Biology subjects

Kreft, H.

Publications and source records attributed to Kreft, H..

At least 19 recordsLinked to original sources

bioRxiv2026

Global failure to track international biodiversity targets on islands

Islands harbour exceptional biodiversity but face severe threats, making their conservation crucial to achieving the goals and targets of the Kunming-Montreal Global Biodiversity Framework. We therefore evaluated whether existing indicators can track progress toward the Framework's 23 targets across islands worldwide. We screened 504 biodiversity and socioeconomic indicators from the official framework and other global initiatives, retaining 47 indicators. Historical time series from 1950 onward were modelled and projected to 2030. Indicators were also classified using the Driver-Pressure-State-Impact-Response (DPSIR) and Theory of Change (ToC). Results showed uneven progress: eight targets improved across all available indicators, while ten displayed conflicting trends. Nearly half of the indicators focused on policy and management responses showed improvement, whereas trends in biodiversity pressures and states were mixed. Critically, 15 of 23 targets (65%) lacked a suitable headline indicator, and five targets had no indicator at all. Notably, Targets 2 and 8, addressing ecosystem restoration and climate change impacts, respectively, lacked island indicators entirely. Over half of the available indicators (29 of 47; 62%) were reported at the national level, limiting their applicability to subnational island jurisdictions and potentially obscuring differences between mainland and island conditions. Most targets also lacked quantitative objectives, limiting evaluation of whether the rate of change is sufficient to meet the targets by 2030. We recommend island-level reporting, island-specific indicators, and quantitative benchmarks tailored to island needs.

ecology↗

bioRxiv2026

Global Convergence of Plant Functional Trait Composition in the Anthropocene

Since the onset of European colonial expansion, humans have accelerated species migration across continents, reshaping plant functional composition and associated ecosystem processes. Plant functional traits-such as leaf area, plant height, or rooting depth-are structured along major axes of variation, including size and leaf economics, that reflect ecological strategies. While human-mediated changes in this trait space have been documented regionally or for specific taxa, there exists no global, grid cell-level quantification of past shifts across major axes of trait variation. Here, we link global citizen science plant occurrence data with data on 37 above- and below-ground traits, and information on native and introduced status for each occurrence. Using dimension-reduction on grid cell-level trait means and introduced species status as a proxy for anthropogenic change, we identify three major axes of functional variation: the size, leaf economics, and life-span axes. By comparing past (native-only) and present-day trait distributions in 3D trait space and geographically, we find prominent region-specific shifts along all three axes. Overall, functional composition converges toward (mostly) smaller, more acquisitive, and shorter-lived assemblages, with region-specific differences in which axis shifts are most pronounced. These results provide the first global estimate of how human-mediated plant introductions have altered ecosystem functional composition in the past centuries, highlighting the spatial patterns and trait dimensions most affected by anthropogenic pressures.

ecology↗

bioRxiv2026

Global Patterns and Drivers of Bee Diversity and Endemism on Islands

Islands harbor a disproportionate share of global biodiversity1, yet insects, even invaluable pollinators such as bees2, remain underrepresented in island biogeography research3. Here, we present the first global checklist of island bees, recording 4,140 species across 306 islands. Although islands comprise only [~]5% of Earths land area, they support [~]20% of global bee diversity, and 43% of insular species are endemic, making up [~]8% of all known bee species. Island bee species richness, mirroring continental trends4, peaks at mid-latitudes. Native richness increases with island area and declines with isolation, consistent with patterns in other taxa5. The strength of species-area relationships varies among biomes and is steepest in mediterranean-type systems, which also support disproportionately high bee richness relative to flowering plant diversity. Endemism is highest on large tropical islands, reflecting extensive in situ diversification. Major centers of bee endemism include Madagascar, Malesia (e.g. the Greater Sundas and New Guinea), and Hawaii, where a single large radiation of Hylaeus (Nesoprosopis) dominates6. Among islands capable of supporting endemic species, endemism scales strongly with total richness. These findings highlight the need to integrate island bee diversity into global conservation planning and position bees as a model for understanding insect evolution and conservation on islands.

