【摘要】 <正> 河口滨海区的水体是由组成和性质显著不同的河水和海水混合而成的。在河口区河水和海水的混合作用是复杂的动力学过程。在这一过程中还伴随着其他化学过程、物理化学过程和地质过程。诸如由于水质条件的剧变所引起的难溶物的沉淀作用,胶体和悬浮物的聚沉作用,各种固相与溶解成份之间的交换吸附与沉积作用以及气体交换作用等。因此,河口区混合水体所含物质的组成不仅与河水和海水的化学组成以及江河流量、涌入河口的海水量、河口的地形地貌、沿岸的地质、潮汐过程和气象等外界环境条件有关,也与伴随着混合过程而产生的许多复杂的化学、物理化学过程密切相关。这些过程尤其对混合水体中的微量元素的迁移及溶解气体的分布变化有显著的影响。更多还原

【Abstract】 According to the data observed on C1‰, SO4-, A1K, Mg+ + ,Na+ + K+ (calculated value) as well as pH in the Jinjiang River Estuary for two years or so, the characteristics of the distribution and variation of the relative composition of major hydrochemical constituents in the tidal estuaries are discussed and summarized in present paper.The ratios of all the major constituents to chlorinity in the Jinjiang River Estuary is increasing with the mixing coefficient (γ) .The rate of increase in theratio of each major constituent to enlorinity(AAA I/Cl ) in the dry season is greaterthan that in the flood period. Since the values observed on the rate of increase in the ratio of each major constituent to chlorinity well agree with the values calculated by the formula--wich is derived from the mixting equation, it is concluded that the simple mecha-nical mixing of seawater with river water is a fundamental factor which influences the relative composition of the major constituents in the estuaries.The authors put forward the concept "critical chlorinity" (Clk) of the rate of increase of each major constituent to chlorinity, with which the extent of influence by river on the relative composition of the major constituents can be estimated quantitatively.Finally, according to the observed data of the chlorinity and salinity in the Jinjiang River Estuary, an empirical formula relating chlorinity to salinityS=0. 032 + 1. 807Cl has been derived, which can he used under yarious hydrographic conditions.The salinity equations of Knudsen or Wooster et al. can’t be used under the Jinjiang River Estuary conditions; However, if the allowed absolute deviation of the calculated salinity is enlarged to ±0.04‰, then Knudsen ’s equation can still be used.Even if the estuaries, have excellent interchange with open sea water (or if the coastal waters are diluted by river water) , it is necessary to use a relevant equation relating salinity to chlorinity, because of the influence of river water on the estuary waters.更多还原