Fruit and seed traits and vertebrate-fruit interactions of tree species occurring in Guyana, Suriname, and French Guiana.

Seed dispersal is widely considered an important mechanism for the conservation of plant diversity. In tropical regions, over 80% of woody plant species are dispersed by vertebrates, often through the consumption of fruits. Our understanding of what drives interactions between vertebrates and fruits is limited. Through a systematic literature search, we compiled a database of fruit and seed traits and vertebrate-fruit interactions for tree and vertebrate species occurring in the Guianas, with the aim of facilitating research into seed dispersal and seed predation of tree species in the Guianas. The database was compiled by extracting data from 264 published sources. It consists of 21,082 records, of which 19,039 records contain information about 19 different fruit and seed traits belonging to 1622 different tree species. The other 2043 records contain information on vertebrate-fruit interactions between 161 vertebrate species and 464 tree species. Our analyses showed a taxonomic bias, particularly in the interaction data, toward large-bodied vertebrates, with most interactions recorded for the bearded saki (Chiropotes chiropotes), followed by the lowland tapir (Tapirus terrestris). For plants we found an overrepresentation of the Sapotaceae and Moraceae families and an underrepresentation of the Rubiaceae, Myrtaceae, and Lauraceae families in the interactions. There are no copyright restrictions on the data set; please cite this publication when using these data.

Clay and soil organic matter drive wood multi-elemental composition of a tropical tree species: Implications for timber tracing.

Forensic methods to independently trace timber origin are essential to combat illegal timber trade. Tracing product origin by analysing their multi-element composition has been successfully applied in several commodities, but its potential for timber is not yet known. To evaluate this potential the drivers of wood multi-elemental composition need to be studied. Here we report on the first study relating wood multi-elemental composition of forest trees to soil chemical and physical properties. We studied the reactive soil element pools and the multi-elemental composition in sapwood and heartwood for 37 Azobé (Lophira alata) trees at two forest sites in Cameroon. A total of 46 elements were measured using ICP-MS. We also measured three potential drivers of soil and wood elemental composition: clay content, soil organic matter and pH. We tested associations between soil and wood using multiple regressions and multivariate analyses (Mantel test, db-RDA). Finally, we performed a Random Forest analysis of heartwood elemental composition to check site assignment accuracy. We found elemental compositions of soil, sapwood and heartwood to be significantly associated. Soil clay content and organic matter positively influenced individual element concentrations (for 13 and 9 elements out of 46 respectively) as well as the multi-elemental composition in wood. However, associations between wood and topsoil elemental concentrations were only significant for one element. We found close associations between element concentrations and composition in sapwood and heartwood. Lastly, the Random Forest assignment success was 97.3 %. Our findings indicate that wood elemental composition is associated with that in the topsoil and its variation is related to soil clay and organic matter content. These associations suggests that the multi-elemental composition of wood can yield chemical fingerprints obtained from sites that differ in soil properties. This finding in addition to the high assignment accuracy shows potential of multi-element analysis for tracing wood origin.

Privacy-preserving local analysis of digital trace data: A proof-of-concept.

We present PORT, a software platform for local data extraction and analysis of digital trace data. While digital trace data hold huge potential for social-scientific discovery, their most useful parts have been unattainable for scientists because of privacy concerns and prohibitive access to application programming interfaces. Recently, a workflow was introduced allowing citizens to donate their digital traces to scientists. In this workflow, citizens' digital traces are processed locally on their machines before providing informed consent to share a subset of the data with researchers. In this paper, we present the newly developed software PORT that implements the local processing part of this workflow, protecting privacy by shielding sensitive data from outside observers, including the researchers themselves. When using PORT, researchers can tailor the local processing procedure suitable to the data download package and research question. Thus, PORT enables a host of potential applications of social data science to hitherto unobtainable data.