Wissenschaft ermöglicht durch Exemplardaten

Tiwary, R., P. P. Singh, D. Adhikari, M. D. Behera, and S. K. Barik. 2024. Vulnerability assessment of Taxus wallichiana in the Indian Himalayan Region to future climate change using species niche models and global climate models under future climate scenarios. Biodiversity and Conservation. https://doi.org/10.1007/s10531-024-02859-0

Climate change is a major threat to biodiversity as many species are facing the risk of extinction due to their inability to adapt to the changes in temperature, precipitation, and other environmental variables. The impact of climate change on the habitat distribution of Taxus wallichiana , a medicinally important endangered tree species, has not been studied specifically for the Indian Himalayan region (IHR). We assessed the vulnerability of the species to climate change using Ecological Niche Modeling (ENM) in conjunction with two latest global climate models (GCMs) viz., HadGEM3-GC31-LL and IPSL-CM6A-LR, under two future scenarios i.e. Shared Socioeconomic Pathways (SSPs) - SSP126 and SSP585 from Intergovernmental Panel on Climate Change (IPCC) Sixth Assessment Report, 2023. Based on current distribution of the species and bioclimatic conditions., the Maxent-derived projections indicated significant reduction in its suitable habitat in IHR. Under the moderate scenario i.e. SSP126, suitable habitats are expected to decrease to 6,313,494 ha (10.62% of the total geographical area of IHR) with HadGEM3-GC31-LL and to 4,161,437 ha (7.00%) with IPSL-CM6A-LR from the present distribution area of 8,132,637 ha (13.68%). Under high-emission SSP585 scenario, the predicted habitat area is expected to decline to 4,833,212 ha (8.13%) with HadGEM3-GC31-LL and to 3,204,306 ha (5.39%) with IPSL-CM6A-LR.Annual mean temperature, isothermality, and annual precipitation were important environmental variables impacting the species distribution and models’ predictive capacity. The model outputs clearly predict a gloomy picture under both the future climate scenarios for T. wallichiana emphasizing the need for a targeted conservation effort for the species. .

Serra‐Diaz, J. M., J. Borderieux, B. Maitner, C. C. F. Boonman, D. Park, W. Guo, A. Callebaut, et al. 2024. occTest: An integrated approach for quality control of species occurrence data. Global Ecology and Biogeography. https://doi.org/10.1111/geb.13847

Aim Species occurrence data are valuable information that enables one to estimate geographical distributions, characterize niches and their evolution, and guide spatial conservation planning. Rapid increases in species occurrence data stem from increasing digitization and aggregation efforts, and citizen science initiatives. However, persistent quality issues in occurrence data can impact the accuracy of scientific findings, underscoring the importance of filtering erroneous occurrence records in biodiversity analyses.InnovationWe introduce an R package, occTest, that synthesizes a growing open‐source ecosystem of biodiversity cleaning workflows to prepare occurrence data for different modelling applications. It offers a structured set of algorithms to identify potential problems with species occurrence records by employing a hierarchical organization of multiple tests. The workflow has a hierarchical structure organized in testPhases (i.e. cleaning vs. testing) that encompass different testBlocks grouping different testTypes (e.g. environmental outlier detection), which may use different testMethods (e.g. Rosner test, jacknife,etc.). Four different testBlocks characterize potential problems in geographic, environmental, human influence and temporal dimensions. Filtering and plotting functions are incorporated to facilitate the interpretation of tests. We provide examples with different data sources, with default and user‐defined parameters. Compared to other available tools and workflows, occTest offers a comprehensive suite of integrated tests, and allows multiple methods associated with each test to explore consensus among data cleaning methods. It uniquely incorporates both coordinate accuracy analysis and environmental analysis of occurrence records. Furthermore, it provides a hierarchical structure to incorporate future tests yet to be developed.Main conclusionsoccTest will help users understand the quality and quantity of data available before the start of data analysis, while also enabling users to filter data using either predefined rules or custom‐built rules. As a result, occTest can better assess each record's appropriateness for its intended application.

