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In permafrost regions, the strong spatial and temporal variability in soil temperature cannot be explained by the weather forcing only. Understanding the local heterogeneity of soil thermal dynamics and their controls is essential to understand how permafrost systems respond to climate change and to develop process-based models or remote sensing products for predicting soil temperature. In this study, we analyzed soil temperature dynamics and their controls in a discontinuous permafrost region on the Seward Peninsula, Alaska. We acquired one-year temperature time series at multiple depths (at 5 or 10 cm intervals up to 85 cm depth) at 45 discrete locations across a 2.3 km2 watershed. We observed a larger spatial variability in winter temperatures than that in summer temperatures at all depths, with the former controlling most of the spatial variability in mean annual temperatures. We also observed a strong correlation between mean annual ground temperature at a depth of 85 cm and mean annual or winter season ground surface temperature across the 45 locations. We demonstrate that soils classified as cold, intermediate, or warm using hierarchical clustering of full-year temperature data closely match their co-located vegetation (graminoid tundra, dwarf shrub tundra, and tall shrub tundra, respectively). We show that the spatial heterogeneity in soil temperature is primarily driven by spatial heterogeneity in snow cover, which induces variable winter insulation and soil thermal diffusivity. These effects further extend to the subsequent summer by causing variable latent heat exchanges. Finally, we discuss the challenges of predicting soil temperatures from snow depth and vegetation height alone by considering the complexity observed in the field data and reproduced in a model sensitivity analysis.

We present a representation of nitrogen and phosphorus cycling in the Functionally Assembled Terrestrial Ecosystem Simulator, a demographic vegetation model within the Energy Exascale Earth System land model. This representation is modular, and designed to allow testing of multiple hypothetical approaches for carbon-nutrient coupling in plants. Novel model hypotheses introduced in this work include, (a) the controls on plant acquisition of aqueous mineralized nutrients in the soil and (b) fairly straight forward methods of allocating nutrients to specific plant organs and their losses through live plant turnover as well as litter fluxes generated through plant mortality. This combines the new with pre-existing hypotheses (such as nitrogen fixation and soil decomposition) into a system that can accommodate plant-soil dynamics for a large number of size- and functional-type-resolved plant cohorts within a time-since-disturbance-resolved ecosystem. Root uptake of nutrients is governed by fine root biomass, and plants vary in their fine root biomass allocation in order to balance carbon and nutrient limitations to growth. We test the sensitivity of the model to a wide range of parameter variations and structural representations, and in the context of observations at Barro Colorado Island, Panama. A key model prediction is that plants in the high-light-availability canopy positions allocate more carbon to fine roots than plants in low-light understory environments, given the widely different carbon versus nutrient constraints of these two niches within a given ecosystem. This model provides a basis for exploring carbon-nutrient coupling with vegetation demography within Earth system models.

The North Campus Open Space (NCOS) restoration project has created more than 40 acres of estuarine and palustrine wetlands that historically comprised the upper portion of Devereux Slough that was filled in the mid-1960s to create the Ocean Meadows golf course. The project also restored more than 60 acres of upland habitats that include native grassland, coastal sage scrub, riparian, oak chaparral woodland, vernal pools and patches of annual wildflowers in clay and sandy soils. This report summarizes the results from monitoring native and non-native plants, birds, small mammals, aquatic invertebrates, tree growth, and hydrological functions.

Aim: The distribution of birds among islands is thought to be regulated by island physical geography (i.e. island area, isolation and latitude). In contrast, work on continents indicates that bird diversity is often regulated by plant diversity. Consequently, the (statistical) direct and indirect effects of physical geography on island bird distribution are poorly understood. We investigated the relative roles of physical geography and vegetation in determining island bird diversity in the South West Pacific at two taxonomic scales of resolution: total bird diversity and bird diversity within functional guilds. Location: Eleven archipelagos in the South West Pacific. Taxon: Land birds. Methods: We created a dataset characterising total and functional guild diversity for land birds and seed plants (i.e. Spermatophytes) among archipelagos. We then used mediation analysis to disentangle the direct and indirect (i.e. mediated) effects of physical geography and vegetation on bird diversity. Results: On a broad taxonomic scale, total bird diversity was directly determined by total plant diversity, not the area, isolation or latitude of islands. On a fine taxonomic scale results differed between functional guilds. The diversity of herbivorous and frugivorous birds was directly determined by physical geography rather than plant total and trait diversity. Woody and herbaceous plant species diversity mediated the effect of physical geography on forest‐dwelling, above ground nesting and ground nesting bird diversity. Granivorous, nectarivorous and grassland‐dwelling bird diversities were unrelated to both physical geography and herbaceous plant diversity. Main Conclusions: Physical geography and vegetation can have both direct and indirect effects on island bird diversity. Furthermore, relationships between physical geography, vegetation and bird diversity can vary markedly among functional guilds. [ABSTRACT FROM AUTHOR]

The shear strength of rooted soils depends on the principal stress direction owing to the anisotropy in the soil structure and root system. Existing failure criteria cannot describe the strength anisotropy of rooted soils under general loading conditions because they are mainly based on the test results of direct shear. This study presents a new generalised three-dimensional anisotropic failure criterion for rooted soils. The model employs the projection of two independent microstructure fabric tensors (soil fabric and root network) on the stress tensor. Twenty-four drained triaxial compression and extension tests were carried out to measure the strength anisotropy of silty sand vegetated with vetiver grass (Chrysopogon zizanioides L.) at different overconsolidation ratios and calibrate the material parameters for the proposed criterion. Anisotropies of both cohesion and friction angle exist in rooted soil. Roots contribute mainly to the increase in cohesion (hence root cohesion) from most of the direct shear test data. Roots with predominant orientation aligning in the tensile strain direction contribute the most to soil strength. In the case of vetiver grass, which has a taproot system, their roots show the strongest reinforcement effect in the conventional triaxial extension path, in which the maximum portion of the roots is subjected to tension. [ABSTRACT FROM AUTHOR]

African elephants (Loxodonta africana) play a significant role in the modification of their habitat, foremost by decreasing woody vegetation cover and density. Little is known regarding the effects of elephant habitat disturbance (EHD) on medium-to-large mammal and bird communities. While the intermediate disturbance hypothesis (IDH) predicts species richness and diversity will be maximised in areas of moderate EHD, high levels of EHD could result in habitat degradation and negatively impact certain wildlife communities. To examine this relationship, we compared mammal and avian community assemblages, richness, and diversity across differing severities (low, medium, high) of elephant disturbed habitats (woodland, shrubland, and mixed wood/shrubland) within Rukinga Wildlife Sanctuary (RWS) in south-eastern Kenya. From June–November 2022, we collected wildlife detection data via driving transects and surveyed EHD through observation of elephant tree damage. While EHD level did impact community assemblage, possibly through vegetation modification and/or increased habitat heterogeneity, EHD had no negative impacts on species richness and diversity in the three habitat types. In contrast to our IDH prediction, richness and diversity were highest in high EHD areas within shrubland habitat and showed no difference across EHD levels for the other two habitats. Overall, this study provides evidence that elephants in RWS are not disturbing habitats to an extent that negatively impacts sanctuary viability, and at least for shrub habitat appear to enhance it. Additionally, smaller wildlife habitats may be able to mitigate lasting elephant overpopulation damages through increased connectivity to other protected areas. [ABSTRACT FROM AUTHOR]

