Selection Of Species Research Articles

Environment-Mediated Vertical Transmission Fostered Uncoupled Phylogenetic Relationships between Longicorn Beetles and Their Symbionts.

The Coleoptera Cerambycidae (longicorn beetles) use wood under different states (living healthy, freshly snapped, completely rot, etc.) in a species-specific manner for their larval diet. Larvae of some Cerambycidae groups have mycetomes, accessory organs associated with the midgut that harbor fungal symbiont cells. The symbionts are thought to improve nutrient conditions; however, this has yet to be shown experimentally. To deduce the evolutionary history of this symbiosis, we investigated the characteristics of the mycetomes in the larvae of longicorn beetles collected in Japan. Lepturinae, Necydalinae, and Spondylidinae are the only groups that possess mycetomes, and these three groups' mycetomes and corresponding fungal cells exhibit different characteristics between the groups. However, the phylogenetic relationship of symbiont yeasts does not coincide with that of the corresponding longicorn beetle species, suggesting they have not co-speciated. The imperfect vertical transmission of symbiont yeasts from female to offspring is a mechanism that could accommodate the host-symbiont phylogenetic incongruence. Some Lepturinae species secondarily lost mycetomes. The loss is associated with their diet choice, suggesting that different conditions between feeding habits could have allowed species to discard this organ. We found that symbiont fungi encapsulated in the mycetomes are dispensable for larval growth if sufficient nutrients are given, suggesting that the role of symbiotic fungi could be compensated by the food larvae take. Aegosoma sinicum is a longicorn beetle classified to the subfamily Prioninae, which does not possess mycetomes. However, this species contains a restricted selection of yeast species in the larval gut, suggesting that the symbiosis between longicorn beetles and yeasts emerged before acquiring the mycetomes.

Key role of plankton species and nutrients on biomagnification of PAHs in the micro-food chain: A case study in plateau reservoirs of Guizhou, China

There is considerable inconsistency in results pertaining to the biomagnification of PAHs in aquatic systems. Zooplankton specifically play an important role controlling the fate and distribution of organic contaminants up the food chain, particularly in large plateau reservoirs. However, it remains largely unknown how secondary factors affect the magnification of organic compounds in zooplankton. The present study assessed plankton species and nutrients affecting the trophic transfer of PAHs through the micro-food chain in plateau reservoirs, Guizhou Province China. Results show soluble ∑PAHs range from 99.9 – 147.3 ng L-1, and concentrations of ∑PAHs in zooplankton range from 1003.2 - 22441.3, with a mean of 4460.7 ng g-1 dw. Trophic magnification factors (TMFs) > 1 show biomagnifications of PAHs from phytoplankton to zooplankton. The main mechanisms for trophic magnification > 1 are 1) small Copepoda, Cladocera and Rotifera are prey for larger N. schmackeri and P. tunguidus, and 2) the δ15N and TLs of zooplankton are increasing with the increasing nutrients TN, NO3- and CODMn. As a result, log PAHs concentrations in zooplankton are positively correlated with the trophic levels (TLs) of zooplankton, and log BAFs of the PAHs in zooplankton are increasing with increasing TLs and log Kow. Temperature further enhances TMFs and biomagnifications of PAHs as noted by temperature related reductions in δ15N. There are also available soluble PAHs in the water column which are assimilated with increasing phytoplankton biomass within the taxa groups, diatoms, dinoflagellates and chlorophytes. Notable TMFs of PAHs in zooplankton in Guizhou plateau reservoirs are not significantly affected by phytoplankton and zooplankton biomass dilutions. The present study demonstrates the important roles of species selection, nutrients and temperature in the environmental fate of PAHs in freshwaters.

