Forest Structure and Carbon Reserve in Natural and Replanted Mangrove Forests in Different Years in the Limpopo Estuary, Gaza Province, Mozambique

Abstract

The Limpopo estuary mangrove forest covers about 928 ha; however, 382 ha remain intact, and 546 ha were degraded after the 2000 floods. Mangrove replanting campaigns were carried out at the site. This study assesses the ability of restored forests to provide carbon storage functions. The results showed that A. marina was the dominant species in all study areas. The carbon reserve of living biomass above and below ground in the natural forest was 67.9 ± 100.9 MgCha−1 and 65.0 ± 77.1 MgC ha−1, respectively; in the planted forests (2016, 2014, 2010), it was 1.1 ± 0.5 MgCha−1 and 2.1 ± 1.0 MgCha−1, 1.8 ± 1.0 MgCha−1 and 3.6 ± 2.0 MgCha−1, 3.7 ± 2.0 MgCha−1 and 5.3 ± 2.5 MgCha−1. Soil carbon reserve was 229.4 ± 119.4 MgCha−1 in natural forest and 230.3 ± 134.8 MgCha−1, 234.8 ± 132.7 MgC ha−1, 229.4 ± 119.4 MgCha−1 in planted forests (2016, 2014, 2010). The total carbon reserve in the natural forest was 362.3 MgCha−1; and 233.5 MgCha−1, 240.2 MgCha−1 and 246.4 MgCha−1 in the planted forests (2016, 2014, 2010), respectively. Natural and restored forests had similar amounts of soil carbon, which reinforces the idea that soil is a stable carbon pool. Moreover, restored forests failed to store the same amount of live biomass (carbon), which supports the idea that it is better to prevent habitat degradation than to restore it.