With the development of economy and society, various types of infrastructures have produced many high and steep slopes in Loess Plateau areas. In order to provide references for the restoration of loess steep slopes and soil erosion control, based on the results of field insitu plot observation and artificial simulated rainfall tests, the erosion control effects and mechanisms of the new organic material crosslinked polystyrene (CLPs) is the plant joint slope protection technology on the loess steep slopes were analyzed. The results show that a) the runoff depth of the loess slope treated with CLPs is larger than that of the bare slope under the same rainfall condition, and the sand production was comparable with that of the bare slope under the same rainfall conditions, there is basically no erosion-control effect of treating loess slopes only with CLPs; b) The CLPs-grass and shrub slopes and CLPs-turf slopes using CLPs-vegetation co-remediation technology, the runoff depth and soil erosion modulus were much smaller than that of traditional grass-shrub slopes and fish-scale pits planted shrub slopes, and the annual average soil erosion modulus is only 0.9%-3.2% of that of traditional grass-shrub slopes and fish-scale pits planted shrub slopes, this means that the erosion control effect of CLPs and plants on loess slopes is remarkable; e) Compared with the CLPs protection slopes without vegetation cover, the CLPs-grass and shrub joint restoration slopes with 100% vegetation coverage show a significant decrease in runoff flow rate, Reynolds number, Rroude number, shear force, and power, and a significant increase in slope resistance coefficient and roughness coefficient, which is the hydrodynamic mechanism of the CLPs-grass and shrub joint slope restoration technology for erosion control; d) Using CLPs-vegetation slope protection technology, an effective soil reinforcement system, erosion control system and water retention system can be formed on the loess steep slopes. [ABSTRACT FROM AUTHOR]

Summary All plant populations fluctuate in time. Apart from the dynamics imposed by external forces such as climate, these fluctuations can be driven by endogenous processes taking place within the community. In this study, we aimed to identify potential role of soil‐borne microbial communities in driving endogenous fluctuations of plant populations. We combined a unique, 35‐yr long abundance data of 11 common plant species from a species‐rich mountain meadow with development of their soil microbiome (pathogenic fungi, arbuscular mycorrhizal fungi and oomycetes) observed during 4 yr of experimental cultivation in monocultures. Plant species which abundance fluctuated highly in the field (particularly legumes) accumulated plant pathogens in their soil mycobiome. We also identified increasing proportion of mycoparasitic fungi under highly fluctuating legume species, which may indicate an adaptation of these species to mitigate the detrimental effects of pathogens. Our study documented that long‐term fluctuations in the abundance of plant species in grassland communities can be explained by the accumulation of plant pathogens in plant–soil microbiome. By contrast, we found little evidence of the role of mutualists in plant population fluctuations. These findings offer new insights for understanding mechanisms driving both long‐term vegetation dynamics and patterns of species coexistence and richness. [ABSTRACT FROM AUTHOR]

Understanding the complex influencing factors of soil erosion is critical for maintaining regional ecological security. The revised wind erosion equation (RWEQ) and partial least squares regression (PLSR) model were used to reveal the primary factors affecting soil erosion. Based on the results of the RWEQ model, the wind erosion area was 8,439.3 km2 in 2018, accounting for 54.3% of the total planning area, and mild erosion, moderate erosion, intense erosion, very intense erosion, and fierce erosion accounted for 18.22%, 11.43%, 11.78%, 10.16%, and 2.74% of the total planning area, respectively. Based on the results of the PLSR model, the results indicate that the proportion of mining land, meteorological indicators, and mean square deviation of slope difference were positively correlated with the soil erosion area, intensity, and severity, respectively. The proportion of grassland and forest land was negatively correlated with the soil erosion area, intensity, and severity. The mean square deviation of slope difference, the mean square deviation of difference in elevation, and the proportion of urban land use contributed the most to the soil erosion severity index, with variable importance in projection (VIP) scores of 1.55, 1.44 and 1.43, respectively. The mean square deviation of slope difference, the proportion of urban land, and the mean square deviation of difference in elevation contributed the most to the soil erosion area, with VIP scores of 1.53, 1.26 and 1.24, respectively. The results provide new insights into wind erosion and the influences of weather conditions and human influences, which can guide regional soil and water conservation planning in wind erosion regions. [ABSTRACT FROM AUTHOR]

Assisted tree migration has been proposed as a conceptual solution to mitigate lags in biotic responses to anthropogenic climate change. The rationale behind this concept is that tree species currently growing under warmer and drier climates will be more resistant and resilient to the new climatic conditions than tree species naturally growing in currently wetter and colder climates. However, we hypothesize that, by being more stress‐tolerant to warmer and drier conditions, translocated species should exhibit different functional attributes, which could induce important ecological and societal costs and overcome the desired benefits of maintaining wood production and other ecosystem services. We used principal component analysis (PCA) to analyze variation in seven traits of 106 tree and tall shrub species from contrasting latitudinal distributions in western North America and Europe to predict the potential functional changes of forest ecosystems due to the translocation of tree species from low to high latitudes. We show that species from both continents differed primarily by their position on the leaf economy spectrum (LES) and their size traits. Even though, in Europe, differences in LES were significantly correlated to species southern latitudinal positions, in both continents differences in size traits were significantly correlated to latitude. These results suggest that assisted migration by translocating more conservative species of shorter stature in currently cooler climates should decrease the buffering capacity of forest canopies, decrease facilitation for understory species, and increase wildfire risks, whose effects have the potential to accelerate climate warming through negative atmospheric feedback processes. As an alternative solution to assisted migration that may accelerate rather than mitigate climate change, we recommend that foresters gradually diversify the vertical structure and layering of the existing forest canopy to maintain a sustainable water cycle and energy balance between the soil, the tree and the atmosphere without increasing the wildfire risk. [ABSTRACT FROM AUTHOR]

Northwest China has undergone notable alterations in climate and vegetation growth in recent decades. Nevertheless, uncertainties persist concerning the response of different vegetation types to climate change and the underlying mechanisms. This study utilized the Normalized Difference Vegetation Index (NDVI) and three sets of meteorological data to investigate the interannual variations in the association between vegetation and climate (specifically precipitation and temperature) from 1982 to 2015. Several conclusions were drawn. (1) RNDVI-GP (relationship between Growing Season NDVI and precipitation) decreased significantly across all vegetation, while RNDVI-GT (relationship between Growing Season NDVI and temperature) showed an insignificant increase. (2) Trends of RNDVI-GP and RNDVI-GT exhibited great variations across various types of vegetation, with forests displaying notable downward trends in both indices. The grassland exhibited a declining trend in RNDVI-GP but an insignificant increase in RNDVI-GT, while no significant temporal changes in RNDVI-GP or RNDVI-GT were observed in the barren land. (3) The fluctuations in RNDVI-GP and RNDVI-GT closely aligned with variations in drought conditions. Specifically, in regions characterized by VPD (vapor pressure deficit) trends less than 0.02 hpa/yr, which are predominantly grasslands, a rise in SWV (soil water volume) tended to cause a reduction in RNDVI-GP but an increase in RNDVI-GT. However, a more negative trend in SWV was associated with a more negative trend in both RNDVI-GP and RNDVI-GT when the VPD trend exceeded 0.02 hPa/yr, primarily in forests. Our results underscore the variability in the relationship between climate change and vegetation across different vegetation types, as well as the role of drought in modulating these associations. [ABSTRACT FROM AUTHOR]

Biomes are large‐scale ecosystems occupying large spaces. The biome concept should theoretically facilitate scientific synthesis of global‐scale studies of the past, present, and future biosphere. However, there is neither a consensus biome map nor universally accepted definition of terrestrial biomes, making joint interpretation and comparison of biome‐related studies difficult. "Desert," "rainforest," "tundra," "grassland," or "savanna," while widely used terms in common language, have multiple definitions and no universally accepted spatial distribution. Fit‐for‐purpose classification schemes are necessary, so multiple biome‐mapping methods should for now co‐exist. In this review, we compare biome‐mapping methods, first conceptually, then quantitatively. To facilitate the description of the diversity of approaches, we group the extant diversity of past, present, and future global‐scale biome‐mapping methods into three main families that differ by the feature captured, the mapping technique, and the nature of observation used: (1) compilation biome maps from expert elicitation, (2) functional biome maps from vegetation physiognomy, and (3) simulated biome maps from vegetation modeling. We design a protocol to measure and quantify spatially the pairwise agreement between biome maps. We then illustrate the use of such a protocol with a real‐world application by investigating the potential ecological drivers of disagreement between four broadly used, modern global biome maps. In this example, we quantify that the strongest disagreement among biome maps generally occurs in landscapes altered by human activities and moderately covered by vegetation. Such disagreements are sources of bias when combining several biome classifications. When aiming to produce realistic biome maps, biases could be minimized by promoting schemes using observations rather than predictions, while simultaneously considering the effect of humans and other ecosystem engineers in the definition. Throughout this review, we provide comparison and decision tools to navigate the diversity of approaches to encourage a more effective use of the biome concept. [ABSTRACT FROM AUTHOR]

