CAJ | 학술논문

咸潮只是河口偏于向陆一侧盐度较低（0.5~10）的那一部分盐淡混合或冲淡水体，不宜将河口“咸水”和海洋“盐水”等同或混为一谈；视“咸潮上溯”为“盐水入侵”欠当。咸潮上溯为河口自身物质的随潮运动，基本上是一种被动的行为。咸潮上溯之动力机理，与河口水、盐物质于一年、一月和一天中随潮在河口的进出、“排”“蓄”循环运动过程有关。小潮向中潮变化时期（一月中）及其初落时段（一天中），河口正处于由“蓄”（进）转“排”（出）阶段，其时表“排”（淡水）、底“蓄”（咸水），水体高度呈层，受异重流的影响，底部咸潮进一步上溯“冲刺”达盐度最大值。大潮向中潮变化时的压咸效果最佳。
함조지시하구편우향륙일측염도교저（0.5~10）적나일부분염담혼합혹충담수체，불의장하구“함수”화해양“염수”등동혹혼위일담；시“함조상소”위“염수입침”흠당。함조상소위하구자신물질적수조운동，기본상시일충피동적행위。함조상소지동력궤리，여하구수、염물질우일년、일월화일천중수조재하구적진출、“배”“축”순배운동과정유관。소조향중조변화시기（일월중）급기초락시단（일천중），하구정처우유“축”（진）전“배”（출）계단，기시표“배”（담수）、저“축”（함수），수체고도정층，수이중류적영향，저부함조진일보상소“충자”체염도최대치。대조향중조변화시적압함효과최가。
Salt tide is designated as the low salinity (0.5-10) water body mixing salty and fresh water on landward side of the estuary. The estuary “salt water” and oceans “brine” should not be equivalent or confused. It is inappropriate to take“salt tide tracing”as“saltwater intrusion”. The salt tide tracing upstream is that the estuarine material moves with the tide movement, that is essentially a passive act. The dynamic mechanism of salt tide tracing is relevant to the circular motion process that estuarine water and salt substance move in and out with the tide, or drain and retain in a month or a day. During the period from neap tide to moderate tide (in a month ) and that at the beginning of tide ebb (in a day), estuary is in the phase from retaining (moving in) to draining (moving out). Freshwater drains at surface layer, while salt water at bottom layer, forming an obvious stratification structure. Affected by the density current, salt tide at the bottom further traces upstream rapidly, and its salinity reaches the maximum. Best result can be achieved for lowering the salinity when spring tide is transforming into moderate.