Search

Background: Community species in different grassland types exhibit unique ecological traits and adaptation strategies, influencing the impact of grazing on species diversity at various scales. This study aimed to elucidate the response characteristics and rules of species diversity in different grassland types to grazing intensity by analyzing plant groups and species diversity. Results: Grazing intensity, grassland type, and their interaction significantly affected α, β, and γ diversity. In meadow steppes, α and γ diversity conformed to the intermediate disturbance hypothesis, exhibiting a unimodal trend with increasing grazing intensity—initially increasing and then decreasing. In typical steppes, α, β and γ diversity showed no clear pattern in response to changes in grazing intensity. In desert steppes, α, β and γ diversity consistently declined with increasing grazing intensity. In meadow steppes, dominant and common species were crucial for sustaining community (α diversity) and landscape (γ diversity) diversity, whereas rare species primarily contributed to increased gradient differences (β diversity). In typical steppes, rare species were pivotal for community (α diversity) and landscape (γ diversity) diversity, while dominant and common species were important in reducing gradient differences (β diversity). In desert steppes, rare species were vital for maintaining community diversity (α diversity), dominant species played a key role in reducing gradient differences (β diversity), and common species were important for maintaining landscape-level diversity (γ diversity). Conclusions: The characteristics and patterns of grazing intensity on species diversity at different scales, as well as the dominant plant group influencing plant species diversity at different scales, are controlled by grassland types. These findings highlight the need for tailored management strategies to conserve species diversity in various grassland ecosystems under different grazing pressures. [ABSTRACT FROM AUTHOR]

Plant species diversity may be considerably underestimated, especially in evolutionarily complex genera and in diversity hotspots that have enabled long‐term species persistence and diversification, such as the Balkan Peninsula. Here, we address the topic of underexplored plant diversity and underlying evolutionary and biogeographic processes by investigating the hygrophytic mountain species complex of Cardamine acris s.l. distributed in the Balkans (three subspecies within C. acris) and northwestern Anatolia (C. anatolica). We performed a series of phylogenetic and phylogeographic analyses based on restriction‐site associated DNA sequencing (RADseq) and target enrichment (Hyb‐Seq) data in combination with habitat suitability modelling. We found C. anatolica as a clade nested within the Balkan C. acris, probably resulting from a founder event, and uncovered three allopatric cryptic lineages within C. acris subsp. acris, allowing us to recognise a total of six entities in this complex. We observed the deepest genetic split within C. acris subsp. acris in the western Balkans, which was at odds with taxonomy and showed no distribution gap. We inferred vicariance as the most likely process for population divergence in the Balkans, accompanied by gene flow between the recognised entities, which was consistent with the modelled habitat suitability dynamics. Furthermore, we discovered several polyploid populations in C. acris, representing both pure intra‐ and inter‐lineage hybrid polyploids, but detected only minor traces of hybridization with related congeners. Overall, our results illustrate that diverse evolutionary processes may influence the history of mountain plant species in the Balkan Peninsula, including vicariance, reticulation, polyploidization and cryptic diversification. [ABSTRACT FROM AUTHOR]

Cotton (Gossypium spp.) is a vital global source of renewable fiber and ranks among the world's most important cash crops. While extensive nuclear genomic data of Gossypium has been explored, the organellar genomic resources of allotetraploid cotton, remain largely untapped at the population level. The plastid genome (plastome) is well suited for studying plant species relationships and diversity due to its nonrecombinant uniparental inheritance. Here, we conducted de novo assembly of 336 Gossypium plastomes, mainly from domesticated cultivars, and generated a pan‐plastome level resource for population structure and genetic diversity analyses. The assembled plastomes exhibited a typical quadripartite structure and varied in length from 160 103 to 160 597 bp. At the species level, seven allotetraploid species were resolved into three clades, where Gossypium tomentosum and Gossypium mustelinum formed an early diverging clade rooted by diploids, followed by splitting two sister clades of Gossypium darwinii–Gossypium barbadense and Gossypium hirsutum–Gossypium ekmanianum–Gossypium stephensii. Within the G. hirsutum clade the resolution of cultivated accessions was less polyphyletic with landrace and wild accessions than in G. barbadense suggesting some selection on plastome in the domestication of this adaptable species of cotton. The nucleotide diversity of G. hirsutum was higher than that of G. barbadense. We specifically compared the plastomes of G. hirsutum and G. barbadense to find mutational hotspots within each species as potential molecular markers. These findings contribute a valuable resource for exploring cotton evolution as well as in the breeding of new cotton cultivars and the preservation of wild and cultivated germplasm. [ABSTRACT FROM AUTHOR]

