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Mucina, L.

Publications and source records attributed to Mucina, L..

3 recordsLinked to original sources

From smartphones to satellites: Uniting crowdsourced biodiversity monitoring and Earth observation to fill the gaps in global plant trait mapping

Plant functional traits are fundamental to ecosystem dynamics and Earth system processes, but their global characterization is limited by the availability of field surveys and trait measurements. Recent expansions in biodiversity data aggregation, including large collections of vegetation surveys, citizen science observations, and trait measurements, offer new opportunities to overcome these constraints. Here we demonstrate that combining these diverse data sources with high-resolution Earth observation data enables accurate modeling of key plant traits at up to 1 km resolution. Our approach achieves high predictive power, reaching correlations up to 0.63 (15 of 31 traits exceeding 0.50) and improved spatial transferability, effectively bridging gaps in under-sampled regions. By capturing a broad range of traits with high spatial coverage, these maps can enhance our understanding of plant community properties and ecosystem functioning globally, and can serve as useful tools in modeling global biogeochemical processes and informing worldwide conservation efforts. Ultimately, our framework highlights the power and necessity of crowdsourced biodiversity data in high-resolution plant trait modeling. We anticipate that advancements in biodiversity data collection and remote sensing capabilities will further refine global trait mapping, fostering a dynamic trait-based understanding of the biosphere.

ecology↗

A tough nutlet to crack: resolving the phylogeny of Thesium (Thesiaceae), the largest genus in Santalales

With over 350 species, Thesium is the largest genus in Santalales. It is found on all continents except Antarctica; however, its highest diversity is in the Cape Floristic Region of South Africa where approximately half the species occur. Thesium samples of ca. 590 collections from throughout its entire geographic range were obtained and nuclear ribosomal ITS sequenced from 396 accessions representing 196 named taxa and 30 currently unnamed taxa for a total of ca. 230 species. In addition, two chloroplast genome spacers (trnDT and trnLF) were sequenced from 269 and 315 accessions, respectively. Maximum parsimony, maximum likelihood and Bayesian methods were employed to generate gene trees and infer phylogenies. The value of the morphological characters traditionally used in the taxonomy of the genus and previous infrageneric classifications are discussed. Broad scale relationships were generally congruent among the ITS and the chloroplast trees. For example, both the nuclear and chloroplast trees support the presence of Eurasian and African clades. In contrast, major incongruence was detected between nuclear and chloroplast trees for a number of taxa including the recently described T. nautimontanum that is sister to the entire African clade on the ITS tree. Although the causes of this incongruence are currently unknown, a novel form of chloroplast capture is hypothesized. A hypothesis of the biogeographical history of the genus based on our molecular phylogeny is presented.

evolutionary biology↗

Functional diversification enabled grassy biomes to fill global climate space

Global change impacts on the Earth System are typically evaluated using biome classifications based on trees and forests. However, during the Cenozoic, many terrestrial biomes were transformed through the displacement of trees and shrubs by grasses. While grasses comprise 3% of vascular plant species, they are responsible for more than 25% of terrestrial photosynthesis. Critically, grass dominance alters ecosystem dynamics and function by introducing new ecological processes, especially surface fires and grazing. However, the large grassy component of many global biomes is often neglected in their descriptions, thereby ignoring these important ecosystem processes. Furthermore, the functional diversity of grasses in vegetation models is usually reduced to C3 and C4 photosynthetic plant functional types, omitting other relevant traits. Here, we compile available data to determine the global distribution of grassy vegetation and key traits related to grass dominance. Grassy biomes (where > 50% of the ground layer is covered by grasses) occupy almost every part of Earths vegetated climate space, characterising over 40% of the land surface. Major evolutionary lineages of grasses have specialised in different environments, but species from only three grass lineages occupy 88% of the land area of grassy vegetation, segregating along gradients of temperature, rainfall and fire. The environment occupied by each lineage is associated with unique plant trait combinations, including C3 and C4 photosynthesis, maximum plant height, and adaptations to fire and aridity. There is no single global climatic limit where C4 grasses replace C3 grasses. Instead this ecological transition varies biogeographically, with continental disjunctions arising through contrasting evolutionary histories.\n\nSignificance statementWorldviews of vegetation generally focus on trees and forests but grasses characterize the ground layer over 40% of the Earths vegetated land surface. This omission is important because grasses transform surface-atmosphere exchanges, biodiversity and disturbance regimes. We looked beneath the trees to produce the first global map of grass-dominated biomes. Grassy biomes occur in virtually every climate on Earth. However, three lineages of grasses are much more successful than others, characterizing 88% of the land area of grassy biomes. Each of these grass lineages evolved ecological specializations related to aridity, freezing and fire. Recognizing the extent and causes of grass dominance beneath trees is important because grassy vegetation plays vital roles in the dynamics of our biosphere and human wellbeing.

ecology↗