小浪底水库水沙调控影响下的黄河POC输送特征研究

于2011年11月—2012年10月在黄河小浪底站和花园口站进行连续采样观测并结合同期水文资料,研究了在小浪底水库水沙调控影响下黄河颗粒有机碳(POC)的输送规律.结果表明,在小浪底水库正常调度期间,小浪底站和花园口站POC含量分别为0.37~0.65 mg·L-1和1.88~6.47 mg·L-1,小浪底站POC含量明显低于同期的花园口站.在小浪底水库调水调沙期间,小浪底站和花园口站的POC含量分别为0.43~693.75 mg·L-1和6.97~210.65 mg·L-1,在水库泄水阶段小浪底站POC含量明显低于花园口站,而在水库排沙阶段小浪底站POC含量又明显高于花园口站.小浪底站和花园口站全年POC输送量分别为53.2万t和49.2万t,其中,7—8月POC输送量最多,小浪底站7—8月POC输送量占全年POC输送量的97.5%,花园口站7—8月POC输送量占全年POC输送量的78.2%.小浪底水库"水沙调控"对黄河POC输送的影响明显不同于其他河流上的水库,它不仅拦蓄上游输送的POC,而在特定时间又将拦蓄水库中的POC大量排出水库.

Study on POC transport characteristics in Yellow River impacted by runoff and sediment control of the Xiaolangdi reservoir

Transport characteristics of Particulate Organic Carbon (POC) impacted by runoff and sediment control in Xiaolangdi Reservoir was studied by the combination of continuous sampling observation results with contemporaneous hydrologic data in Xiaolangdi station and Huayuankou station from November 2011 to October 2012. The results demonstrated that POC contents of Xiaolangdi station were obviously lower than that of Huayuankou station during the same period, with the concentrations being 0.37~0.65 mg · L^-1 and 1.88~6.47 mg · L^-1, respectively. During water and sediment regulation period, POC contents in Xiaolangdi station and Huayuankou station were 0.43~693.75 mg · L^-1 and 6.97~210.65 mg · L^-1, respectively. The POC content in Xiaolangdi station was significantly lower than that in Huayuankou station in drainage period, while POC content in Xiaolangdi station was obviously higher than that in Huayuankou station during sediment flushing period. Annual fluxes of POC from Xiaolangdi station and Huayuankou station were 531.9 and 492.1 thousand tons, and POC flux were the most between July and August. POC fluxes in these two stations between July and August occupied 97.5% and 78.2% of annual POC fluxes, respectively. POC transport affected by "water and sediment regulation" of Xiaolangdi reservoir in the Yellow River was significantly different from that by other rivers reservoirs. Therefore, Xiaoliangdi reservoir not only retained POC from the upstream, but also released POC from the Xiaoliangdi reservoir at a particular time.