Extreme drought and intensification of land use pose substantial threats to ecosystem stability. However, existing studies that assess ecosystem stability focus primarily on the stability of aboveground net primary productivity (ANPP), while the stability of belowground net primary productivity (BNPP) is often not considered.Here, we examined the response patterns and drivers of ANPP stability and BNPP stability in an alpine meadow to drought and clipping (simulating grazing and mowing) by the implementation of five levels of simulated precipitation (1/12, 1/4, 1/2, 3/4 and ambient precipitation) and clipping (unclipped vs. clipped) treatments over 7 years (2016–2022).The results showed that extreme drought decreased ANPP stability, while moderate drought increased BNPP stability and net primary productivity stability. The findings highlight the importance of jointly considering above‐ and belowground processes when evaluating ecosystem stability. Moreover, clipping did not have an impact on ANPP stability but reduced BNPP stability, and clipping differentially affected the stability of ANPP and BNPP in response to extreme drought. Furthermore, ANPP stability was largely determined by species temporal asynchrony rather than richness, whereas dominant species stability strongly contributed to the variation in BNPP stability of this alpine meadow faced with drought and clipping.Synthesis: In general, these results provide experimental evidence for the decoupling of the responses of above‐ and belowground productivity stability to extreme drought and clipping. Our findings indicate that aboveground responses should not be used as the sole indicator of the whole ecosystem consequences of extreme drought and disturbance factors such as grazing or mowing, emphasizing the need to evaluate ecosystem stability from a whole ecosystem perspective. [ABSTRACT FROM AUTHOR]

Picea purpurea forests are a fundamental part of the coniferous forests of the Qinghai–Tibet Plateau. These forests support an extremely rich diversity of organisms while providing crucial ecological functions. Despite their importance, the species and phylogenetic diversity (PD) of these forests remain understudied. The extent to which different plant growth forms in the forest are influenced by the environment varies according to differences in the evolutionary history and characteristics of these taxa. Here, we investigate the variations in all, woody, and herbaceous plant species diversity (SD) and PD in the eastern Qinghai–Tibet Plateau's Picea purpurea forests, along with the associated environmental factors influencing these patterns. Our results show that both SD and PD exhibit similar patterns across all, woody, and herbaceous plants. Notably, mean annual precipitation, total nitrogen, and altitude were identified as the primary factors accounting for the majority of variance in SD and PD within plant communities. Specifically, we found positive correlations between SD and PD with soil total nitrogen content, while negative correlations were observed with mean annual precipitation and altitude. Furthermore, we find that the influence of environmental variables on all plants was found to be more pronounced compared to woody and especially herbaceous plants in terms of both SD and PD. Environmental factors had a direct effect on SD and PD in all woody and herbaceous plants. However, the strength of these effects varied. Importantly, our results indicate that environmental factors influence SD independently of PD. Our findings suggest that precipitation and total soil nitrogen were the most influential environmental factors affecting plant diversity across different growth forms in Picea purpurea communities. However, inferring SD from PD remains a challenging task. These findings of our study will provide guidance for forest biodiversity conservation and sustainable forest management in the Qinghai–Tibet Plateau. [ABSTRACT FROM AUTHOR]

Road salt poses a threat to the quality of soils and water resources. Wetlands located in salt contaminated areas are at risk of experiencing lower plant and animal species diversity. Therefore, it is critical to understand how modifications to salt application rates and hydrological events impact wetland water quality. Here, we use chloride mass flux, discharge, groundwater chloride concentration, meteorological, and salt application data from 2012–2020 to estimate chloride accumulation and outflux rates in the Kampoosa Bog subwatersheds, located in Stockbridge and Lee, Massachusetts, and bordered by major highways (Interstate-90 and U.S. Route 7). We also investigate the correlation between wetland size and chloride retention rate. During the 2018–2019 period, mean annual chloride application rates in the major watershed increased from 363000 kg/year (2012–2017) to 479000 kg/year. This led to a net chloride accumulation (KB100 subwatershed: 339000 kg; KB150 subwatershed: 188000 kg) and increased groundwater chloride concentrations in the fen. Chloride outflux from these subwatersheds was primarily driven by discharge. We found that the relationship between wetland percent cover and chloride retention is complex. Although the percent wetland cover is greater in the KB100 main wetland region compared to the KB150 subwatershed, high precipitation in 2018 resulted in similar chloride retention efficiencies (~26%). During the drier year (2019), chloride retention was higher in the wetland region due to its gentle slopes which promote water accumulation and consequently higher evaporation rates which lowers discharge and chloride outfluxes. The chloride steady-state concentration analysis also suggests that there is potential for chloride accumulation to continue because the watershed has not yet reached steady-state chloride concentrations. Without major modifications to salting practices, chloride concentrations will continue increasing and potentially promote the re-growth of invasives (Phragmites) and continued growth of salt tolerant species (Typha angustifolia/xglauca) that diminish plant diversity. [ABSTRACT FROM AUTHOR]

While the link between plant species diversity and biomass has been well‐studied, the impact of evolutionary diversity on community biomass across long timescales or ongoing change remains a subject of debate. We elucidated the association between evolutionary diversity and community aboveground biomass (AGB) using an ideal experimental system with over 150‐year history of natural vegetation regeneration. Higher phylogenetic diversity facilitated the sampling effect under the influence of environmental filtering, and caused an increase in AGB. Phylogenetic structure varied from aggregation to dispersion during the later period of vegetation recovery (70–150 years), which was correlated with increases in niche complementarity and increasing AGB. Woody plant evolutionary diversity was used as a key to predict the relationship between vegetation recovery and AGB, with a total explanatory power of ~84.7%. Mixed forests composed of evergreen conifers and deciduous broadleaf forests had higher carbon sequestration potential than that of pure forests, which is advantageous for increasing top‐stage AGB. This research expands our knowledge of the causes and effects of biodiversity and ecosystem function dynamics over time and space, which is important for accurately predicting future climate change effects. [ABSTRACT FROM AUTHOR]

