0.14～31.27g·m-2·d-1之间,总颗粒物沉积量和新生态颗粒物沉积量均是底层高于表层.     

刺参养殖池塘初级生产力及其粒级结构周年变化

研究了刺参(Apostichopus japonicus Selenka)养殖池塘浮游植物初级生产力及粒级结构的周年变化规律,旨在明确刺参养殖池塘的基础生态学特征,为刺参养殖生产和管理提供科学支持。结果表明:刺参养殖池塘初级生产力年平均值为(5.16±3.04)gO2m-2d-1,全年呈现明显的季节变化,初级生产量分别在初春、夏季和初冬形成高峰。初级生产力群落净产量占毛产量的50.2%。P/R值与日P/B系数的年平均值分别为2.20±1.25和0.39±0.35。按初级生产力水平和P/R值划分的水体营养类型,调查刺参养殖池塘属富营养型水体;初级生产量随深度的增加而递减,最高生产层约在透明度的0.5倍处,且0.5倍透明度(约50 cm)以上水层初级生产量占水柱总产量的56.3%;不同粒级浮游植物生产量占总生产量的百分比具有明显的季节变化。除夏季外,以小型浮游植物(micro-,20—200μm)对初级生产力的贡献最大(43.5%),夏季为微型浮游植物(nano-,2—20μm)对初级生产力贡献最大(35.3%)。以年平均值计算,不同粒级浮游植物初级生产量占总生产量百分比的大小顺序为:小型(40.1%)微型(28.2%)中大型(16.1%)超微型(15.7%)。回归分析表明:试验池塘初级生产力水平与水温、营养盐中的氨氮和亚硝酸氮均呈显著的相关关系(P0.05)。结果提示,刺参养殖池塘初级生产力的季节变化显著,垂直分布并不均匀,小型浮游植物是其生态系统中的主要生产者。     

刺参养殖池塘水体微生物群落功能多样性的季节变化

利用Biolog技术和冗余分析(RDA)方法对刺参养殖池塘水体微生物群落功能多样性的季节变化及其与环境因子间的关系进行研究.结果表明： 刺参池塘水体微生物对碳源总量和单类碳源的利用均具有显著的季节变化,总体表现为夏季最高、冬季最低,其利用比例较高的碳源类型为聚合物.主成分分析表明,刺参池塘水体微生物群落碳代谢方式具有显著的季节变化,其中,与主成分1显著相关的碳源主要有10种,分别属于聚合物、糖类、羧酸、氨基酸和胺.刺参池塘水体微生物碳代谢多样性指数Shannon、McIntosh、Simpson和S E均匀度均存在显著的季节变化,但不同指数之间的变化有较大差异.RDA分析表明,TP、NO₃^--N、TN和PO₄^3--P是影响刺参池塘水体微生物群落功能多样性季节变化的主要因素.     

中华鲟在成都地区池塘养殖试验报告

１９９３－１９９５年,在四川郫县省水产研究所进行了中华鲟的池塘养殖试验,基本摸清了中华鲟稚幼鱼在内塘里的生活习性及生长特点。全长约３ｃｍ的稚鱼经过１１３ｄ的培育,平均全长为２４ｃｍ,最大个体全长可达２７ｃｍ,体重６０ｇ。幼鱼经过７个月的饲养后鱼体平均全长可达７４ｃｍ,平均体重为１．９ｋｇ。继续饲养一年后,鱼体平均全长为９７．５ｃｍ,体重３．３ｋｇ。最大个体全长１１０ｃｍ,体重５ｋｇ以上。通过两年的     

罗氏沼虾池塘养殖技术

罗氏沼虾(Macrobrachium rosenbergii)又名马来西亚大虾,隶属沼虾属,长臂虾科,十足目,甲壳纲,原产于印度、太平洋热带和南亚热带地区,具有生长快、个体大、易养殖、营养丰富、经济价值高等优点。四川省自然资源研究所与美国海星国际公司、广汉市水产站1989年共同开发罗氏沼虾获得初步成功,大面积养殖平均亩产达100kg左右,最高达亩产150kg。本文就罗氏沼虾池塘养殖技术作简要介绍。     