This study presents the results of a combined dendrological, macrobotanical, and dung spherulite analysis of flotation samples collected from Bronze Age, Late Assyrian, and post-Assyrian contexts at the site of Ziyaret Tepe, located on the southern bank of the Tigris River in southeastern Anatolia. The results of this study show shifting fuel resource exploitation between pre-urbanized phases of the site (ca. 3000–1600 BCE), the urbanized Late Assyrian occupation (882–611 BCE), and the ruralized post-Assyrian (ca. 611 BCE–1500 CE) re-occupations of the site. During the Late Assyrian period, Ziyaret Tepe is thought to have been the location of the city of Tušhan, an important provincial capital of the Neo-Assyrian empire. Evidence for local deforestation near the Tigris River and expanding reliance on dung fuel use during this period indicate overexploitation of fuel resources as larger populations and extractive imperial economic policies placed heavier pressure on local land use. Qualitative dendrological data provides evidence for the intensification of fuelwood harvesting during this period, while textual evidence documented an expansive program of timbering to the north of the site intended to fuel imperial construction projects in the Assyrian heartland. Following the abandonment of Tušhan and the collapse of the Neo-Assyrian empire, local fuel resource exploitation during subsequent occupations of the site shifted towards the direct management of wood fuel resources and increasing reliance on rural pastoralism. [ABSTRACT FROM AUTHOR]

Svalbards permafrost is thawing as a direct consequence of climate change. In the Low Arctic, vegetation has been shown to slow down and reduce the active layer thaw, yet it is unknown whether this also applies to High Arctic regions like Svalbard where vegetation is smaller, sparser, and thus likely less able to insulate the soil. Therefore, it remains unknown which components of High Arctic vegetation impact active layer thaw and at which temporal scale this insulation could be effective. Such knowledge is necessary to predict and understand future changes in active layer in a changing Arctic. In this study we used frost tubes placed in study grids located in Svalbard with known vegetation composition, to monitor the progression of active layer thaw and analyze the relationship between vegetation composition, vegetation structure and snow conditions, and active layer thaw early in summer. We found that moss thickness, shrub and forb height, and vascular vegetation cover delayed soil thaw immediately after snow melt. These insulating effects attenuated as thaw progressed, until no effect on thaw depth was present after 8 weeks. High Arctic mosses are expected to decline due to climate change, which could lead to a loss in insulating capacity, potentially accelerating early summer active layer thaw. This may have important repercussions for a wide range of ecosystem functions such as plant phenology and decomposition processes. Plain Language Summary: Temperatures are rising in the Arctic, causing increased thaw of the layer of soil located above the permanently frozen ground. In Low Arctic regions vegetation cools the soil, which reduces the thawing. So far, we do not know whether the small plants growing in the High Arctic may be able to slow or reduce thaw. We measured soil thaw throughout the summer in High Arctic Svalbard in locations where vegetation composition is known. We also measured thickness of the moss layer, height of plants and snow depth. We found that moss thickness was the strongest factor in insulating the soil. Also the cover of plants, height of shrubs and forbs, and height of grass‐like plants slowed soil thaw in the early summer. The insulating effects became less over time and no effects were found 8 weeks after onset of thaw. As climate change is causing changes in the Arctic vegetation, mosses and small shrubs are expected to decrease. As we found these to be the most important factors in insulating the soil, a future decrease in mosses and small shrubs may cause accelerated soil thaw at the start of summer. Key Points: High Arctic vegetation slows active layer thaw in early summer after snow meltMosses show a stronger negative relation with thaw depth than vascular vegetationFactors influencing active layer thaw change over time in early summer [ABSTRACT FROM AUTHOR]

Insects and arachnids are abundant and diverse, respond to key human impacts and support a diversity of key ecological functions. They are therefore widely recognised as effective surrogates for ecosystem condition. Their efficacy as indicators and surrogates in coastal dunes has, however, rarely been quantified, but might be instructive in guiding management in these often highly impacted coastal ecosystems. In this study, we (1) tested the effects of spatial and habitat drivers on the abundance of key insect and arachnid groups, and (2) used these patterns to identify viable management surrogates for impacts and management actions. We surveyed insect, arachnid and plant assemblages in coastal dunes at 20 sites on the Sunshine Coast in central eastern Australia. We have identified indicators for habitat condition and indicators for impact, and taxa that could be used to measure restoration outcomes. Crucially, five indicator groups also met criteria for being umbrella species, as management actions that increase their abundance would confer benefits to most other insect and arachnid taxonomic groups. We identified seven indicator groups (five insect and two arachnid), and each were affected by multiple spatial and habitat metrics, with metrics quantifying the composition and structure of vegetation communities being the most important predictors of most indicator's distributions. Implications for insect conservation: We highlight the importance of understanding subtleties in spatial patterns and the unique set of spatial and environmental conditions that each group requires when identifying suitable indicator taxa for use in the conservation and management of coastal dunes. [ABSTRACT FROM AUTHOR]

The U.S. Army Corps of Engineers, under Sect. 404 of the Clean Water Act, requires that development projects that discharge fill to Waters of the United States, including wetlands, must provide compensation through the wetland mitigation process. The Army Corps prefers that compensation is provided through purchase of credits from wetland mitigation banks, which are large wetland restoration projects constructed by third-party bank sponsors for the purpose of selling wetland mitigation credits for a profit. We assessed the regulatory outcomes of banks in the Chicago, USA, region, which possesses one of the country’s most well-developed banking markets. We used data from 22 wetland mitigation banks in the Chicago District of the Army Corps to determine how successful banks were at meeting mandatory ecological performance standards by the end of a required monitoring period. We found that banks typically struggled to meet performance standards limiting dominance by non-native species, although they often met standards related to native species richness and dominance. Perennial plant species richness and floristic quality metrics generally increased during the banks’ five-year monitoring period. The results of this study can serve as a useful resource for the continued adaptation and improvement of performance standards and mitigation assessment. [ABSTRACT FROM AUTHOR]

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An increase in precipitation due to climate change has given rise to the number of landslide occurrences. Vetiver, which is a perennial grass, is becoming increasingly popular all over the world as a vegetation-based soil bioengineering tool for preventing landslides. Sunshine Vetiver grass, also known as Chrysopogon zizanioides is noninvasive and does not compete with other indigenous plants growing in the area. Even though it is a tropical grass, Vetiver can grow in a wide range of climate conditions, including those that are quite harsh in terms of both soil and climate. The roots can grow up to 3 m in length in a dense bushy root network under optimal conditions. In this review, the authors have studied the impact of Vetiver on landslide mitigation as a climate-adaptive slope repair tool based on the research undertaken so far. Furthermore, the authors have addressed the future potential and constraints associated with the use of Vetiver for landslide mitigation. It is seen that the use of Vetiver reduces pore water pressure. The high tensile strength of Vetiver roots provides reinforcement for slopes and enhances soil shear strength. Vetiver increases saturated hydraulic conductivity and reduces surface runoff and slip surface depth. Being a vegetation-based climate-adaptive technology, this grass exhibits great promise in its ability to effectively address landslide problems. However, the magnitude of the root impact diminishes as the depth increases, rendering Vetiver a more promising remedy for shallow landslide occurrences. In addition, Vetiver grass has a wide range of practical uses due to its unique characteristics, which provide additional benefits. Employment of Vetiver is cost-effective compared with traditional engineering methods, and it requires less initial maintenance, which implies that community-based initiatives can effectively address landslide prevention through Vetiver implementation. Practical Applications: Vetiver grass has a long bushy network of roots that can grow up to 3 m in length. The Sunshine Vetiver grass is not invasive and does not compete with indigenous plants. Although Vetiver is a tropical grass, this grass can survive in various climates and soil conditions. Vetiver is a vegetation-based climate-adaptive technology that can prevent slope failure and reduce surface runoff. Additionally, growing Vetiver can generate income for local communities because the fragrant roots can be utilized in the extraction of essential oils for the perfume industry and from the manufacture and trade of other commodities derived from Vetiver. The grass's green leaves contribute to the aesthetic appeal of the landscape. Implementing Vetiver on slopes does not require heavy machinery and is cost-effective compared with traditional engineering methods. It also requires less initial maintenance, making it an ideal solution for community-based initiatives aiming to address slope failure prevention through Vetiver implementation. [ABSTRACT FROM AUTHOR]

