[Main factors influencing the growth of planktonic bacteria in fish pond ecosystem].
Focused on the main factors influencing the growth of bacteria in fish pond ecosystem, the variation of abundance in bacterial culture, the effects of substrate on bacterial growth, nutrient uptake and mineralization, the effects of bacterivorous predator and water temperature on bacterial growth were investigated in this paper. The results showed that the growth of bacteria and its uptake of C and N were enhanced by application of inorganic phosphorus into the water, but not by application of organic carbon and nitrogen, and that the N mineralization was increased by adding organic nitrogen, indicating that the bacterial growth was limited by inorganic P in the substrate, not by organic C and N. Among the five test groups, predator bacteria had the slowest growth rate, being lower than the control by 6.26-15.4%. The abundance of bacteria, its number increment and growth rate in the fish pond were found to be positively correlated with water temperature in different seasons. In addition, at higher temperature, the positive effects of nutrient application on bacterial growth were enhanced, while the negative effects of predator bacteria on bacterial growth were weakened.
Tan
Hongxin
H
Aquaculture College, Shanghai Fisheries University, Shanghai 200090. hxtan@shfu.edu.cn
Hu
Yuang
Y
Mei
Zhiping
Z
D000818:Animals; D001419:Bacteria / Q000254:growth & development*; D017753:Ecosystem; D005399:Fishes / Q000502:physiology*; D020387:Food Chain; D013696:Temperature; D014871:Water Microbiology