Flowering areas enhance insect pollinators and biological control agents in wheat intensive agro‐ecosystems

Abstract This 4‐year study (2018–2021) aimed at investigating the effects of flowering areas inserted at the margin of soft wheat fields (Triticum aestivum L.) in comparison with spontaneous field margins. The action formed part of a multidisciplinary initiative promoted by the Barilla food company, aimed at promoting the sustainable production of soft wheat. Specific aims were to study the effects of flowering areas on (i) the abundance and species richness of insect pollinators, including wild bees, syrphids and butterflies; (ii) the levels of wheat aphid and bug infestations and (iii) the assemblages of biological control agents of aphids (coccinellids and aphid mummies as a result of parasitization). Insect surveys were carried out on 61 wheat‐growing farms located in Northern Italy. Insect pollinators were sampled on all farms, whereas wheat aphids, wheat bugs and aphid biological control agents were investigated in a sub‐sample of 20 farms. Results generally indicated a positive impact of flowering areas on multiple taxa in comparison with spontaneous field margins. The abundance of pollinators and coccinellids was significantly enhanced by the flowering areas. Aphid mummies showed an interaction between strategies and distances with more mummies at 5 m in wheat plots close to flowering areas and at 50 m in the plots close to spontaneous field margin (control). Flowering areas were validated as an important tool for promoting beneficial taxa in agro‐ecosystems. However, the successful establishment of this ecological infrastructure was suggested to rely on several factors, which included both the selection of suitable flowering plant species and the implementation of appropriate management practices.

Constraints of commercially available seed diversity in restoration: Implications for plant functional diversity

Societal Impact StatementLarge quantities of diverse native seeds are required to scale up global restoration efforts. However, it remains unclear for many ecosystems how the diversity of available seed in commercial stocks reflects the composition of the ecosystems where vegetation is being remade. This study highlights existing shortfalls in the diversity of seed presently available for use in restoration and identifies gaps in the seed supply chain while providing a new method for optimising species selection given these constraints. This work underscores how improved collaboration between stakeholders is required to strengthen the seed supply chain and help remake functionally diverse vegetation.Summary Restoration using native seed is frequently implemented to restore degraded ecosystems. However, it remains unclear how constraints on the diversity of germplasm available for use in restoration may limit the recovery of both species and plant functional diversity. Using a dataset of seed availability for Australia's major vegetation types, we explore variation in the diversity and breadth of functional traits (leaf mass per area, seed mass, plant height) for species where seed is available on commercial markets relative to unavailable. Using these data, we simulate theoretical seed mixes derived from two species pools: (1) constrained by the current market of commercially available seed, and (2) assuming all native species can be planted; then we compare differences in functional diversity (dispersion) as an exercise to explore possible limitations within the current seed supply. Seed from only 12% of Australian plant species (2992 species) is presently available for immediate purchase. Seed was more frequently available for trees and shrubs than for understorey species. Available species were on average taller, with thicker, longer‐lived leaves than unavailable species. Overall, functional dispersion was lower for seed mixes generated using available seed compared with those drawn from all species. Solutions are required to address seed shortfalls so that plantings are not only species rich but also functionally diverse. We develop two options: (1) quantifying and addressing gaps in the seed supply chain that currently limit the capacity for practitioners to restore diverse vegetation; and (2) applying a trait‐informed species‐selection method to plantings that maximises functional diversity using available seed.

Spatial Variation of Airborne Pollen Concentrations Locally around Brussels City, Belgium, during a Field Campaign in 2022–2023, Using the Automatic Sensor Beenose