Fire plays a key role in grasslands, determining the distribution and evolution of species and boundaries with neighboring ecosystems. Evidence of community-wide responses to fire is largely based on taxonomic and functional descriptors, while the phylogenetic dimension is overlooked. Here we evaluated how the taxonomic and phylogenetic structure of grassland plant communities responded to a time since fire (TSF) gradient. We sampled 12 communities in Southern Brazil under varying TSF and calculated taxonomic species richness (S) and dominance (D), phylogenetic diversity (PD), and mean phylogenetic distances (MPD). We used Structural Equation Models to test the relationships between the environmental gradient and community descriptors. Communities with longer TSF presented higher PD and MPD but lower species richness and increased taxonomic dominance. These sites were dominated by monocots, specifically C4 grasses, but also presented exclusive clades, whereas recently-burned sites presented lower taxonomic dominance and more species distributed in a wider variety of clades. Our results indicate that these scenarios are interchangeable and dependent on fire management. Fire adaptation was not constrained by phylogenetic relatedness, contrasting with previous findings for tropical savannahs and indicating that temperate and tropical non-forest ecosystems from South America respond differently to fire, possibly due to different evolutionary histories. [ABSTRACT FROM AUTHOR]

Globally, the increasing fire events in addition to climate change due to the emission of carbon dioxide (CO2) as well as other greenhouse gases exerts huge pressure on natural resources and their management. This phenomenon is more severe in the tropical region due to increasing population, urbanization, industrialization, existing pressures, and limiting conditions. In the present study, carbon (C) stock, carbon sequestration (Cseq), CO2 mitigation potential, C budget, and C flux of the seasonally dry forest ecosystem of Chhattisgarh under the influence of wildfire in the protected area and its proximity were evaluated. Four sites namely, high fire zone (HFZ), medium fire zone (MFZ), low fire zone (LFZ), and non‐fire zone (NFZ) were selected and marked based on fire return intervals (frequency) and extent of damage. The present work is a novel approach that assesses the impact of different fire frequencies on C dynamics of fire‐affected zones. The stratified sampling technique was used within a permanent plot of 1 hectare. Forest stands on each site were analyzed using 10 randomly placed quadrats (each 10 × 10 m in size) and data were collected from each site. Across the sites higher tree density was observed at NFZ and the lowest at HFZ.Total tree biomass ranged between 116.0 and 358.4 t ha−1 across the fire regimes. Total vegetation C stock ranged between 59.1 and 169.5 t ha−1 in different sites. The C mitigation and Cseq potential ranged between 186.2 and 575.3 t ha−1, and 7.1 and 15.9 t ha−1, respectively being highest in NFZ and lowest in HFZ. The species such as Anogeissus latifolia, Buchanania lanzan, Shorea robusta, Lannea coromandelica, Lagerstroemia parviflora, Ougeinia oojeinensis, Terminalia chebula, Terminalia tomentosa are the major contributor in biomass, C stock, C mitigation, and Cseq potential in different fire regimes. Thus, our findings would be highly useful in the restoration process of fire‐affected zones through the plantation of selective plant species. Therefore, the aforementioned species could be effectively utilized while going for an afforestation/reforestation program, and will be helpful in climate change adaptation and mitigation strategies under different fire zones. [ABSTRACT FROM AUTHOR]

Unoccupied aerial vehicle (UAV) based structure-from-motion (SfM) photogrammetry surveys are becoming a standard tool for ecologists to measure plant structure and biomass in non-forest ecosystems. The reproducibility of SfM survey results under different operational conditions, namely wind speed, sun elevation, and cloud condition, is poorly understood. It is also unclear to what extent commonly applied point-to-grid interpolation of derived point clouds affects inference of vegetation structure. These knowledge gaps limit the use of these methods for measuring and monitoring detection. We captured 61 UAV SfM surveys at the same study area under a range of wind/sun/cloud conditions over a 24-day period during 2021 and used generalized linear mixed effects models to test how the structural reconstructions varied with environmental conditions. Wind speed significantly influenced the canopy height reconstructions, with greater wind speeds reducing mean canopy height. Different plant species exhibited varying sensitivities to wind that are likely related to leaf attributes (size, structure, and density), growth form of the canopy, and physical properties such as limb flexibility. The movement of plants can reduce canopy height estimates derived from photogrammetric surveys, even under relatively low wind speeds. Reconstructed canopy heights were comparatively insensitive to solar elevation variations. Cloud conditions and illumination by direct sunlight had a weak, non-significant effect on reconstructed canopy height, with sunny conditions (generating shadows) resulting in a measurable but marginal reduction in mean canopy heights. When comparing canopy heights of interpolated and discontinuous derived canopy height models the results highlighted that these were insensitive to interpolation in this specific setting. We recommend measuring mean wind speeds throughout surveys where comparisons are to be made between different drone-based SfM surveys of vegetation over either time or space. Care should be taken to ensure that the effects of wind are controlled for so that inferences are valid. [ABSTRACT FROM AUTHOR]

The Tibetan Plateau has experienced profound climate change with significant implication for spatial vegetation greenness. However, the spatiotemporal disparities of long-term vegetation trends in response to observed climate change remain unclear. Based on remote-sensing vegetation images indicated by the normalized difference vegetation index (NDVI) from two long-term combined datasets, GIMMS and MODIS, we identified two spatiotemporal evolution patterns (SEPs) in long-term vegetation anomalies across the Tibetan Plateau. This new perspective integrates spatial and temporal NDVI changes during the growing seasons over the past four decades. Notably, the dipole evolution pattern that rotates counterclockwise from May to September accounted for 62.8% of the spatial mean amplitude of vegetation trends, dominating the spatiotemporal disparities. This dominant pattern trend is attributed to simultaneous effects of spatial warming and rising CO2, which accounted for 75% and 15%, respectively, along with a lagged effect of dipole precipitation, accounting for 6%. Overall, wetting and warming promote greening evolution in the northern Tibetan Plateau, while slight drying and warming favor browning evolution in the southern Tibetan Plateau. These findings provide insights into the combined effects of climate change on spatiotemporal vegetation trends and inform future adaptive strategies in fragile regions. [ABSTRACT FROM AUTHOR]

In 2023, most parts of the world experienced exceptional heat. In particular, anomalous warm temperatures and heatwave events were evidenced across South America during the second half of the year. The situation was particularly critical in the Amazon region in terms of not only hydrometeorological drought but also ecological and socioeconomic impacts. In this study, remote-sensing data collected from the Moderate Resolution Imaging Spectroradiometer (MODIS) were used to observe the changes in temperature and vegetation across Amazonia during the exceptional drought of 2023. This analysis was based on anomalies in the land surface temperature (LST) and vegetation indices: the enhanced vegetation index (EVI) and the normalized difference vegetation index (NDVI). The amplitude of the LST (AMP-LST), an indicator of the energy partitioning between the latent and sensible heat flux, and fire counts were also considered. The results show widespread and extreme warming across Amazonia during the austral spring in 2023, accompanied by a decline in vegetation greenness, water stress conditions across northern Amazonia, and an enhanced fire occurrence across central and northern Amazonia. [ABSTRACT FROM AUTHOR]

