Variation In Biodiversity Research Articles

Biodiversity of urban green spaces and human health: a systematic review of recent research

Although recent studies have explored links between landscape biodiversity and human health, the exact effects of specific types of biodiversity—such as the variety of species or genera—on health outcomes are still uncertain. In this review, we evaluate our current knowledge of how landscape biodiversity influences human health in different cultural contexts. We systematically assessed peer-reviewed literature to: 1) summarize the links between biodiversity variability and human health outcomes; 2) describe the pathways used to examine these links; 3) compare subjective perceptions of biodiversity with objective measures; and 4) describe any known connections between perceived biodiversity and health outcomes. We analyzed 41 studies published between 2018 and 2023, covering research from 15 countries on five continents. A key finding was the lack of significant links between biodiversity variability, like species richness, and health outcomes; only one-third of studies reported positive health effects. We identified two main pathways: restoring health capacities (mental health) and building health capacities (physical health). The public could identify different biodiversity levels, with perceived biodiversity correlating with health. Future research should explore varied mechanisms, physical health outcomes, causal relationships, and effects across diverse populations and regions.

Biodiversity from the Sky: Testing the Spectral Variation Hypothesis in the Brazilian Atlantic Forest

Tropical forests have high species richness, being considered the most diverse and complex ecosystems in the world. Research on the variation and maintenance of biodiversity in these ecosystems is important for establishing conservation strategies. The main objective of this study was to test the Spectral Variation Hypothesis through associations between species diversity and richness measured in the field and hyperspectral data collected by a Remotely Piloted Aircraft (RPA) in areas with secondary tropical forest in the Brazilian Atlantic Forest biome. Specific objectives were to determine which dispersion measurements, standard deviation (SD) or coefficient of variation (CV), estimated for the n pixels occurring within each sampling unit, better explains species diversity; the effects of pixel size on the direction and intensity of this relationship; and the effects of shaded pixels within each sampling unit. The spectral variability hypothesis was confirmed for the Atlantic Forest biome, with R2 of 0.83 for species richness and 0.76 and 0.69 for the Shannon and Simpson diversity indices, respectively, using 1.0 m illuminated pixels. The dispersion (CV and SD) of hyperspectral bands were most strongly correlated with taxonomic diversity and richness in the red-edge and near-infrared (NIR) regions of the electromagnetic spectrum. Pixel size affected R2 values, which were higher for 1.0 m pixels (0.83) and lower for 10.0 m pixels (0.71). Additionally, illuminated pixels had higher R2 values than those under shadow effects. The main dispersion variables selected as metrics for regression models were mean CV, CV for the 726.7 nm band, and SD for the 742.3 and 933.4 nm bands. Our results suggest that spectral diversity can serve as a proxy for species diversity in the Atlantic Forest. However, factors that can affect this relationship, such as taxonomic and spectral diversity metrics used, pixel size, and shadow effects in images, should be considered.

30 years of terrestrial insect richness patterns across elevation: What have we learned? A global meta-analysis.

Understanding elevation variation in biodiversity is a classic question in ecology and has implications for understanding climate change impacts on mountain ecosystems. While insects are the largest group of animals, the global trend in insect species richness with elevation is unknown. To date, single studies and taxa-specific syntheses have provided no single picture, finding variable patterns of insect richness with elevation. A global synthesis across systems would provide a better understanding of how insect species richness changes with elevation and the possible environmental correlates of those patterns. We used published studies of terrestrial insect elevation gradients from 1990 to 2020 to ask: How do insect species richness change with elevation, and which environmental variables best explain this relationship statistically? With 1486 sites spanning 151 species richness-elevation gradients from 80 studies from four diverse insect taxonomic groups and five biomes, we found that overall proportional richness reached a low-elevation plateau and then decreased. We also show that mean annual temperature and seasonality best explain this trend. We suggest best practices and areas of interest for the future of insect richness-elevation studies, including underrepresented groups, geographic areas, and more standardized methods.

