Mangrove Soil in Physiographic Zones in the Sao Francisco River Estuary

Abstract

Mangrove ecosystem dynamics and diverse human activities have led to a need for studies that give us a better understanding of the peculiarities of their soils. The objective of this study was to evaluate the physical and chemical soil attributes of mangrove forests located in the São Francisco River estuary, related to local ecological conditions. Two stations, divided into three forest types (fringe, basin and transition) were selected and five composite soil samples were collected from each forest type. Soil samples were submitted for chemical and physical analysis. The soil presented a sandy texture, with high organic matter and element content in the following order: Mg 2+ >Na + >Ca 2+ >H + >K + >P>Al 3+ and Fe 2+ >Zn 2+ >Cu 2+ >Mn 2+ , respectively, with variations between the forests and stations. In general, the mangrove forests presented high fertility, especially in the basin forest, provided by vegetation development, showing a zoning trend for species in relation to soil fertility.

Dendrometrical Structure and Physicochemical Analysis of Mangrove Sediments from the Nyong River Estuary (Cameroon, Atlantic Coast)

“…The Ca 2+ and Mg 2+ cations have higher average values than Na + and K + . This decreasing order of macronutrients in mangrove estuary soils is similar to that observed by Andrade et al [102] in the Sã o Francisco estuary in Brazil. The Na + values evolve in a decreasing way from the mouth to the upstream of the river with a non-significant difference between stations.…”

IUCN Red List of Ecosystems, Mangroves of the Western Indian Ocean

“…Mangrove pixels were classified as degraded if two conditions were met: 1) at least 10 out of 12 degradation indices showed a decrease of more than 40% compared to the previous period; and 2) all twelve indices did not recover to within 20% of their pre-2000 value (detailed methods and data are available at: maps.oceanwealth.org/mangrove-restoration/). The decay in vegetation indices has been used to identify mangrove degradation and abrupt changes, including mangrove die-back events, clear-cutting, fire damage, and logging; as well as to track mangrove regeneration (Lovelock et al, 2017;Santana et al, 2018;Otero et al, 2018Otero et al, , 2019Murray et al, 2020;Lucas et al, 2020;Aljahdali et al, 2021;Lee et al, 2021;Lucas et al, 2021). However, it is important to consider that changes observed in the vegetation indices can also be influenced by data artefacts (Akbar et al, 2020).…”

Relationship Between Physical and Chemical Properties of Entisols-Fluvents and Erosion in the São Francisco River

“…Using chemical soil properties as parameters in the study of soil quality plays an important role due to the low cost and fast methods, which allow a direct relationship with physical properties (ANDRADE et al, 2018). Knowing soil chemical properties such as acidity; contents of Al 3+ , Ca 2+ , Mg 2+ , Na + , K + , P, Fe 2+ , Cu 2+ , Mn 2+ , and Zn 2+ ; sum of bases (SB); cation exchange capacity (CEC); potential acidity (H + Al); and total organic carbon (TOC) (HOLANDA et al, 2017), in addition to their intrinsic relations, is of vital importance for a better understanding of erosion processes on slopes and for the generation of knowledge to increase their stability (MACHADO et al, 2015).…”

“…In the layers Ap and Ac, additional increases of organic carbon in the soil may have occurred due to higher inputs of organic material. Increases in organic carbon in the soil are due to supply of organic matter such as senescent biomass components above and below the soil, leaf fall, waste from cropping operations, dead animals, and respective decomposition rates (ANDRADE et al 2018).…”