Seasonal Variation of Virioplankton in a Eutrophic Shallow Lake

Lake Donghu is a typical eutrophic freshwater lake in which high abundance of planktonic viruses was recently revealed. In this study, seasonal variation of planktonic viruses were observed at three different trophic sites, hypertrophic, eutrophic, and mesotrophic regions, and the correlation between their abundances and other aquatic environmental components, such as bacterioplankton, chlorophyll a, burst size, pH, dissolved oxygen, and temperature, was analyzed for the period of an year. Virioplankton abundance detected by transmission electron microscope (TEM) ranged from 5.48 × 10⁸ to 2.04 × 10⁹ ml⁻¹ in all the sites throughout the study, and the high abundances and seasonal variations of planktonic viruses were related to the trophic status at the sampled sites in Lake Donghu. Their annual mean abundances were, the highest at the hypertrophic site (1.23×10⁹ ml⁻¹), medium at the eutrophic site (1.19×10⁹ ml⁻¹), and the lowest at the mesotrophic site (1.02×10⁹ ml⁻¹). The VBR (virus-to-bacteria ratio) values were high, ranging from 49 to 56 on average at the three sampled sites. The data suggested that the high viral abundance and high VBR values might be associated with high density of phytoplankton including algae and cyanobacteria in this eutrophic shallow lake, and that planktonic viruses are important members of freshwater ecosystems.     

Zooplankton abundance and diversity in Central Florida grass carp ponds

The effect of the Asian grass carp (Ctenopharyngodon idella Val.) upon the zooplankton in three adjacent experimental ponds (0.139 ha each) was studied for one year. The ponds contained nine species of aquatic macrophytes. Grass carp were stocked into Pond 1 (65 per ha) and Pond 2 (611 per ha) three months after the study was started. At the time of stocking, physichochemical and biological parameters were similar among the ponds.Grass carp did not affect water quality and had little direct or indirect effect upon the zooplankton in the ponds. The abundance and species diversity of zooplankton (number of species, Shannon Index, and Simpson Index) were not significantly different (P < 0.05) between ponds prior to grass carp stocking. After stocking with grass carp, the number of species and species diversity were found to be significantly different (P < 0.05) between Pond 1 (low grass carp stocking rate) and Pond 2 (high grass carp stocking rate). Additionally, significant differences (P < 0.05) in populations between ponds were found for Lecane luna, Monostyla bulla, Lepadella ehrenbergii, Polyarthra sp., and Synchaeta sp. Temporal variation rather than grass carp was probably responsible for those differences. The number of zooplankton per group (Rotifera, Cladocera, and Copepoda) and species diversity were not significantly different (P<0.05) between ponds containing different stocking rates of grass carp.During the study, zooplankton were collected with a shallow-water sampler. No significant differences (P < 0.05) between collections were found for the sampler and a No. 20 mesh nylon zooplankton net.     

凡纳对虾淡化养殖虾池微型浮游生物群落及多样性

2 0 0 2年 8月 15～ 10月 8日 ,对广东省珠海市斗门凡纳对虾淡化养殖虾池进行调查 ,虾池平均养殖面积为 0 .37±0 .11hm2 ,水深 136± 8cm,虾苗放养密度 131± 37× 10 4尾 / hm2 ;调查期间虾池水温 2 4 .3～ 33.6℃ ,p H值 7.1～ 9.6 ,早期养殖盐度 2‰～ 3‰ ,中后期为 0 ,透明度中后期稳定在 2 0 cm左右。鉴定浮游植物 4 8属 96种 ,其中绿藻 4 5种 ,硅藻和裸藻各 9种 ,隐藻 2种 ,甲藻 4种。优势种有 10种 ,多为蓝藻 ,如螺旋藻 (Spirulina sp.)、弯形尖头藻 (Raphidiopsis curvata)、小颤藻(Oscillatoria tenuis)、假鱼腥藻 (Pseudoanabaena sp.)、针状蓝纤维藻 (Dactylococcopsis acicularis)及水华微囊藻 (Microcystisaeruginosa)等 ,优势种的优势度突出。常见种有 30种 ,主要是绿藻、硅藻、隐藻 ,少见种有 5 7种。优势种和常见种多为富营养化水体中的或耐污性的种类。虾池原生动物有 2 9种 ,其中肉足虫 3种 ,纤毛虫 2 6种 ,优势种为毛板壳虫 (Colepshirtus)、卵形前管虫 (Prorodon ovum)和旋急游虫 (Strombidium spiralis) ,主要是以藻类为食的 A类群 ,常见种有膜袋虫 (Cyclidium sp.)、小单环栉毛虫 (Didinium balbianitnanum)、瓶口虫 (L agynophrya acuminate)、圆筒状拟铃壳虫 (Tintinnopsis c     

