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In the socio-ecological landscapes of tropical mountains, including the highly diverse Eastern Himalaya, fragments of natural forests have been traditionally managed as part of different agriculture systems. Recent studies have recognized their role as important biodiversity repositories outside protected areas. However, basic information on forest structure and composition of these forests outside protected areas is still limited in the Himalaya. In the current study, diversity, structure, composition, and regeneration status of non-protected forests were studied across 15 spatially different sites in the socio-ecological landscapes of Darjeeling-Sikkim, Eastern Himalaya, across an approximate elevation range of 500-2300 m above sea level. Quadrats (20 m × 5 m) were used to enumerate woody species in the study area. Enumeration of 156 quadrats (= 1.56 ha) resulted in a total of 249 woody species, of which species such as Schima wallichii, Alnus nepalensis, and Engelhardtia spicata were found to dominate the existing stand of trees. The vegetation structure of these forests was found to be almost comparable with that of protected forests, as assessed by prior studies in the same landscape. Species composition of woody plants in the study area were found to be primarily influenced by elevation. Assessment of regeneration patterns found the forests to have a high regeneration potential, however, the most dominant tree species of the area had relatively fewer saplings, indicating probable replacement of localized species of large trees by disturbance-adapted species. The current study adds to the literature on the structure and composition of non-protected forests in the tropical mountains. [ABSTRACT FROM AUTHOR]

Farmland habitats witness steep declines in biodiversity. One rapidly declining farmland species is the ortolan bunting Emberiza hortulana. In Finland, a staggering 99% of the population has been lost during the past 30 years. Changes in the breeding habitats have been proposed as a reason for the decline, although hazards during migration and wintering may also play a role. We gathered a 19‐year data set of Finnish ortolan buntings and studied which spatial characteristics, habitat features, and climate factors might explain the population growth rate at the singing‐group level. As explanatory variables we used region, density of small‐scale structures, proportion of agricultural area in the landscape, diversity of crop types, proportion of bare ground, and temperature and precipitation of previous breeding season. Higher population growth rates were associated with higher crop type diversity and higher proportion of bare ground. The mosaic of various crop plants and bare ground may provide a wider array of feeding, hiding and nesting places, and an easier access to food. Higher growth rates were also associated with landscapes dominated by interconnected agricultural land, which may reflect the species' sociability and avoidance of forested areas. The North Ostrobothnia region had higher growth rates compared to other regions. We suggest that northern populations of ortolan bunting should be targeted for further studies on feeding and breeding ecology as well as for urgent conservation actions, such as increasing crop type diversity and bare ground. [ABSTRACT FROM AUTHOR]

The Matsu Islands Tern Refuge comprises eight reefs located at a relay station on the East Asian bird migration route, and it attracts many transiting, wintering, or breeding birds to inhabit and live on the reefs every year. In order to understand the compositions of plant communities as a breeding habitat for seabirds, we investigated the plant communities of the eight reefs. A total of 130 plots of 10 × 10 square meters were established, from which we found 107 species of plants in 102 genera and 51 families. Among this, we found one critically endangered (CR) species, four vulnerable (VU) species, and three near-threatened (NT) species. The result of two-way indicator species analysis (TWINSPAN) and indicator value (IndVal) showed 130 samples were divided into 11 vegetation types; most of the vegetation types had significant indicator species. We also use the two-way to present the plot of detrended correspondence analysis (DCA) by vegetation types and reefs. Moreover, this result reveals that these samples were more clearly cluster divided by islands. Our results reveal that the compositions and characteristics of plant communities were related clearly to the environmental factors for each reef in the Matsu Islands Tern Refuge. Canonical correspondence analysis (CCA) indicated that species composition of vegetation yielded high correlation with soil property, especially with soil pH. In addition, we found that the traces of bird activity is relevant to the characteristics and structures of plant communities. We found that the plant communities comprising low-grass shrubs would provide relatively soft nesting materials and sheltering effects for eggs or hatchlings for terns. Compared to low-grass shrubs, the traits of high-grass shrubs would not be beneficial to nest for breeding of terns on the ground, and no nested trace was found in these plant communities. [ABSTRACT FROM AUTHOR]

Remotely sensed measures of vegetation structure have been shown to explain patterns in the occurrence and diversity of several animal taxa, including birds, mammals, and invertebrates. However, very little research in this area has focused on reptiles and amphibians (herpetofauna). Moreover, most remote sensing studies on animal–habitat associations have relied on airborne or satellite data that provide coverage over relatively large areas but may not have the resolution or viewing angle necessary to measure vegetation features at scales that are meaningful to herpetofauna. Here, we combined terrestrial laser scanning (TLS), unmanned aerial vehicle laser scanning (ULS), and fused (FLS) data to provide the first test of whether vegetation structural attributes can help explain variation in herpetofauna abundance, species richness, and diversity across a woodland landscape. We identified relationships between the abundance and diversity of herpetofauna and several vegetation metrics, including canopy height, skewedness, vertical complexity, volume of vegetation, and coarse woody debris. These relationships varied across species, groups, and sensors. ULS models tended to perform as well or better than TLS or FLS models based on the methods we used in this study. In open woodland landscapes, ULS data may have some benefits over TLS data for modeling relationships between herpetofauna and vegetation structure, which we discuss. However, for some species, only TLS data identified significant predictor variables among the LiDAR‐derived structural metrics. While the overall predictive power of models was relatively low (i.e., at most R2 = 0.32 for ULS overall abundance and R2 = 0.32 for abundance at the individual species level [three‐toed skink (Chalcides striatus)]), the ability to identify relationships between specific LiDAR structural metrics and the abundance and diversity of herpetofauna could be useful for understanding their habitat associations and managing reptile and amphibian populations. [ABSTRACT FROM AUTHOR]

The distribution and composition of the vegetation are greatly affected by the edaphology and topography of an area. The current study explores the vegetation structure of the herbaceous layer at various habitats of district Kohat for the first time. A survey was conducted during the spring seasons of 2021, 2022 and 2023 selecting 40 sites on the basis of edaphology, topography, altitude, aspect and status. Data was collected via quadrat approach to establish plant communities by species Importance Value (IV), point out dominant species by Total IV (TIV) and dominant families via Total Family IV (TFIV). The quantitative biological spectrum was also calculated. Communities' phytosociological characteristics were analyzed via various diversity indices (Shannon's Index (H), Simpson's Index (D), Species Richness (SR), Evenness (E) and Maturity index (Mi)) while similarity between the communities was calculated by using Sorensen's Index. The findings revealed a total of 253 species belonging to 57 families having the dominant species Cynodon dactylon (L.) Pers. (TIV, 484.3) followed by Saussuria heteromalla (D. Don) Hand. (TIV, 360.4), Anagallis arvensis L. (TIV, 353.2) and Aristida adscensionis L. (TIV, 349.65). Among 40 plant communities, Poaceae (TFIV, 2706.6), Asteraceae (TFIV, 2018.8), Fabaceae (TFIV, 1071.5) and Brassicaceae (TFIV, 825.9) were the dominant families. Therophytes (TIV, 7882) class was the dominant life form class followed by hemicryptophytes (TIV, 2517) while microphylls (TIV, 4669) class was the dominant leaf size class followed by nanophylls (TIV, 5469). Environmental factors i.e. topography and edaphic characteristics, showed significant effects on the diversity of the communities. The study concludes in a diverse pattern of distribution with a rich flora in the area warranting its documentation which will preserve the valuable species opening vistas for future research. [ABSTRACT FROM AUTHOR]

Vegetation vertical complexity influences biodiversity and ecosystem productivity. Rapid warming in the boreal region is altering patterns of vertical complexity. LiDAR sensors offer novel structural metrics for quantifying these changes, but their spatiotemporal limitations and their need for ecological context complicate their application and interpretation. Satellite variables can estimate LiDAR metrics, but retrievals of vegetation structure using optical reflectance can lack interpretability and accuracy. We compare vertical complexity from the airborne LiDAR Land Vegetation and Ice Sensor (LVIS) in boreal Canada and Alaska to plant functional type, optical, and phenological variables. We show that spring onset and green season length from satellite phenology algorithms are more strongly correlated with vegetation vertical complexity (R = 0.43–0.63) than optical reflectance (R = 0.03–0.43). Median annual temperature explained patterns of vegetation vertical complexity (R = 0.45), but only when paired with plant functional type data. Random forest models effectively learned patterns of vegetation vertical complexity using plant functional type and phenological variables, but the validation performance depended on the validation methodology (R2 = 0.50–0.80). In correlating satellite phenology, plant functional type, and vegetation vertical complexity, we propose new methods of retrieving vertical complexity with satellite data. [ABSTRACT FROM AUTHOR]