In river research, forecasting flow velocity accurately in vegetated channels is a significant challenge. The forecasting performance of various independent and hybrid machine learning (ML) models are thus quantified for the first time in this work. Utilizing flow velocity measurements in both natural and laboratory flume experiments, we assess the efficacy of four distinct standalone machine learning techniques—Kstar, M5P, reduced error pruning tree (REPT) and random forest (RF) models. In addition, we also test for eight types of hybrid ML algorithms trained with an Additive Regression (AR) and Bagging (BA) (AR-Kstar, AR-M5P, AR-REPT, AR-RF, BA-Kstar, BA-M5P, BA-REPT and BA-RF). Findings from a comparison of their predictive capabilities, along with a sensitivity analysis of the influencing factors, indicated: (1) Vegetation height emerged as the most sensitive parameter for determining the flow velocity; (2) all ML models displayed outperforming empirical equations; (3) nearly all ML algorithms worked optimal when the model was built using all of the input parameters. Overall, the findings showed that hybrid ML algorithms outperform regular ML algorithms and empirical equations at forecasting flow velocity. AR-M5P (R2 = 0.954, R = 0.977, NSE = 0.954, MAE = 0.042, MSE = 0.003, and PBias = 1.466) turned out to be the optimal model for forecasting of flow velocity in vegetated-rivers. [ABSTRACT FROM AUTHOR]

Due to the effects of global warming, the vapor pressure deficit (VPD) will inevitably and continuously rise in future, which is a fact that must be faced when discussing the sustainable development of vegetation ecosystems. Understanding the response of vegetation to changes in the atmospheric moisture state is necessary for minimizing the adverse effects of climate change. Using the leaf area index (LAI) and meteorological data in the Yellow River Basin collected over nearly 40 years, we explore the spatiotemporal variations in VPD and vegetation within the growing season and the differences in the effects of VPD on vegetation in different climatic zones. The results show the following: (1) both VPD and LAI in the Yellow River Basin show an increasing trend, in which VPD increases radially outward centered on the arid regions, while the vegetation develops favorably over almost the whole basin; (2) at the whole-basin scale, the area of VPD positively correlated with vegetation growth is greater than the area of negative correlation, and this overall trend is increasing significantly; (3) the VPD exerts heterogeneous effects on different vegetation in different climatic zones, and these heterogeneity findings suggest that the effects of VPD on vegetation are more influenced by differences among the climatic zones of the vegetation than by differences in the vegetation types themselves. Our results provide insights into the effects of atmospheric moisture on vegetation growth and provide references for the sustainable development of vegetation ecosystems and future safeguarding strategies of vegetation over large spatial scales. [ABSTRACT FROM AUTHOR]

Planting vegetation is a sustainable and eco-friendly method for shallow slope stabilization. However, in water-limited regions, this method is facing challenges such as retarded vegetation growth, which leads to unprotected soils. Biopolymers, with potentials in both vegetation growth promotion and soil strength enhancement, are therefore tested in this study with regard to their possibility in assisting soil reinforcement with vegetation through vegetation cultivation and direct shear tests. Both sugar-based and protein-based biopolymers improved water availability to growing plants and nutrient uptake. The most suitable polysaccharide xanthan gum was adopted to further explore the effects of treatment conditions (i.e., blending content) and external environment (i.e., precipitation) on the vegetated soil performance. Under a variety of water supplies, xanthan gum with a medium blending content of 0.5% (i.e., with respect to dry soil mass) led to the most substantial improvement in the ability to resist shear loading. This indicates that the appropriate dosage of biopolymers used at the initial stage of plant growth should provide moderate bond strength between soil particles, while not impeding root penetration. Supported by the obtained results, biopolymers are suggested to be used in combination with plants for soil reinforcement for the best efficiency. [ABSTRACT FROM AUTHOR]

The extent to which weeds in arable land are useful to pollinators depends in part on the temporal pattern of flowering and insect flight activity. We compiled citizen science data on 54 bees and hoverflies typical of agricultural areas in southern Sweden, as well as 24 flowering weed species classified as pollinator‐friendly in the sense that they provide nectar and/or pollen to pollinators. The flight periods of the bees and hoverflies varied greatly, but there were also some consistent differences between the four groups studied. The first group to fly were the early flying solitary bees (7 species), followed by the social bees (18 species). In contrast, other solitary bees (11 species) and hoverflies (22 species) flew later in the summer. Solitary bees had the shortest flight periods, while social bees and hoverflies had longer flight periods. Flowering of weed species also varied greatly between species, with weeds classified as winter annuals (e.g., germinating in autumn) starting early together with germination generalists (species that can germinate in both autumn and spring). Summer annuals (spring germinators) and perennials started flowering about a month later. Germination generalists had a much longer flowering period than the others. Weekly pollinator records were in most cases significantly explained by weed records. Apart from early flying solitary bees, all models showed strong positive relationships. The overall best explanatory variable was the total number of weeds, with a weight assigned to each species based on its potential as a nectar/pollen source. This suggests that agricultural weeds in Sweden provide a continuous potential supply of nectar and pollen throughout the flight season of most pollinators. [ABSTRACT FROM AUTHOR]

Southern African grasslands with a rich flora, shaped by fire, grazing, climate and geology, as well as playing a role in carbon sequestration, are becoming more important in conservation. Fire is often used as a management tool to improve vegetation and to protect property against uncontrolled fire. We therefore attempt to determine the effect consecutive burning has on vegetation. Paired plots along firebreaks were used to collect vegetation data using the Braun-Blanquet cover abundance scale. Soil samples were also collected to determine the impact of fire on below-ground nitrogen (N) and carbon (C) stocks and ratios. The results indicate that there is no difference between the plant communities of the firebreaks and the adjacent grassland; however, there are certain species that are favoured by firebreaks and others by the adjacent grassland. There is also no difference in diversity between the firebreaks and adjacent grassland areas. Carbon and nitrogen stocks as well as C:N ratios did not differ significantly between the firebreaks and the adjacent grassland plots although trends indicate a decline in both C and N with repeated burning. [ABSTRACT FROM AUTHOR]

The Aalenian–Bajocian (early Middle Jurassic) cooling event (ABCE) was a significant global climate disturbance during the Jurassic. Our analysis of sporopollen fossils from 18 mudstone and silty mudstone samples, collected from the lacustrine-terrestrial succession Xishanyao Formation in the Santanghu Basin, Northwest China, revealed a total of 191 species belonging to 53 genera. We identified an assemblage, the Cyathidites–Deltoidospora–Osmundacidites–Cycadopites assemblage, which dates to the Aalenian–Bajocian (early Middle Jurassic). This assemblage can be further divided into three subassemblages in stratigraphic order: the Cyathidites–Osmundacidites–Cycadopites subassemblage, the Cyathidites–Cycadopites–Psophosphaera subassemblage, and the Cyathidites–Deltoidospora–Osmundacidites subassemblage. We applied the Sporomorph EcoGroup (SEG) model to interpret the paleoclimate features. The sporopollen fossils indicate that the Santanghu Basin underwent a shift in vegetation types, from ground cover vegetation as the dominant form to canopy trees and then back to ground cover vegetation as the primary vegetation during the Aalenian–Bajocian. The SEG model analysis demonstrates that the CCP subassemblage is characterized by a low lowland SEG/upland SEG ratio, low wetter/drier ratio within the lowland SEG, and a low warmer/cooler ratio within the lowland SEG. These characteristics reflect the vegetation's response to the ABCE in the Santanghu Basin. [ABSTRACT FROM AUTHOR]

The visual characteristics of roadside landscapes affect road safety. To evaluate the influence of road landscape on safety, the focus of this study was on the landscape greening of highway roadsides based on the characteristics of secondary roads without a central divider. Using expert scoring, various indicators were statistically analysed. Then, multi-level grey correlation analysis was performed to calculate the weights of each index in an evaluation index system and establish a comprehensive evaluation model. The effects of various vegetation heights, spacings and colours on safety were quantified. Empirical analysis of three road sections of highways S319 and S246 in Hubei province, China revealed that highway safety is high when the vegetation height is 6 m, the plant spacing is 8 m and planting was coloured. The conclusions of this study provide a theoretical basis for establishing the roadside landscape along secondary roads and a preliminary theoretical reference for road design. [ABSTRACT FROM AUTHOR]