ecology↗

bioRxiv2025

Global disruption of plant biogeography by non-native species

Biogeographical regions reflect differences in biotic composition resulting from long-term isolation and biogeographical processes, but how human-mediated introductions of non-native species have altered these biogeographical patterns remains unclear. Using global distribution data of 279,441 native and 10,067 non-native seed plant species, we analyzed the impact of species introductions on global organization of biogeographical regions. We show that species introductions have disrupted plant biogeography, causing the loss of distinct floristic realms and subrealms. Due to the impact of non-native species, geographic proximity and dispersal barriers are less important-- particularly as trade-facilitated species exchange drives floristic homogenization--while environmental factors remain critical in structuring floristic regions. Our findings reveal that plant introductions erode biogeographical distinctness and highlight the urgent need for coordinated action to protect native biotas.

ecology↗

bioRxiv2025

Paleogene mass extinction and ongoing Neogene recolonization shape the tropical African flora

Tropical regions are known to host most of the global biodiversity, yet species richness varies drastically between continents. Tropical Africa has long been recognized as the "odd man out", exhibiting lower plant diversity compared to other tropical continents, but the underlying causes remain debated. Here, we use ferns as a model group to explore the processes responsible for the low diversity of African plants. We find that the current fern diversity in Africa, particularly in humid regions, is up to 84% lower than under similar climatic conditions in the Americas and Asia. Unlike on these continents, where 55-60% of extant fern diversity is the result of in-situ diversification of Gondwanan lineages, only 16% of African fern diversity originates from such lineages. This discrepancy points to significant African extinction periods during the Paleogene and mid-Miocene, likely driven by elevated temperatures and aridification. In contrast, 54% of the extant African fern diversity can be attributed to approximately 530 intercontinental dispersal events during the Neogene, indicating ongoing recolonization of Africa. Our findings provide unprecedented insight into the evolutionary forces shaping plant diversity in tropical Africa and highlight the potential risks posed by ongoing climate change to its botanical heritage.

ecology↗

bioRxiv2025

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↗

bioRxiv2024

GLOBAL BIOGEOGRAPHY AND EVOLUTIONARY DRIVERS OF FERNS WITH CHLOROPHYLLOUS SPORES

About 14% of all fern species have chlorophyllous spores. Unlike their counterparts, chlorophyllous spores lack dormancy and have a shorter viability (i.e. only a few days in some species). Such spores should limit long-distance dispersal and be more susceptible to harsher climatic conditions raising questions about the evolutionary and ecological advantages of this trait. This study aims to assess the global biogeography of chlorophyllous-spored ferns evaluating their underlying environmental and evolutionary drivers. We studied the global distribution of 10,995 fern taxa across 556 geographical regions, and assessed the association of the proportional representation of 1387 chlorophyllous-spored species (CSS) with environmental variables using generalized linear mixed models. To assess the influence of phylogenetic relationships on the distribution of this trait across the phylogeny and across geographic regions, we calculated the phylogenetic signal and phylogenetic distances among species in different assemblages. Species richness of chlorophyllous-spored ferns peaked in the tropics while their proportional representation was highest in temperate and island floras. The proportion of CSS was positively influenced by water availability, but negatively by variables associated with temperature. Spore type was strongly conserved phylogenetically, and CSS assemblages were phylogenetically clustered towards higher latitudes. Our study provides strong evidence that chlorophyllous spores do not limit the geographical distribution of fern species. Their latitudinal distribution patterns can be explain both for environmental and phylogenetic drives.

ecology↗

bioRxiv2024

Unraveling the inverse latitudinal gradient: Environmental and geographic influences on plant diversity in South American coastal lomas