Perbandingan Komposisi dan Struktur Komunitas Makroalga antara Pulau Semak Daun dan Pulau Pramuka di Taman Nasional Kepulauan Seribu, DKI Jakarta

Kepulauan Seribu have diverse biodiversity, one of which is macroalgae located in the Tourism Utilization Zone and the residential zone. Environmental factors, such as substrate, water quality and the presence of human activities, are very different on each island. The purpose of this study was to determine the differences in the composition and structure of macroalgae communities on islands in the Tourism Utilization Zone, Semak Daun Island and islands in the Settlement Zone, Pramuka Island. Settlement Zone, Pramuka Island. The method used is a quadrat transect. 16 types of macroalgae were found on Semak Daun Island and 26 types of macroalgae on Pramuka Island. The diversity value on Semak Daun Island is categorized as moderate with a value of 1.84 and on Pramuka Island is categorized as moderate with a value of 2.64. The highest INP value on Semak Daun Island is Sargassum binderi and the highest INP on Pramuka Island is Halimeda macroloba.

Decadal variation and temporal stability of the macrobenthic community in the Bohai Sea, China

Biodiversity in the Bohai Sea is threatened by climate change and human activities. An analysis based on decadal macrobenthic community data was conducted to assess the ecological health. These findings revealed the temporal and spatial variations in species composition and biodiversity, which were primarily influenced by depth, temperature and dissolved oxygen content. The community structure in 2014 exhibited a 70 % dissimilarity compared to other years, and biodiversity was lower in 2014. The dominant species showed a trend towards miniaturization. Abundance-biomass comparison curves indicated that community disturbance improved by implementing various policies. Overall, communities in the Bohai Sea remained stable, except in the Bohai Strait (BH), where synchronous fluctuations with an increasing trend were observed. Enhancing biodiversity and addressing the risks associated with losing single species are essential for maintaining community stability. The community also displayed synchronous tendencies in Laizhou Bay, emphasizing the need for continued long-term monitoring.

The Interaction between Climate Change and Biodiversity Can Be Assessed from a Material Cycle Perspective

This study focused on understanding biodiversity variability in response to climate change as an environmental stressor from a carbon cycle perspective. As the frequency and magnitude of environmental stresses are expected to increase due to rising carbon concentrations, these changes may affect the variability in biodiversity. However, several studies have argued that conventional methods for biodiversity assessment, primarily based on arithmetic indices utilized in national policies, are inadequate for accurately assessing these interactions among species, abiotic changes, and material cycling. Here, we indicate that environmental stressors that occur at various scales and domains, from macroscopic to microscopic, and their effects on ecosystems are multi-dimensional. Furthermore, environmental stresses not only affect organisms inhabiting these ecosystems but these organisms, in return, influence the carbon cycle through life history changes resulting from these stresses. The results of our review suggest that these processes are sequentially interconnected, forming self-reinforcing feedback loops. Ultimately, an integrated approach is necessary to understand biodiversity variability in complex and open ecosystems. This approach should be capable of comprehending changes in the overall flow by considering ecosystem characteristics.

Processes regulating local community assembly of plants and spiders in high latitude mountains

AbstractAimMountains are often used to study how environmental factors influence biodiversity. However, we have limited understanding of the processes causing biodiversity variation in mountains and whether such processes vary across trophic levels and spatial scales. The aim of this study was to evaluate (i) whether community assembly processes varied along elevational gradients, (ii) whether there were differences in such variation between primary producers (vascular plants) and secondary consumers (spiders) and (iii) whether there were scale dependencies in any elevational variation in community assembly.LocationFennoscandia, Northern Sweden.TaxonVascular plants, spiders.MethodsWe used phenotypic and phylogenetic dispersion to quantify how elevation influenced community assembly of vascular plants and spiders and whether there were any scale dependencies in such influences. Our original data of plant and spider communities came from our own field surveys, phenotypic dispersion was calculated based on matrices of ecological traits, and phylogenetic dispersion was calculated from phylogenetic trees for each organism group. Trait matrices were based on a combination of literature values and our own measurements. The phylogeny for vascular plants was based on a published plant super‐tree, whereas the phylogeny for spiders was created by ourselves based on the DNA sequences at the mitochondrial cytochrome c oxidase subunit 1 (COI).ResultsPlants were environmentally filtered throughout all elevations and scales, but the importance of convergent evolution increased with elevation. For spiders, the importance of environmental filtering as well as niche conservatism increased with elevation. For both groups, communities at smaller scales were more influenced by biotic regulation and niche conservatism than at larger scales.Main ConclusionsOur study highlights both taxonomic differences and scale dependencies in how elevation influences community assembly. We argue that these results can have broad ramifications for our understanding of how spatial variation in biodiversity is generated and maintained. This may have particular relevance for our ability to predict the ecological consequences of climate change. Our results further highlight that high elevation specialists may suffer increased risks of climate driven extinctions due to a combination of increased competition and increased fragmentation of suitable habitats. Particularly for spiders, which had high elevation specialists clustered along specific lineages, such extinctions could lead to significant loss of phylogenetic variation.

