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J. A. A. R. Schuurkes I. C. C. Heck P. L. G. M. Hesen R. S. E. W. Leuven J. G. M. Roelofs 《Water, air, and soil pollution》1986,31(1-2):267-272
In a greenhouse, seven identical mini-ecosystems, simulating soft water ponds, were exposed to different types of artificial rain water. The effects of rain water containing H2SO4 and nitrate, and rain water containing ammonium sulphate on water quality and vegetation were studied and compared. Causal relations were established between rain water quality, water chemistry and changes in floristic composition. Ammonium sulphate deposition, particularly, strongly affected water quality and vegetation development. Although ammonium sulphate deposition was only slightly acid, due to nitrification it acted as an important acid source, causing acidification to pH=3.8. Under acidified conditions, ammonium sulphate deposition lead to a luxuriant growth ofJuncus bulbosus andAgrostis canina. In the mini-ecosystems, H2SO4 deposition with a pH of 3.5 only decreased the pH of the water to 5.1 within 1 yr. The acidification of water appeared to be coupled with changes in alkalinity, sulphate, Al, Cd, Ca, Mg, K and inorganic-N. It is concluded that in NH3-affected regions in The Netherlands, the high atmospheric deposition of ammonium sulphate probably contributes to a large extent in the acidification, eutrophication and floristic changes of oligotrophic soft waters. 相似文献
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Meng Zhen Liu Xinfu Jia Yudong Liu Bin Yang Zhi Zhang Hesen 《Aquaculture International》2021,29(6):2575-2589
Aquaculture International - Tetraploid fish are the key source of diploid gametes in polyploid breeding, and they can be induced by disrupting the first mitotic cell cleavage. In this study, the... 相似文献
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Zhitao Huang Rong Wan Xiefa Song Ying Liu Eric Hallerman Dengpan Dong Jieming Zhai Hesen Zhang Liyuan Sun 《Aquaculture International》2016,24(5):1393-1408
While biofilters are widely used to metabolize ammonia and other metabolic waste products in recirculating aquaculture systems, their microbial communities are not thoroughly characterized. While inroads have been made characterizing microbial communities within single biofilters, replicated comparisons across biofilters and facilities have been lacking. We hypothesized that microbial communities might differ among filter types and facilities. We characterized and compared the bacterial communities of nine nitrification biofilters in five commercial recirculating marine aquaculture operations by amplifying and sequencing the 16S rRNA gene using the Illumina-MiSeq DNA sequencing platform. Our results demonstrated the usefulness of the approach for elucidating bacterial community structure in aquaculture biofilters; among almost 249,000 usable DNA sequence reads—a mean of 27,663 for each biofilter—we detected a mean of 682 operational taxonomic units. Higher species diversity was observed in the submerged biofilters at farms 3 and 4 (HF_SB1, HF_SB2, HF_SB3, MB_SB1, MB_SB2, and MB_SB3), and a bead filter at farm 2 (XYF-MBBR) than in a bead filter at farm 1 (DF_MBBR) and a fluidized sand filter at farm 5 (TY_FSF). At the phylum level, Proteobacteria were the most frequently observed taxa (representing 36–50 % of reads in the overall data set for a given filter); other frequently observed phyla were Bacteroidetes (13–34 %), Chloroflexi (2–23 %), Nitrospirae (1–7 %), Planctomycetes (1–4 %), and Actinobacteria (2–5 %). However, in fluidized sand filters, after Proteobacteria, the subdominant phyla were Bacteroidetes (19 %), Nitrospirae (17 %), and Planctomycetes (11 %). At the genus level, the nitrite-oxidizing genus Nitrospira was frequently observed in sand filter TY_FSF (16.4 %), bead filter DF_MBBR (7.6 %), submerged biofilter MB_SB1 (7 %), and bead filter XHF_MBBR (7.36), and less frequently in submerged biofilters HF_SB3 (1.94), HF_SB2 (1.77 %), and HF_SB1 (1.63 %), and bead filters MB_SB2 (0.8 %) and MB_SB1 (0.2 %). Observations of the ammonia-oxidizing genus Nitrosomonas varied widely within and among filter types, ranging from 0.06 % in submerged bed filter HF_SB3 to 2.82 % in bead filter DF_MBBR. Principal components and cluster analyses classified the bacterial communities in the nine biofilters into groups corresponding to the respective recirculating marine aquaculture operations and the associated filter types. 相似文献
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