AbstractWater availability is widely recognized for its importance in shaping plant diversity gradients globally. However, even in arid ecosystems such as drylands, a remarkable diversity of plant species can persist. Yet, the environmental, topographic, and geographic drivers that have structured plant diversity gradients within drylands over evolutionary time, and their relative importance, are poorly understood, particularly for understudied ecosystems such as coastal lomas. Here, we evaluated the geographic distribution and drivers of taxonomic and phylogenetic diversity of plants across the coastal lomas of South America, which are isolated fog-fed vegetation oases within the Peruvian and Chilean coastal desert. We collated the most comprehensive data set to date of 72 coastal lomas, and used generalised linear models to assess latitudinal diversity gradients, and evaluated the relative importance of environmental, topographic, and geographic drivers of plant taxonomic and phylogenetic diversity. Notably, we found that both plant species richness and standardized mean nearest taxon distance (MNTD) decreased linearly towards the Equator, while standardized phylogenetic diversity (PD) and mean phylogenetic distance (MPD) exhibited non-linear relationships with latitude, peaking in the hyper-arid core of the Atacama Desert. Our results suggest that current climate, environmental heterogeneity, and geographical factors are the primary drivers of plant diversity. Plant species richness increased with cloud cover, slope, and area, and decreased with soil pH, while standardized PD increased with aridity, elevation, and the human footprint and decreased with distance to the coast. Standardized MNTD increased with elevation, and decreased with increasing area and temperature; standardized MPD increased with slope, and decreased with increasing aridity and distance to the coast. Our results suggest that environmental filtering is not the only macroecological process acting on plant diversity across coastal lomas, and has often been counterbalanced at different points in evolutionary time by factors associated with environmental heterogeneity, possibly reflecting the presence of climate refugia and diverse habitats that promote species coexistence. Also, our results offer empirical evidence supporting an inverse latitudinal gradient in plant diversity across coastal lomas, which emerges as a consequence of multiple factors that influence water availability, both directly and indirectly. Over evolutionary time, these factors may have significantly contributed to shaping the current structure and composition of coastal lomas.

ecology↗

bioRxiv2024

A-Islands: A plant dataset for biodiversity research and species monitoring on Australian islands

Australias coastline is fringed by more than 8,000 continental islands. These islands feature a diverse array of landforms, rock and soil types and geological origins. Some of these islands are among the least invaded, most pristine habitats in Australia and support high plant diversity. Here, we present a new Australia-wide curated dataset for plant species occurrences on islands. Combining information from 1,349 species lists and floras, A-Islands includes data on >6,500 plant species from 844 islands ranging in size from 18 m2 to 4,400 km2, exhibiting different degrees of isolation from the mainland, and spanning all major Australian climate zones. Of these, 251 islands have been repeatedly sampled up to 11 times making it possible to investigate temporal compositional change. A-Islands is open access and will be continuously updated. Its simple data structure consisting of three comma separated files allows easy integration with other Australian and global plant-occurrence databases and can serve as a repository for island research in Australia. Knowing which species occur on Australia's islands will provide opportunities for future research, including studying changes in biodiversity and species-turnover within and among archipelagos, tests of classical island biogeography theory and as a baseline for ecological monitoring and conservation.

ecology↗

bioRxiv2024

Stand structure as the proximate driver of endemic biodiversity and ecosystem functions in tropical mosaic landscapes

Transformation of forests into agricultural lands threatens biodiversity and ecosystem functions globally. In the biodiversity hotspot Madagascar, key ecosystem functions along with highly endemic flora and fauna are under threat. Comprehensive studies identifying proximate drivers are lacking, with no studies accounting for endemic species richness across multiple taxa. We assess how plot-scale stand structural attributes (basal area, leaf area index, diameter diversity, and tree species richness) and landscape-scale forest cover affect biodiversity (species richness of butterflies, ants, birds, amphibians, reptiles, herbaceous plants, and multidiversity) and ecosystem functions (soil organic carbon, predation rate, acoustic diversity index, and multifunctionality) in the tropical mosaic landscape of northeastern Madagascar. Across a prevalent land-use gradient in the region, we sampled five woody land-use types: old-growth forest, forest fragment, woody fallow, forest-derived and fallow-derived vanilla agroforests. Complexly structured stands with a larger basal area and higher tree species richness promoted greater endemic multidiversity and certain ecosystem functions. Landscape-scale forest cover significantly favored, particularly, endemic bird species richness. Our models explained 70% of the variance in endemic multidiversity, 26% in multidiversity, and 43% in multifunctionality. Significant effects directions of our predictors differed between taxa but were univocally positive for endemic species richness. Our findings highlight that a simplified stand structure, resulting from land-use change, substantially reduces endemic biodiversity and ecosystem functions in this historically forested region. Conservation actions should aim at maintaining complex stand structure in forests and agroforests, while restoration interventions should focus on re-building such structures.