Barman, M., A. Barman, and S. Ray. 2024. Clerodendrum inerme (L.) Gaertn.: a critical review on current progress in traditional uses, phytochemistry, pharmacological aspects and toxicity. Phytochemistry Reviews. https://doi.org/10.1007/s11101-024-09934-y

Clerodendrum inerme (L.) Gaertn., commonly known as garden quinine, is a perennial shrub that belongs to the Lamiaceae family. It has been extensively used in various traditional medicinal practices to treat ailments such as rheumatic pain, arthritis, scrofulous, venereal disease, skin diseases, wounds, fever, cough, dysentery, and more. This review aims to critically examine a comprehensive compilation of recent research on C. inerme , encompassing its botanical characteristics, ethnomedical applications, phytochemicals, pharmacological activity, and toxicological data, in order to provide insights and inspiration for future research, promote further development, and facilitate the rational application of C. inerme. Nearly 95 chemical constituents belonging to different classes have been isolated from C. inerme , including diterpenoids, triterpenoids, steroids, flavonoids, phenolic glycosides, lignans, iridoid and megastigmane glycosides. Notably, diterpenoids, triterpenoids, steroids, and flavonoids are the main bioactive substances that have been extensively studied and demonstrated the most significant bioactivity. Pharmacological studies demonstrated that the extract of C. inerme exhibits a wide range of biological activities, such as antioxidant, antimicrobial, anticancer, antiinflammatory, insecticidal, antifeedant, neuroprotective, anti-motor tic, and so on, which are closely connected to its numerous ethnomedicinal applications. Nevertheless, some literature have reported the toxicity of C. inerme . Therefore, it is imperative to conduct further in-depth studies encompassing toxicology, as well as preclinical and clinical research, to ascertain the safety and efficacy of C. inerme for medicinal purposes. Graphical abstract

Ramírez-Barahona, S. 2024. Incorporating fossils into the joint inference of phylogeny and biogeography of the tree fern order Cyatheales R. Warnock, and M. Zelditch [eds.],. Evolution. https://doi.org/10.1093/evolut/qpae034

Present-day geographic and phylogenetic patterns often reflect the geological and climatic history of the planet. Neontological distribution data are often sufficient to unravel a lineage’s biogeographic history, yet ancestral range inferences can be at odds with fossil evidence. Here, I use the fossilized birth–death process and the dispersal–extinction cladogenesis model to jointly infer the dated phylogeny and range evolution of the tree fern order Cyatheales. I use data for 101 fossil and 442 extant tree ferns to reconstruct the biogeographic history of the group over the last 220 million years. Fossil-aware reconstructions evince a prolonged occupancy of Laurasia over the Triassic–Cretaceous by Cyathealean tree ferns, which is evident in the fossil record but hidden from analyses relying on neontological data alone. Nonetheless, fossil-aware reconstructions are affected by uncertainty in fossils’ phylogenetic placement, taphonomic biases, and specimen sampling and are sensitive to interpretation of paleodistributions and how these are scored. The present results highlight the need and challenges of incorporating fossils into joint inferences of phylogeny and biogeography to improve the reliability of ancestral geographic range estimation.

Anest, A., Y. Bouchenak-Khelladi, T. Charles-Dominique, F. Forest, Y. Caraglio, G. P. Hempson, O. Maurin, and K. W. Tomlinson. 2024. Blocking then stinging as a case of two-step evolution of defensive cage architectures in herbivore-driven ecosystems. Nature Plants. https://doi.org/10.1038/s41477-024-01649-4

Dense branching and spines are common features of plant species in ecosystems with high mammalian herbivory pressure. While dense branching and spines can inhibit herbivory independently, when combined, they form a powerful defensive cage architecture. However, how cage architecture evolved under mammalian pressure has remained unexplored. Here we show how dense branching and spines emerged during the age of mammalian radiation in the Combretaceae family and diversified in herbivore-driven ecosystems in the tropics. Phylogenetic comparative methods revealed that modern plant architectural strategies defending against large mammals evolved via a stepwise process. First, dense branching emerged under intermediate herbivory pressure, followed by the acquisition of spines that supported higher speciation rates under high herbivory pressure. Our study highlights the adaptive value of dense branching as part of a herbivore defence strategy and identifies large mammal herbivory as a major selective force shaping the whole plant architecture of woody plants. This study explores the evolution of two traits, branching density and spine presence, in the globally distributed plant family Combretaceae. These traits were found to have appeared in a two-step process in response to mammalian herbivory pressure, revealing the importance of large mammals in the evolution of plant architecture diversity.