As a growing part of the world population is suffering from pollen-induced allergies, increasing the number of pollen monitoring stations and developing new dedicated measurement networks has become a necessity. To this purpose, Beenose, a new automatic and relatively low-cost sensor, was developed to characterize and quantify the pollinic content of the air using multiangle light scattering. A field campaign was conducted at four locations around Brussels, Belgium, during summer 2022 and winter–spring 2023. First, the consistency was assessed between the automatic sensor and a collocated reference Hirst-type trap deployed at Ixelles, south-east of Brussels. Daily average total pollen concentrations provided by the two instruments showed a mean error of about 15%. Daily average pollen concentrations were also checked for a selection of pollen species and revealed Pearson and Spearman correlation coefficients ranging from 0.71 to 0.93. Subsequently, a study on the spatial variability of the pollen content around Brussels was conducted with Beenose sensors. The temporal evolution of daily average total pollen concentrations recorded at four sites were compared and showed strong variations from one location to another, up to a factor 10 over no more than a few kilometers apart. This variation is a consequence of multiple factors such as the local vegetation, the wind directions, the altitude of the measurement station, and the topology of the city. It is therefore highly necessary to multiply the number of measurement stations per city for a better evaluation of human exposure to pollen allergens and for more enhanced pollen allergy management.

Genomic Gigantism is not Associated with Reduced Selection Efficiency in Neotropical Salamanders

Genome size variation in eukaryotes has myriad effects on organismal biology from the genomic to whole-organism level. Large genome size may be associated with lower selection efficiency because lower effective population sizes allow fixation of deleterious mutations via genetic drift, increasing genome size and decreasing selection efficiency. Because of a hypothesized negative relationship between genome size and recombination rate per base pair, increased genome size could also increase the effect of linked selection in the genome, decreasing the efficiency with which natural selection can fix or remove mutations. We used a transcriptomic dataset of 15 and a subset of six Neotropical salamander species ranging in genome size from 12 to 87 pg to study the relationship between genome size and efficiency of selection. We estimated dN/dS of salamanders with small and large genomes and tested for relaxation of selection in the larger genomes. Contrary to our expectations, we did not find a significant relationship between genome size and selection efficiency or strong evidence for higher dN/dS values in species with larger genomes for either species set. We also found little evidence for relaxation of selection in species with larger genomes. A positive correlation between genome size and range size (a proxy of population size) in this group disagrees with predictions of stronger drift in species with larger genomes. Our results highlight the complex interactions between the many forces shaping genomic variation in organisms with genomic gigantism.

Comparison of nectar and pollen resources in various Tilia species. A case study from southern Poland

Management of food resources is considered fundamental for supporting insect pollinators, whose abundance shows a downward trend on the global scale. Here, the nectar and pollen production (per flower, per 1 m2 of tree crown), the composition of nectar carbohydrates and the levels of pollen proteins was evaluated in eight Tilia species (Malvaceae) growing in SE Poland. In the warm-summer continental climate, Tilia species can improve nectar and pollen resources mainly in June/July. Although the flowering period of each species is short (8.0–14.7 days), appropriate selection of species can extend the availability of food for more than a month. However, the considerable variations in the flowering onset (11.2–20.1 days) may cause significant inter-seasonal shifts in food accessibility.The nectar with its highly changeable sugar concentration (29.5–77.4%) was composed of sucrose, glucose, and fructose; protein content in pollen was 7.2–16.8%. The mean sugar yield was in the range of 0.95–19.1 g per 1 m2 (T. amuriensis – T. platyphyllos, respectively), whereas the mean pollen yield was 1.37–4.1 g per 1 m2 of tree crown (T. amuriensis – T. × euchlora, respectively). Significant year-to-year fluctuations of sugar and pollen yield in linden trees have to be taken into account in conservation schemes, and the introduction of other flowering plants with more stable sugar and pollen production should be considered in an area with a high density of linden trees. Linden flowers mainly support honey bees; nevertheless, wild pollinators (bumble bees, solitary bees, and dipterans) can also benefit from linden floral resources.

