Palaeogeography and dynamics of the deltaic wetland of Save River, Mozambique.

摘要: Abstract Many mangrove wetland systems in deltaic environments are negatively affected by massive sedimentation from river inflows. In this paper we use the example of Save River delta to assess palaeogeographic distribution wetlands and analyze their dynamics. To track past occurrences study area have integrated sedimentological data with siliceous microfossil analysis combined AMS radiocarbon OSL dating. The results show a fine-grained deposit an approximate thickness 2 m, present at different sampling sites. upper plain, is interbedded between sand layers, while lower plain occupies uppermost stratigraphic position. most sites shows succession brackish-marine diatoms bottom sequence part only scattered occurrences. Based on characteristics interpreted layer represent deposit. development suggested been initiated around 3100 cal. yr BP, induced sea-level rise. Thereafter, followed effect fall progradation processes. some areas, particularly proximal delta, has developed progressively top delta-front. From 1300 years ago (OSL) onwards, alluvial impacted ecosystem. However, retreat coincided regional sea level. At edges deposit, current ecosystem reclaimed habitat sectors where gully erosion exposed once extinct habitat.