Hurricanes are extreme climatic events frequently affecting tropical regions such as the tropical dry forests (TDFs) in Mexico, where its frequency/intensity is expected to increase toward the year 2100. To answer how resistant is a Mexican tropical dry forest to a high-intensity hurricane, and if its degree of resistance was mediated by its conservation degree, we evaluated the effect of a category 4 hurricane over the tree community, soil nutrients, and soil enzymatic activity in two contrasting TDF ecosystems: Old-Growth Forest (OGF) and Secondary Forest (SF). In general, vegetation richness and diversity showed very high resistance one year after the hurricane, but several structural attributes did not, especially in the OGF where the tree mortality related to vegetation structure and spatial distribution of individuals was higher. Then, in the short term, SF vegetation appeared to be more resistant, whereas the OGF, with more biomass to lose, appeared to be more vulnerable. Conversely, most soil attributes showed low resistance in both stages, but especially in SF which could face more severe nutrient limitations. The response of TDF to high-intensity hurricanes, in terms of above- and belowground processes, was in part dependent on its disturbance level. Moreover, an increase in the intensity/frequency of hurricanes could lead this TDF toward a high nutrient limitation (especially by phosphorus) for the plants and consequently toward a loss of soil functioning, especially in the SF. This eventually could produce a severe degradation in fundamental attributes and functions of the ecosystem. [ABSTRACT FROM AUTHOR]

Saproxylic insects are an important component of forest biodiversity; however, their ecological requirements are mostly studied on beetles, while other groups are less considered. Aculeate Hymenoptera provide valuable ecosystem services, and some rely on deadwood cavities. We studied cavity-nesting aculeate Hymenoptera using wooden trap-nests set in a heterogeneous partially rewilded woodland area in Central Bohemia, Czech Republic, and tested their nesting preferences in association with canopy openness, amount of deadwood, and the diversity of surrounding vegetation types. We used 100 trap-nests in five microbiotopes—forest edge, shady closed-canopy forest, open patches in closed-canopy forest, open-grown trees in wooded pasture, and shady groves in wooded pasture, over 2 years. We reared 824 specimens belonging to 26 species of saproxylic hymenopterans. We found no effect of microbiotope on total species richness and richness of nest parasites, but richness of nest builders was highest in forest edge and lowest in open-grown trees in wooded pasture. Species composition of hymenopterans was driven by a wider habitat context: despite the proximity of the habitats, the forest, especially closed-canopy patches, hosted a different community, dominated by wasps, than open wooded pasture. Moreover, open patches in forest differed in composition from the closed-canopy patches, suggesting that in production forests, the diversity of saproxylic hymenopterans may be limited by the overall low share of open canopy stages. Deadwood (amount and diversity) did not affect the saproxylic bees and wasps in any way. Implications for insect conservation: Our results support conservation measures leading to diversification of the forest canopy and vegetation structure in order to support rich communities of saproxylic Hymenoptera, especially in protected areas. [ABSTRACT FROM AUTHOR]

Diaspore dispersal is crucial in shaping plant population dynamics, biodiversity, and ecosystem functions. The effect of the vegetation structure on the secondary wind dispersal of diaspores with different appendage types is not well understood. Using a wind tunnel and a high-definition video camera, we accurately measured the lift-off and dispersal velocities of diaspores from sixteen plant species across six wind velocities (2, 4, 6, 8, 10, and 12 m s−1) under six simulated vegetation structures. Vegetation structure and appendage type were pivotal factors, explaining 41.1% and 42.3% of the variance in lift-off velocity and accounting for 12.0% and 25.3% of the variability in diaspore dispersal velocity, respectively. Vegetation coverage was the main factor influencing near-surface wind velocity, and the lift-off and dispersal velocities of diaspores changed significantly when vegetation coverage exceeded 40%. Diaspores with one wing, having high lift-off velocities and low dispersal velocities, adopt the anti-long-distance wind dispersal strategy, whereas diaspores with pappus, having low lift-off velocities and high dispersal velocities, adopt the long-distance wind dispersal strategy. In contrast, diaspores with thorn, discoid, balloon, and four wings adopt the non-long-distance wind dispersal strategy, suitable for environments such as low-coverage deserts and desert steppes but not high-coverage typical steppes. This study could help comprehend the effect of the vegetation structure on the dispersal process of diaspores, which facilitate habitat restoration and biodiversity conservation of grassland and forest ecosystems. [ABSTRACT FROM AUTHOR]

Temperate insectivorous bats value high prey abundance and appropriate vegetative structure when selecting foraging habitats. Forests, particularly in the eastern United States, provide prime foraging habitats for bats but can be heavily impacted by non-native plants, which may alter arthropod diversity and abundance, as well as vegetative structure. To investigate the associations between non-native plants and insect abundance, vegetative structure, and, consequently, bat activity, we performed vegetation surveys, insect trapping, and acoustic monitoring at 23 forested plots in northern New Jersey, USA. We predicted that non-native vegetation would either positively influence bat activity by increasing structural openness (thus, facilitating flight) or negatively influence bat activity by lowering the abundance of putative prey. We also hypothesized that vegetative characteristics, and therefore non-native vegetation, impact bats differently depending on their foraging habitat preferences. The percent of non-native cover of the ground and midstory vegetative layers of our study plots ranged from 0 to 92.92% ( x ¯ = 46.94 ± 5.77 SE) and was significantly correlated with structural vegetative characteristics, such as midstory clutter (β = 0.01 ± 0.006 SE), but not putative prey abundance (β = −0.81 ± 2.57 SE). Generalized linear models with only vegetative characteristics best predicted overall bat activity and foraging, which were greatest in areas with a high percent non-native vegetation and low midstory clutter. Although percent non-native vegetation and midstory clutter were also significant effects for bats that prefer to forage in open areas, neither vegetative characteristics nor prey abundance were significant effects for clutter-loving bats. Such findings suggest that vegetative structure is more important than prey availability for predicting overall insectivorous bat activity, but other factors, such as foraging strategy and life history traits, can impact how bat guilds respond to non-native vegetation. Therefore, more research is required to reveal additional mechanisms by which non-native plants impact bats. [ABSTRACT FROM AUTHOR]

Context: Alpine ecosystems are threatened by warming and an associated increase in fire frequency. There is a gap in our knowledge of succession in Tasmanian alpine heath more than 50 years after fire. The literature suggests that the alpine successional progression usually involves decreasing rates of change, decreasing differences among fire ages, ongoing transitions among shrub species, ongoing transitions from some lifeforms/species to others, and that warming results in increases in species richness. Aims: We test for these tendencies up to 75 years from fire in alpine vegetation on kunanyi/Mount Wellington, Tasmania, Australia. Methods: We documented the changes in vegetation structure and composition between 1998 and 2022 in plots on either side of an alpine fire boundary in the alpine heathland and used earlier data and observations to extend the record of change after fire to 75 years. We put these changes in the context of the only area of alpine vegetation that was not burnt in 1947 or later. Key results: The area last burnt in 1947 exhibited declines in all lifeform covers between 1998 and 2022. All lifeforms except tall shrubs and mat shrubs declined in cover in the area last burnt in 1962. By 2022, shrub cover in the 1962-burnt area had not attained equivalence with the area last burnt in 1947. Herbs had the most dramatic decline in both fire-age classes. There were few shrub seedlings in 2022. All but six taxa, three being exotic, were observed in both the plots and previous broader surveys. Increases in species richness caused by the upward migration of lower-elevation species were not observed. The long-unburnt patch lacked the major dominant of the 1947-burnt plots, namely Orites acicularis , and was dominated by a gymnosperm absent from most of the mountain. Conclusions: Succession follows the initial floristic composition model. The differences in trajectories from the 1947 and 1962 fires could possibly be due to desiccation or abrasion damage from increasing wind speeds and temperatures. There are strong indications of further potential change in the absence of fire. Implications: The slow rate of recovery and its on-going nature emphasise the importance of keeping fire out of this vegetation type. We compared vegetation in alpine heath plots that regenerated after fires of 1947 and 1962. Herbs and graminoids plummeted in cover and species richness between 1998 and 2022, whereas shrubs continued to increase in cover in the 1962-burnt, but decreased in the 1947-burnt area. Shrubs exhibited compositional change up to 75 years after fire. A failure of the shrub layer to be more similar between the fire years might be due to stronger winds and higher temperatures. A predicted climate change-induced increase in diversity did not occur. Image by Jamie Kirkpatrick. [ABSTRACT FROM AUTHOR]

