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Diatoms are one of the most important group of phytoplankton and benthic algae in the waters of marine aquaculture, plays an extremely important ecological role in the breeding waters material circulation and energy flow, is to understand the productivity of the breeding waters, increased breeding capacity, improving an important foundation of the culture environment. By taxonomic study of different types of marine aquaculture waters diatoms, and non-breeding areas, and clarify the diatom species diversity in marine aquaculture waters in this particular environment, classification feature, community structure characteristics, ecological distribution and seasonal succession laws, reveals the important status and role of diatoms in marine aquaculture waters. In the period from May 2003 to February 2005, the project collected planktonic and benthic diatom samples representative of marine aquaculture in China's coastal area, mainly including: the Liaoning Dalian zhangzi Island, Shandong of the Sanggou Bay, Jiaozhou Bay, Rushan Bay, Tang Island Bay, Zhoushan, Zhejiang Sanmen Bay, Tongan Bay, Fujian Quanzhou Bay; Guangdong Daya Bay, first class, a total of 170 were collecting samples. The culture environment covering shrimp, scallops breeding the breeding (Zhuhai Lepidosaphes), cage culture (grouper, red-brown fish), kelp hanging oyster breeding waters. Harbour select a specific culture zones, such as: Xike cage culture area monthly anniversary of sampling; Quanzhou Donghai shrimp ponds monthly quarterly sampling. On the samples collected after acid treatment, in the optical microscopy (LM) and transmission electron microscopy (TEM), scanning electron microscopy (SEM) under observation, counting and photographed, and the classification and identification of the system. The main findings are as follows: 1. Belonging to 51 genera and 200 species (including varieties) of diatoms were identified from all kinds of marine aquaculture waters, including a new record species (transparent the the sickle algae Falcula hyalina Takano,). Diatoms belonging to 33 genera were identified in samples of shrimp farming area 138 (including variants); cage culture area of ??the samples, the identification of diatoms 42 genera, 101 species (including varieties); in kelp farming area samples identified to diatoms 21 genera and 42 species (including varieties); identification of diatoms in the samples of shellfish farming area 31 genera and 54 species (including varieties). The most common diatoms in marine aquaculture waters samples Navicula genus (Navicula), the needle bar algae is (Synedra), the Chaetoceros genus (Chaetoceros), the bone costatum case (Skelenema). Largest number of species Nitzschia genus (Nitzschia), of 25, 12.5% ??of the total number of species, followed by Navicula genus (15 species), and double-wall algae genera (Diploneis) (13 species), twill algae belong (Pleurosigma) (13 species) accounted for 7.6% and 6.5% of the number of species. Scallop farming area Zhangzidao samples in November 2004, Chaetoceros as the main advantage is weak Chaetoceros (C.debilis) dominant (69.8%). Diatoms average cell density of 6.8 × 10 ~ 3cells / L, larger the inshore waters farming density, diatom biomass sample, richness and dominance index showed emerged inshore infralittoral trend, and diverse and evenness index opposite. Samples dinoflagellates appear in each of the stations have accounted for 5.7% of the total cell density. 3 November 2003 to May 2004, during the sampling period, the Quanzhou Bay shrimp pond seasonal changes in water temperature in the East China Sea obvious changes in the range of 12.8 ~~ 27.5 ° C Salinity ranges from 16 to 20. Winter relatively high salinity, 20 ‰. With the rise of the water temperature, the salinity decreased slightly. Nutrient concentrations shows in spring and autumn high nutrient concentrations, the lower trend in winter. From a number of species, diatom Nitzschia, Navicula dominant groups, respectively, accounted for 16.9% and 8.4% of the total number of species of diatoms. Cyclotella genus (Cyclotella), the Thalassiosira pseudonana case (Thalassiosira), the Skeletonema costatum the are (Skeletonema) Nanodiatoms exist in most months have. The dinoflagellate Prorocentrum genus (Prorocentrum) the dominant groups. In the of 12,1 month of cells number up to 10 ~ 7 ~ 10 ~ 8cells / L, accounting for 23% and 42.3% of the total phytoplankton cell number. During the same period the number of Nanodiatoms surge tiny small Cyclotella (Cyclotellacaspia), 6.36 ± 10 ~ 8cells / L, and the number of other types of value only 10 to 2 ~~ of 10 4 cells / L, and type less. The crescent Jane column algae (Cylindrotheca closterium), tiny Cyclotella, narrow the Amphora (Amphoraangusta), diamond-shaped algae is the main dominant species (or genus), the percentage of the total cell number in the phytoplankton community of up to 34.8% on average. 