Variation In Biodiversity Research Articles

Biodiversity spatial distribution of benthic macroinvertebrate assemblages is influenced by anthropogenic disturbances at multiple spatial extents.

Understanding the patterns and mechanisms of biodiversity and its organization in space is essential for developing effective conservation strategies. Zeta diversity is an index of how taxa are shared by several sites, providing information on how ecological filters, including anthropogenic disturbances, influence biodiversity distribution. This study documents how anthropogenic disturbances at multiple spatial extents affect the spatial variation of benthic macroinvertebrate assemblages in lotic ecosystems. To test the relation between zeta diversity and anthropogenic disturbances, we used three disturbance metrics. (a) For in-stream disturbances, we used the percentage of fine sediment in the substrate (PCT_FN). (b) For local/riparian disturbances, we used the Local Disturbance Index (LDI). (c) For catchment disturbances we used the Catchment Disturbance Index (CDI). Our results showed that differing anthropogenic disturbances were differently important for spatial biodiversity variation in benthic macroinvertebrate assemblages. Relatively rarer taxa were usually more susceptible to in-stream and local/riparian-scale disturbances or local environmental filters. On the other hand, relatively common taxa were usually more related to catchment-scale disturbances or landscape resistance to dispersal. These results indicate that conservation efforts to maintain headwater ecosystem biodiversity must incorporate multiple spatial extents because relatively rare and relatively common taxa appear to be affected to different degrees by different anthropogenic disturbances at different spatial extents.

Biodiversity of Marine Mollusk Assemblages from Two Contrasted Algal Habitats in the Mediterranean Sea (Tossa de Mar, Costa Brava, NE Spain)

The malacological faunae of two algal habitats with different lighting conditions—a sciophilous wall and a photophilous one—both located in Tossa de Mar (Costa Brava, Girona, NE Spain), have been studied to examine the differences in the malacological communities, their distribution over time, and the role played by micromollusks in these algal habitats. Every two months, for a year, samples were collected via scuba diving and scraping standardized surfaces (20 × 20 cm) of the algal communities. In the laboratory, the samples were washed and filtered using two metal sieves (2 mm for coarse fraction and 513 µm for fine fraction). Mollusks were separated, identified, and later analyzed statistically to assess biodiversity indices and sample grouping. A total of 7913 mollusk specimens from 148 species (112 Gastropoda; 32 Bivalvia and 4 Polyplacophora) were identified across all samples, with 1669 specimens (84 species) from the sciophilous algae and 6244 specimens (133 species) from the photophilous algae. Moreover, 10 species accounted for 76.27% of the total abundance, with each species represented by over 100 specimens in the total samples. The gastropod Bittium latreillii was the most abundant species, with 2106 specimens recorded. Regarding the two fractions, 337 specimens (69 species) were found in the coarse fraction, while 7576 specimens (111 species) were found in the fine fraction. Significant differences were obtained between samples with respect to time, habitat type, and size fraction. The Shannon–Wiener biodiversity index values indicated differences between the two communities over time, as well as variations in biodiversity, with the photophilous community exhibiting higher values. It was demonstrated that algal thalli provide a highly suitable substrate for juvenile forms and micromollusks. Our findings, combined with the literature and various online citations, establish Tossa de Mar as the town on the Catalan coast with the best-documented malacological fauna.

Impact of Babaco (Vasoncelea x pentagona (Heilborn) Mabb.) Fruit Ripening Stages on Phytochemical Composition and Biological Properties.

Background: This research article delves into Babaco fruit's-an Ecuadorian product with immense nutraceutical potential phytochemical composition and biological activity-in different maturation fruit stages. Bridging the gap between food and medicine, nutraceuticals offer health benefits beyond basic nutrition. Methods: Specifically, this study investigates Babaco's antioxidant and its phenolic and flavonoid content across different ripening stages: physiological maturity, organoleptic quality immaturity, and commercial maturity. Results: This last stage of maturity exhibits the highest antioxidant activity, making it the optimal phase for marketing Babaco as a nutraceutical product. Further LC-MS analysis reveals the specific secondary metabolites responsible for this potent antioxidant capacity. Conclusions: By introducing Babaco as a nutraceutical fruit, Ecuador can showcase its unique phytochemical profile, which is rich in phenolic compounds and flavonoids. Consumers stand to gain from Babaco's antioxidant properties, supporting overall health and well-being. Recognizing Babaco's antioxidant potential aligns perfectly with Ecuador's diverse biodiversity and offers a promising avenue for health-conscious choices.

Soil and Sediment Organisms as Bioindicators of Pollution

This review examines the role of soil and sediment organisms as bioindicators in environmental pollution assessment. As fundamental elements of terrestrial ecosystems, soils harbour a rich and diverse biodiversity that plays a key role in regulating ecological processes. The use of bioindicators provides a sensitive and specific approach to detecting the effects of chemical, biological, and physical pollutants on soil health. The review presents a detailed analysis of the types of contaminants commonly encountered, the soil organisms used as bioindicators, and the criteria for selecting the most appropriate bioindicators. It also discusses assessment methods, including soil sampling and analysis techniques, and the biological and ecological indices used to measure contamination. Regional case studies illustrate the practical application of bioindicators for assessing soil quality in different geographical contexts. The review also highlights current challenges to the use of bioindicators, such as technical limitations and the variability of organism responses, and suggests perspectives for future research, including technological innovation and the integration of bioindicators into environmental policy.

