白洋淀沟壕系统水陆交错区生物质磷形态特征研究

Morphological characteristics of biogenic phosphorus in aquatic-terrestrial ecotone of Baiyangdian

利用液相31P核磁共振的分析方法,研究了白洋淀水陆交错区中生物质磷(Biogenic-P)的形态特征.结果表明:不同类型水陆交错区磷含量差异较大,水陆交错区中间土壤总磷(TP)含量最高,为1342.81~2444.90 mg·kg^(-1);水陆交错区Biogenic-P含量为437.65~1309.20 mg·kg^(-1),占TP含量的25.62%~60.26%;使用液相31P-NMR技术共检测到7类磷化合物,其中,Biogenic-P共计检测到6种,包括磷酸单酯(Mono-P)、DNA磷(DNA-P)、焦磷酸盐(Pyro-P)、磷脂(Lipids-P)、多聚磷酸盐(Poly-P)和膦酸盐(Phon-P);水陆交错区Biogenic-P以Mono-P为主,含量为372.94~1086.96 mg·kg^(-1),TP含量平均值是全国土壤磷含量平均值的3.41倍;水陆交错区界面土壤与中间土壤相较沉积物和边缘土壤Biogenic-P含量更高;从水陆交错区的中间土壤到沉积物,Biogenic-P含量变化趋势与总有机质(OM)含量变化趋势相反.基于液相31P核磁共振技术,本文对白洋淀沟壕系统水陆交错区中Biogenic-P形态特征与分布提出了新的认识,有助于深入理解水陆交错区磷的生物地球化学循环过程,为流域磷输入的控制提供理论支撑.

The morphological characteristics of biogenic phosphorus(Biogenic-P) in aquatic-terrestrial ecotone of Baiyangdian were studied by solution phosphorus nuclear magnetic resonance(31P-NMR). The results showed that the phosphorus(P) concentration in aquatic-terrestrial ecotone varied greatly in different geographical regions, the highest total phosphorus(TP) concentration was found in the soil from the middle of aquatic-terrestrial ecotone, which ranged from 1342.81 to 2444.90 mg·kg^(-1). The content of biogenic-P in aquatic-terrestrial ecotone was between 437.65 to 1309.20 mg·kg^(-1), accounting for 25.62% to 60.26% of the TP content. Seven kinds of P compounds were detected in aquatic-terrestrial ecotone by 31P-NMR, among which, six kinds of P compounds were detected in biogenic-P including phosphate monoesters(Mono-P), deoxyribonucleic acid(DNA-P), pyrophosphate(Pyro-P), phospholipids(Lipids-P), polyphosphate(Poly-P) and phosphonates(Phon-P). Mono-P was the main component of biogenic-P in aquatic-terrestrial ecotone, with the concentration ranged from 372.94 to 1086.96 mg·kg^(-1). Biogenic-P was dominated by Mono-P in aquatic-terrestrial ecotone, with the concentration between 372.94 and 1086.96 mg·kg^(-1). The average TP concentration in aquatic-terrestrial ecotone was 3.41 times higher than the national average soil P content. The concentration of biogenic-P in the interface and intermediate soils in aquatic-terrestrial ecotone was higher than that in the sediment and marginal soil. From the soil in the interlaced area to the sediments in aquatic-terrestrial ecotone, the variations of biogenic-P concentration showed the opposite tendency compared with OM. Based on the solution 31P-NMR technology, this paper offers some new understanding on the morphological characteristics and distribution of biogenic-P in aquatic-terrestrial ecotone of the Baiyangdian, which will help to understand the phosphorus biogeochemical cycle process in aquatic-terrestrial ecotone and provide theoretical support for the control of phosphorus input to the basin.