4 April 2004 to February 2005 with Ann's Bay the Xike cage aquaculture waters samples diatom nitzschia (13), twill algae (11) as the dominant populations, respectively, the total number of species 12.9 % and 5.9%. Chaetoceros case, the the round sieve algae are the average number of species reached 6-7. Crescent tube column algae the wavy stone silk the algae (Lithodesmium undulatum) nitzschia genus, and Amphora genus (Amphora), Navicula is a species were encountered in most of the month. Chaetoceros dominant on the number of species and the number of cells, is the dominant species Xike cage culture waters significantly. More Skeletonema costatum (Skeletonemacostatum), the distribution of the whole year is not, but in the cell number 8,10 month surge to three orders of magnitude higher than in winter, to 10 5 cells / L. Samples in the spring and summer, individual nitzschia clustered nitzschia (Nitzschia fasciculate) Miscellaneous nitzschia (Nitzschia hybrida) dominant in the winter samples, such as piano's Nanodiatoms rhombus The the algal small the variants (Nitzschia panduriformis var.minor) and shield oval the tiny algae variant (Cocconeis scutellum var.parva) as the dominant species. 5 samples Sanggou Bay breeding waters, diatoms Thalassiosira pseudonana case (Thalassiosira) (9 species), round screen algal genus (6 species), the Chaetoceros genus (5 species) of the dominant species, which accounted for 13.9% of the total number of species, 9.2% and 7.7%, respectively. Root canal algae are (Rhizosolenia) the dominant cell number. Are distributed in three breeding area (seaweed, scallops, oysters) root canal algae belong the wedge the algae genus (Licmophora), Thalassiosira pseudonana is a tide diatom (Pseudo-nitzschiapungens), with slot Melosira (Melosira sulcata), short-angle bends algae (Eucampia zoodiacus) on the dominant species of the genus and species, but also the culture zone. Seaweed farming area of ??phytoplankton either in kind or in the number of cells is higher than the other two culture zones. The Jiaozhou Bay Bay Estuary, higher nutrient content rich nutrients can lead to some of the red tide organism fulminant proliferation. Appeared in the March 2005 samples of the Jiaozhou Bay shellfish aquaculture waters tide diatom red tide cell number of 2.7 × 10 7cells / L, dominant in the samples R17 # and 543 #, total cell The proportion of 97.9% and 90.1%, respectively. Bloom period, in addition to a large number of dinoflagellate cysts, few other diatom species number, cell number more or less evenly. The number of cysts in the # 316 Sample highest reached 4.7 × 10 ~ 3cells / L, an average of 2.3 × 10 ~ 3cells / L. 7. Daya Bay aquaculture history for a long time, a higher degree of eutrophication, in recent years several outbreaks of red tide dinoflagellates and diatoms. Breeding waters in Daya Bay in February 2004 samples appeared the wing root Siphonales original the variant (Rhizosolenia alata f.genuina) red tide, the number of cells up to 3.2 × 10 5 cells / L. Red tide samples, the majority of other diatom species for micro-species of diatom, Thalassiosira pseudonana up to six kinds, accounting for 24.0% of the total cell number of species. 8 different breeding waters the dominant species of diatoms are quite different. Dominant diatom species in shrimp culture ponds, narrow the Amphora (32.8%), small of Cyclotella (30.4%), crescent the cylinder column algae (23.7%), boat-shaped algae (11.3%); cage culture area in waters diatoms dominant species shield oval algae (38.6%), the piano's nitzschia (13.3%), multi-sticks Navicula (Navicula ramosissima) (7.3%), Rockwell Chaetoceros (Chaetoceroslauderi) (5.3% ), Star umbilical the circular sieve algae (Coscinodiscus asteromphalus) (5.2%);, weak in the scallop farming area Chaetoceros (69.6%) a dominant role. Seaweed farming area compared to the wing root Siphonales variant (of Rhizosolenia alata f.indica) (19.2%) in India, dull - witted Siphonales semi thorn variable the type (Rhizosolenia hebetataf.semispina) (20.5%), spikes Pseudo-nitzschia (15.4% ). 9. Diatoms most biological (cell density) and the types of seasonal changes are more obvious. The overall biomass showing the distribution trends of spring> autumn> summer> winter, also influenced by the farming area of ??environmental factors, different species adapt to different environments and rich in nutrients, often easy dominant species prominent blooms, interspecific The uneven distribution of community stability weakened. 10 of the species composition of the different types of aquaculture waters (<20 micron) Nanodiatoms Nanodiatoms and small diatoms (20-200 microns) the proportion of cell density. The results show that, the breeding waters Nanodiatoms type and cell density proportion larger than the small diatoms. On the species composition, the maximum number of the kelp the culture zones Nanodiatoms the types and number of species of scallop farming area at least, but the cell density and seaweed farming area close. , Shrimp ponds in the average cell density on cell density Nanodiatoms mainly dominant species of planktonic diatoms Skeletonema costatum (Skeletonema costatum) and tiny Cyclotella (C.caspia),. Cage culture Nanodiatoms is mainly benthic species, the dominant species Navicula, Nitzschia small variants and oval algae. Nanodiatoms on seasonal distribution, are distributed in all seasons. However, in the majority culture zones, autumn and winter phytoplankton dominant Nanodiatoms. 11 detailed description of marine aquaculture waters seven major diatoms dominant species external morphological structure and the emergence of the seasonal and geographical distribution. And describes the current has not been reported in the country, an adherent of the diatom: the sickle algal genus Falcula M.Voigt the case a new record types: transparent the the sickle algae Falculahyalina Takano,. The algae mainly attached to the outer surface of the marine copepods. The article describes in detail the characteristics of the genus and species classification, ecological habits and their distribution.
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