Multitrophic assembly influences β‐diversity across a tripartite system of flowering plants, bees, and bee‐gut microbiomes

Theoretical frameworks of terrestrial community assembly often focus on single trophic levels (e.g. plants) without considering how complex interdependencies across different trophic levels influence assembly mechanisms. Yet, when multiple trophic levels are considered (e.g. plant–pollinator, plant–microbe interactions) the focus is typically on network analyses at local spatial scales. As spatial variation in biodiversity (β‐diversity) is increasingly being recognized for its relevance in understanding community assembly and conservation, considering how β‐diversity at one trophic level may be influenced by assembly processes that alter abundance and composition of interacting communities at a different trophic level (multitrophic dependency) is critical. Here, we build on single trophic level community assembly frameworks to explore the assembly processes affecting β‐diversity in multitrophic communities comprising flowering plants, their bee pollinators, and the corresponding bee‐gut microbiota to better understand the importance of multitrophic dependency in community assembly. Using distance‐based redundancy analysis and variation partitioning, we investigated community assembly processes across three interconnected trophic levels in two ecological regions in southern California: the Santa Monica Mountains and three islands of the Channel Island Archipelago. We found that the deterministic effects of multitrophic dependency are stronger on directly connected trophic levels than on indirectly connected trophic levels (i.e. flowers explain bee communities and bees explain bee‐gut bacteria communities, but flowers weakly explain variation in bee‐gut bacteria communities). We also found notable regional variation, where multitrophic dependency was weaker on the Channel Islands as ecological drift was more pronounced. Our results suggest that integrating the influence of multitrophic dependency on community assembly is important for elucidating drivers of β‐diversity and that multitrophic dependency can be determined by the regional context in which β‐diversity is measured. Taken together, our results highlight the importance of considering multiscale perspectives – both multitrophic and multiregional – in community assembly to fully elucidate assembly processes.

Variation in biodiversity and abundance of functional groups of arthropods along a tropical elevational gradient in Puerto Rico

AbstractElevational gradients represent platforms for exploring the effects of environmental variation on biodiversity. The environmental correlates of these spatial gradients are likely to be modified during the Anthropocene, as species respond to global change drivers including warming and increased frequency of extreme events. We quantified variation in the abundance of four functional groups of canopy arthropods (i.e., folivores, sap‐suckers, detritivores, and predators), as well as in aspects of biodiversity on each of six host‐plant species along two elevational transects in the Luquillo Mountains of Puerto Rico: a mixed forest transect, traversing tabonuco, palo colorado, and elfin forests, and a palm forest transect, comprising only patches dominated by sierra palm (Prestoea acuminata). We expected gradients in arthropod abundance and biodiversity to be host‐tree specific, and for gradients on palm to differ between transects due to a combination of mechanisms associated with host selection, rescue effects, habitat structure, and source pool dynamics. In general, abundance and biodiversity declined with elevation. The ways in which abundance declined with increasing elevation was contingent on host tree identity and on arthropod functional group, whereas all aspects of biodiversity declined with elevation in consistent manners regardless of host tree identity or transect. Similarly, turnover (beta components of biodiversity between sequential elevational strata) did not differ between transects. Decreases in productivity with increasing elevation may be responsible for gradients in abundance or biodiversity. However, host‐specific and functional group‐specific gradients suggest that elevational effects manifest differently depending on tree species identity and resource bases that are consumer specific.

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.

One to rule them all? Assessing the performance of sustainable forest management indicators against multitaxonomic data for biodiversity conservation

Several regional initiatives and reporting efforts assess the state of forest biodiversity through broad-scale indicators based on data from national forest inventories. Although valuable, these indicators are essentially indirect and evaluate habitat quantity and quality rather than biodiversity per se. Therefore, their link to biodiversity may be weak, which decreases their usefulness for decision-making.For several decades, Forest Europe indicators assessed the state of European forests, in particular their biodiversity. However, no extensive study has been conducted to date to assess their performance – i.e. the capacity of the indicators to reflect variations in biodiversity – against multitaxonomic data. We hypothesized that no single biodiversity indicator from Forest Europe can represent overall forest biodiversity, but that several indicators would reflect habitat quality for at least some taxa in a comprehensive way. We tested the set of Forest Europe's indicators against the species richness of six taxonomic and functional groups across several hundreds of sampling units over Europe. We showed that, while some indicators perform relatively well across groups (e.g. deadwood volume), no single indicator represented all biodiversity at once, and that a combination of several indicators performed better.Forest Europe indicators were chosen for their availability and ease of understanding for most people. However, we showed that gaps in the monitoring framework persist, and that surveying certain taxa along with stand structure is necessary to support policymaking and tackle forest biodiversity loss at the large scale. Adding context (e.g. forest type) may also contribute to increase the performance of biodiversity indicators.

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%.