Mixed Tracer Injection Method to Measure Reaeration Coefficients in Small Streams
Mixed Tracer Injection Method to Measure Reaeration Coefficients in Small Streams
复制标题
混合示踪剂注入法测量小流中的反应系数
DOI：
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发表时间：
2012
期刊：
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通讯作者：
G. Kipphut
中科院分区：
文献类型：
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作者：
Hwaseong Jin;D. White;J. Ramsey;G. Kipphut
复氧系数(K)，即大气和水面之间的氧气交换速率，是了解水质损害和溪流代谢的重要参数。我们对丙烷喷射法进行了改进，以测量气体交换系数，并对其在小蒸气中的应用进行了评价。示踪剂溶液是通过将丙烷直接溶解在保守的溶质溶液中而制备的，并以恒速进样、单段塞或加长段塞的形式注入。在示踪剂浓度峰值时，在研究河段沿线的4至5个采样点采集水样，并测量丙烷和电导率。丙烷交换率(k丙烷)是用丙烷/电导率与溶质移动时间的比值(小时)的回归方法计算的。混合示踪剂注射法在四条溪流中进行，所有K丙烷测量(n = 8)均有统计学意义(p <； 0.0 5)。持续时间短的恒速注入和延长的段塞式注入提供了比单一段塞式注入更高的R2。用丙烷注入测得的k20在−1每天5.4%到40.0%之间，它们与经验估计的k值显著相关。与丙烷混合示踪剂注入方法可能会减少现场时间、人员需求和现场设备；因此，它可能会降低气体交换系数测量的总体成本，是一种在小而偏远的溪流中有效的方法。
Reaeration coefficient (k), the rate of oxygen exchange between the atmosphere and water surface, is an important parameter for understanding water quality impairment and stream metabolism. We modified the propane injection method to measure gas exchange coefficients and evaluated its application for small streams. The tracer solution was prepared by solubilizing propane directly in a conservative solute solution, and it was injected as a constant-rate injection, a single slug, or an extended slug. Water samples were taken at four to five sampling stations along the study reach at the tracer concentration peak, and propane and conductivity were measured. The propane exchange rate (kpropane) was calculated using the regression method with the propane/conductivity ratio against solute travel time (in hours). The mixed tracer injection method was conducted in four streams, and all kpropane measurements (n = 8) were statistically significant (p < 0.05). The short-duration constant rate injection and extended slug injection provided kpropane estimates with higher r2 than the single slug injection. The k20 measured with propane injection ranged from 5.4 to 40.0 day−1, and they were significantly correlated with empirically estimated k. The mixed tracer injection method with propane could potentially reduce field time, crew demands, and field equipment; thus, it would potentially lower the overall cost of gas exchange coefficient measurements and be an effective method in small, remote streams.