溶解作用对南海北部沉积物捕获器碳、氮通量估算的影响

Underestimation of C and N flux in the northern South China Sea due to dissolution in sediment trap samples

由于化学溶出、物理溶解以及胞外酶等作用,沉积物捕获器中颗粒物在锚系布放期间会发生一定程度的溶解,从而引起沉积物捕获器中碳、氮颗粒物通量的低估。本文对于1987—1988年南海北部中深层沉积物捕获器中碳、氮颗粒物的溶解作用进行了研究。溶解作用对于碳、氮通量估算的影响大致随着深度的增加而减小。总体而言,颗粒有机碳通量低估约3.8%~40.3%,平均值为26.6%。颗粒氮通量低估约4.2%~76.4%,平均值为43.7%。碳、氮颗粒物的溶出量与颗粒物通量大小关系不明显,但是样品储存时间对于碳、氮颗粒物溶解作用的影响较显著,储存时间较长的样品中颗粒物溶出量更大。

The sinking particles in the sediment trap can be dissolved to a certain extent due to the chemical dissolution,physical dissolution,extracellular enzyme,etc.This paper studies the dissolution of biogenic particles in the sediment trap located in the deep northern South China Sea in 1987-1988.It could be concluded that the effect of dissolution on the estimation of various fluxes decreased with depth.Overall,the underestimation of particulate organic carbon flux was about 3.8%-40.3%,with an average of 26.6%.The underestimation of particulate nitrogen flux was about 4.2%-76.4%,with an average of 43.7%.There were no relationships between the particle fluxes and the dissolved C and N.But the storing time had significant impact on dissolution of the sinking particles.The sample with longer storing time would have more dissolved quantity.