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The need to effectively govern and manage communal rangeland resources has become more important over the past two decades, given the extent of biodiversity loss caused by a myriad of drivers interacting at different scales.Using in‐depth interviews, participant observations and historical information from organisational records, we analysed the application of governance objectives between 1947 and 2017 and their corresponding rangeland condition outcome in Machubeni (South Africa) communal lands.The results show that while the application of governance objectives varied through time, there has been a steady degradation of local rangeland resources since apartheid, due to internal and external drivers of change. This reveals a disconnection between management and resource conditions, suggesting that a return to effective governance alone will not necessarily result in improved rangeland condition in Machubeni, but that more radical steps such as prolonged periods of resting, reseeding and building individual and group agency, are needed. These findings can help practitioners working in post‐colonial territories to design effective rangeland management models. Read the free Plain Language Summary for this article on the Journal blog. Read the free Plain Language Summary can be found within the Supporting Information of this article. [ABSTRACT FROM AUTHOR]

Aim We examined differences in the architecture of African and Australian savanna trees. We sought to attribute variation in tree architecture to current environments, wood density and phylogeny, and thereby elucidate the relative importance of biogeographic idiosyncrasies versus current factors in underpinning architectural differences. Location Africa and Australia. Methods We compiled canopy diameters and stem diameters from 4867 trees of 97 species and heights and stem diameters from 10,786 trees of 155 species from a range of African and Australian savanna ecosystems and climates. Using Bayesian methods we first estimated continental-scale savanna tree allometries, ignoring species differences. We then examined continental differences in species-specific allometries accounting for trait covariation using a phylogeny of our study species. Environmental variables and wood density data were included as covariates, allowing us to assess the potential underpinning of regional differences in tree allometries by differences in current environments and traits. Results Substantial allometric differences exist between Australian and African savanna trees. Australian trees are on average 6 m taller at 20 cm diameter, with a 53% smaller canopy area than African trees. However, this extreme continental-scale variation is driven by the architecture of only a few taxa in this study - Vachellia and Senegalia versus Eucalyptus and Corymbia - rather than systematic differences between species, wood density and environment. These same genera often dominate the woody strata of South African and Australian savannas, respectively. Main conclusions Stark differences in the architecture of African and Australian savanna tree taxa are not a product of environmental differences and are not consistent across species. Rather, the most likely explanation is the different evolutionary histories of African and Australian savannas, which share no woody species. We consider that these architectural differences are likely to impact regional patterns of woody biomass accumulation. [ABSTRACT FROM AUTHOR]

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The frequency of fire has increased in savannas yet few studies have assessed how plants persist when subjected to long-term disturbance by fire. We investigated the contributions of bark thickness and resprouting to the persistence of woody plants in two fire trials that were started in 1948 and 1949. The number of resprouts per individual, bark thickness, basal diameter and height of woody plants were measured in unburnt plots and those burnt annually, triennially and quinquennially during the late dry season. Changes in tree density, number of resprouts and individuals in different height classes between 1963 and 2002 were assessed. Bark thickness varied among species and also increased with increases in basal diameter. Generally, plants with thick bark survived fire more than those with thin bark. Resprouting was the major fire survival strategy for most species. The number of resprouts produced per plant ranged from 4 ± 3 ( Acacia rehmanniana) to 14 ± 9 ( Pseudolachnostylis maprouneifolia). Fire reduced species richness in plots burnt annually and triennially by 47% and 6% respectively. Species richness increased in unburnt plots (5%) and those burnt quinquennially (16%). Most woody species survived fire through a combination of traits. [ABSTRACT FROM AUTHOR]