According to the Sonotope Hypothesis, the heterogenous nature of the acoustically sensed, but not yet interpreted, environmental sounds (i.e., sonoscape) is created by the spatial and temporal conformation of sonic patches (sonotopes) as recently been described in a Mediterranean rural landscape. We investigated the Sonotope Hypothesis in a mountain beech forest of the Northern Apennines, Italy that is notoriously poor in soniferous species. Our aim was to test whether sonotopes were temporally distinct over seasonal and astronomical timeframes and spatially configured in relation to vegetation variables. We used the Acoustic Complexity Index (ACItf) to analyze the heterogeneity of sonic information gathered from an array of 11 sound recorders deployed within a lattice of eleven 4-ha hexagonal sample sites distributed throughout a 48-ha managed beech forest. We visualized and described the temporal patterns of ACItf between seasons (May-June and July-August 2021), across six astronomical periods (Night I, Morning Twilight, Morning, Afternoon, Evening Twilight, and Night II), and according to two aggregated frequency classes (<2000 and >2000 Hz). We introduced Spectral Sonic Signature (SSS) calculated from the sequence of ACItf values along frequency bins as a descriptor of the dynamic production of sounds across spatial and temporal scales. We calculated Mean Spectral Dissimilarity to compare SSS values across temporal periods and between sample sites. We identified sonotopes by grouping similar SSS for each sample site generated from cluster analyses and visualized their spatial arrangements. Frequencies <2000 Hz (mainly geophonies from wind and rain) were more prevalent than frequencies >2000 Hz (mainly biophonies from songbirds). Despite there being no strong relationship to vegetation variables and minimal biophony and anthropophony, distinct sonotopes still emerged for every astronomical and seasonal period. This suggests that the sonoscape expresses distinct spatial and temporal sonotope configurations associated with the temporal and spatial patterns of geophysical events that generate geophonies with minimal animal or anthropogenic occurrences. A new strategy based on the reintroduction of indigenous trees and shrubs in managed clearings should be considered for enhancing local biodiversity conservation along with ecoacoustic monitoring based on the Sonotope Hypothesis. [ABSTRACT FROM AUTHOR]

Aim: There is widespread support that species richness increases with the available energy of an ecosystem, but the mechanisms underlying this driver of biodiversity patterns remain elusive. We evaluated gradients of functional diversity to test whether the higher species richness of productive, structurally diverse environments is due to a greater range of niches being supported by the abiotic conditions present (environmental filtering), greater availability of biotic resource and habitat niches (more niches) or increasing functional similarity of species (niche packing). Location: Australia. Taxon: Birds and mammals. Methods: We used structural equation modelling to evaluate the relative contributions of climatic harshness (actual evapotranspiration, AET) and the availability of resource (gross primary productivity, GPP) and habitat (tree height) niches on taxonomic richness and functional richness, dispersion and evenness. We performed parallel analyses within 15 bioclimatic zones and continentally to evaluate the scaling of biodiversity gradients and the shifting balance between niche‐based mechanisms along environmental gradients. Results: All continental diversity gradients were primarily associated with energy variables, but while species richness of both taxa and all functional diversity measures of bird assemblages increased with AET, mammal functional diversity was more strongly associated with GPP gradients. Results were more variable at the regional scale, but species richness gradients along tree height (birds and mammals) and GPP (mammals) within bioclimatic zones tended not to be paralleled by increases in functional richness or dispersion. Main Conclusions: The niche‐based explanations of biodiversity gradients varied in importance with scale, position on environmental gradients and taxonomic group. At the continental extent, bird biodiversity gradients were structured by environmental filtering by climatic harshness, while mammal biodiversity was related to the increasing availability of resource niches with increasing productivity. Niche packing was more prominent at the regional scale, especially in bioclimatic zones where productivity and vegetation height were less limiting, and in mammal assemblages, suggesting that biodiversity patterns scale differently for birds and mammals. [ABSTRACT FROM AUTHOR]

Context: Habitat loss and degradation are major drivers of biodiversity loss worldwide. In particular, wetland environments are being removed and degraded faster than any other terrestrial habitat on earth. The loss and degradation of wetlands has been particularly pronounced in south-eastern Australia. Aims: Here we investigated the impact of habitat loss and degradation on the Data Deficient glossy grass skink (Pseudemoia rawlinsoni), a species that predominantly favours wetland vegetation in south-eastern Australia. Methods: We established artificial cover-object (roofing tiles) survey grids in paired remnant and disturbed sites at six locations across Victoria, Australia, and surveyed for skinks between November 2021 and April 2022. Key results: Sites at which glossy grass skinks occur are characterised by tall dense vegetation, with a high cover of matted biomass. Thermal profiles within these complex vegetation structures remain much cooler during hot days, and warmer during cold nights, than external temperatures. Nearby disturbed sites (i.e. grazed or mowed areas within dispersal distance of remnant sites) are generally devoid of skinks, have very low and structurally simple (open) vegetation, and have thermal regimes that offer lizards no respite from high summer temperatures. We found that roofing tiles are an effective way to survey for glossy grass skinks; even on cool cloudy days, the temperature of tiles, and the lizards sheltering beneath them, are often much higher than ambient temperatures. Conclusions: These findings implicate habitat loss and degradation as having a substantial negative impact on glossy grass skink presence and abundance; skinks largely avoid disturbed areas, even at sites immediately adjacent to remnant habitat. This may be driven not simply by the removal of tall and dense vegetation structures, but the consequent loss of the optimal thermal buffer afforded by such structures. Implications: Our study emphasises the threat that habitat loss and degradation pose to wetland species in Australia, and throughout the world. Habitat loss and degradation are a major threat to the persistence of wildlife, especially for animals with specific habitat requirements. We performed population surveys on wild glossy grass skinks in southern Victoria (Australia), which revealed that this rare wetland lizard is sensitive to vegetation being disturbed by mowing or grazing. Our study highlighted the importance of protecting habitat-specialised wetland fauna in Australia and globally. Photographs by Jules Farquhar. [ABSTRACT FROM AUTHOR]

Vegetation classifications are a valuable tool for guiding management decisions. Vegetation can be classified at different levels of resolution for different purposes. Aggregating finer‐resolution classification units to simplify planning and decision‐making is becoming more common in land management. However, little is known about which resolution or scale of aggregation is appropriate for specific land management practices and the factors to consider when aggregating vegetation classification units. There is a risk that aggregated classification units may overlook vital floristic and structural differences between communities and not accurately represent the patterns of variation in vegetation. This may lead to unanticipated adverse outcomes from management actions. We compared three classification systems to test how well each represented patterns of variation in the vegetation of a semi‐arid region in Victoria, Australia: (a) a finer‐level classification system; (b) a coarser‐resolution system that aggregated finer compositional resolution units for fire management purposes; and (c) a coarser‐resolution classification based on Climate Zones. We conducted floristic and vegetation structure surveys at 249 sites stratified across a climate gradient. Sites were assigned to vegetation classifications based on mapped data layers and checked by ground truthing prior to inclusion. The classification based on a finer compositional resolution best represented variation in both the floristic and structural patterns of the vegetation across this region. This was not unexpected, because accuracy is traded‐off against simplicity when aggregating vegetation classification units. However, the aggregated classification also performed poorly in representing patterns of vegetation when compared with a simple scheme based on Climate Zones. Assessing the adequacy of aggregated vegetation classification units is important, yet often overlooked. To be effective, aggregated vegetation classes must reflect the underlying factors that drive patterns of variation in the vegetation to ensure they support intended management outcomes. [ABSTRACT FROM AUTHOR]

Light detection and ranging (lidar) has emerged as a valuable tool for examining the fine‐scale characteristics of vegetation. However, lidar is rarely used to examine coastal wetland vegetation or the habitat selection of small mammals. Extensive anthropogenic modification has threatened the endemic species in the estuarine wetlands of the California coast, such as the endangered salt marsh harvest mouse (Reithrodontomys raviventris; SMHM). A better understanding of SMHM habitat selection could help managers better protect this species. We assessed the ability of airborne topographic lidar imagery in measuring the vegetation structure of SMHM habitats in a coastal wetland with a narrow range of vegetation heights. We also aimed to better understand the role of vegetation structure in habitat selection at different spatial scales. Habitat selection was modeled from data compiled from 15 small mammal trapping grids collected in the highly urbanized San Francisco Estuary in California, USA. Analyses were conducted at three spatial scales: microhabitat (25 m2), mesohabitat (2025 m2), and macrohabitat (~10,000 m2). A suite of structural covariates was derived from raw lidar data to examine vegetation complexity. We found that adding structural covariates to conventional habitat selection variables significantly improved our models. At the microhabitat scale in managed wetlands, SMHM preferred areas with denser and shorter vegetation and selected for proximity to levees and taller vegetation in tidal wetlands. At the mesohabitat scale, SMHM were associated with a lower percentage of bare ground and with pickleweed (Salicornia pacifica) presence. All covariates were insignificant at the macrohabitat scale. Our results suggest that SMHM preferentially selected microhabitats with access to tidal refugia and mesohabitats with consistent food sources. Our findings showed that lidar can contribute to improving our understanding of habitat selection of wildlife in coastal wetlands and help to guide future conservation of an endangered species. [ABSTRACT FROM AUTHOR]

