Purpose of the current study was to investigate the effects of constantly wet and dried-rewetted sediments on root functional traits of emerged macrophytes and their nutrients removal abilities. It is based on the hypothesis that root characteristics and nutrients removal abilities of plants will be altered in the course of sediment desiccation. Four emerged macrophytes including two fibrous-root plants (Canna indica and Acorus calamus) and two thick-root plants (Alocasia cucullata and Aglaonema commutatum) were investigated for their root functional traits and rhizoperformance in both wet and dried-rewetted sediments. Results showed that sediment desiccation followed by rewetting substantially altered the root functional traits (root surface area, radial oxygen loss, and root activity) of plants due to adverse changes in morphological characteristics (porosity, bulk density, particle density) of dried-rewetted sediments than by wet sediments. Consequently, limited plants growth and removal of nitrogen (N), phosphorus (P) and dissolved organic carbon (DOC) were recorded in dried-rewetted sediments and their pore water than in wet sediments. Radial oxygen loss from plant roots correlated positively with root functional traits, plants growth, and removal of N, P and DOC from pore water and sediment in both sediment types. Among the macrophyte species, the fibrous-root plants having advantages root functional traits, greatly influenced the rhizospheric conditions (pH, dissolved oxygen and redox potential), and demonstrated higher N, P and DOC reduction from both sediment types. While, the thick-rooted plants with thick diameter roots (D > 1 mm) and higher rhizome exhibited longer life-span in both sediment types.

本研究的目的是研究不断湿润和再湿润的沉积物对出苗的大型植物根系功能性状及其营养去除能力的影响。基于这样的假设，在沉积物干燥过程中，植物的根系特征和养分去除能力会发生变化。出现了四种大型植物，包括两种纤维状根植物（印度Canna和A蒲）和两种浓密的根植物（Alocasia cucullata和Aglaonema commutatum））研究了它们在湿润和干润的沉积物中的根功能性状和根际性能。结果表明，由于干重新沉降的沉积物的形态特征（孔隙度，堆积密度，颗粒密度）的不利变化，沉积物干燥然后再润湿，从而显着改变了植物的根部功能性状（根部表面积，径向氧损失和根系活性）。而不是湿的沉积物。因此，干湿沉降的沉积物及其孔隙水中的植物生长和除氮（N），磷（P）和溶解的有机碳（DOC）的能力有限，而不是湿润的沉积物。植物根部的径向氧损失与根系功能性状，植物生长以及两种沉积物类型的孔隙水和沉积物中氮，磷和DOC的去除呈正相关。在大型植物物种中，纤维根植物具有良好的根部功能性状，极大地影响了根际条件（pH，溶解氧和氧化还原电势），并且从两种沉积物中均显示出更高的氮，磷和DOC含量降低。而粗壮的植物具有较粗的直径根（D > 1 mm）和较高的根茎在两种沉积物中都具有更长的寿命。