Given that terrestrial ecosystems globally are facing the loss of biodiversity from land use conversion, invasive species, and climate change, effective management requires a better understanding of the drivers and correlates of biodiversity. Increasingly, biodiversity is co‐managed with aboveground carbon storage because high biodiversity in animal species is observed to correlate with high aboveground carbon storage. Most previous investigations into the relationship of biodiversity and carbon co‐management do not focus on the biodiversity of the species rich plant kingdom, which may have tradeoffs with carbon storage. To examine the relationships of plant species richness with aboveground tree biomass carbon storage, we used a series of generalized linear models with understory plant species richness and diversity data from the USDA Forest Service Forest Inventory and Analysis dataset and high‐resolution modeled carbon maps for the Tongass National Forest. Functional trait data from the TRY database was used to understand the potential mechanisms that drive the response of understory plants. Understory species richness and community weighted mean leaf dry matter content decreased along an increasing gradient of tree biomass carbon storage, but understory diversity, community weighted mean specific leaf area, and plant height at maturity did not. Leaf dry matter content had little variance at the community level. The decline of understory plant species richness but not diversity to increases in aboveground biomass carbon storage suggests that rare species are excluded in aboveground biomass carbon dense areas. These decreases in understory species richness reflect a tradeoff between the understory plant community and aboveground carbon storage. The mechanisms that are associated with observed plant communities along a gradient of biomass carbon storage in this forest suggest that slower‐growing plant strategies are less effective in the presence of high biomass carbon dense trees in the overstory. [ABSTRACT FROM AUTHOR]

• Vegetation classification improve our knowledge and understanding of complex ecosystems. • Vegetation classification, description and mapping method for large areas (> 90 000 hectares). • The use of Sentinel-2 and topo-morphological data in conjunction with limited floristic surveys (new approach) resulted in an accurate classification, description and vegetation map of the Karoo National Park. • A total of 12 major plant communities and two sub-communities that are distinctly linked to various abiotic factors were identified, described and mapped for the Karoo National Park. The higher-lying rocky steep midslopes as well as the valley bottomland areas had the highest diversity and species richness. This study aimed at classifying, mapping and describing the plant communities of the Karoo National Park using floristic surveys in conjunction with Sentinel-2 and topo-morphological data. Karoo National Park, Western Cape, South Africa. The vegetation of the Karoo National Park was delineated into homogenous physiognomic-physiographic units using Sentinel-2 images. A total of 128 survey plots (100 m2 each) were surveyed within the different homogeneous units during the period 2016 to 2020. Within each survey plot, all rooted species were identified and their cover abundance estimated. Each plot was photographed and its geolocation recorded. The floristic data were captured using the Braun Blanquet Personal Computer suite and exported to the JUICE Software programme. A modified TWINSPAN classification was done to derive a first tabled synopsis of the plant communities. The different plant communities were subsequently classified and described according to their diagnostic and dominant species gleaned from the synoptic table. Species richness was determined by counting the number of different species per plant community while the Shannon–Wiener Index and Rich-Gini–Simpson Index of diversity (D) were used to derive indices of species diversity per plant community. 12 major communities and two sub-communities that are distinctly linked to various abiotic factors were identified, described and mapped. The higher-lying rocky steep midslopes as well as the valley bottomland areas had the highest diversity and species richness. This study proves the efficacy of using Sentinel-2 and topo-morphological data in classification, description and mapping vegetation of extensive natural areas. The vegetation map and classification of plant communities provide a baseline to inform management decisions. Taxonomic reference: SA-Plant Checklist-2019–2020, South African National Biodiversity Institute, 2020, Botanical Database of Southern Africa (BODATSA) (http://posa.sanbi.org/) [accessed January 2022]. [ABSTRACT FROM AUTHOR]

• Nassella trichotoma is a serious invasive grass in South Africa's Mountain grasslands. • N. trichotoma alters soil nutrients, which impacts reestablishment of native plant species. • N. trichotoma invasion is associated with lower native and higher non-native species richness. • Native plant diversity is reduced by N. trichotoma invasion. Nassella trichotoma (Poaceae) is a highly invasive South American grass that is invading montane grasslands in the Eastern and Western Cape provinces of South Africa. Although N. trichotoma has been recognised as a major problem in these mountains for decades, the primary concern has been on impacts on rangeland productivity and management, while the impacts of invasions on plant biodiversity have not been considered. To understand the impact of N. trichotoma on local plant biodiversity, 81 pairs of plots (total of 162 plots) were laid out in the Sneeuberg and Eastern Cape Drakensberg mountains, Eastern Cape, in March 2020 and March 2021. At each site plots were located in grassland invaded by N. trichotoma and in nearby uninvaded grassland (control). A total of 20 N. trichotoma patches were sampled with two to four plot pairs per site. All vascular plant species were recorded in all plots, the cover abundance of each species per plot was visually estimated, and the topsoil was sampled and analysed for differences in nutrient and physical factors between invaded and uninvaded plots. Plant species diversity was 24 % higher in uninvaded areas, and the native grasses Pentameris airoides (Χ2 = 4.93, d.f. = 1, p < 0.01), Tenaxia disticha (Χ2 = 5.51, d.f. = 1, p < 0.01), and Themeda triandra (Χ2 = 9.28, d.f. = 1, p < 0.001) were significantly less abundant in invaded plots. Uninvaded areas had greater native species diversity (65 species) and fewer alien species (3) than invaded areas (47 and 9 respectively). Of the 18 soil variables measured, the following were significantly higher in invaded areas than uninvaded areas: boron (23 %), calcium (18 %), phosphorous (58 %), silt (10 %), total cations (12 %), and zinc (68 %). This suggest that N. trichotoma alters soil nutrients. The results indicate that N. trichotoma is a powerful driver of native biodiversity erosion in these montane grasslands and should be a cause for major concern by landowners and government. [ABSTRACT FROM AUTHOR]