ecology↗

bioRxiv2023

Planting diversity begets multifaceted tree diversity in oil palm landscapes

Optimizing restoration outcomes is crucial for enhancing multifaceted diversity, resilience, and ecosystem functioning in monoculture-dominated landscapes globally. Here, we experimentally tested the performance of passive and active restoration strategies to recover taxonomic, phylogenetic, and functional diversity by establishing 52 tree islands in an oil palm landscape. Tree diversity via natural regeneration was shaped by local rather than landscape properties, with the diversity of planted tree species and tree island size driving higher multifaceted diversity. We show that large tree islands with higher initial planted diversity catalyze the recovery of multifaceted diversity at both the local and landscape level, including forest-associated species. Our results demonstrate that planted diversity begets regenerating diversity, overcoming major limitations of natural regeneration in highly modified landscapes. By elucidating the contribution of experimental, local, and landscape drivers to natural regeneration, these findings provide practical insights to make oil palm landscapes more biodiversity-friendly by enhancing functional and phylogenetic diversity within plantations.

ecology↗

bioRxiv2023

Using natural language processing to extract plant functional traits from unstructured text

Functional plant ecology aims to understand how functional traits govern the distribution of species along environmental gradients, the assembly of communities, and ecosystem functions and services. The rapid rise of functional plant ecology has been fostered by the mobilization and integration of global trait datasets, but significant knowledge gaps remain about the functional traits of the [~]380,000 vascular plant species worldwide. The acquisition of urgently needed information through field campaigns remains challenging, time-consuming and costly. An alternative and so far largely untapped resource for trait information is represented by texts in books, research articles and on the internet which can be mobilized by modern machine learning techniques. Here, we propose a natural language processing (NLP) pipeline that automatically extracts trait information from an unstructured textual description of a species and provides a confidence score. To achieve this, we employ textual classification models for categorical traits and question answering models for numerical traits. We demonstrate the proposed pipeline on five categorical traits (growth form, life cycle, epiphytism, climbing habit and life form), and three numerical traits (plant height, leaf length, and leaf width). We evaluate the performance of our new NLP pipeline by comparing results obtained using different alternative modeling approaches ranging from a simple keyword search to large language models, on two extensive databases, each containing more than 50,000 species descriptions. The final optimized pipeline utilized a transformer architecture to obtain a mean precision of 90.8% (range 81.6-97%) and a mean recall of 88.6% (77.4-97%) on the categorical traits, which is an average increase of 21.4% in precision and 57.4% in recall compared to a standard approach using regular expressions. The question answering model for numerical traits obtained a normalized mean absolute error of 10.3% averaged across all traits. The NLP pipeline we propose has the potential to facilitate the digitalization and extraction of large amounts of plant functional trait information residing in scattered textual descriptions. Additionally, our study adds to an emerging body of NLP applications in an ecological context, opening up new opportunities for further research at the intersection of these fields.

