采用梯度扩散薄膜(DGT)技术,以太湖9个采样点所采集的27个沉积物柱样为研究对象,研究沉积物中DGT所测量的磷浓度(DGT—P)与铜绿微囊藻生长量之间的关系,同时与4种常规的生物可利用性磷方法[(水溶性磷(WSP)、易解析磷(RDP)、藻可利用磷(AAP)和NaHCO3提取磷(Olsen-P))]进行比较。评价不同提取方法获得的太湖沉积物生物可利用性磷与铜绿微囊藻生长量的关系结果表明,DGT-P与藻生长量的相关系数为R^2=0.941(P〈0.01),高于4种生物可利用性磷提取法的相关系数(WSP,0.780、RDP,0.806、AAP,0.849、Olsen—P,0.910).结果表明DGT技术可以作为预测原位沉积物磷的生物可利用性的工具.
Diffusive gradients in thin-films (DGT) technique, four traditional extraction methods for bioavailable phosphorus (water soluble P, readily desorbable P, algal-available P and NaI-ICOaextractable P) and algal assay were compared to investigate availability of phosphorus (P) in sediments from 9 sampling sites in Lake Taihu to Microcystis aeruginosa. DGT-measured P (DGT-P) showed higher correlation (R^2 =0.941, P〈0.01) with algal growth than other traditional extraction methods for bioavailable phosphorus (R^2 =0.780, 0.806, 0.849 and 0.910 for WSP, RDP, AAP and Olsen-P, respectively, P〈0.01). Therefore, DGT technology could be considered as a good tool to assess bioavailability of phosphorus in sediments to algae.