The joint effects of local, climatic, and spatial variables determine soil oribatid mite community assembly along a temperate forest elevational gradient.

Numerous factors influence mountain biodiversity variation across elevational gradients and recognizing the relative importance is vital for understanding species distribution mechanisms. We examined oribatid mites at nine elevations (from 600 to 2200 m a.s.l) and four vegetation types from mixed coniferous and broad-leaved forests to alpine tundra on Changbai Mountain. We assessed the contribution of environmental factors (climatic and local factors) and spatial processes (geographic or elevation distances) to oribatid mite community assembly and identified 59 oribatid mite species from 38 families and 51 genera. With increasing elevation, species richness and the Shannon index declined significantly, whereas abundance followed a hump-shaped trend. Soil TP, NH4 +-N, MAT, MAP, and elevation were the critical variables shaping oribatid mite communities based on random forest analysis. Moreover, environmental and spatial factors, and oribatid mite communities were significantly correlated based on Mantel and partial Mantel tests. Local characteristics (3.9%), climatic factors (1.9%), and spatial filtering (8.8%) played crucial roles in determining oribatid mite communities across nine elevational bands (based on variation partitioning analyses of abundance data). Within the same vegetation types, spatial processes had relatively little effects, with local characteristics the dominant drivers of oribatid mite community variation. Environmental and spatial filters together shape oribatid mite community assembly and their relative roles varied with elevation and vegetation type. These findings are crucial for the conservation, restoration, and management of Changbai mountain ecosystems in the context of climate change, along with the prediction of future vertical biotic gradient pattern evolution.

Multi-taxon species richness representation within national nature reserves is associated with spatial features, human disturbance and environmental factors in mountains region

The Humboldt’s enigma has continued for many centuries, A multitude of studies have delved into various potential reasons for this richness—from topography and climate to community succession—yet a singular, all-encompassing theory for species richness across multiple taxa in mountain ecosystems remains elusive. In this research, we explored the causes of species richness in mountain multiple-taxa in terms of spatial attributes of protected areas, human disturbance and environmental factors. Initiating our study, we compiled a comprehensive database of all national nature reserves (NNRs) situated in the karst regions of Guizhou province. This was achieved through an extensive multidisciplinary field survey in recent years, resulting in a collection of 40,570 species records. Subsequently, we discerned a complex interplay between species richness, spatial attributes, human disturbance, and environmental factors, which collectively account for over 80 % of the observed variations in mountain biodiversity. Our findings revealed several intricate relationships: Shape index and fragmentation positively influenced the richness of insect, animal, and seed plant species. Conversely, anthropogenic alterations and nighttime light negatively impacted the diversity of amphibians, reptiles, and mammals. Interestingly, we discovered a significant positive association between the richness of fungi, mosses, and ferns and the variables of soil texture and soil water, demonstrating the importance of soils in karst for maintaining biodiversity. To conclude, we evaluated conservation strategies in mountainous regions. It is imperative that the spatial configuration of protected areas be refined to alleviate the detrimental effects of human disturbance. Furthermore, conservation efforts should be customized to the unique climatic and geographic conditions found locally.

