闽江口水下三角洲的形成与演变全文从分析控制或影响闽江口水下三角洲发育的环境因素入手，探讨了闽江口水下三角洲的地貌特征、成因及演变。研究结果表明，闽江口水下三角洲属于构造—潮控型三角洲，其地貌特征和成因与典型的潮成三角洲既有共同点，也存在着较大的差异。此外，其近期地貌的发育和演变亦受到人类工程活动的重大影响。这些结论可为闽江口航道综合整治工程提供科学理论依据。本文为其第三部分，主要探讨闽江口水下三角洲前缘和前三角洲的地貌特征及演变。 The formation and evolution of the submarine delta in the Minjiang River Estuary Starting from the analysis of the environmental factors that control or affect the development of the submarine delta in the Minjiang River estuary, the geomorphologic features, genesis and evolution of the submarine delta in the Minjiang River Estuary are discussed. The results show that the Minjiang River subaqueous delta is a tectonic-tidal delta, and its features and causes are similar to those of the typical tidal delta. There are also significant differences. In addition, the development and evolution of its recent landform has also been greatly influenced by human engineering activities. These conclusions can provide a scientific basis for the comprehensive regulation of Minjiang Estuary Channel. This is the third part of this paper, which mainly discusses the geomorphic features and evolution of the submarine delta front and the former delta in the Minjiang River estuary.