Reading tea leaves worldwide: Decoupled drivers of initial litter decomposition mass-loss rate and stabilization.

The breakdown of plant material fuels soil functioning and biodiversity. Currently, process understanding of global decomposition patterns and the drivers of such patterns are hampered by the lack of coherent large-scale datasets. We buried 36,000 individual litterbags (tea bags) worldwide and found an overall negative correlation between initial mass-loss rates and stabilization factors of plant-derived carbon, using the Tea Bag Index (TBI). The stabilization factor quantifies the degree to which easy-to-degrade components accumulate during early-stage decomposition (e.g. by environmental limitations). However, agriculture and an interaction between moisture and temperature led to a decoupling between initial mass-loss rates and stabilization, notably in colder locations. Using TBI improved mass-loss estimates of natural litter compared to models that ignored stabilization. Ignoring the transformation of dead plant material to more recalcitrant substances during early-stage decomposition, and the environmental control of this transformation, could overestimate carbon losses during early decomposition in carbon cycle models.

Comment on "The global tree restoration potential".

Bastin et al's estimate (Reports, 5 July 2019, p. 76) that tree planting for climate change mitigation could sequester 205 gigatonnes of carbon is approximately five times too large. Their analysis inflated soil organic carbon gains, failed to safeguard against warming from trees at high latitudes and elevations, and considered afforestation of savannas, grasslands, and shrublands to be restoration.

The world needs BRICS countries to build capacity in invasion science.

Developed countries are producing policies to reduce the flow of invasive species and control or eradicate existing invasions, but most developing countries are under-resourced to tackle either aspect without help. Emerging economies, such as Brazil, Russia, India, China, and South Africa (BRICS), are responsible for donating many of the world's invasive species that have the potential to reach nearly all terrestrial biomes. Implementing a proactive 'facilitated network' model is urgently required to build capacity and stimulate effective appropriate invasion science. We contend that creating a BRICS network of invasion scientists will have the immediate impact required to meet future policy demands.

Artisans and dugout canoes reveal pieces of Atlantic Forest history.

Dugout canoes are boats made from a single tree trunk. Even with the modernization of fishing, they are still made and used for artisanal fishing on the coast of southern and southeastern Brazil and in other regions of the world. Various tree species are used to construct these canoes and choosing a species is related to characteristics of the location, available raw materials and purpose of the boat. Our objective was to better understand the variation in dugout canoes in relation to tree species, tree size and fishing use, over time, along a coastal strip of southern and southeastern Brazil within the Atlantic Forest domain. We interviewed 53 artisans and analyzed 358 canoes that ranged from 1 to around 200 years old. Schizolobium parahyba is currently used the most. In the past, species of the family Lauraceae (Nectandra sp. / Ocotea sp.) were frequently used, as well as Cedrela fissilis and Ficus sp. The size of the canoes varied based on time, coastal region, environment where the boat is used (exposed or sheltered) and type of fishing. The average size of recent canoes was smaller than older canoes for more common species (S. parahyba and C. fissilis), reflecting changes in the vegetation of the biome over time, both in the species and size of individuals available. Latitudinal variation can also influence the availability of tree species along the studied regions. An increase in environmental monitoring has contributed to a decline in constructing dugout canoes, resulting in the use of fiberglass canoes and other motorized boats. Although canoe size varied based on region, location and use, today some of the older canoes represent large trees of the past and pieces of Atlantic Forest history.

The Global Naturalized Alien Flora (GloNAF) database.

This dataset provides the Global Naturalized Alien Flora (GloNAF) database, version 1.2. GloNAF represents a data compendium on the occurrence and identity of naturalized alien vascular plant taxa across geographic regions (e.g. countries, states, provinces, districts, islands) around the globe. The dataset includes 13,939 taxa and covers 1,029 regions (including 381 islands). The dataset is based on 210 data sources. For each taxon-by-region combination, we provide information on whether the taxon is considered to be naturalized in the specific region (i.e. has established self-sustaining populations in the wild). Non-native taxa are marked as "alien", when it is not clear whether they are naturalized. To facilitate alignment with other plant databases, we provide for each taxon the name as given in the original data source and the standardized taxon and family names used by The Plant List Version 1.1 (http://www.theplantlist.org/). We provide an ESRI shapefile including polygons for each region and information on whether it is an island or a mainland region, the country and the Taxonomic Databases Working Group (TDWG) regions it is part of (TDWG levels 1-4). We also provide several variables that can be used to filter the data according to quality and completeness of alien taxon lists, which vary among the combinations of regions and data sources. A previous version of the GloNAF dataset (version 1.1) has already been used in several studies on, for example, historical spatial flows of taxa between continents and geographical patterns and determinants of naturalization across different taxonomic groups. We intend the updated and expanded GloNAF version presented here to be a global resource useful for studying plant invasions and changes in biodiversity from regional to global scales. We release these data into the public domain under a Creative Commons Zero license waiver (https://creativecommons.org/share-your-work/public-domain/cc0/). When you use the data in your publication, we request that you cite this data paper. If GloNAF is a major part of the data analyzed in your study, you should consider inviting the GloNAF core team (see Metadata S1: Originators in the Overall project description) as collaborators. If you plan to use the GloNAF dataset, we encourage you to contact the GloNAF core team to check whether there have been recent updates of the dataset, and whether similar analyses are already ongoing.

Facilitation influences patterns of perennial species abundance and richness in a subtropical dune system.

Positive interactions in plant communities are under-reported in subtropical systems most likely because they are not identified as stressful environments. However, environmental factors or disturbance can limit plant growth in any system and lead to stressful conditions. For instance, salinity and low nutrient and water availability generate a gradient of stressful conditions in coastal systems depending on distance to shore. In a tropical coastal system in SE Brazil, we aimed to assess whether Guapira opposita, a shrub common in restinga environments, acted as nurse involved in ecological succession and which factors influenced its facilitation process. We sampled perennial species above 10 cm in height under the canopy of 35 G. opposita individuals and in neighbouring open areas. Shrub height, canopy area and distance to freshwater bodies were measured in the field, and distance to the ocean was obtained from aerial images. In addition, we measured the distance to the closest forest patch as a potential source of seeds. Plant abundance and species richness were higher under the canopy of G. opposita than in open areas. Facilitation by G. opposita was mainly determined by shrub height, which had a positive relationship with woody and bromeliads abundance and species richness while there was no relationship with the other factors. Overall, our data evidence that tropical environments may be highly stressful for plants and that nurse species play a key role in the regeneration of restinga environments, where their presence is critical to maintain ecosystem diversity and function.