Wetland biodiversity in Aotearoa New Zealand: an eDNA perspective on exotic and non-exotic species

ABSTRACT Invasive species threaten biodiversity in Aotearoa New Zealand. In wetlands − significant sites that provide an array of ecosystem and cultural services but represent <10% of their original extent − invasive species can affect hydrological function, nutrient regimes and overall ecological functionality. Environmental DNA (eDNA) has emerged as a valuable biomonitoring technique for cataloguing biodiversity and detecting biological incursions, but little is known about how biodiversity varies in wetlands over fine and broad spatial scales. Here, we examined the publicly available eDNA database of Wilderlab New Zealand, retrieving data from 26 sites across the country to characterise taxonomic diversity patterns, including the extent of exotic and non-exotic (native and endemic) species. We found significant spatial variation in biodiversity – even among neighbouring sites – and a pattern whereby all sites had ≥50% exotic species in their total species tally. Our results provide new information on the current state of wetland biodiversity in Aotearoa New Zealand and highlight the value of eDNA databases for generating new insights from publicly shared data. They also emphasise an urgent need for greater resource allocation to conservation and restoration initiatives in Aotearoa New Zealand that will ensure the persistence of treasured native and endemic wetland species.

Effects of spatial variability in vegetation phenology, climate, landcover, biodiversity, topography, and soil property on soil respiration across a coastal ecosystem

Coastal terrestrial-aquatic interfaces (TAIs) are crucial contributors to global biogeochemical cycles and carbon exchange. The soil carbon dioxide (CO2) efflux in these transition zones is however poorly understood due to the high spatiotemporal dynamics of TAIs, as various sub-ecosystems in this region are compressed and expanded by complex influences of tides, changes in river levels, climate, and land use. We focus on the Chesapeake Bay region to (i) investigate the spatial heterogeneity of the coastal ecosystem and identify spatial zones with similar environmental characteristics based on the spatial data layers, including vegetation phenology, climate, landcover, diversity, topography, soil property, and relative tidal elevation; (ii) understand the primary driving factors affecting soil respiration within sub-ecosystems of the coastal ecosystem. Specifically, we employed hierarchical clustering analysis to identify spatial regions with distinct environmental characteristics, followed by the determination of main driving factors using Random Forest regression and SHapley Additive exPlanations. Maximum and minimum temperature are the main drivers common to all sub-ecosystems, while each region also has additional unique major drivers that differentiate them from one another. Precipitation exerts an influence on vegetated lands, while soil pH value holds importance specifically in forested lands. In croplands characterized by high clay content and low sand content, the significant role is attributed to bulk density. Wetlands demonstrate the importance of both elevation and sand content, with clay content being more relevant in non-inundated wetlands than in inundated wetlands. The topographic wetness index significantly contributes to the mixed vegetation areas, including shrub, grass, pasture, and forest. Additionally, our research reveals that dense vegetation land covers and urban/developed areas exhibit distinct soil property drivers. Overall, our research demonstrates an efficient method of employing various open-source remote sensing and GIS datasets to comprehend the spatial variability and soil respiration mechanisms in coastal TAI. There is no one-size-fits-all approach to modeling carbon fluxes released by soil respiration in coastal TAIs, and our study highlights the importance of further research and monitoring practices to improve our understanding of carbon dynamics and promote the sustainable management of coastal TAIs.

Different Approaches of Forest Type Classifications for Argentina Based on Functional Forests and Canopy Cover Composition by Tree Species

Modern forestry systems rely on typologies of forest types (FTs). In Argentina, several proposals have been developed, but they lack unified criteria. The objective was to compare different approaches, specifically focusing on (i) phenoclusters (functional forests based on vegetation phenology variations and climate variables) and (ii) forest canopy cover composition by tree species. We conducted comparative uni-variate analyses using data from national forest inventories, forest models (biodiversity, carbon, structure), and regional climate. We assessed the performance of phenoclusters in differentiating the variability of native forests (proxy: forest structure), biodiversity (proxy: indicator species), and environmental factors (proxies: soil carbon stock, elevation, climate). Additionally, we proposed a simple FT classification methodology based on species composition, considering the basal area of tree species. Finally, we compared the performance of both proposals. Our findings showed that classifications based on forest canopy cover composition are feasible to implement in regions dominated by mono-specific forests. However, phenoclusters allowed for the increased complexity of categories at the landscape level. Conversely, in regions where multi-specific stands prevailed, classifications based on forest canopy cover composition proved ineffective; however, phenoclusters facilitated a reduction in complexity at the landscape level. These results offer a pathway to harmonize national FT classifications by employing criteria and indicators to achieve sustainable forest management and conservation initiatives.