Selection of Eucalyptus Tree Species and Soil Management Suitable for the Environment of Southern South Korea

Selection of Eucalyptus Tree Species and Soil Management Suitable for the Environment of Southern South Korea

Exploring tolerance mechanisms and root morphological development of New Zealand spinach and quinoa across salinity levels

Soil salinity, root sodium concentration, and transpiration rate are important environmental factors impacting plant growth and productivity. This study investigates the salt-coping strategies of two plant species under varying salinity levels: New Zealand spinach species grown at three salinity levels (i.e., 0, 100, and 200 mM NaCl) and three varieties of quinoa, i.e., “Vikinga”, “Dave 407” and “Red Head”, grown with or without salt (i.e., 0 and 100 mM NaCl). The plants were grown on glass fiber sheets (rhizoslides) under controlled laboratory conditions. The relationship between transpiration rate, salinity, and root architecture was analyzed for each species. The root apparatus of New Zealand spinach was significantly more developed in plants grown at 100 mM NaCl compared to both 200 mM NaCl and control. The quinoa varieties responded differently to the increasing salt concentrations, with salt-treated “Red Head” plants significantly reducing their total root length and salt-treated “Vikinga” significantly reducing its lateral roots compared to the controls. Salt concentration near New Zealand spinach roots was lower compared to areas without roots, suggesting active salt uptake. In contrast, quinoa rhizoslides exhibited higher salt concentration in proximity to the roots, indicative of salt exclusion. The study provides insights into the adaptation and tolerance mechanisms of these two species to salinity, elucidating the mechanisms by which plants regulate their sodium uptake and root growth. The obtained results suggest that not only the selection of appropriate plant species (halophytes), but also varieties, plays a crucial role in improving crop productivity in salt-affected areas. Elucidating the salt-coping mechanisms of halophytes in relation to soil and climatic conditions is important to better predict their behavior in various saline environments.

Revealing the Mechanism of Combining Best Properties of Homogeneous and Heterogeneous Catalysis in Hybrid Pd/NHC Systems

AbstractThe formation of transient hybrid nanoscale metal species from homogeneous molecular precatalysts has been demonstrated by in situ NMR studies of catalytic reactions involving transition metals with N‐heterocyclic carbene ligands (M/NHC). These hybrid structures provide benefits of both molecular complexes and nanoparticles, enhancing the activity, selectivity, flexibility, and regulation of active species. However, they are challenging to identify experimentally due to the unsuitability of standard methods used for homogeneous or heterogeneous catalysis. Utilizing a sophisticated solid‐state NMR technique, we provide evidence for the formation of NHC‐ligated catalytically active Pd nanoparticles (PdNPs) from Pd/NHC complexes during catalysis. The coordination of NHCs via C(NHC)−Pd bonding to the metal surface was first confirmed by observing the Knight shift in the 13C NMR spectrum of the frozen reaction mixture. Computational modeling revealed that as little as few NHC ligands are sufficient for complete ligation of the surface of the formed PdNPs. Catalytic experiments combined with in situ NMR studies confirmed the significant effect of surface covalently bound NHC ligands on the catalytic properties of the PdNPs formed by decomposition of the Pd/NHC complexes. This observation shows the crucial influence of NHC ligands on the activity and stability of nanoparticulate catalytic systems.

Revealing the Mechanism of Combining Best Properties of Homogeneous and Heterogeneous Catalysis in Hybrid Pd/NHC Systems.

The formation of transient hybrid nanoscale metal species from homogeneous molecular precatalysts has been demonstrated by in situ NMR studies of catalytic reactions involving transition metals with N-heterocyclic carbene ligands (M/NHC). These hybrid structures provide benefits of both molecular complexes and nanoparticles, enhancing the activity, selectivity, flexibility, and regulation of active species. However, they are challenging to identify experimentally due to the unsuitability of standard methods used for homogeneous or heterogeneous catalysis. Utilizing a sophisticated solid-state NMR technique, we provide evidence for the formation of NHC-ligated catalytically active Pd nanoparticles (PdNPs) from Pd/NHC complexes during catalysis. The coordination of NHCs via C(NHC)-Pd bonding to the metal surface was first confirmed by observing the Knight shift in the 13C NMR spectrum of the frozen reaction mixture. Computational modeling revealed that as little as few NHC ligands are sufficient for complete ligation of the surface of the formed PdNPs. Catalytic experiments combined with in situ NMR studies confirmed the significant effect of surface covalently bound NHC ligands on the catalytic properties of the PdNPs formed by decomposition of the Pd/NHC complexes. This observation shows the crucial influence of NHC ligands on the activity and stability of nanoparticulate catalytic systems.

