La、N、P对浮萍色素的影响及浮萍吸收N、P能力初探

研究不同浓度的镧(La2O3)、氮(N)、磷(P)单因素溶液培养条件下,浮萍色素含量变化及浮萍对水体中N、P吸收的能力.结果表明,ρ(N)和ρ(P)分别为20和8 mg/L时,浮萍色素含量达到峰值;不同浓度La溶液培养下的浮萍色素含量均显著低于对照,ρ(La)为10 mg/L即对浮萍色素含量的增加产生抑制.培养时间(3～15 d)对浮萍色素含量的影响因培养条件不同而异,其中不同浓度N、La培养条件下其影响显著,但在不同浓度P条件下其影响则不显著.浮萍(鲜重)对水体中N和P的吸收峰值分别约为5和0.5 mg/g,且对N和P吸收的能力随N和P浓度升高呈现增强的趋势.

Effects of La, N and P on Duckweed Growth and Duckweed Absorption Ability to N or P in Culture Solution

Studies on changes of pigments contents in duckweed(Spirodela polyrrihza) and its absorption ability to N and P in culture solution which contained separately lanthanum(La2O3),N or P with different concentration.The results showed that the highest pigment contents in duckweed were found at ρ(N) 20 mg/L in contained N solution and at ρ(P) 8 mg/L in contained P solution.The pigment contents in duckweed treated with La were observably reduced than those without any treatment(CK).Duckweed gowth may be inhibited above ρ(La) 10 mg/L.Effects of culturing time on the pigment contents were different,there were significant influence in contained N or La solutions with different concentration,and there were not in contained P solution.The highest N and P absorbed dose from the solution were 5 mg/g FW and 0.5 mg/g FW respectively,and the absorption ability of duckweed would be improved when N and P concentration were increased in solution.It was suggested that duckweed could absorb N and P from the culture solution during its gowth and these characters could be used to repair lake or water eutrophication.