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41.
42.
Comparison of bacterioplankton communities in three mariculture ponds farming different commercial animals in subtropical Chinese coast 总被引:1,自引:0,他引:1
In order to explore the responses of the bacterioplankton community to different types of aquaculture environments, three
mariculture ponds comprised of groupers (Epinephelus diacanthus, ED), prawns (Penaeus vannamei, PV), and abalone (Haliotis
diversicolor supertexta, HDS) in southeast, coastal China were investigated. The free-living bacterial diversity was analyzed through
the construction of 16S rDNA clone library. A total of 203 16S rDNA sequences from three clone libraries were classified into
118 operational taxonomic units (OTUs), of which 51, 31, and 42 OTUs were distributed in the ED, PV, and HDS pond, respectively,
with Bacteroidetes (30.6%), Actinobacteria (55.2%), and Cyanobacteria (32.8%) as the dominant division in the respective ponds. Meanwhile, each pond occupied some unique OTUs that were affiliated
with uncommon (sub-)phyla, such as candidate OP11 division, Acidobacteria, Deltaproteobacteria, Planctomycetes, and Verrucomicrobia. Bacterial diversity in the ED pond was the richest, followed by the HDS and the PV pond. OTUs of 61.9% and 94.9% have less
than 90% and 97% similarity to their nearest neighbors in public databases, respectively. All OTUs were grouped into 67 clusters,
covering 11 (sub-)phyla. The OTUs only from single pond distributed in 53 clusters (79.1%), the OTUs shared by two ponds were
affiliated with 14 clusters (20.9%), and none of clusters was formed by the OTUs which commonly originated from the three
pond libraries, suggesting that the composition of bacterial populations in these ponds were significantly different. These
results indicate that the aquatic environment created by different mariculture animals may foster very special and complex
bacterial communities.
Handling editor: David Philip Hamilton 相似文献
43.
Water levels were recorded weekly from six natural vernal pools and 10 created vernal pools at two forested wetland complexes
in central Ohio. Vernal pool median water depth and duration of inundation were significantly greater at the created vernal
pools than at the natural vernal pools (α = 0.05, P < 0.05). The average period of inundation for created pools was 309 ± 32 days, compared with 250 ± 16 days for natural pools.
The created pools produced a range of inundation times, from 163 to 365 days in length, with three pools permanently inundated. 相似文献
44.
Biological kinetic (bio-kinetic) study of the anaerobic stabilization pond treatment of palm oil mill effluent (POME) was carried out in a laboratory anaerobic bench scale reactor (ABSR). The reactor was operated at different feed flow-rates of 0.63, 0.76, 0.95, 1.27, 1.9 and 3.8 l of raw POME for a day. Chemical oxygen demand (COD) as influent substrates was selected for bio-kinetic study. The investigation showed that the growth yield (YG), specific biomass decay (b), maximum specific biomass growth rate (μmax), saturation constant (Ks) and critical retention time (Θc) were in the range of 0.990 g VSS/g CODremoved day, 0.024 day−1, 0.524 day−1, 203.433 g COD l−1 and 1.908 day, respectively. 相似文献
45.
46.
鄱阳湖围垦区藕塘越冬白鹤的时间分配与行为节律 总被引:1,自引:0,他引:1
2016年12月—2017年3月,采用瞬时扫描法研究了鄱阳湖围垦区藕塘生境中白鹤Grus leucogeranus越冬期的行为,共扫描2560次,23219只次,包括18031只次成鹤和5188只次幼鹤。结果表明,觅食(41.78%)、警戒(25.02%)、修整(15.00%)和休息(10.84%)是白鹤越冬期的主要行为。与自然生境相比,藕塘生境中白鹤主要采取多休息和修整的策略来节省能量支出。成鹤的觅食行为(35.29%)显著低于幼鹤(62.42%)(F_(1,12)=45.977,P0.01),警戒行为(28.66%)则显著高于幼鹤(10.26%)(F_(1,12)=38.975,P0.01)。家庭群成鹤觅食行为(43.96%)极显著高于非家庭群成鹤(27.04%)(F_(1,12)=60.169,P0.01)。家庭群成鹤需要喂食幼鹤,它们花费更多的时间觅食弥补能量的消耗。行为节律上,白鹤各时段觅食行为占总行为的比例均较高,11:00—11:59出现明显高峰,占总行为的48.64%。警戒行为无明显的低谷和高峰。成鹤在各时段的觅食行为比例均明显低于幼鹤,成鹤和幼鹤的觅食曲线变化趋势相似,即觅食比例的升高和降低比较同步。成鹤在各时段的警戒行为和修整行为比例均明显高于幼鹤,成幼鹤的休息行为比例在各时段差别不大,均在14:00—14:59有个明显的高峰。家庭群成鹤的觅食行为比例几乎在各时段均明显高于非家庭群,家庭群成鹤的修整行为和休息行为在大部分时段均低于非家庭群成鹤。因此家庭群成鹤采取多取食,少休息和修整的策略提高自身的适合度,同时保证对后代的抚育。 相似文献
47.
