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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 In Mozambique, vast miombo* woodlands have been replaced by single‐species plantations.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 [ABSTRACT FROM AUTHOR]

In wetlands the effects of fire on vegetation dynamics are somewhat uncertain. A change detection analysis in the herbaceous wetlands of KwaMbonambi, South Africa, which were subject to frequent fires, revealed that in 1937 the study area comprised grassland (69%), herbaceous wetland (25%), indigenous swamp forest (4%) and tree plantations (1%). However, by 1970, tree plantations occupied 78% of the landscape and grasslands and herbaceous wetlands had declined to 9% and 6%, respectively, whereas indigenous swamp forest had increased to 6%. By 2009 tree plantations had been removed from the wetland areas. Despite this opportunity for herbaceous wetlands to recover their historical extent, they decreased to only 2%, mostly changing to indigenous swamp forest or to an herbaceous/fern (Stenochlaena tenuifolia)/woodland mosaic. Fire records showed suppression of fire to be an important contributing factor, particularly in wetlands that had been disturbed by tree plantations, although subsequently removed. A pilot burning experiment revealed thatS. tenuifoliadid not inhibit fire. It is therefore practicable to increase fire frequency to prevent the mosaic developing into forest. A conceptual model of the influence of fire regime on wetland vegetation type is presented and priorities for further research on wetlands and fire are recommended. [ABSTRACT FROM PUBLISHER]

Over five million hectares of tropical forest were cleared across mainland Southeast Asia and sub-Saharan Africa for rubber plantations between 2003 and 2017 [1, 2]. Millions of hectares of further clearance are predicted as rubber demand rises, which will have major consequences for biodiversity [3]. A key question is how to reconcile rubber expansion with biodiversity conservation. We assessed the feasibility of simultaneously meeting global future demand for rubber with conservation of extinction-threatened amphibians, birds, mammals, and reptiles. We compared the spatial congruence of rubber bioclimatic suitability with extinction vulnerability [4] in Africa, Asia, and New Guinea, where large-scale rubber cultivation is viable, and simulated rubber expansion under different scenarios. We found no "win-win" areas with highest rubber suitability and lowest extinction vulnerability. Projected rubber demand could be met by allowing expansion primarily in New Guinea and African Guinea. However, New Guinea has high ecosystem intactness and both regions are rich in endemics. Scenarios suggest converting only areas suitable for cultivation would cause the largest biodiversity losses, including endangered species, whereas prioritizing conservation would result in only the conversion of highly unsuitable land. Compromise scenarios that balance production with conservation could cut biodiversity losses by two-thirds, protecting most endangered species while maintaining high rubber suitability. Development of high-yielding hardy clones expands the amount of win-win areas, as well as suitable areas with high extinction risk. These trade-offs reveal that clonal research and development, strategic corporate and government land-use policies, and rigorous impact assessments are needed to prevent severe biodiversity losses from rubber development., Competing Interests: Declaration of Interests The authors declare no competing interests., (Copyright © 2020 Elsevier Inc. All rights reserved.)