Areas that have been considered as cultural environments since ancient times have been under the influence of anthropogenic activities. That's why vegetation; It has been destroyed as a result of field clearing, grazing, fire, cutting and recently increasing mining activities. Studies carried out to reduce the impact of destruction may cause the vegetation to diversify or the presence of alien species in the field. Studies conducted in these areas, especially pollen analyses, reveal the vegetation transformation that the areas have undergone. In order to reveal the causes, results and interaction of these transformations, the results of the study were shared as a result of the research in the sample of the Gökyurt (Kilistra) ancient settlement area and its surroundings, located within the borders of Meram district of Konya province. In order to achieve the aim of the study, studies on the vegetation characteristics of the field were evaluated and the vegetation map of the field was prepared and the evaluations in the conclusion were reached. [ABSTRACT FROM AUTHOR]

Optical satellite data products (e.g., Sentinel-2, PlanetScope, Landsat) require proper validation across diverse ecosystems. This has conventionally been achieved using airborne and more recently unmanned aerial vehicle (UAV) based hyperspectral sensors which constrain operations by both their cost and complexity of use. The MicaSense Altum is an accessible multispectral sensor that integrates a radiometric thermal camera with 5 bands (475 nm–840 nm). In this work we assess the spectral reflectance accuracy of a UAV-mounted MicaSense Altum at 25, 50, 75, and 100 m AGL flight altitudes using the manufacturer provided panel-based reflectance conversion technique for atmospheric correction at the Mer Bleue peatland supersite near Ottawa, Canada. Altum derived spectral reflectance was evaluated through comparison of measurements of six known nominal reflectance calibration panels to in situ spectroradiometer and hyperspectral UAV reflectance products. We found that the Altum sensor saturates in the 475 nm band viewing the 18% reflectance panel, and for all brighter panels for the 475, 560, and 668 nm bands. The Altum was assessed against pre-classified hummock-hollow-lawn microtopographic features using band level pair-wise comparisons and common vegetation indices to investigate the sensor's viability as a validation tool of PlanetScope Dove 8 band and Sentinel-2A satellite products. We conclude that the use of the Altum needs careful consideration, and its field deployment and reflectance output does not meet the necessary cal/val requirements in the peatland site. [ABSTRACT FROM AUTHOR]

Monitoring inundation in flow-dependent floodplain wetlands is important for understanding the outcomes of environmental water deliveries that aim to inundate different floodplain wetland vegetation types. The most effective way to monitor inundation across large landscapes is with remote sensing. Spectral water indices are often used to detect water in the landscape, but there are challenges in using them to map inundation within the complex vegetated floodplain wetlands. The current method used for monitoring inundation in the large floodplain wetlands that are targets for environmental water delivery in the New South Wales portion of the Murray–Darling Basin (MDB) in eastern Australia considers the complex mixing of water with vegetation and soil, but it is a time-consuming process focused on individual wetlands. In this study, we developed the automated inundation monitoring (AIM) method to enable an efficient process to map inundation in floodplain wetlands with a focus on the lower Lachlan floodplain utilising 25 Sentinel-2 image dates spanning from 2019 to 2023. A local adaptive thresholding (ATH) approach of a suite of spectral indices combined with best available DEM and a cropping layer were integrated into the AIM method. The resulting AIM maps were validated against high-resolution drone images, and vertical and oblique aerial images. Although instances of omission and commission errors were identified in dense vegetation and narrow creek lines, the AIM method showcased high mapping accuracy with overall accuracy of 0.8 measured. The AIM method could be adapted to other MDB wetlands that would further support the inundation monitoring across the basin. [ABSTRACT FROM AUTHOR]

The most rapid climate warming is occurring in northern, permafrost environments. Peatlands of these regions are particularly sensitive to climate warming, with the high ground ice content of peat plateaux resulting in the formation of collapse scars as ground temperatures warm.To quantify the rates of permafrost thaw and associated vegetation changes, we sampled the plant and lichen communities in transects spanning actively thawing collapse scar margins at sites from mid‐Boreal to Low Subarctic conditions, within Canada's Northwest Territories. Seventeen transects were sampled in 2007/08 and 14 of these were resampled 10 years later.The rate of lateral permafrost thaw of collapse scar margins ranged from −6 to 63 cm year−1 (mean: 22.0 cm ± 4.7 cm year−1 (SE)); variability was high and no trends with respect to latitude or temperature gradients were detected.Plant communities displayed a clear gradient from lichen‐ and ericaceous shrub‐dominated peat plateaux, to collapse scars primarily characterized by Sphagnum mosses and graminoids. Both space‐for‐time (distance from collapsing margin) and direct measurement of 10‐year changes showed a successional sequence following permafrost thaw; floating mat communities characterized by Sphagnum riparium or S. balticum proceeded to lawn communities of S. angustifolium and, finally, to hummock communities with Mylia anomala or S. fuscum. This successional sequence was associated with increased water table depth and lower soil water content in plant communities farther from the actively collapsing front, illustrating that peat growth above the water table was driving plant community successional changes.The most rapid plant community succession occurred in recently thawed environments as peat growth propelled the ground surface above the water table while the slowest succession occurred in the collapse scar hummock communities located farthest from the actively collapsing peat plateau margin.Synthesis. In just 10 years, significant vegetation change was detected, in association with both permafrost thaw and subsequent plant community succession. These changes occurred across a broad climatic and latitudinal gradient, from mid‐Boreal to Low Subarctic and have implications for wildlife, global C cycle and indigenous communities who depend on this landscape for harvesting, spiritual and cultural practices. [ABSTRACT FROM AUTHOR]

Understanding fire and large herbivore interactions in interior western forests is critical, owing to the extensive and widespread co‐occurrence of these two disturbance types and multiple present and future implications for forest resilience, conservation and restoration. However, manipulative studies focused on interactions and outcomes associated with these two disturbances are rare in forested rangelands. We investigated understory vegetation response to 5‐year spring and fall prescribed fire and domestic cattle grazing exclusion in ponderosa pine stands and reported long‐term responses, almost two decades after the first entry fires. In fall burn areas open to cattle grazing, total understory cover prior to utilization was about 12% lower compared with fall burn areas where cattle were experimentally excluded. This response was not strongly driven by a particular palatable or unpalatable plant functional group. Fire and grazing are likely interacting in a numerically mediated process, as we found little evidence to support a functionally moderated pathway. Post‐fire green‐up may equalize forage to a certain extent and concentrate herbivores in the smaller burned areas within pastures, constraining a positive understory response to burning. Fall fire and grazing also increased annual forbs and resprouting shrubs. The effects of spring burning were relatively minor, and we found no interaction with grazing. The nonnative annual grass Bromus tectorum (cheatgrass) remains a problematic invader linked to fall burning but not grazing in stands that had higher propagule pressure when the experiment was initiated. At these sites, exotic grass was a major component of the vegetation by 2015, and invasion was also increasing in spring burn and unburned areas. Information from our study suggests that frequent fall fires and cattle grazing combined may reduce understory resilience in similar dry ponderosa pine forests. Consideration of longer fire return intervals, resting areas after fire, virtual fencing, or burning entire pastures may help to mitigate the effects noted in this study. [ABSTRACT FROM AUTHOR]

This study explores the importance of vegetation (display trees) in shaping the habitat preferences, mating behaviours, and survival strategies of Pteroptyx fireflies in Southeast Asia, especially Malaysia. The research highlights the crucial role of diverse plant species, tree characteristics, and specific plant components in influencing firefly behaviour, emphasising the impact of vegetation composition, structure, and function. The findings underscore the essential role of vegetation in providing resources such as food, shelter, and suitable breeding sites, thereby shaping the distribution and abundance of firefly populations in their natural habitats. Moreover, the study elucidates the significant influence of plant-related chemical compounds and emissions on firefly behaviour and ecosystem dynamics, underscoring the intricate interplay between plant life and insect populations. This comprehensive understanding of the intricate dynamics between fireflies and their vegetation landscape has substantial implications for conservation efforts and the sustainable management of their habitats. [ABSTRACT FROM AUTHOR]

