Farming for nature in the Montado: the application of ecosystem services in a results-based model

The Montado is a silvopastoral system with a tree cover of predominantly Quercus suber but also Quercus rotundifolia, where cattle or sheep graze the understory. It occupies more than one million hectares in southern Portugal, and a similar landscape, the Dehesa, covers ca. three million hectares in Spain. These silvopastoral systems can simultaneously benefit the environment and socio-economic activities by providing a bundle of ecosystem services (ESs). However, an ongoing trend of decline in tree density and the covered area is threat-ening such provision. Policies are needed to motivate farmers to secure the ESs that they provide. One possible format is the development of a results-based model (RBM) for agri-environment schemes (AES), implemented under the Common Agricultural Policy. In an RBM, farmers are paid when they deliver specific environmental results (ERs) (e.g. healthy and functional soils), that are linked with the provision of different (and often mul-tiple) ESs. This study defines possible ERs for the Montado and details how these results are linked to the pro-vision of ESs. It then considers management actions that can allow the achievement of these ERs and the costs of these actions. Our methodological approach is based on a transdisciplinary dialogue involving researchers, practitioners (i.e farmers), public authorities and policy makers. The results of the process include the identi-fication of four main ERs: a healthy soil ecosystem, a biodiverse native-Mediterranean pasture, an oak tree layer where regeneration exists (i.e. trees of different ages), and preserved or enhanced landscape elements, for example riparian galleries with vegetation. These ERs increase the supply of provisioning services (e.g. cork production), of regulating services, (e.g. carbon sequestration), and cultural services (e.g. aesthetic inspiration). RBMs allow farmers to use any management practice they choose as the focus is on the results. Nonetheless, to estimate costs we identified 12 potential strategic management practices (and their cost) along with the technical support that farmers would need. We conclude that an RBM could be an affordable solution for public policies in the Montado system, given the limited government budget for supporting AES.info:eu-repo/semantics/publishedVersio

Genome-wide discovery of small RNAs in Mycobacterium tuberculosis

Only few small RNAs (sRNAs) have been characterized in Mycobacterium tuberculosis and their role in regulatory networks is still poorly understood. Here we report a genome-wide characterization of sRNAs in M. tuberculosis integrating experimental and computational analyses. Global RNA-seq analysis of exponentially growing cultures of M. tuberculosis H37Rv had previously identified 1373 sRNA species. In the present report we show that 258 (19%) of these were also identified by microarray expression. This set included 22 intergenic sRNAs, 84 sRNAs mapping within 59/39 UTRs, and 152 antisense sRNAs. Analysis of promoter and terminator consensus sequences identified sigma A promoter consensus sequences for 121 sRNAs (47%), terminator consensus motifs for 22 sRNAs (8.5%), and both motifs for 35 sRNAs (14%). Additionally, 20/23 candidates were visualized by Northern blot analysis and 59 end mapping by primer extension confirmed the RNA-seq data. We also used a computational approach utilizing functional enrichment to identify the pathways targeted by sRNA regulation. We found that antisense sRNAs preferentially regulated transcription of membrane-bound proteins. Genes putatively regulated by novel cis-encoded sRNAs were enriched for two-component systems and for functional pathways involved in hydrogen transport on the membrane

Mapping density, diversity and species-richness of the Amazon tree flora

Using 2.046 botanically-inventoried tree plots across the largest tropical forest on Earth, we mapped tree species-diversity and tree species-richness at 0.1-degree resolution, and investigated drivers for diversity and richness. Using only location, stratified by forest type, as predictor, our spatial model, to the best of our knowledge, provides the most accurate map of tree diversity in Amazonia to date, explaining approximately 70% of the tree diversity and species-richness. Large soil-forest combinations determine a significant percentage of the variation in tree species-richness and tree alpha-diversity in Amazonian forest-plots. We suggest that the size and fragmentation of these systems drive their large-scale diversity patterns and hence local diversity. A model not using location but cumulative water deficit, tree density, and temperature seasonality explains 47% of the tree species-richness in the terra-firme forest in Amazonia. Over large areas across Amazonia, residuals of this relationship are small and poorly spatially structured, suggesting that much of the residual variation may be local. The Guyana Shield area has consistently negative residuals, showing that this area has lower tree species-richness than expected by our models. We provide extensive plot meta-data, including tree density, tree alpha-diversity and tree species-richness results and gridded maps at 0.1-degree resolution

Consistent patterns of common species across tropical tree communities

Trees structure the Earth’s most biodiverse ecosystem, tropical forests. The vast number of tree species presents a formidable challenge to understanding these forests, including their response to environmental change, as very little is known about most tropical tree species. A focus on the common species may circumvent this challenge. Here we investigate abundance patterns of common tree species using inventory data on 1,003,805 trees with trunk diameters of at least 10 cm across 1,568 locations1,2,3,4,5,6 in closed-canopy, structurally intact old-growth tropical forests in Africa, Amazonia and Southeast Asia. We estimate that 2.2%, 2.2% and 2.3% of species comprise 50% of the tropical trees in these regions, respectively. Extrapolating across all closed-canopy tropical forests, we estimate that just 1,053 species comprise half of Earth’s 800 billion tropical trees with trunk diameters of at least 10 cm. Despite differing biogeographic, climatic and anthropogenic histories7, we find notably consistent patterns of common species and species abundance distributions across the continents. This suggests that fundamental mechanisms of tree community assembly may apply to all tropical forests. Resampling analyses show that the most common species are likely to belong to a manageable list of known species, enabling targeted efforts to understand their ecology. Although they do not detract from the importance of rare species, our results open new opportunities to understand the world’s most diverse forests, including modelling their response to environmental change, by focusing on the common species that constitute the majority of their trees