Distribution and abundance of macroinvertebrates within two temporary ponds

We investigated the distributions of macroinvertebrates within two temporary ponds (Spring Peeper Pond and Taylor-Ochs Pond) in central Ohio and examined what environmental factors may be driving those distributions. We sampled macroinvertebrates in Spring Peeper Pond three times from May to July 2001, and Taylor-Ochs Pond two times from May to June 2001. Macroinvertebrate distributions were significantly aggregated on all sampling dates in both ponds. Bivalve abundance in Spring Peeper Pond was higher in shallower water. The distribution of bivalves in Taylor-Ochs Pond was not correlated with any variable we measured. Dragonfly nymph abundance in Taylor-Ochs Pond decreased between the first and second sampling dates, whereas in Spring Peeper Pond no factor examined was correlated with dragonfly nymph density. Snail densities in Spring Peeper Pond were negatively related to dissolved oxygen and depth. In Taylor-Ochs Pond, snail abundance was positively related to temperature. The densities of damselfly nymphs in Spring Peeper Pond were positively related to dissolved oxygen and depth and declined across the study. In Spring Peeper Pond, hemipteran densities were negatively related to depth and increased across the study. Damselfly nymphs and hemipterans were not common enough in Taylor-Ochs to analyze. In general, the abiotic and biotic factors we examined explained relatively little (<37% in all cases) of the within pond distribution of the macroinvertebrates in our two study ponds.     

Spatial and Temporal variations of mangrove fish assemblages in Martinique (French West Indies)

A study of the mangrove fish fauna in a bay of Martinique Island (French West Indies) was carried out at different seasons during two consecutive years. fishes were sampled with specific hoop-nets in the coastal areas at 8 stations.A total of 87 species was collected in the bay. Most individuals were represented by small-size specimens and juveniles. The overall species richness varied according to the stations and the sampling periods. The biomass and number of individuals were variable according to the location but remained stable in time. A factor correspondence analysis and a hierarchical clustering with median links were used to follow the evolution of the stations in space and time. Two types of stations were differentiated: the stations characterized by the mangrove and those under the influence of seagrass beds. A seasonal cycle, opposing the dry periods to the others, was observed.Thus, it seems that the use of the mangrove habitat by the fishes is optimized through a complete reorganization of communities in terms of species composition whereas the overall number and biomass remain stable. This model remains valid even for the most constraining biota of the mangrove ecosystem inhabited by a small number of well adapted species.     

Responses of species abundance distribution patterns to spatial scaling in subtropical secondary forests

To quantify and assess the processes underlying community assembly and driving tree species abundance distributions(SADs) with spatial scale variation in two typical subtropical secondary forests in Dashanchong state‐owned forest farm, two 1‐ha permanent study plots (100‐m × 100‐m) were established. We selected four diversity indices including species richness, Shannon–Wiener, Simpson and Pielou, and relative importance values to quantify community assembly and biodiversity. Empirical cumulative distribution and species accumulation curves were utilized to describe the SADs of two forests communities trees. Three types of models, including statistic model (lognormal and logseries model), niche model (broken‐stick, niche preemption, and Zipf‐Mandelbrodt model), and neutral theory model, were estimated by the fitted SADs. Simulation effects were tested by Akaike's information criterion (AIC) and Kolmogorov–Smirnov test. Results found that the Fagaceae and Anacardiaceae families were their respective dominance family in the evergreen broad‐leaved and deciduous mixed communities. According to original data and random sampling predictions, the SADs were hump‐shaped for intermediate abundance classes, peaking between 8 and 32 in the evergreen broad‐leaved community, but this maximum increased with size of total sampled area size in the deciduous mixed community. All niche models could only explain SADs patterns at smaller spatial scales. However, both the neutral theory and purely statistical models were suitable for explaining the SADs for secondary forest communities when the sampling plot exceeded 40 m. The results showed the SADs indicated a clear directional trend toward convergence and similar predominating ecological processes in two typical subtropical secondary forests. The neutral process gradually replaced the niche process in importance and become the main mechanism for determining SADs of forest trees as the sampling scale expanded. Thus, we can preliminarily conclude that neutral processes had a major effect on biodiversity patterns in these two subtropical secondary forests but exclude possible contributions of other processes.     

Species abundance distributions over time

It has been known for 50 years that the time period over which data are collected affects the shape of empirical species abundance distributions. However, despite a recent resurgence of interest in characterizing and explaining these patterns the temporal component of species abundance distributions has been largely ignored. I argue that it is essential to take account of time, and not only because sampling duration can have a profound influence on the perceived shape of the distribution. Partitions of species abundance distributions based on temporal occurrence in the record will facilitate tests of both biological and neutral models and may lead to a better understanding of rarity. These temporal partitions also have interesting, but as yet barely explored, parallels with spatial ones such as the core-satellite division. Moreover, changes in abundance distributions across all three of Preston's temporal scales (sampling time, ecological time and evolutionary time) present rich opportunities for ecological research.