A Review Delving into the Factors Influencing Mycelium-Based Green Composites (MBCs) Production and Their Properties for Long-Term Sustainability Targets.

Mycelium-based green composites (MBCs) represent an eco-friendly material innovation with vast potential across diverse applications. This paper provides a thorough review of the factors influencing the production and properties of MBCs, with a particular focus on interdisciplinary collaboration and long-term sustainability goals. It delves into critical aspects such as fungal species selection, substrate type selection, substrate preparation, optimal conditions, dehydrating methods, post-processing techniques, mold design, sterilization processes, cost comparison, key recommendations, and other necessary factors. Regarding fungal species selection, the paper highlights the significance of considering factors like mycelium species, decay type, hyphal network systems, growth rate, and bonding properties in ensuring the safety and suitability of MBCs fabrication. Substrate type selection is discussed, emphasizing the importance of chemical characteristics such as cellulose, hemicellulose, lignin content, pH, organic carbon, total nitrogen, and the C: N ratio in determining mycelium growth and MBC properties. Substrate preparation methods, optimal growth conditions, and post-processing techniques are thoroughly examined, along with their impacts on MBCs quality and performance. Moreover, the paper discusses the importance of designing molds and implementing effective sterilization processes to ensure clean environments for mycelium growth. It also evaluates the costs associated with MBCs production compared to traditional materials, highlighting potential cost savings and economic advantages. Additionally, the paper provides key recommendations and precautions for improving MBC properties, including addressing fungal strain degeneration, encouraging research collaboration, establishing biosecurity protocols, ensuring regulatory compliance, optimizing storage conditions, implementing waste management practices, conducting life cycle assessments, and suggesting parameters for desirable MBC properties. Overall, this review offers valuable insights into the complex interplay of factors influencing MBCs production and provides guidance for optimizing processes to achieve sustainable, high-quality composites for diverse applications.

Current understanding and knowledge gaps regarding wildlife as reservoirs of antimicrobial resistance.

Antimicrobial resistance (AMR) is a serious health issue shared across all One Health domains. Wildlife species represent a key intersection of the animal and environmental domains. They are a relevant but understudied reservoir and route of spread for AMR throughout the environment. Most wildlife AMR research thus far has focused on avian species, terrestrial mammals, and a selection of aquatic and marine species. Pathogens often identified in terrestrial wildlife include enteric zoonotic organisms such as Eschericia coli and Salmonella spp, in addition to nonenterics such as Staphylococci. Resistances have been commonly identified to antimicrobials important in veterinary and human medicine, including β-lactams, tetracyclines, aminoglycosides, and macrolides. Our emerging understanding of the dynamics of AMR distribution across life on Earth provides further opportunities for us to assess the risk it poses to veterinary and human health. Future work will require prioritizing which wildlife most exacerbates and indicates AMR in domestic animals. However, decreasing prices and increasing ease for metagenomic sequencing allows for synergies with expanding wildlife viral disease surveillance. Improved understanding of how wildlife impacts veterinary and human healthcare may increase opportunities for related research funding and global equity in such research. The companion Currents in One Health article by Vezeau and Kahn, JAVMA, June 2024, addresses in further detail the routes of spread of AMR across different animal populations and actions that can be taken to mitigate AMR with special consideration for wildlife sources.