Plant species diversity is key to ecosystem functioning, but in recent decades anthropogenic activities have prompted an alarming decline in this community trait. Thus, developing strategies to understand diversity dynamics based on affordable and efficient remote sensing monitoring is essential, as well as examining the relevance of spatial scale and vegetation structural complexity to these dynamics. Here, we used two mathematical approaches to assess the relationship between tropical woody species diversity and spectral diversity in a human-modified landscape in two vegetation types differing in their degree of complexity. Vegetation complexity was measured through the fraction of species that concentrate different proportions of the cumulative importance value index. Species diversity was assessed using Hill numbers at three spatial scales, and metrics of spectral heterogeneity, vegetation indices, as well as raw data from Landsat 9 and Sentinel-2 sensors were calculated and analysed through general linear models (GLM) and Random Forest. Vegetation complexity emerged as an important variable in modelling species from remote sensing metrics, indicating the need to model species diversity by vegetation type rather than region. Hill numbers showed different relationships with remotely sensed metrics, in consistency with the scale-dependency of ecological processes on species diversity. Contrary to multiple previous reports, in our study, GLMs produced the best fits between Hill numbers of all orders and remotely sensed metrics. If we are to meet the need of conducting efficient and speedy woody species diversity monitoring globally, we propose modelling this diversity from remotely-sensed variables as an attractive strategy, so long as the intrinsic properties of each vegetation type are acknowledged to avoid under- or overestimation biases. [ABSTRACT FROM AUTHOR]

BACKGROUND AND OBJECTIVES: Efforts to enhance carbon stocks and boost carbon absorption potential are essential for climate change mitigation. Peatland ecosystems, known for their high organic content, are particularly vulnerable to environmental management. The study aimed to examine the alterations in land use and land cover that occurred between 1998 and 2022, spanning a 24-year duration. Additionally, it sought to assess the associated variations in carbon stocks within the designated Kepau Jaya specific purpose forest area. The area under investigation encompasses a peatland ecosystem that has experienced substantial changes in land cover and land use. This study investigated the fluctuations in carbon stock caused by these alterations and provides valuable perspectives on the potential of agroforestry systems to promote a wider range of land uses. Additionally, it highlights their role in ecosystem restoration initiatives and the better management of forest peatland regions. METHODS: A spatial analysis was conducted on Landsat 5 and 8 satellite images by using shapefile data stored within the Google Earth Engine platform. Data analysis was carried out using Classification and Regression Tree, a decision tree algorithm used in machine learning for guided classification. Furthermore, purposive sampling was utilized to gather socioeconomic data, followed by the implementation of a benefit-cost analysis. FINDINGS: The results revealed significant changes in the land cover within the Kepau Jaya specific purpose forest area over a 24-year period, with forested areas and open areas decreasing by 23.15 hectares per year and 16.94 hectares per year respectively, and oil palm plantation areas expanding by 40.10 hectares per year. From 1998 to 2022, there has been a consistent annual decline in carbon stocks, resulting in a reduction of 1,933.11 tons of carbon per year. The changes in land use and cover are closely linked to this decline. In an effort to increase plant species diversity in the area and support the gradual transition away from monoculture, a participatory agroforestry scheme was implemented by intercropping Coffea liberica and Shorea balangeran between oil palm rows in a 2-hectare oil palm plantation block within the agroforestry demonstration plot. According to measurements taken at breast height, the aboveground biomass of these species was measured, leading to projected estimates of carbon stocks in Kepau Jaya specific purpose forest area reaching 19,455 tonnes of carbon by the year 2030, with Coffea liberica contributing 4,148 tonnes carbon and Shorea balangeran contributing 15,307 tonnes carbon. CONCLUSION: The study area experienced a substantial reduction in forest cover, whereas the extent of oil palm areas expanded significantly. The findings underscore the need for proactive measures to strengthen the governance of specific-purpose forest areas through community empowerment and the establishment of demonstration plots to promote agroforestry development. The results of this study provide insights for long-term forest rehabilitation strategies aimed at fostering sustainable forest management that yields environmental and socio-economic benefits in the long run. [ABSTRACT FROM AUTHOR]