ecology↗

bioRxiv2023

Reassessment of the risks of climate change for terrestrial ecosystems

Forecasting the risks of climate change for species and ecosystems is necessary for developing targeted conservation strategies. Previous risk assessments mapped the exposure of the global land surface to changes in climate1-4 However, this procedure is unlikely to robustly identify priority areas for conservation actions because non-linear physiological responses and co-limitation processes ensure that ecological changes will not map perfectly to the forecast climatic changes. Here, we combine ecophysio{-}logical growth models of 135,153 vascular plant species and plant growth form information to transform ambient and future climatologies into phytoclimates, which describe the ability of climates to support the plant growth forms that characterise terrestrial ecosystems. We forecast that 33% to 68% of the global land surface will experience a significant change in phytoclimate by 2070 under RCP 2.6 and RCP 8.5, respectively. Novel phytoclimates without present-day analogue are forecast to emerge on 0.3-2.2% of the land surface, and 0.1-1.3% of currently realised phytoclimates are forecast to disappear. Notably, the geographic pattern of change, disappearance and novelty of phytoclimates differs markedly from the pattern of analogous trends in climates detected by previous studies1,3,4, thereby defining new priorities for conservation actions and highlighting the limits of using untransformed climate change exposure indices in ecologicaI risk assessments. Our findings suggest that a profound transformation of the biosphere is underway and emphasise the need for a timely adaptation of biodiversity management practices.

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bioRxiv2023

Scale-dependent landscape-biodiversity relationships shape multi-taxa diversity in an oil palm monoculture under restoration

Enhancing biodiversity in monoculture-dominated landscapes is a pressing restoration challenge. Tree islands can enhance biodiversity locally, but the role of scale-dependent processes on local biodiversity remains unclear. Using a multi-scale approach, we explored how scale-dependent processes influence the diversity of seven taxa (woody plants, understory arthropods, birds, herbaceous plants and soil bacteria, fauna, and fungi) within 52 experimental tree islands embedded in an oil palm landscape. We show that local, metacommunity (between islands), and landscape properties shaped above- and below-ground taxa diversity, with the stronger effects on above-ground taxa. The spatial extent that best-predicted diversity ranged from 150 m for woody plants to 700 m for understory arthropods with below-ground taxa responding at large spatial extents. Our results underscore the need for multi-scale approaches to restoration. Additionally, our findings contribute to understanding the complex processes shaping multi-taxa diversity and offer insights for targeted conservation and restoration strategies.

ecology↗

bioRxiv2023

Biogeographic context mediates multifaceted diversity-productivity relationships in island and mainland forests

AimGrowing evidence suggests that impacts of biodiversity loss on ecosystem functioning and natures contributions to people are usually negative, yet the magnitude and direction of these impacts can be variable across naturally-assembled ecosystems. A potential driver of variation in diversity-productivity relationships is the biogeographical context, which may alter these relationships via processes acting on the size and composition of the species pool like dispersal limitation, environmental filtering, speciation, and invasibility. However, the extent to which the relationships between biodiversity facets and forest productivity are shaped by the biogeographic context remains uncertain. Here, we examine the effects of taxonomic, phylogenetic, and functional tree diversity on aboveground productivity in climatically similar forests on islands and mainland. LocationContinental and insular Spain. Time period1997-2018. Major taxa studiedTrees. MethodsUsing plot data from a national forest inventory, we assessed the influence of taxonomic, phylogenetic, and functional diversity on aboveground productivity using linear models and structural equation models, while accounting for environmental conditions, non-native species, and the number of trees. ResultsWe find that drier environmental conditions lead to a decrease in productivity and in the number of trees in both island and mainland forests. In island forests, non-native species increased productivity directly and via their effects on phylogenetic diversity. Main conclusionsOur results suggest that multifaceted diversity, by capturing the diversity of evolutionary history, contributes to elucidating diversity-productivity relationships in island forests that could not be detected otherwise by taxonomic diversity alone. By filling empty niches in island forests, we find that non-native species are fundamentally altering ecosystem functioning on islands.