As a crucial component of terrestrial ecosystems, urban forests play a pivotal role in protecting urban biodiversity by providing suitable habitats for acoustic spaces. Previous studies note that vegetation structure is a key factor influencing bird sounds in urban forests; hence, adjusting the frequency composition may be a strategy for birds to avoid anthropogenic noise to mask their songs. However, it is unknown whether the response mechanisms of bird vocalizations to vegetation structure remain consistent despite being impacted by anthropogenic noise. It was hypothesized that anthropogenic noise in urban forests occupies the low-frequency space of bird songs, leading to a possible reshaping of the acoustic niches of forests, and the vegetation structure of urban forests is the critical factor that shapes the acoustic space for bird vocalization. Passive acoustic monitoring in various urban forests was used to monitor natural and anthropogenic noises, and sounds were classified into three acoustic scenes (bird sounds, human sounds, and bird-human sounds) to determine interconnections between bird sounds, anthropogenic noise, and vegetation structure. Anthropogenic noise altered the acoustic niche of urban forests by intruding into the low-frequency space used by birds, and vegetation structures related to volume (trunk volume and branch volume) and density (number of branches and leaf area index) significantly impact the diversity of bird sounds. Our findings indicate that the response to low and high frequency signals to vegetation structure is distinct. By clarifying this relationship, our results contribute to understanding of how vegetation structure influences bird sounds in urban forests impacted by anthropogenic noise. [ABSTRACT FROM AUTHOR]

As the mining operation is completed, the key lies in how to rehabilitate and restore the soil ecosystem. In this study, properties of soil samples from the same soil layer of the reclamation area for different vegetation types including Oriental arborvitae, Chinese holly, Chinese littleleaf box, and Wheat were tested. The results showed that different vegetation types possessed varying abilities to restore the ecosystem of soil in coal mining areas. In addition, the land for oriental arborvitae also showed higher soil enzyme activity, fungal abundance, and diversity index. The utilization of oriental arborvitae in coal mine reclamation projects could enhance soil quality, promote soil fertility, enrich microbial diversity, and expedite the establishment of a sustainable ecosystem in polluted soils. [ABSTRACT FROM AUTHOR]

How species interact with human‐disturbed environments is a central focus of conservation biology. Within disturbed landscapes, regenerating forests have potential to provide habitat for forest species, especially as increasing amounts of primary forest are lost. As secondary forest regenerates beside primary forest, it increases habitat heterogeneity. However, relatively little is known about the influence of habitat heterogeneity on space use. In this study, we analyzed the topography and vertical vegetation structure of regenerating forest, small forest fragments, and undisturbed rainforest in the central Amazon to determine (1) how these structural characteristics influence understory mixed‐species flock space use and (2) how the vegetative preferences of flocks varied across a disturbance gradient. We first used behavioral observations to quantify the vertical foraging niche of flocks and then associated variation in horizontal space use with the three‐dimensional features of forest structure. Surprisingly, we found that flock space use was not consistently associated with any variable, even though available habitat differed both within and across forest types. Overall, the best predictors were elevation and leaf area density within the subcanopy (16–25 m), yet most flock foraging occurred in the midstory (6–15 m). Together, these results indicate that while flocks may have certain habitat preferences, these preferences are flexible or idiosyncratic and do not correspond to a specific vertical profile. For example, flocks spent a disproportionate amount of time in low elevations when available, but not all flocks had access to low‐lying areas within their home ranges. Although other studies show flock size and diversity can be highly sensitive to habitat disturbance, mixed‐species flocks demonstrate remarkable plasticity as a unit, virtually saturating undisturbed and disturbed forest at our site, as long as regeneration has passed a certain threshold. [ABSTRACT FROM AUTHOR]

The Indian Ocean tsunami in 2004 revealed the inferiority of hard engineering solutions in coastal protection and provided sound evidence over the potential of coastal vegetation, particularly mangroves in protecting the coast against erosion, tropical storm surges, and occasional natural calamities like tsunamis. The present study was initiated therefore to determine the extent to which mangroves could be used to protect the coasts against damage by tsunamis. The structure of mangrove vegetation at Kirinda, Kalametiya, and Rekawa in Sri Lanka that resisted tsunami waves for varying extents in 2004 was studied in detail to discern the wave attenuation function of mangrove vegetation. Vegetation structure is a salient factor that contributes to reduction of the impact of natural disturbances to which mangrove ecosystems are vulnerable. The current study highlights that mangrove parameters such as canopy, trunk, and complex root system and wave parameters such incident wave height and inundation distance play vital role in mangroves-induced wave attenuation. The study found that tsunami run-up height and tsunami inundation distance were negatively correlated with tree volume, forest width and tree height whereas that was positively correlated with porosity of the mangrove vegetation. Depth of sedimentation caused by tsunami waves decreased across the mangrove vegetation from the proximal end (in relation to the advancing wave) to the distal end at all mangrove study sites indicating the progressive dissipation of energy of the wave. The mangrove plant communities comprised of Avicennia marina, Ceriops tagal, Excoecaria agallocha and, Rhizophora mucronata evidently, have served as natural coastal barriers and contribute to mitigate impacts of natural disturbances such as tsunamis and tropical storms. As such our study revealed that the effectiveness of coastal bio-shields is based on the make-up of the coastal forests. [ABSTRACT FROM AUTHOR]

Vegetation structural complexity (VSC) plays an essential role in the functioning and the stability of fire-prone Mediterranean ecosystems. However, we currently lack knowledge about the effects of increasing fire severity on the VSC spatial variability, as modulated by the plant community type in complex post-fire landscapes. Accordingly, this study explored, for the first time, the effect of fire severity on the VSC of different Mediterranean plant communities one year after fire by leveraging field inventory and Sentinel-1 C-band synthetic aperture radar (SAR) data. The field-evaluated VSC retrieved in post-fire scenarios from Sentinel-1 γ0 VV and VH backscatter data featured high fit (R2 = 0.878) and low predictive error (RMSE = 0.112). Wall-to-wall VSC estimates showed that plant community types strongly modulated the VSC response to increasing fire severity, with this response strongly linked to the regenerative strategies of the dominant species in the community. Moderate and high fire severities had a strong impact, one year after fire, on the VSC of broom shrublands and Scots pine forests, dominated by facultative and obligate seeder species, respectively. In contrast, the fire-induced impacts on VSC were not significantly different between low and moderate fire-severity scenarios in communities dominated by resprouter species, i.e., heathlands and Pyrenean oak forests. [ABSTRACT FROM AUTHOR]

In wild bird populations, the structure of vegetation around nest‐sites can influence the risk of predation of dependent offspring, generating selection for nest‐sites with vegetation characteristics associated with lower predation rates. However, vegetation structure can be difficult to quantify objectively in the field, which might explain why there remains a general lack of understanding of which characteristics are most important in determining predation rates. Airborne laser scanning (ALS) offers a powerful means of measuring vegetation structure at unprecedented resolution. Here, we combined ALS with 11 years of breeding data from a wild population of superb fairy‐wrens Malurus cyaneus in southeastern Australia, a species which nests relatively close to the ground and has high rates of nest and fledgling predation. We derived structural measurements of understorey (0–8 m) vegetation from a contiguous grid of 30 × 30 m resolution cells across our c. 65 hectares study area. We found that cells with nests (nest‐cells) differed in their understorey vegetation structure characteristics compared to unused cells, primarily in having denser vegetation in the lowest layer of the understorey (0–2 m; the 'groundstorey' layer). The average height of understorey vegetation was also lower in cells with nests than in those without nests. However, relationships between understorey vegetation structure characteristics and breeding performance were mixed. Nest success rates decreased with higher volumes of groundstorey vegetation, as did fledgling survival rates, though only in nest‐cells with lower height vegetation. Our results indicate that ALS can identify vegetation characteristics relevant for superb fairy‐wren nest‐site selection, but that nesting preferences are not beneficial under current predation pressures. The study illustrates the potential for using ALS to investigate how ecological conditions affect behaviour and life‐histories in wild animal populations. [ABSTRACT FROM AUTHOR]

Copyright of Biotropica is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A link between the abundance of species and their degree of ecological specialization has previously been suggested within the primate order. Many species of lemurs were only recently described and even basic ecological data are not yet available for them. We investigated the habitat use, abundance, and habitat characteristics of the critically endangered Microcebus gerpi and evaluated potential impacts of vegetation structure and human disturbances on variations in its abundance. We determined abundance by systematic nocturnal surveys along 13 transects that were also used for characterizing the vegetation structure in seven study sites that were widely distributed within its range. Although M. gerpi occurred in all studied lowland rainforest and littoral forest fragments in central eastern Madagascar and therefore has a higher ecological plasticity and wider distribution than previously thought, its actual Area of Occupancy is very small (339.78 km2) due to an extreme degree of habitat fragmentation throughout its range. M. gerpi occurred with a mean encounter rate of 3.04 individuals/km but abundance varied substantially between sites (0.75–4.5 individuals/km). Statistical modeling revealed that the cover of small‐ to medium‐sized trees had a positive impact on the abundance of M. gerpi, whereas a composite disturbance score (CDS), formed on the basis of information on the prominence of fires, cattle, charcoal production and wood extraction inside and around the forest, had a negative impact on abundance. These results suggest that M. gerpi is slightly less threatened than expected because of its larger geographic range, but also that it responds negatively to human disturbances. These findings raise strong conservation concerns and question the long‐term viability of the remaining small and isolated populations of this arboreal solitary forager. Research Highlights: The abundance of Microcebus gerpi varies and is positively impacted by the cover of small‐ to medium‐sized trees, but negatively impacted by a composite score of human activities raising serious conservation concerns.The geographic distribution of M. gerpi comprises the remaining lowland rainforests between the rivers Ivondro and Mangoro in eastern Madagascar.Habitat fragmentation is substantial throughout its range, resulting in a very small Area of Occupancy (339.78 km2) that is concordant with an IUCN categorization as Endangered. [ABSTRACT FROM AUTHOR]