Early impacts of cover crop selection on soil biological parameters during a transition to organic agriculture

AbstractAlthough Texas is not widely known for organic production, it is responsible for most organic peanut production in the United States. When managed effectively, this can be a lucrative practice due to consumer demands. However, farmers pursuing organic management must undergo a 3‐year transition period to obtain United States Department of Agriculture certification, which is often associated with depressed yields. The objective of this study was to measure the impact of organic management and cover crop selection on biological indicators of soil health during the second year of transitioning to an organic cotton–peanut rotation in West Texas. We conducted a field study at two locations, and soil health indicators including in situ respiration, carbon mineralization, enzyme activities, and phospholipid fatty acids (PLFAs) were measured. The use of a cover crop resulted in generally greater biological activities compared to the fallow after only one cover crop rotation, representing early elevated biological activities under plots treated with a cover crop. However, cover crop species selection typically does not affect soil biological parameters. Cover crop use also did not contribute to yield losses when compared to a fallow treatment. When comparing organic management to conventional management, both sites experienced elevated PLFA counts under organic management. Importantly, results indicated that although reduced peanut yields could be expected under transitional organic management, this was not cover crop species‐specific, nor was it a guarantee. Given the economic risk of organic management for farmers, this study will benefit producers deciding whether to pursue organic production and cover cropping.

Moss Bags as Active Biomonitors of Air Pollution: Current State of Understanding, Applications and Concerns

Dual concerns involving the rise in airborne pollutant levels and bulging need to protect-preserve human health have propelled the search for innovative means for air quality monitoring to aid in evidence-based decision-making (pollution prevention-mitigation). In this regard, moss bags have gathered a great deal of attention as active biomonitors. In this reflective discourse, we systematically review the world literature to present a bird’s eye view of moss bag applications and advances while highlighting potential concerns. We begin with a brief note on mosses as biomonitors, highlighting the advantages of moss bags over the passive technique (native moss), other living organisms (lichens, vascular plants), and instrument-based measurements. A major strand of moss bag research involves urban ecosystem sustainability studies (e.g., street tunnels and canyons, parks), while others include event-specific monitoring and change detection (e.g., SARS-CoV-2 Lockdown), indoor-outdoor air quality assessment, and change detection in land use patterns. Recent advances include biomagnetic studies, radioisotopic investigations, and mobile applications. Efforts are currently underway to couple moss bag results with a suite of indicators [e.g., relative accumulation factor (RAF), contamination factor (CF), pollution load index (PLI), enrichment factor (EF)] and spatially map the results for holistic appraisal of environmental quality (hot spot detection). However, while moss bag innovations and applications continue to grow over time, we point to fundamental concerns/uncertainties (e.g., lack of concordance in operational procedures and parameterization, ideal species selection, moss vitality) that still need to be addressed by targeted case studies, before the moss results could be considered in regulatory interventions.

Response of Microbial Communities to Naturally Occurring Radioactive Material-Contaminated Sediments: A Microcosm-Based Study.

There is a growing need to understand the potential ecological impacts of contaminants in offshore oil and gas infrastructure, especially if that infrastructure is to be left in situ as a decommissioning option. Naturally occurring radioactive material (NORM) is one type of contaminant found in solid deposits on internal surfaces of infrastructure that poses potential ecological harm if released into the marine environment. Microbes are important components of marine sediment ecosystems because they provide ecosystem services, yet the impacts of NORM contamination to these communities are not well understood. The present study aimed to investigate the response of benthic microbial communities to NORM-contaminated scale, collected from an offshore oil and gas system, via controlled laboratory microcosm studies. Changes to microbial communities in natural sediment and sediments spiked with NORM at radium-226 activity concentrations ranging from 9.5 to 59.8 Bq/kg (in partial equilibria with progeny) over 7 and 28 days were investigated using high-throughput sequencing of environmental DNA extracted from experimental sediments. There were no significant differences in microbial community composition between control and scale-spiked sediments over 7 and 28 days. However, we observed a greater presence of Firmicutes in the scale-mixed treatment and Chloroflexi in the scale-surface treatments after 28 days. This could suggest selection for species with contaminant tolerance or potential resilience to radiation and metal toxicity. Further research is needed to explore microbial tolerance mechanisms and their potential as indicators of effects of radionuclide-contaminated sediments. The present study demonstrated that microcosm studies can provide valuable insights about the potential impacts of contamination from oil and gas infrastructure to sediment microbial communities. Environ Toxicol Chem 2024;43:1648-1661. © 2024 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.

