三种湿地植物的生长及根系溶解性有机碳分泌物研究

Growth and Dissolved Organic Carbon Exudates from Roots of Three Wetland Plants

摘要:

研究了美人蕉(Canna indica Linn.)、风车草(Cyperus flabelliformis Rottb.)和水鬼蕉(Hymenocallis littoralis (Jack.) Salisb.) 3种湿地植物在人工气候室水培条件下的根系溶解性有机碳分泌物分泌量及其与生长的关系。结果表明,风车草和美人蕉的植株总生物量和根系生物量接近,根系溶解性有机分泌物分泌量也接近。水鬼蕉的总生物量和根系生物量显著低于风车草和美人蕉(P<0.01),根系溶解性有机分泌物分泌量也显著低于风车草和美人蕉(P<0.01)。但美人蕉、风车草和水鬼蕉根系单位质量的溶解性有机碳分泌物的分泌量接近,分别为4.21 mg g^-1d^-1、5.28 mg g^-1d^-1和4.03 mg g^-1d^-1。3种湿地植物的根系溶解性有机碳分泌物分泌量与植株总生物量和根系生物量均呈极显著的正相关(P<0.01)。

关键词:湿地植物;生物量;pH;根系;溶解性有机碳分泌物

Abstract:

Three wetland species, Canna indica Linn., Cyperus flabelliformis Rottb., and Hymenocallis littoralis (Jack.) Salisb., were grown in solution culture systems in a climate chamber, and the growth characteristics and dissolved organic carbon exudates (DOC) of roots were studied. The results showed that Canna indica and Cyperus flabelliformis had similar total biomass and root biomass, and similar amount of DOC, which were significantly higher than those of H. littoralis (P<0.01). However, production of DOC per unit root biomass was similar for the three species. DOC of the three wetland plants were positively correlated with total biomass (P<0.01) and root biomass (P<0.01).

Key words:Wetland plant;Biomass;pH;Root system;Dissolved organic carbon exudates