Simple Summary: The coffee berry borer (CBB), the most damaging coffee pest, significantly reduces coffee quality and yields. Azteca ants are known biological control agents of the CBB. Our paper demonstrates that the naturally occurring vegetation connectivity between coffee plants and Azteca nest trees facilitates ant mobility, resource recruitment, and CBB removal services. Promoting habitat conservation and structural complexity in agroecosystems supports ant-mediated ecosystem services and natural pest regulation. Vegetation connectivity is an essential aspect of the habitat complexity that impacts species interactions at local scales. However, agricultural intensification reduces connectivity in agroforestry systems, including coffee agroecosystems, which may hinder the movement of natural enemies and reduce the ecosystem services that they provide. Ants play an important role in regulating the coffee berry borer (CBB), which is the most damaging coffee pest. For arboreal ant communities, the connections between trees are important structures that facilitate ant mobility, resource recruitment, foraging success, and pest control ability. To better understand how connectivity impacts arboreal ants in coffee agroecosystems, we conducted an experiment to assess the impact of artificial (string) and naturally occurring vegetation (vines, leaves, branches) connectivity on Azteca sericeasur behavior on coffee plants. We compared ant activity, resource recruitment, and CBB removal rates across three connectivity treatments connecting coffee plants to A. sericeasur nest trees: vegetation connectivity, string, and control (not connected) treatments. We found higher rates of ant activity, resource recruitment, and CBB removal on plants with naturally occurring vegetation connections to A. sericeasur nest trees. Artificial connectivity (string) increased the rates of resource recruitment and CBB removal but to a lesser extent than vegetation connectivity. Moreover, vegetation connectivity buffered reductions in ant activity with distance from the ant nest tree. These results reinforce how habitat complexity in the form of vegetation connectivity impacts interspecific interactions at the local scale. Our results also suggest that leaving some degree of vegetation connectivity between coffee plants and shade trees can promote ant-mediated biological pest control in coffee systems. [ABSTRACT FROM AUTHOR]

Recent anthropogenic sources and excess usage have immensely threatened the communities and habitat ecology of this region's medicinally and economically significant crops. Therefore, our study aims to evaluate the community structure and related environmental characteristics sustaining Nasturtium officinale communities along the river basin (RB) in Northwest Pakistan, using the clustering procedure (Ward's method) and Redundancy analysis (RDA). From 340 phytosociological plots (34 x 10 = 340), we identified four ecologically distinct assemblages of N. officinale governed by different environmental and anthropogenic factors for the first time. The floristic structure shows the dominance of herbaceous (100%), native (77%), and annual (58.09%) species indicating relatively stable communities; however, the existence of the invasive plants (14%) is perturbing and may cause instability in the future, resulting in the replacement of herbaceous plant species. Likewise, we noticed apparent variations in the environmental factors, i.e., clay percentage (p = 3.1 x 10-5), silt and sand percentage (p< 0.05), organic matter (p< 0.001), phosphorus and potassium (p< 0.05), and heavy metals, i.e., Pb, Zn, and Cd (p< 0.05), indicating their dynamic role in maintaining the structure and composition of these ecologically distinct communities. RDA has also demonstrated the fundamental role of these factors in species-environment correlations and explained the geospatial variability and plants' ecological amplitudes in the Swat River wetland ecosystem. We concluded from this study that N. officinale communities are relatively stable due to their rapid colonization; however, most recent high anthropogenic interventions especially overharvesting and sand mining activities, apart from natural enemies, water deficit, mega-droughts, and recent flood intensification due to climate change scenario, are robust future threats to these communities. Our research highlights the dire need for the sustainable uses and conservation of these critical communities for aesthetics, as food for aquatic macrobiota and humans, enhancing water quality, breeding habitat, fodder crop, and its most promising medicinal properties in the region. [ABSTRACT FROM AUTHOR]

The species – area relationship (SAR) is a common pattern in which diversity increases with the area sampled, but ecosystems are three‐dimensional (3D) and diversity – volume relationships (DVRs) may exist in ecosystems that vary substantially in their vegetation volume. We tested whether forest vegetation volume, as a 3D extension of area in SARs, was a significant predictor of taxonomic (species) and structural (arrangement) diversity in five groups of organisms across the National Ecological Observatory Network (NEON). Vegetation volume and four structural arrangement metrics within the area of NEON plots were measured using NEON's discrete return lidar. Species richness was measured as the number of species within the respective NEON plot sampling area for understory plants, trees, breeding land birds, small mammals, and ground beetles. We found that volume negatively predicted understory plants and positively predicted tree and beetle species richness across the USA forest macrosystem, but not bird and small mammal species richness. Furthermore, volume was a significant predictor of several metrics that describe the internal and external heterogeneity of vegetation in forests (structural arrangement) within the ecosystem across the USA forest macrosystem. There were several significant within site‐level relationships, but not at all sites, between volume and species richness or structural arrangement in organism groups. Our study indicates that previous work that has focused on a 2D conceptualization of habitat can be expanded to 3D habitat space, but that the strength and the positive or negative direction of DVRs may vary taxonomically or geographically. [ABSTRACT FROM AUTHOR]

This study was conducted at Rilagala conservation forest, Nawalapitiya to assess and compare the plant diversity, above ground biomass and carbon stock in the periphery and interior of an isolated sub montane forest in Sri Lanka. All trees above 5 cm Diameter at Breast Height (DBH) in eleven randomly demarcated 25 m × 25 m plots were recorded. Distance up to 100 m from the forest boundary considered as the periphery (8 plots) and over 200 m as the core (3 plots). A total of 1,583 trees belonging to 29 species were recorded and aboveground biomass (AGB) and carbon stocks were calculated using allometric equations. The tree diversity of each plot was calculated using the Shannon diversity index (H'). Results were statistically analysed using single factor ANOVA. The species richness and H' were the highest at the periphery (n=23, H'= 2.55) while the lowest at forest interior (n=11, H'= 1.97). The highest tree density was recorded at periphery (2,992 trees ha-1) and it decreased to 1,408 trees ha-1 towards the core. The average DBH was 8.5 ± 3.33 cm and it increased towards the forest interior (9.7 ± 4.51 cm) from the periphery (7.2 ± 3.74 cm). Estimated aboveground biomass ranged from 63.99 - 108.13 Mg ha-1 with a mean of 82.53 ± 14.39 Mg ha-1. The above ground C stock was estimated from 31.99 - 54.07 Mg ha-1 with a mean of 41.26 ± 7.2 Mg ha-1. However, there was no significant difference between forest periphery and core in variables, except species richness (p<0.05). The study revealed that the diversity and density of trees decreased towards the forest interior and vice versa was recorded for DBH, AGB and carbon stock. The study highlights the importance of conserving isolated tropical sub montane forest patches for carbon sequestration. [ABSTRACT FROM AUTHOR]

A considerable area of land has been turned into a built surface in Ethiopia. Flooding is one of the destructive consequences of such land conversion in the urban centers of the country. Thus, this research aimed at evaluating the effectiveness of urban green infrastructures to alleviate the impacts of runoff in the urbanized part of Hawassa City, Ethiopia. The i-Tree Eco model with pre-stratified random sampling techniques was employed to analyze the hydrological benefits of green infrastructure by considering the vegetation structure and land surface cover variables. Also, the spatial map that shows annually avoided runoff was created using the spatial interpolation method in the ArcGIS software. The outcome of the model-based analysis shows that 576,224 trees were recorded, which contributes to cover 20.7% of the city's total area. These trees intercepted 137,632.8 m3 year−1 rainwater and avoided 288,372 m3 year−1 runoff, economically valued at $ 680,558/year. However, the existing green infrastructures of the city had different performances in terms of water interception and runoff reduction efficiency, according to the morpho-functional characteristics of trees. Those green infrastructures with large trees, high leaf areas, and a high number of broadleaved trees were more efficient. Runoff reduction efficiency of the city could be maximized through the incorporation of adequate green infrastructure coverage at the urban planning stage and proper execution of structural plans. Hence, this research is expected to help planners and policymakers rethink the integration of green infrastructure in the spatial planning of cities and towns in Ethiopia. [ABSTRACT FROM AUTHOR]

