不同施肥模式对克氏原螯虾稻田养殖水体浮游植物群落结构的影响

为探讨在克氏原螯虾(Procambarus clarkii)稻田养殖水体中施用不同肥料对浮游植物群落结构的影响,以湖北省荆州市太湖农场稻虾模式试验基地为场所,于2019年4—5月进行试验,设置施化肥、施有机肥和施有机-无机复混肥3个处理.每块稻田中克氏原螯虾的放养密度为2.30ind/m2.结果发现,施化肥、施有机肥和...

EFFECTS OF DIFFERENT FERTILIZATION PATTERNS ON PHYTOPLANKTON COMMUNITY STRUCTURE IN PADDY FIELDS WITH PROCAMBARUS CLARKII

The farming of freshwater crayfish Procambarus clarkii in paddy fields is a popular cultivation method, which can account for more than 80% of the annual crayfish production in China. To explore the effects of different fertilization patterns on phytoplankton community structure in paddy fields where P. clarkii were raised, experiments were carried out from April to May 2019 in Taihu Farm in Jingzhou City, Hubei Province. Three kinds of fertilizer, including chemical fertilizer (H), organic fertilizer (Y) and organic-inorganic compound fertilizer (X) were used in different paddy fields. P. clarkii was stocked in each paddy field with a density of 2.30 ind./m2. The results showed that 74, 81 and 81 species of phytoplankton were identified in H, Y and X treatments, respectively. The total abundance and total biomass of phytoplankton in H, Y and X treatments ranged from 0.78×106 to 30.32×106 ind./L and 0.55 to 26.00 mg/L, respectively. Both phytoplankton abundance and biomass followed the order H>X>Y. Chlorophyta and Cryptophyta were the most dominant groups, which resulted in the dynamics of phytoplankton community as the fluctuations of these two groups. The Pielou and Shannon-Wiener indexes were higher in Y and X treatments than those in H treatment. In addition, phytoplankton communities showed a more stable state in Y and X treatments than in H treatment. Phytoplankton community in paddy fields exhibited an apparent temporal trend, and water temperature and nutrients were the best drivers for phytoplankton abundance. These results demonstrate that the application of organic-inorganic compound fertilizer in paddy fields can facilitate the growth of phytoplankton and improve the community structure. It is better to apply the compound fertilizer than just one. Since fertilization plays an important role in paddy ecosystem environment, rice and crayfish cultivation, it is of great significance to explore the linkage between fertilization pattern and phytoplankton community in paddy fields.