Triangular Greenness Index Analysis for Monitoring Fungal Disease in Pine Trees: A UAV-based Approach

The Triangular Greenness Index (TGI) is a vegetation index derived from high-resolution aerial images acquired using unmanned aerial vehicles (UAVs). It serves as a valuable tool for quantifying vegetation health and dynamics in the visible spectrum. The TGI combines key components, including red reflectance and green reflectance, extracted from UAV-based imagery. The red component represents chlorophyll absorption and photosynthetic activity, while the green component reflects vegetation density and canopy structure. By integrating these components, the TGI offers a comprehensive measure of photosynthetically active vegetation, utilizing UAVs as a data collection platform. This study highlight the importance of the TGI derived from UAV-based imagery in monitoring vegetation changes, assessing ecosystem responses, and tracking variations in land cover and biodiversity. Furthermore, the application of TGI analysis using UAV-based aerial imagery shows promise in accurately identifying and monitoring vegetation affected by fungal diseases. This integrated approach enables the detection of diseased trees based on distinct changes in greenness observed in their foliage. Because fungal diseases dry the plant and cause the green areas to disappear. The integration of UAV technology enhances the accuracy and efficiency of TGI calculation, contributing to effective management and conservation strategies in the context of fungal disease detection in vegetation. In this study, TGI was produced using UAV-based orthophoto and healthy and sick trees were determined. According to the accuracy analysis, producer accuracy for detecting green plants was 99.7% and user accuracy was 98.5%. Fungal disease could be detected with 98.5% producer accuracy and 96.5% user accuracy. The overall accuracy of the study was calculated as 98.6%.

Impacts of spatio-temporal change of landscape patterns on habitat quality across Zayanderud Dam watershed in central Iran

The biodiversity of an ecosystem is greatly influenced by the spatio-temporal pattern of the landscape. Understanding how landscape type affects habitat quality (HQ) is important for maintaining environmental and ecological sustainability, preserving biodiversity, and guaranteeing ecological health. This research examined the relationship between the HQ and landscape pattern. The study presented an interpretation of the biodiversity variation associated with the landscape pattern in the Zayanderud Dam watershed area by integrating the Land Change Modeler and the InVEST model. Landsat images and maximum likelihood classification were used to analyze the spatio-temporal characteristics of the landscape pattern in 1991 and 2021. The future landscape pattern in 2051 was simulated using a Land Change Modeler. Subsequently, the InVEST model and the landscape maps were used to identify the spatial distribution of HQ and its changes over three periods. The mean values of the HQ in the study area were 0.601, 0.489, and 0.391, respectively, demonstrating a decreasing trend. The effect of landscape pattern change on HQ was also assessed based on landscape metrics, including PD, NP, SHDI, and CONTAG. HQ had a significant positive correlation with the CONTAG parameter (R = 0.78). Additionally, it had a significant inverse correlation with NP (R = − 0.83), PD (R = − 0.61), and SHDI (R = − 0.42). The results showed that the habitats in the northern region had lower quality compared to those in the southern parts of the Zayanderud Dam watershed. The density, diversity, and connectivity of landscape patches significantly influence the HQ in the study area. This research has the potential to enhance understanding of the impacts of land change patterns on biodiversity and establish a scientific basis for the conservation of natural habitats. Additionally, it can facilitate efficient decision-making and planning related to biodiversity conservation and landscape management.

Spatiotemporal variation of microeukaryotic biodiversity and biotic condition associated with disinfectants after the COVID-19 lockdown in Wuhan, China

Intensive application of chlorine-based disinfectants driven by the COVID-19 pandemic was suspected to be detrimental to receiving water ecosystems, but with little field evidence. We characterized the occurrences of typical disinfectants and microeukaryotic communities in surface waters associated with three wastewater treatment plants (WWTP)-river systems one year after the lockdown in Wuhan, China. Trihalomethanes (THMs) declined from summer 2020 (0.01–1.82 ​μg/L) to summer 2021 (0.01–0.95 ​μg/L), whereas quaternary ammonium salts (QAs) increased from summer 2020 (0.53–6.35 ​ng/L) to summer 2021 (8.49–191 ​ng/L). Biodiversity monitoring with environmental DNA (eDNA) revealed significant temporal variation in microeukaryotic community composition. The monitored disinfectants were correlated with some eukaryotic communities as demonstrated by redundancy analysis. For example, QAs were positively related to Cryptophyta relative abundance, but negatively related to Rotifera relative abundance. A microeukaryote-based multimetric index indicated ecological impairment near the Han River WWTP outlet in 2020. Our findings indicate the influence of heavily used disinfectants on river microeukaryotic communities, and the usefulness of assessing mid-term ecological risks from disinfectants in the post COVID-19 era.