48.
应用草型塘模型生态系统研究化学品的整体生态效应 总被引:5,自引:1,他引:4
本文叙述草型塘模型生态系统的结构、功能及应用于评价化学品引起生态效应的可能性。模型塘由8个3m×1m×1m(V=3m ̄3)的玻璃钢水槽组成。每个槽的底部铺设10cm厚的带有水生生物种子、孢子和卵子的河泥,灌注自来水,添加一定量的KNO_3和NaH_2PO_4.使起始氮、磷含量达到中-富营养水平。在室外自然光照条件下培养,实验历时4个多月。经1个多月的培养,各槽即形成结构复杂的沉水植物群落,除各种常见的沉水植物外,尚有多种藻类、浮游动物、底栖动物及微生物。各群落之间的相似性较好,藻类、浮游甲壳类及底栖动物多样性指数变异系数分别为17.7%、18.0%和36.0%。群落功能稳定,9月中旬各槽群落总产氧量平均为5.75±0.30g/m ̄2·d’P/R比值平均为1.26±0.07,二者的变异系数分别为5.2%和5.6%。经单甲脒农药污染影响实验,本模型生态系统中的群落结构及功能产生一系列明显反应。说明草型塘模型生态系统结构、功能比较复杂,稳定,可比性较强,对药物污染反应灵敏,是生态系统水平上生态效应评价的良好工具。 相似文献
49.
盐碱池塘细巧华哲水蚤对浮游植物的摄食生态研究 总被引:10,自引:4,他引:6
利用常规显微镜直接计数法和叶绿素 a法研究了盐碱池塘细巧华哲水蚤 ( Sinocalanustenellus)对浮游藻类的原位摄食率及其影响因素。测得该水蚤对水柱浮游植物的滤水率为 1 .73~ 1 5 5 .1 6μl/ ( ind.· h) ,摄食率为 92~ 2 5 38cell/( ind.· h)或 0 .7~ 2 7.7ng C/ ( ind.· h)。两种方法测定的滤水率和摄食率基本相符 ( p>0 .5 ,t检验 )。该水蚤可有选择地滤食诸如小色球藻、光甲藻、绿裸藻 ,单生卵囊藻和小环藻等 ,其选择性指数分别为 0 .81、0 .75、0 .72、0 .6 1和 0 .35。不同光处理下细巧华哲水蚤的滤食率多数情况是无光时摄食率高。在本实验的条件下该水蚤在饥饿后的滤水率和摄食率与正常情况相比均显著降低 ( P<0 .0 1 ,t检验 )。 相似文献
50.
Detection of Nitrosomonas spp. by polymerase chain reaction 总被引:2,自引:0,他引:2
Abstract A unique genomic DNA fragment was isolated from Nitrosomonas europaea ATCC 19718. Based on the sequence of this fragment, oligonucleotide primers for polymerase chain reaction amplification were prepared which amplify sequences of 775 and 658 bp. The predicted DNA fragments were both amplified from the genome of N. europaea and a Nitrosomonas spp. isolated from a local oxidation pond. The primers failed to amplify DNA from the genomes of the ammonia oxidiser Nitrosolobous multiformis , the nitrite oxidiser Nitrococcus mobilis as well as from the genomes of other unrelated heterotrophic bacteria. These DNA sequences could be amplified from 0.01 ng of N. europaea genomic DNA or from 100 intact cells, and it was possible to detect Nitrosomonas DNA in a DNA mixture extracted from water samples drawn from a local oxidation pond. 相似文献