Mangrove forests serve a substantial part in coastal areas as highcarbon-storage woody vegetation ecosystems that grow on muddy and anaerobic soils. This study determined the species composition and estimated the biomass production and storage of carbon in Ambon Bay mangrove forests. Vegetation surveys for species composition were conducted using the square plot technique by making standard observation plots for density, frequency, dominance, and important value index data analysis. We used Allometric equations and the Loss-on-ignition method to calculate the biomass and soil carbon. Vegetation surveys revealed eight species of treehabitus mangroves, and Sonneratia alba was a mono-dominant species with an important value index of more than 100%. The study revealed the highest average potential of biomass and carbon in Passo Village with AGB 280.47±168.94 Mg ha-1, BGB 83.06±55.1 Mg ha-1, and sediment carbon 320.03±106.97 Mg C ha-1. The carbon stock of the mangrove forest in Ambon Bay was estimated at 400.67±166.25 Mg C ha-1. We conclude that mangrove forest carbon stores in Ambon Bay had relatively high values. Passo Village has the largest carbon store compared to other locations in the Ambon Bay mangrove forest. [ABSTRACT FROM AUTHOR]

Climate oscillations are becoming more extreme, and mangroves may be more susceptible to changes in physical conditions that can lead to mass diebacks. The current study analysed the impacts of an extreme weather event in the Cananéia-Iguape Coastal System, southeast Brazilian mangroves and the condition of the area over three years. We used a multiproxy approach, including analyses of climatic attributes, structural vegetation, and vegetation indices. Damage caused by a strong storm and hail damage had a severe impact on mangrove areas. A meteorological station installed in the mangrove since 2008 recorded a maximum wind gust of 58 km·h−1 on 30 May 2019. On the Beaufort scale, this speed is classified as strong wind. After the extreme weather event, there were catastrophic impacts on the mangrove, with more than 90% dead trunks. Vegetation indices were reduced, indicating intense changes. The NDVI of the mangroves was reduced from 0.72 to 0.35. The LAI confirmed this premise, with a reduction from 4.25 to 0.63. After three years, natural recovery had not occurred. Extreme weather events have continued to occur along coasts, drastically altering the landscape. Mangroves have been affected by these events, and depending on the state of health of the forests, may have difficulties in recovery. [ABSTRACT FROM AUTHOR]

Copyright of Ecologia Austral is the property of Asociacion Argentina de Ecologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Fire plays a key role in structuring biotic communities around the world. In fire-prone regions, many plant species have acquired adaptive traits such as obligate seeders and resprouters that help them to survive, reproduce, and persist after fire disturbances. Seeder and resprouting species have different short-term responses to fire. Obligate seeders have faster growth rates, greater carbon allocation to reproduction, shorter life cycles, and lower shade tolerance than resprouters. A few years after fire, obligate seeders are expected to be more abundant than resprouter species within post-fire plant communities. We examined this hypothesis in burned pine plantations located along the African rim of the Western Mediterranean Basin. In this region, pine plantation is the commonest forestry practice, and such woodlands have undergone frequent fires during the last decades. Here, we describe habitat structure and plant species composition in burned and unburned plots located in four independently burned sites. Burned and unburned plots were structurally different, with the shrub and grass covers expanding after fire. In terms of functional plant composition, obligate seeders were more abundant than resprouters in burned pine plantations. The stronger short-term response of obligate seeders compared to resprouters can be related to the faster capacity of obligate seeders to respond to fire. Contrast in fire response between the two functional plant groups needs to be addressed in conservation planning to ensure the preservation of biodiversity in a future scenario of change in fire regime. [ABSTRACT FROM AUTHOR]

Green areas are important places for biodiversity conservation within cities, but their vegetation is affected by various anthropogenic factors. This study used an exploratory approach to examine the influence of urbanisation and air pollution-related factors on the indicators for the composition and structure of vegetation in an urban area in northeast Mexico. Based on the spatial analysis of the major air pollutants, four sampling categories were delimited (rural, low, moderate and high urbanisation). The differences between categories, based on vegetation structure, were determined using non-parametric Kruskal-Wallis tests. The Importance Value was calculated for the species. The floristic similarity was compared using NMDS and PERMANOVA unidirectional. The relationship between environmental variables and abundance of species was evaluated using CCA. One hundred and ten plant species were collected, including ten alien species. The highest abundance and species richness were registered in the rural site. The general tendency of vegetation structure is to plants decreasing with respect to the increase in the levels of urbanisation and air pollution present in the study area. The association between the environmental variables and plant communities along the urbanisation gradient was significant, being the relative humidity, the particles lower than 2.5 μm, the dew point and the heat index as the most important variables. The understanding of the nature and variability of vegetation within green areas contributes to increasing our knowledge about the distribution of the environmental services they provide and the composition of the faunal communities that depend on them. For this reason, this study relates the plants of a specific area of northeast Mexico with the environmental quality present in an urban area. [ABSTRACT FROM AUTHOR]

The present study reviews the impact of mechanical interventions, and controlled burning combined with grazing in the Mediterranean-climate regions (MCRs) of the world. Relevant studies were searched for in the Web of Science database. Additional studies were located in the citations of these publications, and in a local database. Finally, 26 studies were included in this review. Since 1978, several other relevant studies have emerged at a rate of 24% in a 5-year time step. The studies have focused on the effects of combined grazing with other management tools on vegetation structure (18 publications), biomass productivity (16 publications), and floristic diversity (12 publications). The results were analyzed for (a) sites and treatments and (b) effects on plant structure, productivity and floristic diversity. Herbaceous forage increased after a reduction in shrub cover. Shrubs tended to recover in the grazed pastures. Vegetation height was reduced in almost in all cases according to available data. Despite its potential recovery, shrub biomass was affected by grazing in most cases. The impact of subsequent grazing was mixed regarding floristic diversity. Grazing is a useful tool for landscape management in MCRs, but the proper way to combine it with other interventions depends on the management goals. [ABSTRACT FROM AUTHOR]

Sleep is an important aspect of great ape life; these animals build sleeping platforms every night. In a community of chimpanzees, each subgroup selects a sleeping site where each individual builds a sleeping platform, mostly on a tree. Previous studies have measured the heights of sleeping platforms and sleeping trees to test the predation avoidance and thermoregulation hypotheses of sleeping site selection. However, it remains unclear how components of vegetation structure (vertical and horizontal) together determine the selection of sleeping sites by chimpanzees. Using botanical inventories around sleeping sites in a tropical rainforest of Cameroon, we found that chimpanzees preferentially sleep in trees measuring 40–50 cm in diameter. Regarding height, on average, sleeping trees measured 26 m and sleeping platforms were built at 16 m. To build sleeping platforms, chimpanzees preferred four tree species, which represent less than 3% of tree species in the study area. We demonstrate that the variation in abundance of tree species and the vertical and horizontal structure of the vegetation drive chimpanzee sleeping site selection. It was previously thought that preference for vegetation types was the driver of sleeping site selection in chimpanzees. However, results from this study indicate that the importance of vegetation types in sleeping site selection depends on their botanical characteristics including the variation in tree size, the abundance of all trees, the abundance of sleeping trees, and the occurrence of preferred sleeping tree species, which predict sleeping site selection. The height and diameter of trees are considered by chimpanzees when selecting a particular tree for sleeping and when selecting a site with a specific vertical structure. In addition to tree height, the abundance of smaller neighboring trees may also play a role in the chimpanzee antipredation strategy. Our results demonstrate that chimpanzees consider several vegetation parameters to establish sleeping sites. Highlights: Vertical and horizontal vegetation structures are the main determinants of sleeping site selection in chimpanzees.Chimpanzees select sleeping sites with a high abundance of particular tree species (Heisteria parvifolia, Sorindeia grandifolia, Uapaca guineensis, Uapaca vanhouttei) that have specific diameters (diameter at breast height between 40 and 50 cm) and heights (average = 25.68 m, SD = 8.86 m).Studying sleeping site selection in chimpanzees based on vegetation structure may contribute to the understanding of the mechanism of predator avoidance. [ABSTRACT FROM AUTHOR]