[Objective] This study explored the effects of stand density of Caragana korshinskii plantation on species diversity and soil physical properties of herbaceous communities in sandy areas and determined the optimal stand density to provide references for better ecological service function. [Method] In Dalat Banner plantation of Ordos in the middle of Kubuqi Desert, Caragana korshinskii plantations with same site conditions, similar age and different stand densities were selected as the research objects. Woodlands with stand densities of 2 880-3 200 plants/hm² (I), 1 800-2 000 plants/hm² (II), 1 080-1 200 plants/hm² (III) and 720-800 plants/hm² (IV) were selected and compared with bare sandy land (CK). Species diversity of understory was characterized by herb community diversity.Height, cover and canopy width of plants in different stands were recorded.Soil water content, volume mass, field water capacity and total porosity were measured at soil layers of 0-20, 20-40, 40-60 and 60-80 cm by five-point sampling method.Correlations between plant community species diversity and soil physical properties were analyzed by redundancy analysis, and the principal components were used to evaluate Caragana korshinskii plantations. [Result] (1) There were 20 species of herbaceous plants, mainly Compositae.With the decrease of stand density, the Simpson, Shannon-Wiener and Margalef indices of herbaceous communities under Caragana korshinskii stand first increased and then decreased, and the order were in the order of III>IV>II> I>CK, while the Peilou evenness index showed no significant difference from CK. (2) Soil water content, total porosity and field water capacity of Caragana korshinskii plantation reached the peak values of 5.10%, 30.77% and 19.16% at density III.There was no significant difference in soil volume and mass among different plots (P>0.05). There were significant differences in soil moisture content between 0-40 cm and 40-80 cm soil layers (P<0.05).With the deepening of soil layer, volume quality of soil increased. (3) There were certain correlations between species diversity indices and soil physical properties in each density plot. (4) Comprehensive evaluation showed that plantations were in the order of III (2.276) > IV (1.261) > II (0.294) > I (-0.815) > CK (-3.017). [Conclusion] 1 080-1 200 plants/hm² was the appropriate density for the restoration of vegetation and soil physical properties of Caragana korshinskii plantation in the study area. [ABSTRACT FROM AUTHOR]

Invasive plants disrupt ecosystems by influencing species interactions, aiding co-invader integration, and worsening competition for native plants. Successful forest invasive species management relies on grasping these interaction patterns at the community level. This study aims to assess the community attributes of invasive plants in tropical forests of Northeast India, examining their dominance in various habitats, elucidating their influence at the community level and some species-specific effects on associated co-invaders and non-invasive groups. The present investigation recorded 101 invasive plant species mostly of neotropical origin, comprising of grasses, sedges, forbs, shrubs, trees, and vines. The findings revealed both positive and negative effects of invasive species richness and their percentage at community level and throughout different habitats. However, the presence of dominant invasive species caused a substantial decrease in species diversity of plant community in the study area, depicting a significant negative association with the non-invasive group and a notable positive association with the co-invasive group. These findings offer valuable insights by specifying the community-level impacts of exotic invaders on the natural plant population which will be very helpful in devising effective management plans to counter biotic invasion in the biodiversity rich tropical forested landscapes. [ABSTRACT FROM AUTHOR]

Protein, derived from plant and microbial residues, constitutes a significant portion of soil nitrogen or organic carbon pool and plays a crucial role in determining soil nitrogen and carbon sequestration. Though diversifying plant species has been regarded as a promising strategy for promoting soil nitrogen or organic carbon accumulation during vegetation restoration or afforestation, how increasing plant species diversity (PSD) would influence soil protein pool remains unknown. We selected 45 plots covering a natural gradient of PSD, which was reflected by the Shannon index and varied from 0.15 to 3.57, in a subtropical karst forest. The major objective was to investigate the impact of increasing PSD on soil protein abundance, with soil protein depolymerization rate and multiple biotic and abiotic variables being measured to explore the underlying mechanism. The relative abundance of soil protein, that is proportion in soil organic matter varied between 24.1 and 34.0% with an average of 29.2 ± 2.3% across the 45 plots. Soil protein abundance increased on average by 1.56% with each unit of PSD increase. Nevertheless, soil protease activity, protein depolymerization rate and microbial amino acid uptake rate all significantly (p < 0.05) decreased as PSD increased. The mechanism underlying the increase of soil protein abundance in response to higher PSD included three aspects, that is stimulating microbial biomass and subsequent microbial residue input to the soil, promoting mineral protection of soil protein via elevating levels of soil exchangeable calcium and magnesium, and decreasing soil protease activity and protein depolymerization due to aggravated soil microbial phosphorus limitation. Synthesis and application: Our study suggests that increasing PSD is an efficient way to promote soil protein accumulation. Given that protein is a major component of soil nitrogen or organic carbon pool, diversifying plant species during vegetation restoration or afforestation would hence benefit soil nitrogen and organic carbon sequestration. [ABSTRACT FROM AUTHOR]

In arid ecosystems, vegetation patches promote biological activity and ecosystem functioning through species interactions that mitigate adverse environmental impacts. However, overgrazing disrupts those interactions, contributing to desertification. We investigated livestock influence on spatial vegetation patterns through the modification of the frequency and type of associations (i.e. number of associated species within a vegetation patch) among types of successional species (i.e. early, intermediate, and late). We studied vegetation in nine rangelands with varying stocking rates (treatments) within the Monte Desert region. We postulated three hypotheses: (1) Grazing simplifies community structure, increasing the frequency of isolated individuals and reducing the association diversity among plant species; (2) competition between plants favors the associations among species with different ecological niche requirements, reducing competition, enhancing facilitation, and regulating the association frequency among species; (3) grazing modifies plant competition and patterns of association among species. We found that with increasing stocking rates, the frequency of isolated individuals increased while association diversity declined. Associations between species with dissimilar niche requirements (e.g. early–late) were more frequent than those with similar needs (e.g. early–early). Livestock grazing modified plant competition, leading to an increased frequency of associations among species with similar requirements. Therefore, the association frequency among types of species in these drylands clearly reflected the degradation process along a grazing gradient, aiding in understanding plant ecological interactions. The association frequency could be implemented as an indicator in diagnostic and monitoring stages of restoration processes. [ABSTRACT FROM AUTHOR]