Rautela, K., A. Kumar, S. K. Rana, A. Jugran, and I. D. Bhatt. 2024. Distribution, Chemical Constituents and Biological Properties of Genus Malaxis. Chemistry & Biodiversity. https://doi.org/10.1002/cbdv.202301830

The genus Malaxis (family Orchidaceae), comprises nearly 183 species available across the globe. The plants of this genus have long been employed in traditional medical practices because of their numerous biological properties, like the treatment of infertility, hemostasis, burning sensation, bleeding diathesis, fever, diarrhea, dysentery, febrifuge, tuberculosis, etc. Various reports highlight their phytochemical composition and biological activities. However, there is a lack of systematic review on the distribution, phytochemistry, and biological properties of this genus. Hence, this study aims to conduct a thorough and critical review of Malaxis species, covering data published from 1965 to 2022 with nearly 90 articles. Also, it examines different bioactive compounds, their chemistry, and pharmacotherapeutics as well as their traditional uses. A total of 191 unique compounds, including the oil constituents were recorded from Malaxis species. The highest active ingredients were obtained from Malaxis acuminata (103) followed by Malaxis muscifera (50) and Malaxis rheedei (33). In conclusion, this review offers an overview of the current state of knowledge on Malaxis species and highlights prospects for future research projects on them. Additionally, it recommends the promotion of domestication studies for rare medicinal orchids like Malaxis and the prompt implementation of conservation measures.

Boral, D., and S. Moktan. 2024. Modelling current and future potential distribution of medicinal orchids in Darjeeling eastern Himalaya. Plant Ecology. https://doi.org/10.1007/s11258-023-01392-4

Species distribution modelling remains a valuable tool for managing conservation practices for medicinal plants. As climate change threatens the planet’s biodiversity, it has become imperative to investigate its impact on our important bioresources. We studied the distribution of two medicinally essential orchid taxa, Crepidium acuminatum and Satyrium nepalense, in the Darjeeling Himalayan region using MaxEnt modelling. AUC (Area Under the Curve) and the TSS (True Skill Statistic) value for the models was calculated to gauge model performance. The models generated via MaxEnt performed excellently with > 0.9 AUC value and 0.6 to > 0.85 TSS value. The most influential factor affecting the distribution of C. acuminatum seems to be precipitation, whilst the factor affecting S. nepalense is altitude. The current potential habitat of C. acuminatum and S. nepalense was 385.25 km 2 (12.51%) and 245.25 km 2 (7.96%), respectively. Of the total current potential habitat, only 108.75 km 2 (3.53%) and 61.5 km 2 (2.0%) were of good habitat suitability for C. acuminatum and S. nepalense, respectively. Similarly, only 100.5 km 2 (3.26%) and 43.5 km 2 (1.41%) were of excellent habitat suitability for C. acuminatum and S. nepalense, respectively. Hence, Maxent identified highly suitable regions for the conservation of both species. The model predicts that for C. acuminatum, the total suitable habitat may decrease by as much as 113.25 km 2. In contrast, for S. nepalense, the total suitable habitat may increase by as much as 230.25 km 2 in future scenarios. However, when suitable habitat increases in certain regions for both species, the habitat is usually of poor suitability. This reflects the strong effect of climate change on the future of medicinal plants, particularly orchids. Hence, this indicates the need for better monitoring and holistic conservation strategies.

Xiao, S., S. Li, J. Huang, X. Wang, M. Wu, R. Karim, W. Deng, and T. Su. 2024. Influence of climate factors on the global dynamic distribution of Tsuga (Pinaceae). Ecological Indicators 158: 111533. https://doi.org/10.1016/j.ecolind.2023.111533