Comparisons of Different Representative Species Selection Schemes for Reduced-Order Modeling and Chemistry Acceleration of Complex Hydrocarbon Fuels

The simulation of engine combustion processes, such as autoignition, an important process in the co-optimization of fuel-engine design, can be computationally expensive due to the large number of thermo-chemical scalars needed to describe the full chemical system. Yet, the inherent correlations between the different chemical species during oxidation can significantly reduce the complexity of representing this system. One strategy is to select a subset of representative species that accurately captures the combustion process at a fraction of the computational cost of the full system. In this study, we compare the performance of four different techniques to select these species. They include the two-step principal component analysis (PCA) approach, directed relation graphs (DRGs), the global pathway selection (GPS) approach, and the manifold-informed species selection method. A parametric study of the representative species selection is carried out on data from the simulation of homogeneous and perfectly stirred reactors by investigating seven cumulative variances and 47 different cut-off percentages for the two-step PCA, and 65 and 51 thresholds for the DRGs and GPS, respectively. Results show that these selection methods capture key important species that can accurately describe the chemical system and track each stage of oxidation. The two-step PCA is sensitive to the cumulative variance, and DRGs and GPS are sensitive to the choice of target variables. By selecting key representative species and reducing the number of thermo-chemical scalars, these three methods can be used to develop computationally efficient hybrid chemistry schemes.

Plant beta-turnover rather than nestedness shapes overall taxonomic and phylogenetic beta-diversity triggered by favorable spatial-environmental conditions in large-scale Chinese grasslands.

Although it is widely acknowledged that biodiversity maintains plant community assembly processes, exploring the patterns and drivers of beta-diversity (β-diversity; species variation among local plant communities) has received much less attention compared to alpha-diversity (α-diversity; species variation within a local plant community). Here, we aim to examine the patterns and spatial-environmental drivers of taxonomic and phylogenetic β-diversity, and their components such as species turnover and nestedness, in large-scale Leymus chinensis grassland communities. We collected plant community data from 166 sites across widely distributed L. chinensis communities in northern China, and then calculated the taxonomic and phylogenetic β-diversity indices (overall, turnover and nestedness) using a pairwise dissimilarity approach. To assess the effects and to explain the variation in the patterns of β-diversity, we collected data on geospatial, climate and soil conditions. We applied descriptive statistics, Mental correlations, and multiple linear regression models to assess the patterns and spatial-environmental drivers of β-diversity. The β-turnover, as compared to β-nestedness, exhibited a predominant influence, constituting 92.6% of the taxonomic β-diversity and 80.4% of the phylogenetic β-diversity. Most of the spatial-environmental variables were significantly positively correlated with the overall taxonomic and phylogenetic β-diversity and β-turnover, but not with β-nestedness. Climatic factors such as MAP and MAT were the strongest predictors of both taxonomic and phylogenetic β-diversity and β-turnover. The variance partitioning analysis showed that the combined effects of spatial and environmental factors accounted for 19% and 16% of the variation in the taxonomic and phylogenetic β-diversity (overall), 17% and 12% of the variation in the β-turnover, and 7% and 1% of the variation in the β-nestedness, respectively, which were higher than independent effects of either spatial or environmental factors. At larger spatial scales, the turnover component of β-diversity may be associated with the species complementarity effect, but dominant or functionally important species can vary among communities due to the species selection effect. By incorporating β-diversity into grassland management strategies, we can enhance the provision of vital ecosystem services that bolster human welfare, serving as a resilient barrier against the adverse effects of climate change at regional and global scales.