Increasing densities of woody plants, known as woody plant encroachment, is a phenomenon affecting savannas and grasslands in many parts of the world. Yet, these ecosystems sustain a significant proportion of the human population through the provision of ecosystem services, such as forage for livestock and wildlife production. While low to medium altitude rangelands are encroached by many species of woody plants, high altitude rangelands in southern Africa show increasing densities of Leucosidea sericea, a woody shrub or small to medium-sized tree. Influences of this species on rangeland dynamics are unknown. This study aimed to determine the influence of L. sericea on rangeland functioning in the Vuvu communal area in the Eastern Cape, South Africa. Effects of L. sericea on plant species diversity and composition, rangeland condition and grazing capacity were measured in sites of variable densities of the species in topographical locations designated as plains, upland and stream sites, using a point-to-tuft method along 50-m long transects. Soil samples were collected to a depth of 5 cm from plains, streams, and upland sites, and analysed for organic carbon, nitrogen, phosphorus, magnesium, calcium, and pH. Plant species richness and abundance were similar among topographical locations, which was reflected by the similar Shannon-Weiner (H′) diversity indices among sites. Topographical locations differed significantly in species composition. The plains sites had a higher grazing capacity than stream sites, which had a grazing capacity similar to that of upland sites. Values of soil physicochemical properties were similar among the sites. Overall, soils were acidic (range in pH: 4.4–4.6) and had low amounts of organic carbon and total nitrogen. These findings suggest that L. sericea is not the primary cause of rangeland degradation as all sites were in poor condition as shown by the low grazing capacity, poor rangeland condition and depauperate species richness and diversity. Therefore, rangeland management should shift towards restoration strategies aimed to revitalise the rangeland. [ABSTRACT FROM AUTHOR]

The understory herbaceous flora plays a pivotal role in regulating the structural stability, complexity, and ecological function of forest communities. It is crucial to investigate the impact of the intricate connections between these factors and the forces driving the diversity of herbaceous species within natural broadleaf understory forests can assist forest managers in developing optimal forest structure optimization techniques, allowing them to adjust the forest species diversity. In this study, Pearson correlation analysis, conventional correlation analysis, and multiple linear regression were employed to elucidate the relationship between stand structure, soil nutrients, and understory herbaceous species richness in natural broadleaved forests. Structural equation modeling was utilized to ascertain the influence of multiple factors on understory herbaceous species diversity and to evaluate the underlying pathways. The results indicated a significant negative correlation between stand closure and the Simpson's and Shannon-Wiener's indices, and between the mixing degree and the Pielou evenness index, Simpson's index, and Shannon-Wiener's index (p<0.05). Furthermore, a significant positive correlation was observed between soil nutrients, specifically organic matter and total phosphorus, and the Pielou evenness index and Shannon-Wiener's index (p<0.05). It was found that total phosphorus was significantly positively correlated with both the Pielou evenness index and the Shannon-Wiener index (p<0.05). The correlation coefficients of the first group of typical variables in the typical correlation analysis were 0.498 and 0.585, respectively (p<0.05). From the set of typical variables of stand structure, it can be seen that the Hegyi competition index and the canopy density affected the diversity of understory herbaceous plants. The composite index demonstrated the greatest impact, with loadings of 0.872 and -0.506, respectively. The Simpson and Shannon-Wiener indices exhibited the most sensitive loadings of -0.441 and -0.408, respectively. The soil nutrients of SOM and TN affected the understory herbaceous plant species diversity composite index, with greater loadings of -0.184 and 1.002, respectively. The path coefficient of the understory herbaceous diversity stand structure was 0.35. The path coefficient with soil nutrient content was found to be 0.23 following structural equation analysis and the path coefficient between stand structure and soil nutrient content was 0.21, which indirectly affect the diversity of understory herbaceous species. To enhance the diversity of herbaceous species, it is recommended that the canopy density and tree density of the upper forest be reduced appropriately, while the degree of mixing and the level of spatial distribution of trees be adjusted in a manner that maintains a reasonable stand structure. Furthermore, a comprehensive forest management program for improving soil nutrients should be considered. [ABSTRACT FROM AUTHOR]

