%0 Journal Article %T 环境胁迫对水生植物根系分泌小分子量有机酸(LMWOAs)影响特征 %T Effects of Environmental Stress on Characteristics of Low Molecular Weight Organic Acids Secreted by Macrophyte Roots %A 张治宏 %A 杨诗卡 %A 韩超 %A 许笛 %A 王兆德 %A 柯凡 %A 申秋实 %A ZHANG,Zhihong %A YANG,Shika %A HAN,Chao %A XU,Di %A WANG,Zhaode %A KE,Fan %A SHEN,Qiushi %J 湖泊科学 %J Journal of Lake Sciences %@ 1003-5427 %V %N %D %P - %K 根系分泌物;小分子量有机酸;水生植物;环境胁迫 %K root exudation; LMWOAs; aquatic macrophyte; environmental stress %X 本文首次对马来眼子菜 (Potamogeton malaianus)、苦草 (Vallisneria natans)、芦苇 (Phragmites australis)、菖蒲 (Acorus calamus)、荇菜 (Nymphoides peltatum)和菱角 (Trapa manshurica) 6种水生植物根系小分子量有机酸(Low Molecular Weight Organic Acids, LMWOAs)分泌差异性及其对环境胁迫(温度、缺磷和高氨氮)响应特征进行研究。结果证实 6种受试植物根系分泌LMWOAs组成和含量具有明显的物种差异性;其中,甲酸、乳酸和草酸为主要有机酸。温度可显著影响水生植物根系LMWOAs分泌量而对种类影响不大,高温(30℃)刺激荇菜根系LMWOAs分泌量增加, 但却明显抑制苦草和菖蒲根系LMWOAs分泌; 25 ℃时马来眼子菜、芦苇和菱角根系LMWOAs分泌量最多。缺磷和高氨氮胁迫均会显著影响水生植物根系LMWOAs分泌量和种类。缺磷胁迫促进苦草、菖蒲和荇菜根系LMWOAs分泌量增加68.68%, 55.30%和257.82%,并刺激乙酸和苹果酸等新增有机酸分泌;而缺磷胁迫抑制马来眼子菜、芦苇和菱角根系LMWOAs分泌量降低38.72%, 13.79%和58.99%, 且乳酸、甲酸和丁二酸分泌完全被抑制;这表明苦草、菖蒲和荇菜三者能较好的适应缺磷环境。高氨氮胁迫下苦草根系LWMOAs分泌量和种类增加明显;而其余5种受试植物在高氨氮胁迫下根系LMWOAs分泌量被明显抑制,尤其是乳酸、苹果酸和酒石酸含量显著降低。综上所述,水生植物分泌LMWOAs特征差异性显著,可在一定程度上反映其耐逆境胁迫能力,本文结果将为水生植物生态修复机理和实践提供重要理论依据。 %X In this work, six typical aquatic macrophytes of Potamogeton malaianus、Vallisneria natans、Phragmites australis、Acorus calamus、Nymphoides peltatum and Trapa manshurica were firstly selected to investigate their root secretion characteristics of low molecular weight organic acids (LWMOAs) under the stresses of temperature, phosphorus (P) deficiency and high level of ammonia-nitrogen (NH4+-N). Generally, the compositions and amounts of LMWOAs significantly varied among six species, and formic acid, lactic acid and oxalic acid were the dominate LWMOAs. Temperature didn’t changed the LWMOAs compositions but had significantly effect on LWMOAs amounts. Higher temperature (30 ℃) was demonstrated to promote LMWOAs secretions for N. peltatum but evidently inhabit that of V. natans and A. calamus. The highest LMWOAs secretion of P. malaianus, P. australis and T. manshurica was at 25℃. P deficiency and high level of NH4+-N could significantly affect the compositions and amounts of LWMOAs. Under P-deficiency stress, the LMWOAs amounts secreted by V. natans, A. calamus and N. peltatum were increased by 68.68%, 55.30% and 257.82% respectively, and the acetic acid and malic acid were newly secreted. In contrast, the LMWOAs amounts secreted by P. malaianus, P. australis and T. manshurica were significantly reduced by 8.72%, 13.79% and 58.99% respectively, and the lactic acid, formic and succinic acid were completely inhibited. It indicated that V. natans, A. calamus and N. peltatum were more adaptive to low P sediment. Except for V. natans, high level of NH4+-N significantly reduced the amounts of LWMOAs, especially lactic acid, malic acid and tartaric acid for the investigated species. In conclusion, significant differences among LMWOAs secreted by macrophytes are closely associated with their tolerances to environmental stress, which will provide important scientific supports in the field of aquatic ecosystem restoration. %R %U http://www.jlakes.org/ch/reader/view_abstract.aspx %1 JIS Version 3.0.0