Classic ecological research into the determinants of biodiversity patterns emphasised the important role of three‐dimensional (3D) vegetation heterogeneity. Yet, measuring vegetation structure across large areas has historically been difficult. A growing focus on large‐scale research questions has caused local vegetation heterogeneity to be overlooked compared with more readily accessible habitat metrics from, for example, land cover maps.Using newly available 3D vegetation data, we investigated the relative importance of habitat and vegetation heterogeneity for explaining patterns of bird species richness and composition across Denmark (42,394 km2).We used standardised, repeated point counts of birds conducted by volunteers across Denmark alongside metrics of habitat availability from land‐cover maps and vegetation structure from rasterised LiDAR data (10 m resolution). We used random forest models to relate species richness to environmental features and considered trait‐specific responses by grouping species by nesting behaviour, habitat preference and primary lifestyle. Finally, we evaluated the role of habitat and vegetation heterogeneity metrics in explaining local bird assemblage composition.Overall, vegetation structure was equally as important as habitat availability for explaining bird richness patterns. However, we did not find a consistent positive relationship between species richness and habitat or vegetation heterogeneity; instead, functional groups displayed individual responses to habitat features. Meanwhile, habitat availability had the strongest correlation with the patterns of bird assemblage composition.Our results show how LiDAR and land cover data complement one another to provide insights into different facets of biodiversity patterns and demonstrate the potential of combining remote sensing and structured citizen science programmes for biodiversity research. With the growing coverage of LiDAR surveys, we are witnessing a revolution of highly detailed 3D data that will allow us to integrate vegetation heterogeneity into studies at large spatial extents and advance our understanding of species' physical niches. [ABSTRACT FROM AUTHOR]

The distribution of birds in the tropical mountains is important not only for testing fundamental scientific hypotheses, but also for bird conservation. In order to obtain knowledge on bird community structure within the tropical highland ecosystem, we used ground-to-canopy mist nets to assess bird species distribution along a vertical ground-to-canopy gradient for two elevational bands on Mount Cameroon. The study area included lowland forest (Drink Garri, 650 m a.s.l.) and montane forest (Mann's Spring, 2200 m a.s.l.). We mist netted a total of 2658 individuals, including recaptures, belonging to 118 species from 50 genera. NLAG (net location above the ground), vegetation cover and locality significantly affected the bird communities. The composition of avian communities strongly differed between the two elevational bands. Species diversity considerably decreased with NLAG in both localities and increased with increased vegetation cover at the low elevation site. Species dietary guilds were significantly influenced by the seasonality, elevation, NLAG and vegetation cover. For most of the feeding guilds included in the study (frugivores, omnivores, insectivores, granivores and nectarivores), we found a negative correlation between the abundances and vegetation cover. Meanwhile, percentages of abundance of frugivores, nectarivores and omnivores showed a positive correlation with NLAG. We discuss the substantial changes in feeding guild structure along a vertical gradient and between two elevational bands. In conclusion, Mount Cameroon's forest vegetation structure differs between two elevational bands and along vertical gradients from ground to canopy, considerably affecting the bird community structure. [ABSTRACT FROM AUTHOR]

Context. Habitat loss is a global problem and in Fiji >50% of the land area once covered by forests has been converted to grasslands and agricultural land. About 99% of Fiji's endemic biodiversity and 80% of the land bird species have been identified as forest species. Aims. In this study, we compare forest and grassland sites and test for consistency in avian diversity, abundance, foraging guild, and distribution status (endemic, native, introduced to Fiji) over a 5-year period (2016-2020). Methods. We surveyed bird communities using the point count method with a 100 m radius and 7-min observation period per site. Key results. A one-way analysis of similarities (ANOSIM) analysis showed significant differences in species composition and bird abundance between the forested habitats and grassland habitats. A general linear model test showed significant differences in foraging guild composition and distribution status between forested and grassland habitats. There were no significant differences between the three forested sites (primary montane forest, secondary old-growth forest, old-growth mahogany plantations with regenerating native species), while grassland sites had stronger annual change in species composition. Implications. Forest cover, irrespective of whether these forests are of primary or secondary nature, therefore plays an important role in maintaining the native and endemic land bird species and other biodiversity in oceanic island ecosystems such as Viti Levu Island, Fiji. [ABSTRACT FROM AUTHOR]

This study describes the structure and phenology of Sahelian rangelands during the rainy season. It was undertaken on a grazed plot and a fenced plot. Measurements were taken every 10 days over two rainy seasons between July and October 2018 and between August and October 2019. The measurements included the phenological stage, the vegetative and flowering height, the coverage, and the phytomass. The results showed that phytomass did not systematically differ between grazed and fenced plots. Flowering started as early as mid-July, but most of the plants flowered in early October. Flowering and fruiting occurred earlier (based on the number of days after the first rain) in the late rainy season (2019) than in the early one (2018). These stages reached their peak in October; senescence began in October. Vegetative height, reproductive height, and coverage were similar between the two years. Height peaks were similar, but they were reached earlier (based on the number of days after the first rain) in the late rainy season than in the early one. Coverage peaks were similar (59.8% in the early rainy season vs. 65.8% in the late one). Vegetative height (around 30 cm), reproductive height (around 36 cm), and coverage (around 60%) reached their maximum in October, but reproductive height was greater than vegetative height. These parameters were lower at the grazed site compared to the fenced site, and flowering started earlier at the grazed site. The pasture had a negative impact on coverage, height, and early flowering. Structure and phenology were more sensitive than to changes in rainfall between years. Phenology results will help determine the best time to harvest the phytomass (phytomass stock), as the nutritional quality of the forage is known to decrease after fruiting. [ABSTRACT FROM AUTHOR]

A key aspect of nature conservation is knowledge of which aspects of nature to conserve or restore to favor the characteristic diversity of plants in a given area. Here, we used a large plant dataset with >40 000 plots combined with airborne laser scanning (lidar) data to reveal the local characteristics of habitats having a high plant dark diversity—that is, absence of suitable species—at national extent (>43 000 km2). Such habitats have potential for reaching high realized diversity levels and hence are important in a conservation context. We calculated 10 different lidar based metrics (both terrain and vegetation structure) and combined these with seven different field‐based measures (soil chemistry and species indicators). We then used Integrated Nested Laplace Approximation for modelling plant dark diversity across 33 North European habitat types (open landscapes and forests) selected by the European communities to be important. In open habitat types high‐dark‐diversity habitats had relatively low pH, high nitrogen content, tall homogenous vegetation, and overall relatively homogenous terrains (high terrain openness) although with a rather high degree of local microtopographical variations. High‐dark‐diversity habitats in forests had relatively tall vegetation, few natural‐forest indicators, low potential solar radiation input and a low cover of small woody plants. Our results highlight important vegetation, terrain‐ and soil‐related factors that managers and policymakers should be aware of in conservation and restoration projects to ensure a natural plant diversity, for example low nutrient loads, natural microtopography and possibly also open forests with old‐growth elements such as dead wood and rot attacks. [ABSTRACT FROM AUTHOR]

In forestry research, for forest inventories or other applications which require accurate 3D information on the forest structure, a Terrestrial Laser Scanner (TLS) is an efficient tool for vegetation structure estimation. Light Detection and Ranging (LiDAR) can even provide high-resolution information in tree canopies due to its high penetration capability. Depending on the forest plot size, tree density, and structure, multiple TLS scans are acquired to cover the forest plot in all directions to avoid any voids in the dataset that are generated. However, while increasing the number of scans, we often tend to increase the data redundancy as we keep acquiring data for the same region from multiple scan positions. In this research, an extensive qualitative analysis was carried out to examine the capability and efficiency of TLS to generate canopy top points in six different scanning combinations. A total of nine scans were acquired for each forest plot, and from these nine scans, we made six different combinations to evaluate the 3D vegetation structure derived from each scan combination, such as Center Scans (CS), Four Corners Scans (FCS), Four Corners with Center Scans (FCwCS), Four Sides Center Scans (FSCS), Four Sides Center with Center Scans (FSCwCS), and All Nine Scans (ANS). We considered eight forest plots with dimensions of 25 m × 25 m, of which four plots were of medium tree density, and the other four had a high tree density. The forest plots are located in central Slovakia; European beech was the dominant tree species with a mixture of European oak, Silver fir, Norway spruce, and European hornbeam. Altogether, 487 trees were considered for this research. The quantification of tree canopy top points obtained from a TLS point cloud is very crucial as the point cloud is used to derive the Digital Surface Model (DSM) and Canopy Height Model (CHM). We also performed a statistical evaluation by calculating the differences in the canopy top points between ANS and the five other combinations and found that the most significantly different combination was FSCwCS respective to ANS. The Root Mean Squared Error (RMSE) of the deviations in tree canopy top points obtained for plots TLS_Plot1 and TLS_Plot2 ranged from 0.89 m to 14.98 m and 0.61 m to 7.78 m, respectively. The relative Root Mean Squared Error (rRMSE) obtained for plots TLS_Plot1 and TLS_Plot2 ranged from 0.15% to 2.48% and 0.096% to 1.22%, respectively. [ABSTRACT FROM AUTHOR]