Questions: Herbivores change plant communities and biogeochemical cycles by changing species composition and soil organic matter contents through different mechanisms. Our objective was to evaluate the effects of livestock removal on plant species composition and soil organic matter stocks in savannas of the Río de la Plata grasslands. Locations: A subtropical savanna in Río Negro, Uruguay. Methods: The experiment consisted of a paired grazing exclusion randomized block design with five sites, where livestock was excluded for 29 years. We recorded differences in plant species composition in different strata and extracted soil cores to analyze soil carbon and nitrogen stocks, and δ13 carbon contents in two different soil organic matter fractions. Results: Long‐term livestock removal reduced plant species richness and diversity, altered the floristic composition and facilitated native‐shrub encroachment. Grazing exclusion modified the relative frequency of plant functional types and reduced summer‐growing grasses. We recorded 45 species common to both grazing and exclosure treatments, while 19 were present only in exclosure sites and 39 only in grazed sites. Livestock exclusion had a differential effect on soil organic matter formation, increased soil organic carbon and nitrogen stocks in the mineral‐associated organic matter (MAOM) but tended to slightly reduce them in the particulate organic matter fraction (POM). Grazing removal modified the C3/C4 species cover and these differences were reflected in the δ13C contents of both POM and MAOM fractions. Conclusions: Removal of domestic herbivores increased shrub abundance, decreased plant species richness and diversity but increased total carbon and nitrogen contents in soil organic matter. Our results suggest that grazed and exclosure areas should be combined mosaically in the landscape to maximize plant species diversity and soil organic carbon sequestration. [ABSTRACT FROM AUTHOR]

Environmental pollution with pesticides as a result of intensive agriculture harms the development of bee colonies. Bees are one of the most important pollinating insects on our planet. One of the ways to protect them is to relocate and build apiaries in populated areas. An important condition for the development of bee colonies is the rich species diversity of flowering plants and the size of the areas occupied by them. In this study, a methodology for detecting and distinguishing white flowering nectar source trees and counting bee colonies is developed and demonstrated, applicable in populated environments. It is based on UAV-obtained RGB imagery and two convolutional neural networks—a pixel-based one for identification of flowering areas and an object-based one for beehive identification, which achieved accuracies of 93.4% and 95.2%, respectively. Based on an experimental study near the village of Yuper (Bulgaria), the productive potential of black locust (Robinia pseudoacacia) areas in rural and suburban environments was determined. The obtained results showed that the identified blooming area corresponds to 3.654 m2, out of 89.725 m2 that were scanned with the drone, and the number of identified beehives was 149. The proposed methodology will facilitate beekeepers in choosing places for the placement of new apiaries and planning activities of an organizational nature. [ABSTRACT FROM AUTHOR]

Swahili coastal forests, spanning the Kenyan and Tanzanian coastlines and the Zanzibar Archipelago, are integral to the biodiverse Eastern Arc and Coastal Forest region. These forest ecosystems face considerable anthropogenic threats. This study contributes to the available knowledge on the floral composition and plant community assemblages of Mnemba Island, a small sandy cay in the Zanzibar Archipelago, which helps to establish baseline data for conservation purposes. Two main coastal forest plant communities were identified: (1) the Casuarina cunninghamiana–Suriana maritima open to closed sandy dry coastal forest, and (2) the Eugenia capensis–Mimusops obtusifolia coastal forest. A total of 91 different plant species belonging to 54 plant families were identified for the island. Community 2, an indigenous forest, supports diverse bird breeding colonies and is a crucial habitat for the threatened Aders' duiker. Understory development is limited due to the historical Suni antelope overpopulation. Environmental factors like salt spray, allelochemicals, herbivore browsing, and climate fluctuations influence the vegetation abundance and composition. The study underscores differences in species diversity and composition between the planted Casuarina community and the natural atoll vegetation. The natural vegetation shows affinities with the Zanzibar–Inhambane edaphic coral-rag scrub forest and the transitional rainforest. Several species characteristic of Indian Ocean atolls were identified, providing insights into invasion ecology and conservation strategies. The study contributes conceptually to our understanding of vegetation dynamics in island ecosystems by highlighting the interplay between plant communities, environmental processes, and human activities. The fragile yet resilient nature of Mnemba's unique ecosystem is emphasised, offering insights for conservation management, long-term monitoring, and adaptive approaches tailored to island environments. [ABSTRACT FROM AUTHOR]

The Mediterranean coasts are threatened by human activities that alter habitats structure and functionality, modifying vegetation and causing the loss of typical species. The definition of the conservation status of coastal habitats is essential to preserve these fragile environments through planned policies. This study aims to assess the conservation status of the habitats of community interest (sensu EEC Directive 43/92) through the analysis of biodiversity and correlating it with urbanisation. A total of 73 vegetation relevés were carried out, so allowing 13 revealing different habitats to be identified. The total plant species diversity per habitat was measured by means of the H-index, also used to assess naturalness (N), differently considering native, alien, and disturbance species. To correlate the N index with distance from urban centres, a statistical analysis was performed. The analysis showed the highest values of H+ were found in habitats 2240, 2110, 2260, and 2230, while lowest values were observed in habitats 2270* and 2240. The habitats 2270* and 2240, the closest to urban centres, have a lower naturalness score than habitats 1420, 2120, 2250*, and 2270*, where higher naturalness scores have been found and therefore lower levels of disturbance. The criteria and methods discussed in this study can be used in coastal management in order to identify the most sensitive habitats and implement an effective conservation strategy. [ABSTRACT FROM AUTHOR]

