温度对两种蓝藻种间竞争的影响

Effects of temperature on interspecific competition between two blue-green algae

通过室内实验研究了不同温度条件下主要水华藻类——铜绿微囊藻(Microcystis aeruginisa)和巨颤藻(Oscillatoria princeps)的生长和种间竞争。结果表明:无论在纯培养体系还是混合培养体系中,微囊藻在25℃下生长最好,颤藻在30℃下生长最好;温度对藻类的种间竞争抑制参数能够产生明显影响,在20℃、25℃、30℃3个温度下,颤藻对微囊藻的竞争抑制参数随温度的升高而升高,30℃时颤藻对微囊藻的竞争抑制参数分别是20℃和25℃时的1.42倍和1.13倍,微囊藻对颤藻的竞争抑制参数则表现为25℃>30℃>20℃,25℃时微囊藻对颤藻的竞争抑制参数分别是20℃和30℃时的1.54倍和1.21倍,在20℃、25℃、30℃3个温度下,微囊藻对颤藻的竞争抑制参数均大于颤藻对微囊藻的竞争抑制参数,说明在各试验温度下,微囊藻对颤藻的抑制能力均大于颤藻对微囊藻的抑制能力;根据Lotka-Volterra竞争模型中的两物种竞争结果可初步判断,20℃和25℃温度下,微囊藻在竞争中取胜,30℃下,微囊藻和颤藻可以实现不稳定共存。

A laboratory experiment was conducted to study the interspecific competition between Microcystis aeruginosa and Oscillatoria princeps at 20 ℃,25 ℃,and 30 ℃.Both in pure culture and in mixed culture,M.aeruginosa grew best at 25 ℃,while O.princeps grew best at 30 ℃.Temperature had obvious effects on the inhibition parameter of interspecific competition between the two algae.The inhibition parameter of O.princeps against M.aeruginosa at 30 ℃ was 1.42 and 1.13 times as that at 20 ℃ and 25 ℃,while the inhibition parameter of M.aeruginosa against O.princeps was the maximum at 25 ℃,being 1.54 and 1.21 times as that at 20 ℃ and 30 ℃,respectively.At 20 ℃,25 ℃,and 30 ℃,the inhibition parameter of M.aeruginosa against O.princeps was all larger than that of O.princeps against M.aeruginosa,which meant the stronger inhibition effects of M.aeruginosa on O.princeps at the test temperatures.Based on the competition model of Lotka-Volterra,M.aeruginosa won the competition at 20 ℃ and 25 ℃,and M.aeruginosa and O.princeps could unstably coexist at 30 ℃.