Al-Fawzan Reserve in the middle of Saudi Arabia has poor floral diversity according to studies. A comprehensive assessment was carried out for the first time to analyze the floristic structure, phytogeographical distribution, life forms, and plant diversity of the observed taxa. A total of 145 taxa, belonging to 107 genera and 38 families within the Angiospermae, were successfully recognized. Asteraceae was the plant family that constitutes most of the study area's vegetation (25 species), followed by Brassicaceae (16 species), Fabaceae (14 species), Amaranthaceae (12 species), Poaceae (9 species), Zygophyllaceae (7 species), and Plantaginaceae (5 species, 3.4%), meanwhile, the remaining families were each characterized by the presence of one, two, three, or four species. Chamaephytes demonstrated the highest proportion of species (39.3%), followed by Therophytes (35.2%), Hemicryptophytes (11%), Geophytes and phanerophytes (6.9% each), with Parasites being the least prevalent life form group (0.7%). The floristic data of the chorological analysis revealed that the Bi-regional category is the most dominant chorotype in the study area (46.2%), followed by Mono-regional, Pluri-regional, and Worldwide (37.2%, 12.4%, 4.1%, respectively). Data from the current study exhibited that the majority of total recorded taxa (78 species) are perennials, while annuals life spans was counted for (67 species). The current study concluded that 61 species are rare. Out of them, 13 species are classified as least concern (LC) according to the IUCN dataset. The current investigation holds potential value for the effective management and conservation of the studied geographical area. [ABSTRACT FROM AUTHOR]

Desert wadis serve as essential ecosystems for socioeconomic development because of their biological value, physiographic heterogeneity, and environmental gradients. The study aims to evaluate Wadi Murr, the largest wadi ecosystem in Makkah, as a plant diversity hotspot regarding floristic diversity and vegetation along the prevailing environmental gradients. Data were collected from 102 stands across 17 sampling sites, representing the vegetation physiognomy along the wadi. About 118 species related to 81 genera and 35 families have been recognized, the Poaceae family notably prevailing in dominance. Therophytes prevailed among other life forms, and biregional taxa exhibited dominance among other chorotypes. The Two-way indicator species analysis (TWINSPAN) revealed 13 distinct vegetation groups (VGs) segregation along the two Detrended Correspondence Analysis (DECORANA) axes. Seven VGs (D, F, H, I, K, L, M) were dominated by halophytic species of family Zygophyllaceae, while VG (A) was dominated by the rocky community Capparis decidua, and VG (B and G) was dominated by the tree's communities Vachellia seyal and Senna italica. Besides, VG (E) is dominated by a grass community (Aristida pennei), and VG (J) is dominated by the medicinal herb Citrullus colocynthis. The Principal Component Analysis (PCA) ordination explained that Cl-, SO4 2-, pH, EC, fine sand, silt, and gravel significantly influenced the plant communities. Furthermore, certain plant communities, such as Capparis decidua and Senna italica exhibited positive responses to the following soil variables: Ca2+, Mg2+, and Na+. In contrast, others, such as Tribulus pentandrus were negatively affected by gravels, coarse sand, and fine sand. The species richness ranged from 1.3 species stand-1 in Capparis decidua-Cenchrus divisus group (VG A) to 13.1 species stand-1 in Senna italica-Stipagrostis hirtigluma (VG: G). The limited species diversity observed in certain plant communities implies the eradication of the original vegetation, emphasizing the pressing need for habitat rehabilitation. [ABSTRACT FROM AUTHOR]

Background When cardiac implantable electronic device infection occurs, standard therapy is usually total system extraction. Transvenous lead extraction is preferable to open heart surgical extraction, unless contraindicated because of the presence of very large vegetations on the intravenous leads according to the European Society of Cardiology guidelines. Extraction of transvenous leads with vegetations risks distal embolism resulting in obstruction and/or infection in the pulmonary arteries. Catheter aspiration of vegetations or thrombi has been performed prior to transvenous lead extraction using a partial veno-venous extracorporeal bypass circuit. We report the use of a single-access aspiration system using the Inari FlowTriever 24 French system to debulk a defibrillator lead before percutaneous extraction. Case summary A 79-year-old male presented with fever 18 years after his first implantable cardioverter defibrillator implant and 9 years after his most recent pulse generator change. Two large vegetations were identified on his transvenous defibrillator lead on the atrial aspect, near the tricuspid annulus, which were aspirated using the Inari Medical 24Fr FlowTriever aspiration catheter. We describe anatomical considerations during the approach and a technique to localize the vegetations based on a combination of fluoroscopy and transoesophageal echocardiogram guidance. Discussion This case demonstrates the safe and effective use of the Inari Medical 24Fr FlowTriever aspiration catheter in debulking a defibrillator lead before transvenous lead extraction. This method uses a single venous puncture and is not dependent on extracorporeal bypass. Apart from reducing complexity, this technique may be advantageous in patients where anticoagulation needs to be minimised. [ABSTRACT FROM AUTHOR]

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As a plant kingdom and a biodiversity hotspot, Yunnan is a key region for our understanding of modern and past global changes in biodiversity and environment. As proxies of vegetation and climate, phytoliths have become increasingly important in ecological and paleoecological studies. In this study, phytolith analysis was carried out on samples of surface sediments from 70 lakes in western Yunnan, southwest China. These lakes are surrounded by modern vegetation types including broadleaved and coniferous forests, scrubs, grasslands, meadows, and alpine vegetation. The results of this study show that modern lacustrine phytoliths in western Yunnan are dominated by herbaceous phytoliths, among which Poaceae types are the most abundant. The 70 phytolith samples used can be divided into 4 groups, reflecting the major vegetation types from which samples were collected. The principal component analysis (PCA) and redundancy analysis (RDA) of the phytolith and climatic data of the 70 lacustrine phytolith samples showed that temperature and precipitation are the climatic parameters controlling the spatial distribution of phytolith assemblages in western Yunnan. Phytolith–MAT (mean annual temperature) and phytolith–MAP (mean annual precipitation) transfer functions were developed using weighted averaging partial least squares (WA-PLS), and both the MAT and MAP functions showed good performances (MAT: R2 = 0.67, RMSEP = 0.96 °C, MAP: R2 = 0.64, RMSEP = 140.4 mm). Our results also reveal that phytolith analysis is a useful technique offering reliable vegetation interpretation and climate reconstruction; thus, this study provides a basis for the vegetational and climatic interpretation of fossil lacustrine phytolith records in western Yunnan. [ABSTRACT FROM AUTHOR]

Native valve infective endocarditis (NVE) is a global phenomenon, defined by infection of a native heart valve and involving the endocardial surface. The causes and epidemiology of the disease have evolved in recent decades, with a doubling of the average patient age. A higher incidence was observed in patients with implanted cardiac devices that can result in right-sided infection of the tricuspid valve. The microbiology of the disease has also changed. Previously, staphylococci, which are most often associated with health-care contact and invasive procedures, were the most common cause of the disease. This has now been superseded by streptococci. While innovative diagnostic and therapeutic strategies have emerged, mortality rates have not improved and remain at 30%, which is higher than that for many cancer diagnoses. The lack of randomized trials and logistical constraints impede clinical management, and long-standing controversies such as the use of antibiotic prophylaxis persist. This state of the art review addresses clinical practice, controversies, and strategies to combat this potentially devastating disease. A multidisciplinary team will be established to provide care for patients with presumptive NVE. The composition of the team will include specialists in cardiology, cardiovascular surgery, and infectious disease. The prompt administration of combination antimicrobial therapy is essential for effective NVE treatment. Additionally, a meticulous evaluation of each patient is necessary in order to identify any indications for immediate valve surgery. With the intention of promoting a more comprehensive understanding of the procedural management of native infective endocarditis and to furnish clinicians with a reference, the current evidence for the utilization of distinct strategies for the diagnosis and treatment of NVE are presented. [ABSTRACT FROM AUTHOR]

