Secondary Miombo woodlands and forest plantations occupy increasing areas in Mozambique, the former due to anthropogenic activities. Plantations, mainly species of Eucalyptus and Pinus, are being established on sites previously covered by secondary Miombo woodlands. This affects the evolution, cycle and spatiotemporal patterns of carbon (C) storage and stocks in forest ecosystems. The estimation of C storage, which is indispensable for formulating climate change policies on sequestrating CO2, requires tools such as biomass models and biomass conversion and expansion factors (BCEF). In Mozambique, these tools are needed for both indigenous forests and plantations. The objective of this study is to fit species-specific allometric biomass models and BCEF for exotic and indigenous tree species. To incorporate efficient inter-species variability, biomass equations were fitted using nonlinear mixed-effects models. All tree component biomass models had good predictability; however, better predictive accuracy and ability was observed for the 2-predictors biomass model with tree height as a second predictor. The majority of the variability in BCEF was explained by the variation in tree species. Miombo species had larger crown biomass per unit of stem diameter and stored larger amounts of biomass per stem volume. However, due to relatively rapid growth, larger stem diameters, heights, and stand density, the plantations stored more biomass per tree and per unit area.

Monoculture plantations replacing native woodlands are increasingly common globally. In Mozambique, vast miombo* woodlands have been replaced by single‐species plantations. Studies on the effect of replacing native woodlands by single‐species tree plantations on soil properties are abundant; however, those focused specifically on the replacement of miombo and considering a longer time since replacement and covering different growth stages are scarce. This article aimed at assessing the effects of the conversion of miombo to monoculture on soil properties and studying the effect of species planted, plantation age, and rotation on soil capacity to store carbon (C) and nitrogen (N). Plantations established in soils formerly covered by miombo were compared to the remaining original miombo with regard to soil properties. The effect of species planted, plantation age, and rotation on soil properties was examined using the three‐way ANOVA, followed by Tukey's test. Miombo conversion to plantations led to an increase of up to 66% of soil organic C (SOC) and 77% of total N (STN) and a decrease in soil bulk density (BD) of up to 16%. The replacement of the first‐ by second‐rotation plantations led to a decrease of up to 38% in SOC and STN and an increase of up to 32% in BD. BD decreased with plantation age; SOC and STN stocks tended to increase: 60 years after the replacement of miombo by plantations, SOC and STN increased by up to 88%. Changes in soil properties due to the replacement of miombo by monoculture were mainly driven by the species planted. * a sparse open deciduous woodland characteristic of dry parts of eastern Africa

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