摘要
利用连续提取分级的方法定量分析阳宗海表层沉积物磷赋存形态,阐明了沉积物C、N、H和O组成及溶解有机质(DOM)紫外-可见光谱特征,探讨沉积物元素组成及DOM组成结构对不同形态磷含量的影响.结果表明:(1)沉积物潜在可移动磷含量在68.67~124.70 mg/kg之间变化,平均占总磷含量的9.81%,表现为BD-P>Na OH-nr P>NH_4Cl-P;沉积物稳定磷含量在496.73~908.28 mg/kg之间变化,平均占总磷含量的60.86%.(2)沉积物C、N含量和疏水性DOM光谱参数A_(240-400)表现出北部高、南部低的变化趋势,但H/C、O/C和(N+O)/C摩尔比和亲水性DOM光谱参数A_(240-400)变化趋势则与之恰好相反.(3)沉积物NH4Cl-P含量与C、N和H含量之间呈显著正相关,但与H/C、O/C、(N+O)/C摩尔比和亲水性DOM光谱参数E_2/E_3值之间呈显著负相关;NaOH-rP和BD-P+NaOH-rP含量均与O含量及O/H摩尔比呈显著负相关;NaOH-rP、BD-P+NaOH-rP和HCl-P均与疏水性DOM光谱参数A_(240-400)值之间呈显著正相关.因此,天然有机质元素组成及官能团结构是影响沉积物磷赋存形态的重要因素.
Characteristics of phosphorus fractions in surface sediments of the Lake Yangzonghai were studied applying the method of continuous extraction and classification. The element composition of C, N, H and O, UV-vis spectrum features of hydrophobic and hydrophilic dissolved organic matter （DOM）, and their effects on P fractions in sediments were also clarified.The results indicated that the mobile-P contents in sediment ranged in 68.67-124.70 mg/kg and accounted for 9.81% of total phosphorus on average. The immobile-P contents in sediment ranged in 496.73-908.28 mg/kg, accounting for 60.86% of total phosphorus on average. The contents of different P forms decreased from north to south part, and the immobile-P content was significantly higher than that of mobile-P, indicating P retention in sediments. The contents of C, N and UV-vis spectrum integral area （ A240_40o） of hydrophific DOM showed a decreasing trend from north to south of the lake, while the ratios of H/C, O/C, （ O＋N）/C and the A24o 4oovalue of hydrophobic DOM presented a reversing trend. Significantly positive correlations were found between NH4 C1-P and C, N and H contents, and the negative correlations were found between NH4C1-P contents and H/C, O/C, （N＋O）/C, UV-vis spectrum eigenratio （Ez/E3 ） of hydrophilic DOM. In addition, NaOH-rP and BD-P＋NaOH-rP have negative correlations with the O and O/H ratios, but all of the NaOH-rP, BD-P＋NaOH-rP and HCl-P contents in sediments have positive correlations with the A240-400 valueof hydrophobic DOM. Therefore, element composition and functional groups structure of nature organic matter is the important fac- tors influencing the P fractions.
出处
《湖泊科学》
EI
CAS
CSCD
北大核心
2017年第2期308-316,共9页
Journal of Lake Sciences
基金
云南省科技创新人才计划(2015HC018)项目资助
关键词
阳宗海
沉积物
元素组成
溶解有机质
磷形态
Lake Yangzonghai
sediment
elements composition
dissolved organic matter
phosphorus fractions
