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Positive biodiversity-ecosystem function relationships (BEFRs) have been widely documented, but it is unclear if BEFRs should be expected in disturbance-driven systems. Disturbance may limit competition and niche differentiation, which are frequently posited to underlie BEFRs. We provide the first exploration of the relationship between tree species diversity and biomass, one measure of ecosystem function, across southern African woodlands and savannas, an ecological system rife with disturbance from fire, herbivores and humans. We used > 1000 vegetation plots distributed across 10 southern African countries and structural equation modelling to determine the relationship between tree species diversity and above-ground woody biomass, accounting for interacting effects of resource availability, disturbance by fire, tree stem density and vegetation type. We found positive effects of tree species diversity on above-ground biomass, operating via increased structural diversity. The observed BEFR was highly dependent on organismal density, with a minimum threshold of c. 180 mature stems ha-1 . We found that water availability mainly affects biomass indirectly, via increasing species diversity. The study underlines the close association between tree diversity, ecosystem structure, environment and function in highly disturbed savannas and woodlands. We suggest that tree diversity is an under-appreciated determinant of wooded ecosystem structure and function.
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Ecosistema , Árboles , Biodiversidad , Bosques , PraderaRESUMEN
(1) Background: the Miombo woodlands comprise the most important vegetation from southern Africa and are dominated by tree legumes with an ecology highly driven by fires. Here, we report on the characterization of bacterial communities from the rhizosphere of Brachystegia boehmii in different soil types from areas subjected to different regimes. (2) Methods: bacterial communities were identified through Illumina MiSeq sequencing (16S rRNA). Vigna unguiculata was used as a trap to capture nitrogen-fixing bacteria and culture-dependent methods in selective media were used to isolate plant growth promoting bacteria (PGPB). PGP traits were analysed and molecular taxonomy of the purified isolates was performed. (3) Results: Bacterial communities in the Miombo rhizosphere are highly diverse and driven by soil type and fire regime. Independent of the soil or fire regime, the functional diversity was high, and the different consortia maintained the general functions. A diverse pool of diazotrophs was isolated, and included symbiotic (e.g., Mesorhizobium sp., Neorhizobium galegae, Rhizobium sp., and Ensifer adhaerens), and non-symbiotic (e.g., Agrobacterium sp., Burkholderia sp., Cohnella sp., Microvirga sp., Pseudomonas sp., and Stenotrophomonas sp.) bacteria. Several isolates presented cumulative PGP traits. (4) Conclusions: Although the dynamics of bacterial communities from the Miombo rhizosphere is driven by fire, the maintenance of high levels of diversity and functions remain unchanged, constituting a source of promising bacteria in terms of plant-beneficial activities such as mobilization and acquisition of nutrients, mitigation of abiotic stress, and modulation of plant hormone levels.
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The data of this article is related to the original article entitled "An expert-based approach to assess the potential for local people engagement in nature conservation: The case study of the Niassa National Reserve in Mozambique" [1], published in Journal for Nature Conservation. The dataset is from an online and self-administrated survey with 55 experts aware of conservation policies and incentives under implementation in the Niassa National Reserve (NNR), the largest protected area in the country and third-largest in Africa. The survey included four sections of both compulsory and non-compulsory questions, mostly in closed-ended Likert-scale. In the first section, experts were asked about the main practices that threaten biodiversity conservation in the NNR, the actors who are directly and indirectly responsible for each practice, and the reasons for local people's involvement with those practices. The second section was about the effectiveness and limitations of the current compensation measures to engage local residents with conservation-friendly practices. In the third section, respondents were asked to select new measures to enhance the current conservation status and engage local people more effectively in conservation. The last section was about the socio-economic profile of respondents. The survey was conducted from June to September 2017. The paper includes the survey itself, raw data in an Excel spreadsheet, descriptive analysis, crosstabulation and Post Hoc cellwise tests (goodness of fit). Data are provided for public use and can serve as a benchmark for collaboration in order to conduct more comprehensive research, comparative analysis as well as panel data can be derived. This data can also have applications in other fields such as mathematics, statistics, and computation.
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The data content of this paper is related to the original research article entitled "Vegetation Structure and Effects of Human Use of the Dambo Ecosystem in Northern Mozambique" that was published in the Global Ecology and Conservation. Woody and grass vegetation was inventoried in the dambos wetlands of the Niassa National Reserve (NNR), the largest Protected Area (PA) in Mozambique and the third largest in Africa. The six dambos assessed were selected through Google Earth, MODIS satellite images and exploratory field visits. The selected dambos were surveyed using a two-stage systematic sampling procedure in which woody vegetation was inventoried by means of transects, and the grass was inventoried using quadratic sub-plots laid down within the transects. The woody vegetation survey included the identification of all individuals to the species level, measurement of total height and diameter at breast height (DBH). The grass vegetation survey consisted of measurement of the total height and species identification within sub-plots. Woody vegetation data in this article includes also estimation of total richness, absolute and relative abundance, dominance, frequency, species volume and successional stage of each species in the vertical structure. Estimation of richness and absolute dominance is also presented for the grass vegetation.