ecology↗

bioRxiv2023

GIFT an R package to access the Global Inventory of Floras and Traits

O_LIAdvancing knowledge of biodiversity requires open-access global databases and workflows. This appears particularly crucial for plants, as ongoing changes pose major threats to this central group of organisms. Having large-scale information on plant distributions, functional traits and evolutionary history will enable the scientific community to improve its understanding of the patterns and drivers of plant diversity on a global scale. C_LIO_LIThe Global Inventory of Floras and Traits (GIFT) is a global database of regional plant checklists that has proven successful in documenting biogeographical and geographical patterns of plants. Since the release of the first version of GIFT, the database kept on expanding. We introduce GIFT version 3.0, which contains 5,169 checklists referring to 3,400 regions. These checklists include a total of 371,148 land plant species, mostly vascular plants, of which 354,848 are accepted species names, and 109 functional traits. This new version uses new resources for taxonomic name standardization, is matched to a new plant phylogeny, comes with a new trait aggregation workflow, and includes additional environmental variables. C_LIO_LIWe also present the GIFT R-package, which contains all necessary functions to retrieve distributional, functional, phylogenetic, and environmental data from the GIFT database. The package comes with a dedicated website, https://biogeomacro.github.io/GIFT/, which includes three rich vignettes to guide users in retrieving data from GIFT. C_LIO_LIThe recent development of GIFT and its associated R-package provide ecologists with access to one of the largest plant databases. This will foster research into regional to global patterns of plant diversity and their underlying mechanisms. Proper versioning of the database and the ability to retrieve and cite data from any previous and current instance of the GIFT database will ensure the reproducibility of studies that utilize it. C_LI

ecology↗

bioRxiv2023

The contribution of plant life and growth forms to global gradients of vascular plant diversity

Plant life and growth forms (shortened to plant forms) represent key functional strategies of plants in relation to their environment and provide important insights into the ecological constraints acting on the distribution of biodiversity. Despite their ecological importance, how the spectra of plant forms contribute to global gradients of plant diversity is unresolved. Using a novel dataset comprising >295,000 species, we quantify the contribution of different plant forms to global gradients of vascular plant diversity. Further, we establish how plant form distributions in different biogeographical regions are associated with contemporary and paleoclimate conditions, environmental heterogeneity, and phylogeny. We find a major shift in representation by woody perennials in tropical latitudes to herb-dominated floras in temperate and boreal regions, following a sharp latitudinal gradient in plant form diversity from the tropics to the poles. We also find significant functional differences between regions, mirroring life and growth form responses to environmental conditions, which is mostly explained by contemporary climate (18-87%), and phylogeny (6-62%), with paleoclimate and heterogeneity playing only a minor role (<23%). This research highlights variation in the importance of different plant forms to diversity gradients worldwide, providing a much-needed quantification for long-standing ideas and concepts structuring plant assemblages.

ecology↗

bioRxiv2022

Phylogenetic endemism of the world's seed plants

Assessing phylogenetic endemism, i.e., the distribution of geographically restricted and evolutionarily unique species, is key to understanding biogeographic patterns and processes and critical for global conservation planning. Here, we quantified the geographic distribution and drivers of phylogenetic endemism for ~320,000 seed plants worldwide and identified centers and drivers of evolutionarily young (neoendemism) and evolutionarily old endemism (paleoendemism). Tropical and subtropical islands of the Southern Hemisphere as well as tropical mountainous regions displayed the worlds highest phylogenetic endemism. Tropical moist forests (e.g. Amazonia) and continental islands in south-east Asia emerged as centers of paleoendemism, while both high neo- and paleoendemism were found on ancient continental fragment islands (e.g. Madagascar) and in Mediterranean-climate regions. Global variation in phylogenetic endemism was best explained by a combination of past and present environmental factors (80.3% - 88.1% of variance explained). Geographic isolation and environmental heterogeneity emerged as primary drivers promoting high phylogenetic endemism. Also, warm and wet climates with long-term climatic stability showed a significant positive effect. However, environmental effects on phylogenetic endemism varied with geographic isolation, reflecting the unique evolutionary and biogeographic dynamics on oceanic islands. Long-term climatic stability promoted the persistence of paleoendemics, while isolation promoted higher neoendemism leading to oceanic islands and tropical mountainous regions being centers of both neo- and paleoendemism. Our study provides new insights into the evolutionary underpinnings of biogeographic patterns in seed plants, and by identifying areas of high evolutionary and biogeographic uniqueness, it may serve as a key resource for setting global conservation priorities.

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