Leveraging climate and remote sensing metrics for predicting forest carbon stock using Bayesian geostatistical modelling under a projected climate warming in Zimbabwe

Climate change, driven by escalating carbon dioxide (CO2) emissions, poses a significant threat to forest ecosystems and the livelihoods of communities reliant on them, especially for the global south countries and regions like the eastern highlands of Zimbabwe. The 2000 land redistribution programme reduced buffer zones between ecologically sensitive forests and land reform beneficiaries near major carbon reservoirs. In light of these challenges, this study aimed to assess the potential effects of climate change on a strategically important plantation forest ecosystem in Zimbabwe's eastern highlands. Using data from the Coupled Model Inter-comparison Project Phase 6 (CMIP6) of the Intergovernmental Panel on Climate Change (IPCC), we modelled and predicted changes in forest carbon (C) stock density under different climate scenarios: current (1970–2000), SSP5–4.5, and SSP5–8.5. Employing a hierarchical Bayesian geostatistical approach, we compared the baseline scenario (1970–2000) with projected scenarios (RCP4.5 and RCP8.5) for 2075 to estimate changes in forest carbon stock distribution. Our results indicated a decline in carbon stock concentration under future climate scenarios, reflecting the adverse impact of greenhouse gas emissions on forest growth. We found that the projected range of forest carbon stock under the RCP8.5 scenario for 2075 is notably lower (2≤MgCha−1≤44.9) than that of the baseline period (1970–2000) (1≤MgCha−1≤97), suggesting a substantial reduction in carbon storage. As the difference in posterior mean C stock (μ̅1−μ̅2), 52.1 MgCha-1 is well above zero, we deduce that the posterior mean C stock distribution of the projected future RCP8.5 2075 climate projection is indeed credibly different from the current (1970–2000) climate scenario. Additionally, there is a high probability (>90%) that forest plantations will be adversely affected by the business-as-usual climate warming projection. Overall, our findings highlight the urgent need for climate change mitigation strategies, such as reforestation programs and careful selection of tree species for plantations, to safeguard forest ecosystems and the communities dependent on them. These insights are crucial for informing effective adaptation measures in the face of future climate uncertainties.

Unraveling the characteristic spatial scale of habitat selection for forest grouse species in the boreal landscape

The characteristic spatial scale at which species respond strongest to forest structure is unclear and species-specific and depends on the degree of landscape heterogeneity. Research often analyzes a pre-defined spatial scale when constructing species distribution models relating forest variables with occupancy patterns. This is a limitation, as forest characteristics shape the species use of habitat at multiple spatial scales. To explore the drivers of this relationship, we conducted an in-depth investigation into how scaling forest variables at biologically relevant spatial scales affects occupancy of grouse species in boreal forest. We used 4,790 grouse observations (broods and adults) collected over 39,303 stands for 15 years of four forest grouse species (capercaillie, black grouse, hazel grouse, and willow grouse) obtained from comprehensive Finnish wildlife triangle census data and forest variables obtained from Airborne Laser Scanning and satellite data originally sampled at 16 m resolution. We fitted Generalized Additive Mixed Models linking grouse presence/absence in the Finnish boreal forest with forest stand structure and composition. We estimated the effects of predictor variables aggregated at three spatial scales reflecting the species use of the landscape: local level at stand scale, home range level at 1 km radius, and regional level at 5 km radius. Multi-grain models considering forest-species relationships at multiple scales were used to evaluate whether there is a specific scale at which forest characteristics best predict local grouse occupancy. We found that that the spatial scale affected the predictive capacity of the grouse occupancy models and the characteristic scale of habitat selection was the same (i.e., stand scale) among species. Different grouse species exhibited varying optimal spatial scales for occupancy prediction. Forest structure was more important than compositional diversity in predicting grouse occupancy irrespective of the scale. A limited number of forest predictors related to availability of multi-layered vegetation and of suitable thickets explained the occupancy patterns for all the grouse species at different scales. In conclusion, modeling grouse occupancy using forest predictors at different spatial scales can inform forest managers about the scale at which the species perceive the landscape. This evidence calls for an integrated multiscale approach to habitat modelling for forest species.