Snow, especially in mountainous regions, plays a major role acting as a quasi-reservoir, as it gradually releases fresh water during the melting season and thereby fills rivers, lakes, and groundwater aquifers. For vegetation and irrigation, the timing of the snowmelt is crucial. Therefore, it is necessary to understand how snowmelt varies under different local conditions. While differences in slope aspect and vegetation (individually) were linked to differences in snow accumulation and ablation, this study connects the two and describes their influence on the soil moisture response to snowmelt. This research focuses on the catchment of the "Brunnenkopfhütte" (BKH) in Bavaria, southern Germany, where an automatic weather station (AWS) has operated since 2016. In addition, soil temperature and moisture monitoring systems in the surrounding area on a south aspect slope on an open field (SO), on a south aspect slope in the forest (SF), and a north aspect slope in the forest (NF) have operated since 2020. On snow-free days in winter, the soil temperature at the SF site was on average 1 °C lower than on the open site. At the NF site, this soil temperature difference increased to 2.3 °C. At the same time, for a 1 °C increase in the air temperature, the soil temperature increases by 0.35 °C at the NF site. In addition, at this site, snow cover disappeared approximately one week later than on the south aspect slopes. Snow cover at the SF site disappeared even earlier than at the SO site. Finally, a significant difference in the soil moisture response was found between the sites. While the vegetation cover dampens the magnitude of the soil moisture increases, at the NF site, no sharp increases in soil moisture were observed. [ABSTRACT FROM AUTHOR]

A phytosociological analysis of the plant communities in high-altitude volcanic caves of Mount Etna (Sicily), based on literature data and unpublished relevés, is presented. A total of 147 phytosociological relevés were processed and analyzed using classification and ordination methods. Classification of the relevés, supported by ordination, showed two main vegetation groups: the first one includes communities of the Pohlion crudae alliance, and the other includes the vegetation from the Pohlio crudae–Asplenion septentrionalis alliance. Furthermore, two new communities, Pohlio crudae–Cystopteridetum dickieanae subass. amphidietosum mougeotii and Pohlio crudae–Cystopteridetum dickieanae subass. polystichetosum lonchitis, are proposed for Etna. The high-altitude caves can be considered a refuge for these ptero-bryophytic rare communities. [ABSTRACT FROM AUTHOR]

Climate change is one of the main factors that caused scarcity of fresh water phenomenon all over the world. The lack of water in major parts of Iraq affected all sectors that use water and cause obvious damages to ecosystems. Karbala province suffers from frequent water scarcity due to water scarcity and abnormally high temperatures. In the present study, remote sensing and GIS were applied to quantify water scarcity and evaluate its effects on vegetation in this fragile semiarid ecosystem. Analysis of hydrological data of the study area was carried out during 2013 to 2022 to compute water availability and shortage based on the criteria and requirements of water sector and environmental management in Iraq. Remotely sensed Landsat 8 images data were applied to measure changes on vegetation and the effects of water scarcity. Soil Adjusted Vegetation Index (SAVI) was employed to identify vegetation and detect its change. Results showed that the area witnessed decreasing in water availability compared to the reference year. Maximum available water reached 1977.535 million m 3 in 2013, while the minimum of 859.227 million m 3 was observed in 2022. The maximum and minimum vegetation area reached 535.610 km 2 and 430.605 km 2 in 2013 and 2022, respectively. Results indicated that all the years posterior to the reference year experienced water scarcity and vegetation damage, where the maximum and minimum water scarcity rates were 56% and 8% in 2022 and 2016, respectively. The maximum impact of water scarcity rate on vegetation was ca. 20% in both years 2015 and 2022. Water scarcity is constantly increasing over time, thus evaluating its impacts and forecasting its future specification will support decision-makers to take the necessary measures to mitigate its effects. [ABSTRACT FROM AUTHOR]

The framework proposed in this article has investigated the effects of physical and vegetational features of tall building scapes on restoration likelihood. This framework focuses on the form of window openings and gaps in the building and, in the case of vegetation of tall building scapes, studies the amount and type of vegetation. Physical and vegetational variables were manipulated in simulation environments to obtain 120 color images. 54 participants in 6 groups evaluated these images based on restoration likelihood, fascination, being away, preference, perceived complexity, and perceived enclosure. Results indicated a more significant role of physical variables than vegetation in restoration likelihood. Moreover, increasing openings and gaps in the physics of a tall building has reduced restoration; however, they had no indirect effect on restoration through mediator variables of fascination and being away. Increasing vegetation and using more bulky vegetation (from flowers to trees and green walls) have shown positive effects on restoration and indirectly affected it through the mediator variable of being away. Moreover, analyzing different categories of physical and vegetational variables of tall building scapes showed that horizontal opening, absence of gap, increasing horizontal vegetation, and using more bulky vegetation significantly impact restoration (positively). [ABSTRACT FROM AUTHOR]

Copyright of Geography & Environmental Sustainability is the property of Razi University 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.)

Recent environmental issues, rising water demand, and the decreasing supply of natural water resources require the provision of additional quantities of water to ensure the sustainability of ecosystems and water resources. In this study, a systematic approach was used to choose suitable sites for rainwater harvesting (RWH) using an analytic hierarchy process-based multi-criteria evaluation approach in Wadi Sarkhar, Iraq. In order to produce the suitability map, seven criteria layers were used: precipitation, slope, elevation, drainage density, Normalized Difference Vegetation Index (NDVI) obtained from Sentinel 2 data, type of soil, and soil moisture. The area of study has a considerable topographical disparity in altitudes that was ranging from 10 to 2000 m. Special attention was paid to this fact, so the performance of a slope analysis was necessary to identify the sites for RWH appropriately. After analyses of the slope and drainage density layer, new insight about the hydrologic capacity and characteristics was obtained. Long-term precipitation records were essential for determining the sustainability of RWH especially in semi-arid regions. Moreover, the NDVI layer data were used to detect land cover and vegetation distribution. Soil type and soil moisture were utilized to evaluate the ground capacity to retain water. The study area was classified by the final suitability map into three different zones: low suitability, unsuitable zone, and high suitability. This study outcome will provide a systematic approach to the selection of suitable places for RWH, ensure competent management of water resources, and provide an idea about ecosystems and water resources sustainability. [ABSTRACT FROM AUTHOR]

This study analyzes the impact of containment due to the COVID-19 pandemic on the vegetation cover of the Korifla sub-watershed, based on remote sensing data and spatial analysis. The aim of this study was to analyze the impact of the containment imposed in response to the COVID-19 pandemic on the vegetation cover and to highlight significant changes in the distribution of normalized difference vegetation index (NDVI) before and after the containment period, as well as to identify the areas most affected by these changes. The results highlight significant fluctuations in the distribution of vegetation cover, including a decrease in water area and variations in the categories of bare soil, sparse, medium-dense and dense vegetation. Using NDVI as an indicator of vegetation health, changes before and after the confinement period were highlighted. These results highlight the impact of anthropogenic disturbances such as confinement on plant ecosystems, and underline the importance of continuously monitoring vegetation cover for sustainable natural resource management and biodiversity preservation. With climatic conditions in Morocco stagnating in the two years following containment, the climatic factor is now set aside, and the focus shifts to the impact of reduced human activity. [ABSTRACT FROM AUTHOR]

Green vegetation may protect against heat-related death by improving thermal comfort. Few studies have investigated associations of green vegetation with heat-related mortality in Latin America or whether associations are modified by the spatial configuration of green vegetation. We used data from 323 Latin American cities and meta-regression models to estimate associations between city-level greenness, quantified using population-weighted normalized difference vegetation index values and modeled as three-level categorical terms, and excess deaths from heat (heat excess death fractions [heat EDFs]). Models were adjusted for city-level fine particulate matter concentration (PM2.5), social environment, and country group. In addition to estimating overall associations, we derived estimates of association stratified by green space clustering by including an interaction term between a green space clustering measure (dichotomized at the median of the distribution) and the three-level greenness variable. We stratified analyses by climate zone (arid vs. temperate and tropical combined). Among the 79 arid climate zone cities, those with moderate and high greenness levels had modestly lower heat EDFs compared to cities with the lowest greenness, although protective associations were more substantial in cities with moderate versus high greenness levels and confidence intervals (CI) crossed the null (Beta: -0.41, 95% CI: -1.06, 0.25; Beta -0.23, 95% CI: -0.95, 0.49, respectively). In 244 non-arid climate zone cities, associations were approximately null. We did not observe evidence of effect modification by green space clustering. Our results suggest that greenness may offer modest protection against heat-related mortality in arid climate zone Latin American cities.