Diversity and growth patterns of woody species in the Mediterranean Coastal range of Chile: A case study in Altos de Cantillana

Background: The Altos de Cantillana mountain range (ACMR) in central Chile is composed of different vegetation communities, and is currently a priority site for conservation, due to its high endemism, high anthropogenic pressure and vulnerability to climate change. Research on biodiversity and carbon stocks in ACMR is essential to comprehend the resilience of these forests and to define conservation strategies. This study examines the spatial variability of biodiversity and tree biomass patterns along the entire altitudinal gradient of the ACMR. Methods: Six tree species communities were studied in Altos de Cantillana Nature Sanctuary, along an altitudinal gradient ranging from 415 to 2010 m. Woody species regeneration and inventory plots, as well as dendrochronological sampling in ~150 trees were carried out. Diversity patterns were analyzed using the Jaccard index and alpha index. Growth patterns of dominant trees species were analyzed by ring-width and trunk biomass chronologies, focusing on the recent megadrought period since 2010. Results: The forest inventory revealed a notable decline in alfa diversity patterns with increasing elevation. The moist sclerophyllous forest exhibited the highest diversity. However, we did not find a pattern between elevation and diversity (and abundance) at the seed regeneration inventory level. Additionally, we identified three clusters of woody species similarity: (i) sclerophyllous, shrubs and hygrophilous forest (&lt;1,000 m.a.s.l.); (ii) high-elevation sclerophyllous forest (&gt;1,500 m.a.s.l); and (iii) deciduous forests (~ 2,000 m.a.s.l). Furthermore, declining growth rates were observed in all communities studied beginning in the 1980s, with even a stronger reduction in radial growth (35% on average) and biomass accumulation (56% on average) when comparing the megadrought with six decades earlier. Conclusions: We concluded that there is a negative correlation between woody species diversity and elevation. However, there are no altitudinal patterns in seedling regeneration diversity and abundance, which puts the natural succession in ACMR at risk. Additionally, we have determined that the accumulation of trunk biomass in dominant woody species has been significantly impacted by the recent megadrought period. This has affected the sink capacity of forest communities in ACMR. Therefore, our findings can significantly contribute to more efficient and timely decision-making processes regarding the conservation and restoration of this globally unique ecosystem.

The role of slope as an environmental variable in plant biodiversity change in Aegean rangelands by SHE analysis: The case of Çakmar rangeland

Rangelands, which have rich plant and animal biodiversity, are also very important as a source of roughage for livestock. Rangeland vegetation patterns vary considerably under the influence of environmental factors. Indicator factors need to be identified and analyzed in order to manage conservation and utilization objectives. In rangelands of the Aegean region, the slope factor can greatly affect the rangeland plant biodiversity in areas close to the base rangeland. In order to investigate the spatial distribution and species variation in plant biodiversity caused by slope, 6 rangeland sections with different slopes were sampled in Koçarlı region (Aydın / Türkiye). Sampling was carried out using the transect method in the spring 2017 based on field observations. Following sampling, indicator species and species distribution and abundance were determined. Alpha biodiversity indices were used to determine the change in species biodiversity by SHE analysis. SHE analysis tests the relationship between S (species richness), H (Shannon-Wiener diversity index) and E (equality). This method aims to examine the contribution of the number of species and the concept of equity in the context of diversity. According to the information obtained as a result of the analysis, it was seen that the increase in slope may cause a decrease in species biodiversity. More species diversity was found in rangelands with low base and slope. Factors such as erosion and water transport affect the canopy and species abundance in high slope rangelands. However, other factors such as grazing intensity can reverse this situation. For this purpose, it has been determined that slope is an important environmental variable when preparing management plans based on grazing capacity and grazing animal species in vegetation studies.

