通过对分层小水库沉积物和上覆水温度剖面的7次监测,计算沉积物-水界面的热交换通量,探讨沉积物与水之间热量交换的时空变化特征.结果表明:沉积物-水界面热交换通量具有明显的季节变化,在春夏季库水升温分层以及秋季降温混合时期由库水向沉积物传递热量;冬季由沉积物向库水释放热量.浅水区水温的日变化促使沉积物-水热交换具有明显日变化特征.库区内由于水深不同,热交换特征也存在空间差异,与坝前相比,水库中心水深较浅,春季热交换方向转变的时间早;水库中心夏季由水传向沉积物的最大热通量 (106. 6 W/m2) 高于坝前深水区 (23. 8 W/m2) .夏季当水体透明度较高时,沉积物直接接受太阳辐射引起热交换方向改变为由沉积物向水传递.%Through seven monitoring of temperature profiles of sediment and overlying water in a small stratified reservoir, the heat exchange fluxes at the sediment-water interface were calculated, and the temporal and spatial characteristics of heat exchange between sediment and water were discussed. The results show that the heat exchange fluxes at the sediment-water interface have obvious seasonal variations. Heat transfers from reservoir water to sediment during the period of warming and stratification of reservoir water in spring and summer and cooling and mixing in autumn, and the heat releases from the sediment to the reservoir water in winter. The diurnal variation of water temperature in shallow water area leads to obvious diurnal variation of sediment-water heat exchange. Because of the different water depths, there are also spatial differences in heat exchange characteristics in the reservoir. The water depth in the reservoir center is shallower than that in the front of the dam, and the direction of heat exchange changes earlier in spring. The maximum heat flux from water to sediment in the reservoir center in summer (106. 6 W/m2) is higher than that in the front of the dam (23. 8 W/m2). When the transparency of water is high in summer, the heat exchange direction changes to be from sediment to water due to the direct acceptance of solar radiation.
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