Marine nanoplanktonic diatoms have been frequently either underestimated or overlooked in phytoplankton investigations due to their small size （2-20μm）, which allows most of them to pass through a regular phytoplan...Marine nanoplanktonic diatoms have been frequently either underestimated or overlooked in phytoplankton investigations due to their small size （2-20μm）, which allows most of them to pass through a regular phytoplankton net of 70μm pore size. For nanoplanktonic diatom classification, water samples （each 2000 mL） were collected from several representative sea areas of Chinese coast from May 2002 to May 2006. Pelagodictyon Clarke was identified as a newly recorded nanodiatom genus for China under transmission electron microscope （TEM）. This genus is characterized by the delicate structure of the valve face. The striae are seen to be formed by ribs with cross-ribs （frets） and the intervening spaces are occupied by polygonal cribra situated much close to the exterior face of the valve. Just one species was found, i.e., P. tenue Clarke. Detailed description of the taxonomic characteristics with TEM photographs of this species and its ecological habitat and distribution are given in this paper. Morphological characteristics comparisons among several resembling genera were discussed.展开更多
For the first time, nanodiatoms (<20μm) and microdiatoms (>20μm) in the coastal waters of Xiamen, Shandu, Fuqing, Haitan, Putian and Meizhou of Fujian Province along the western coast of the Taiwan Strait are ...For the first time, nanodiatoms (<20μm) and microdiatoms (>20μm) in the coastal waters of Xiamen, Shandu, Fuqing, Haitan, Putian and Meizhou of Fujian Province along the western coast of the Taiwan Strait are quantitatively counted by TEM in the paper. The results show that the number of nanodiatoms from all the station is more than that of microdiatoms, accounting for 92% of the species collected. This indicates that nanodiatoms constitute a large microcosm of the whole diatom group. Unfortunately, the lower resolution of light microscopes which have been used in the study of diatoms in the past makes this unneglectable microcosm unnoticed. Thanks to TEM, 47 species of nanodiatoms are identified and four of them are for the first time recorded in China. The new records are Hantzschia spectabilis, Navicula crucigera, Nav. spicula andNitzs. rosenstockii. The positive correlation between the contents of chlorophyll a and diatom cell number in the waters of Xiamen Harbour, which were determined simultaneously, shows that the variation of chlorophyll a content in the waters reflects, on the whole, the change of diatom number. In addition, the successful culture of nanodiatoms in the studies provides alternatives for the screening of high quality aquaculture feed.展开更多
基金supported by the National Natural Science Foundation of China (No.40627001,40476055)the Major State Basic Research Development Program of China (973Pro-gram) (No.2005CB422305)the Special Prophase Project of Fujian Science and Technology Major Program (2005YZ1024)
文摘Marine nanoplanktonic diatoms have been frequently either underestimated or overlooked in phytoplankton investigations due to their small size （2-20μm）, which allows most of them to pass through a regular phytoplankton net of 70μm pore size. For nanoplanktonic diatom classification, water samples （each 2000 mL） were collected from several representative sea areas of Chinese coast from May 2002 to May 2006. Pelagodictyon Clarke was identified as a newly recorded nanodiatom genus for China under transmission electron microscope （TEM）. This genus is characterized by the delicate structure of the valve face. The striae are seen to be formed by ribs with cross-ribs （frets） and the intervening spaces are occupied by polygonal cribra situated much close to the exterior face of the valve. Just one species was found, i.e., P. tenue Clarke. Detailed description of the taxonomic characteristics with TEM photographs of this species and its ecological habitat and distribution are given in this paper. Morphological characteristics comparisons among several resembling genera were discussed.
文摘For the first time, nanodiatoms (<20μm) and microdiatoms (>20μm) in the coastal waters of Xiamen, Shandu, Fuqing, Haitan, Putian and Meizhou of Fujian Province along the western coast of the Taiwan Strait are quantitatively counted by TEM in the paper. The results show that the number of nanodiatoms from all the station is more than that of microdiatoms, accounting for 92% of the species collected. This indicates that nanodiatoms constitute a large microcosm of the whole diatom group. Unfortunately, the lower resolution of light microscopes which have been used in the study of diatoms in the past makes this unneglectable microcosm unnoticed. Thanks to TEM, 47 species of nanodiatoms are identified and four of them are for the first time recorded in China. The new records are Hantzschia spectabilis, Navicula crucigera, Nav. spicula andNitzs. rosenstockii. The positive correlation between the contents of chlorophyll a and diatom cell number in the waters of Xiamen Harbour, which were determined simultaneously, shows that the variation of chlorophyll a content in the waters reflects, on the whole, the change of diatom number. In addition, the successful culture of nanodiatoms in the studies provides alternatives for the screening of high quality aquaculture feed.