Deep biogeographic barriers explain divergent global vertebrate communities

Biogeographic history can lead to variation in biodiversity across regions, but it remains unclear how the degree of biogeographic isolation among communities may lead to differences in biodiversity. Biogeographic analyses generally treat regions as discrete units, but species assemblages differ in how much biogeographic history they share, just as species differ in how much evolutionary history they share. Here, we use a continuous measure of biogeographic distance, phylobetadiversity, to analyze the influence of biogeographic isolation on the taxonomic and functional diversity of global mammal and bird assemblages. On average, biodiversity is better predicted by environment than by isolation, especially for birds. However, mammals in deeply isolated regions are strongly influenced by isolation; mammal assemblages in Australia and Madagascar, for example, are much less diverse than predicted by environment alone and contain unique combinations of functional traits compared to other regions. Neotropical bat assemblages are far more functionally diverse than Paleotropical assemblages, reflecting the different trajectories of bat communities that have developed in isolation over tens of millions of years. Our results elucidate how long-lasting biogeographic barriers can lead to divergent diversity patterns, against the backdrop of environmental determinism that predominantly structures diversity across most of the world.

Freshwater fish diversity from Siberut Island, a small island in the western part of Sumatra, Indonesia

Abstract. Roesma DI, Tjong DH, Aidil DR, Prawira FDL, Saputra A. 2024. Freshwater fish diversity from Siberut Island, a small island in the western part of Sumatra, Indonesia. Biodiversitas 25: 836-845. Indonesia is an archipelagic country with thousands of islands, including small islands with a variety of biodiversity, such as freshwater fish. Data and information on the fish biodiversity of small islands in the western part of Sumatra are limited, including Siberut Island. A study on freshwater fish diversity in Siberut Island was carried out using morphological and molecular methods. The study was conducted on seven rivers in the North and South Siberut Districts, Siberut Island. The study obtained 676 individuals, including 34 species, 26 genera, 16 families, and 10 orders. Oxudecidae is the family with the largest species (8), and Rasbora jacobsoni has the highest number of individuals (341). Species richness ranged from 2 to 18 species per site and was highest in the Srilanggai River. Siberut Island has low-moderate freshwater fish diversity. As many as 90 DNA barcodes of individuals from 34 species have been submitted to the Barcode of Life Data System. Freshwater fish groups do not receive enough attention from local communities and the government because of the richness of marine fish on Siberut Island. Apart from functioning as evidence of species richness, the results of this study are also useful for local communities' education.

The Spatiotemporal Variation in Biodiversity and Its Response to Different Future Development Scenarios: A Case Study of Guilin as an Internationally Renowned Tourist Destination in China

The preservation of biodiversity is crucial for maintaining ecological balance and promoting the harmonious development of mankind and nature. To formulate a biodiversity conservation plan for Guilin in China and accurately evaluate the impact of conservation measures on regional biodiversity, this study combined the InVEST model (v 3.7.0), the GeoSOS-FLUS model (v 2.3), and the landscape pattern index, analyzing the spatiotemporal changes in biodiversity from 2000 to 2020 in Guilin and simulating biodiversity under different development scenarios in 2040. The results showed the following: (1) The biodiversity index in Guilin displayed a declining trend, with the average annual value decreasing from 0.875 in 2000 to 0.870 in 2020. The area experiencing a reduction in biodiversity was primarily concentrated around the city. (2) The biodiversity level of each district and county had a large spatiotemporal difference, with the overall distribution characteristics of “higher in the northwest, southwest, and east, and lower in the northeast, southeast and central”. (3) The biodiversity hotspots were identified as priority areas for conservation; woodland and wetland were effectively protected, and the expansion of construction land and arable land was limited under the ecological protection scenario compared with the natural development scenario. (4) The annual average value of the biodiversity index of Guilin could reach 0.872 in 2040 after the adoption of ecological conservation measures, which is 0.013 higher than the natural development scenario. The results of this study can provide guidance for the construction of a national sustainable development model city and land use planning in Guilin, as well as a scientific reference for the creation of biodiversity conservation policies.