Throughout the Quaternary period, climate change has significantly influenced plant distribution, particularly affecting species within the genus Tsuga (Endl.) Carrière. This climatic impact ultimately led to the extinction of all Tsuga species in Europe. Today, there are ten recognized species of Tsuga worldwide, one of listed as a vulnerable species and four as near-threatened species. The genus Tsuga exhibits a disjunctive distribution in East Asia (EA), eastern North America (ENA), and western North America (WNA). It is crucial to comprehend the mechanisms underlying these distributional changes and to identify key climate variables to develop effective conservation strategies for Tsuga under future climate scenarios. In this study, we applied the maximum entropy (MaxEnt) model by combining distribution data for Tsuga with abundant pollen fossil data. Our objective was to investigate the climate factors that shape the distribution of Tsuga, identify climate thresholds, and elucidate distribution dynamics in the context of significant climate changes over the past 1070 thousand years (ka). Our findings highlight the pivotal role of precipitation as the key climate factor affecting the distribution of Tsuga. Specifically, in EA, summer precipitation was the key driver, while in North America (NA), winter precipitation exerted greater importance. Moreover, we observed similarities in climatic requirements between Tsuga species in Europe and EA, and declines in summer precipitation and winter temperature were major factors contributing to the extinction of Tsuga species in Europe. Quaternary glacial and interglacial fluctuations exerted substantial impacts on Tsuga distribution dynamics. The disappearance of Tsuga species in the Korean Peninsula may have occurred during the LGM (Last Glacial Maximum). The potential suitable area for Tsuga species in EA expanded during the cold periods, while in NA, it contracted. In the future, climate change may result Tsuga distribution area contraction in both the EA and NA. Our study has identified distinct response patterns of Tsuga in various geographic regions to Quaternary climate change and offers corresponding suggestions for Tsuga conservation. In the future, it will be imperative to prioritize the conservation of natural Tsuga distributions in EA and NA, with a focus on the impacts of precipitation fluctuation on the dynamic distribution of this genus.

Huang, L., S. Li, W. Huang, J. Jin, and A. A. Oskolski. 2024. Late Pleistocene glacial expansion of a low-latitude species Magnolia insignis: Megafossil evidence and species distribution modeling. Ecological Indicators 158: 111519. https://doi.org/10.1016/j.ecolind.2023.111519

The Pleistocene Epoch, marked by significant climatic fluctuations and glaciations, profoundly impacted plant populations. However, our understanding of the influences of last glaciations on tropical-subtropical flora and vegetation remains limited due to insufficient data. Here, we present mummified wood of Magnolia insignis (Wall.) Bl. from the Upper Pleistocene (33–30 ka cal. BP) of Maoming, South China, providing direct evidence of a broader historical range for this species during the period prior to the LGM in the last glaciation. Combining these findings with results from MaxEnt modeling, we demonstrate an expanded range of M. insignis into lower latitudes during last glaciation with subsequent interglacial contraction. This represents the second documented case of such a scenario for a cold-tolerant high-elevation plant species at low latitudes. The results of MaxEnt modeling and a comparison of climatic data across different time periods indicate that the contraction of M. insignis from the Maoming and other low latitude regions of East Asia was driven by the increase in summer temperatures during Holocene. This study not only sheds light on the responses of cold-adapted mountainous species at low latitudes of East Asia to last glaciation, but also justifies the importance of their protection in the view of nowadays and future climate changes.

Zhang, H., W. Guo, and W. Wang. 2023. The dimensionality reductions of environmental variables have a significant effect on the performance of species distribution models. Ecology and Evolution 13. https://doi.org/10.1002/ece3.10747

How to effectively obtain species‐related low‐dimensional data from massive environmental variables has become an urgent problem for species distribution models (SDMs). In this study, we will explore whether dimensionality reduction on environmental variables can improve the predictive performance of SDMs. We first used two linear (i.e., principal component analysis (PCA) and independent components analysis) and two nonlinear (i.e., kernel principal component analysis (KPCA) and uniform manifold approximation and projection) dimensionality reduction techniques (DRTs) to reduce the dimensionality of high‐dimensional environmental data. Then, we established five SDMs based on the environmental variables of dimensionality reduction for 23 real plant species and nine virtual species, and compared the predictive performance of those with the SDMs based on the selected environmental variables through Pearson's correlation coefficient (PCC). In addition, we studied the effects of DRTs, model complexity, and sample size on the predictive performance of SDMs. The predictive performance of SDMs under DRTs other than KPCA is better than using PCC. And the predictive performance of SDMs using linear DRTs is better than using nonlinear DRTs. In addition, using DRTs to deal with environmental variables has no less impact on the predictive performance of SDMs than model complexity and sample size. When the model complexity is at the complex level, PCA can improve the predictive performance of SDMs the most by 2.55% compared with PCC. At the middle level of sample size, the PCA improved the predictive performance of SDMs by 2.68% compared with the PCC. Our study demonstrates that DRTs have a significant effect on the predictive performance of SDMs. Specifically, linear DRTs, especially PCA, are more effective at improving model predictive performance under relatively complex model complexity or large sample sizes.