Background: Vegetation structure is defined as the temporal and spatial distribution of plant species in a particular site. Vegetation structure includes vertical and horizontal distribution and has been widely used as an indicator of successional changes. Ecological succession plays an essential role in the determination of the mechanisms that structure plant communities under anthropogenic disturbances. After an anthropogenic disturbance, such as grazing, forests follow changes in the original composition and vegetation structure, which eventually could restore some of their attributes to become mature forests again. To know how the time of abandonment affects woody plant communities, we ask the following questions: (1) How does the species richness, diversity, and vertical structure (A index) change concerning the time of abandonment? (2) Are species similarities among woody vegetation communities determined by land abandonment? (3) Which woody species have the highest ecological importance in each successional stage? Methods: We explored how successional stages after land abandonment mediated the species richness, species diversity (alpha and beta), and ecological importance value index on four areas of Tamaulipan thornscrub. We selected four areas that differed in time of abandonment: 10, 20, 30, and >30 years. The first three areas were used for cattle grazing, whereas the >30-year area was selected as a control since it does not have a record of disturbance by cattle grazing or agriculture. During the summer of 2012, we randomly established four square plots (40 m x 40 m) in each area, separated at least 200 m from each other. In each plot, we recorded all woody individuals per species with a basal diameter >1 cm at 10 cm above ground level. We estimated species richness indices, species diversity (alpha and beta), and ecological importance value index. Results: We recorded 27 woody species belonging to 23 genera and 15 families. Fabaceae accounted for 40% of the species. Acacia farnesiana was the most important and abundant species in the first three successional stages. We suggested that older successional stages of Tamaulipan thornscrub promote woody plant communities, characterized by a higher complex structure than younger communities. We observed the highest species similarity between the sites with a closer time of abandonment, while the lowest similarity was shown between the sites with extreme time of abandonment. We conclude that Tamaulipan thornscrub shows a similar trend of ecological succession to other dry forests and the time of abandonment has a high mediation on plant dynamics in the Tamaulipan thornscrub. Also, we stand out the importance of secondary forests for Tamaulipan thornscrub woody plant communities. Finally, we recommended future studies include aspects of regeneration speed, the proximity of mature vegetation, and the interactions of plants with their seed dispersers. [ABSTRACT FROM AUTHOR]

Naturally regenerating forests or secondary forests (SFs) are a promising strategy for restoring large expanses of tropical forests at low cost and with high environmental benefits. This expectation is supported by the high resilience of tropical forests after natural disturbances, yet this resilience can be severely reduced by human impacts. Assessing the characteristics of SFs and their ecological integrity (EI) is essential to evaluating their role for conservation, restoration, and provisioning of ecosystem services. In this study, we aim to propose a concept and indicators that allow the assessment and classification of the EI of SFs. To this end, we review the literature to assess how EI has been addressed in different ecosystems and which indicators of EI are most commonly used for tropical forests. Building upon this knowledge we propose a modification of the concept of EI to embrace SFs and suggest indicators of EI that can be applied to different successional stages or stand ages. Additionally, we relate these indicators to ecosystem service provision in order to support the practical application of the theory. EI is generally defined as the ability of ecosystems to support and maintain composition, structure and function similar to the reference conditions of an undisturbed ecosystem. This definition does not consider the temporal dynamics of recovering ecosystems, such as SFs. Therefore, we suggest incorporation of an optimal successional trajectory as a reference in addition to the old‐growth forest reference. The optimal successional trajectory represents the maximum EI that can be attained at each successional stage in a given region and enables the evaluation of EI at any given age class. We further suggest a list of indicators, the main ones being: compositional indicators (species diversity/richness and indicator species); structural indicators (basal area, heterogeneity of basal area and canopy cover); function indicators (tree growth and mortality); and landscape proxies (landscape heterogeneity, landscape connectivity). Finally, we discuss how this approach can assist in defining the value of SF patches to provide ecosystem services, restore forests and contribute to ecosystem conservation. [ABSTRACT FROM AUTHOR]

Arable land covers a large part of the European landscape, and its biodiversity is declining rapidly due to agricultural intensification. Among the most threatened groups of organisms are insectivorous ground-foraging farmland birds. To reverse their decline, it is necessary to understand the impact of agriculture on the factors potentially shaping their populations. This study therefore evaluates the invertebrate food availability and vegetation structure of three widespread crops—wheat, maize and rapeseed—during their breeding. This research took place in Slovakia, the country with the largest average field size in the EU. Wheat overlapped bird habitat preferences for the longest part of their breeding season by vegetation structure, but it also had the most limited food supply due to frequent treatment with insecticides. Maize and rapeseed provided higher invertebrate abundance and biomass, but their stands created unsuitable vegetation structures for farmland bird nesting and foraging over a major part of the breeding season. The food supply improved closer to the field edges, but the birds' ability to use these benefits could be considerably limited by the large field sizes. Therefore, conservation measures should include reduction of field size and insecticide application to improve the food supply and switch to spring sowing to improve the vegetation structure. [ABSTRACT FROM AUTHOR]

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Questions: Knowledge of how extreme drought events induce plant dieback and, eventually, plant mortality, may improve our forecasting of ecosystem change according to future climate projections, especially in Mediterranean drylands. In them, shrublands are the main vegetation communities in transition areas from a subhumid to semi‐arid climate. This study analyzed differences in plant dieback after an unusual drought in 2014 and identified their main underlying factors in relation to three groups of explanatory variables: water availability, soil properties and vegetation structure attributes. Location: Four Mediterranean shrublands along a climatic gradient in SE Spain. Methods: At each experimental field site, we sampled a pool of vegetation structure characteristics, soil depth and soil surface properties, and we also determined water availability by continuously monitoring soil moisture and the microclimate conditions. Results: The climatic analysis showed that there was an extreme drought event in 2014, which was below the first percentile of the driest years. Under such conditions, vegetation dieback occurred at all the study sites. However, plant dieback differed between sites and plant biotypes. Subshrubs were the main affected biotype, with diebacks close to 60% at the driest sites, and up to 40% dieback for shrubs depending on their vertical development. Relative extractable water and bare soil surface cover were the best explanatory variables of plant community dieback but changed between plant biotypes. Vegetation structure variables related to plant vertical development (leaf area index [LAI], plant height, phytovolume) were significant explanatory variables of plant dieback in shrubs, subshrubs and grasses. Consecutive dry days fitted the best model to explain subshrub dieback. Conclusions: We found that rainfall pattern rather than total annual rainfall was the climatic factor that best determined water availability for plants in Mediterranean drylands. These results also pointed out the relevance of plant structure and soil properties for explaining ecosystem responses to extreme drought. [ABSTRACT FROM AUTHOR]

Risk of predation is one of the main constraints of small mammal distribution and foraging activity. Aside from numerical effects on population size due to the presence and abundance of predators, indirect cues, such as vegetation structure and moonlight, determine patterns of activity and microhabitat use by small mammals. Indirect cues are expected to interact, as shading provided by vegetation can suppress the effects of changing moonlight. We analyzed the effects of moonlight levels on the activity patterns of three common small mammal species in Mediterranean habitats, and tested whether moonlight effects were modulated by shadowing associated with the development of tall vegetation due to spontaneous afforestation following land abandonment. A. sylvaticus, a strictly nocturnal species, decreased activity under moonlight with no interactive effects of vegetation cover. C. russula showed no activity change with moonlight levels and M. spretus increased activity, although activity in both species was mostly determined by vegetation cover, that favored it. The effects of moonlight on small mammal activity were not homogeneous among species, nor were the interactive effects of man-made gradients of habitat structure, a fact that will produce community changes along vegetation gradients mediated by varying fear landscapes. [ABSTRACT FROM AUTHOR]

The urban climate is receiving increased attention mainly due to climate change. There are several ways to mitigate the urban climate, but green spaces have an advantage over other cooling systems because, in addition to their climate function, they provide several other ecosystem services that enhance the sustainability of urban systems. The cooling effect of green spaces varies depending on their species composition, the structure of the vegetation, the size and shape of the green spaces or the specific characteristics of the plants. Therefore, the exact quantification of urban green space's cooling effect is of critical importance in order to be effectively applied in urban planning as a measure of climate change adaptation. In this paper, we quantified the difference in the cooling effect between urban green spaces depending on their vegetation structure (grass versus trees) and their size, and assessed to what distance from the urban green space its cooling effect can be observed. Urban green spaces were identified using Landsat orthophotomosaic and airborne laser scanning. The urban temperature was calculated as the land surface temperature (LST) from Landsat data using a single-channel method. To quantify differences in the magnitude of the cooling effect of green spaces and the distance from the edge of the green space over which the cooling effect occurs, we used a one-way analysis of variance and regression analyses. Our results show that the cooling intensity, as well as the cooling distance, are dependent on the size and structure of the green space. The most significant cooling effect is provided by large green tree spaces, where the cooling intensity (difference of LST compared to an urban area without vegetation) was almost 4.5 °C on average (maximum almost 6 °C) and the cooling distance was significant up to 90 m (less significantly up to 180 m). Large grass spaces and medium tree spaces have similar effects, with a higher cooling intensity (2.9 °C versus 2.5 °C on average) however, the cooling effect extends to a greater distance (up to 90 m) for medium tree spaces compared to large grass spaces, where the cooling effect only extends to 30–60 m. Small areas with trees and medium and small grass areas without trees have an average cooling intensity below 2 °C. [ABSTRACT FROM AUTHOR]