黄河干流有机碳的时空分布特征

Temporal and Spatial Distributions of Organic Carbon in the Huanghe(Yellow) River

通过2003—2009年多个航次对黄河干流DOC（溶解有机碳）和POC（颗粒有机碳））及相关参数的调查研究,结果表明：TSS（颗粒悬浮物）为91.42~8188 mg/L,POC为0.65~24.20 mg/L,POC%（POC/TSS×100%）为0.44%~2.21%,DOC为1.57~4.77 mg/L,有机碳沿程分布具有明显的空间特征。花园口水文年调查中有机碳含量与流量的季节变化密切相关,POC主要受冲刷影响,而DOC在不同季节分别体现出冲刷、稀释或浓缩效应。修建水库和调水调沙这2个显著的人为干扰活动对黄河有机碳的性质及输运产生了截然不同的影响：库区自生源对有机碳的贡献明显大于干流,DOC/POC为6.64~12.00,DOC是有机碳的主要形式,同时水库截流,颗粒物沉降降低了颗粒有机碳的输运量,而调水调沙却加强了有机碳的输运,该时期DOC/POC为0.01~0.47,POC是有机碳输运的主导形态。

We examined organic carbon（particulate and dissolved） throughout the main stream of the Huanghe River from 2003 to 2009.The river is characterized by TSS（total suspended substances）,POC and DOC concentrations of 91.42～8188,0.65～24.20 and 1.57～4.77 mg/L,and POC%（POC content in TSS） of 0.44%～2.21%,respectively.The seasonal distributions of organic carbon are strongly connected with discharge： POC is mainly influenced by erosion with runoff and DOC is affected by flush effect or dilution in different seasons.Compared with the main stream of the river,phytoplankton contributed much more to organic carbon in the reservoirs where DOC/POC varied from 6.64 to 12.00,indicating that organic carbon is dominated by DOC.Substantial POC load is retained in the reservoirs due to precipitation.However,considerable amount of organic carbon would be exported during the SW period when POC is the main form in organic carbon with DOC/POC value between 0.01～0.47.