Secondary forests represent a significant proportion of global forest cover, with over 70% of forests in East Asia classified as regenerating. While succession has been studied extensively in temperate systems, trajectories of subtropical succession remain poorly characterized in highly disturbed, urban‐adjacent forests. Investigating the additive beta diversity components of turnover and nestedness may reveal community assembly mechanisms driving secondary succession. The present study investigates plant community assembly along a successional gradient from 7 to 70 years following the onset of succession in secondary subtropical forests in Hong Kong, China. Plant survey data for 28 plots were analysed, generating additive Simpsons turnover and nestedness beta diversity metrics. Dissimilarity matrices were generated and modelled as a function of environmental matrices including forest plant community age (years following onset of secondary succession), inter‐community distance (metres), and soil moisture saturation (%) across three elevational bands using generalized dissimilarity models. Nonmetric multidimensional scaling of plant communities was conducted with Bray–Curtis dissimilarity matrices. Inter‐community distance and successional age differentially influenced plant species turnover between lowland and Montane forest types. Models of nestedness found that plot age and soil moisture saturation were significant drivers of nestedness patterns in plant communities across elevational classes. Turnover represented a higher proportion of Sorensen beta diversity than nestedness, while ANOSIM found significant differentiation between plant communities at different successional stages. Turnover patterns suggest a deterministic model of community assembly, with strong patterns of species replacement between communities at fine spatial scales and successional stages, as well as clear compositional shifts between lowland and montane forest types. NMDS analysis and functional compositional assessments suggested a transition from early successional communities with a high proportion of shrub species, to later successional communities with a higher proportion of tree species, with an increase in species turnover with greater age dissimilarity. [ABSTRACT FROM AUTHOR]

The relationship between phytophagous insects and plants is a central aspect of food webs and ecosystem functioning. The introduction of new species into an environment can have significant impacts on the food web of a native ecosystem. In many cases, there is a lack of knowledge on the biology and feeding behavior of invasive species prior their introduction and in the invaded regions. Gut content analyses of insects have provided valuable information on the host spectrum of insects. However, current approaches are time‐consuming and costly. Here, we describe a new molecular gut content analysis (GCA) approach using the Oxford Nanopore (ONT) Flongle sequencing platform to characterize the plant DNA present in the gut of the highly polyphagous insect species Halyomorpha halys. We demonstrate that this technique efficiently amplifies and correctly identifies plant DNA in a mock community. We performed a feeding experiment to determine the sensitivity of this approach and to assess how long the plant DNA can be detected. All plants used in the feeding experiment were correctly identified and detected after 56 days. Surprisingly, we also detected various plant genera that were not included in the feeding experiment and thus were likely ingested months before the experiment. Our study suggests that the GCA using the ONT Flongle sequencing platform represents a rapid and cost‐efficient diagnosis of the dietary preferences, host range, and the diversity of consumed plant species of pest insects with high precision. [ABSTRACT FROM AUTHOR]

The great majority of studies on foundation species focused on a single dominant plant in a community, while more than one such species can often coexist and compete for space and limited resources. Morphologically different coexisting foundation species can create diverse niches occupied by different subsets of beneficiary species. To test this hypothesis, we sampled alpine plant communities at exposed fellfields in alpine zone, in the Taisetsu Mountains (Hokkaido, northern Japan), with coexisting putative foundation species Pinus pumila (evergreen shrub) and Diapensia lapponica (evergreen cushion‐forming shrub), and analyzed their spatial relationships with other plants. Preliminary vegetation survey indicated that fruticose lichens and Loiseleuria procumbens (evergreen mat‐forming shrub) might also act as a foundation species; thus, we included them in our analyses. The coexisting foundation species had both general as well as specific effects on plant community structure. Namely, almost all the members of the community aggregated spatially with lichens, while the other foundation species were spatially segregated from each other. These foundation plants associated with different members of the community, thus showing species‐specific effects on the community structure. Blooming species showed even stronger patterns of species‐specific spatial associations, suggesting that foundation species had beneficial effects on their associated species. We conclude that the focus on coexisting foundation species can reveal important details of community structure which would be hidden if we treated all species as equal members of the community. Studying the effects of coexisting foundation species could greatly advance our understanding of how species diversity functions in plant communities. [ABSTRACT FROM AUTHOR]

Vascular plants develop diverse root system architectures and exudates to facilitate acquisition of soil nutrients (nitrogen and phosphorus). Plant species have inherently specific properties of root system architectures and exudates, but some plants exhibit high plasticity to respond to spatiotemporal variations in soil nutrient forms and availability. This paper synthesizes evidence on how plant species diversity and root plasticity contribute to soil nutrient mobilization and uptake in plants from the tropics to the Arctic with varying plant species diversity. The development of finer roots in the surface soil is a well‐known strategy for the acquisition of limited nutrients (especially phosphorus), but the allocation of roots foraging "nutrient hotspots" in deeper soil (podzolic soil or permafrost‐affected soils) is an alternative strategy for coniferous trees tested in the Arctic and boreal forests. This contrasts with findings in tropical forests, where diverse plant species with different capacities of organic acid exudation coexist and species composition shifts in response to phosphorus deficiency. In particular, high malate exudation from roots and rhizosphere microbes stimulates phosphorus solubilization, aluminum detoxification, and lignin degradation in acidic soils. The diversity and plasticity of the root system architecture, root exudation, and the flexibility of nutrient sources mitigate nutrient limitation in soil. Root plasticity facilitating soil nutrient acquisition has a large impact on biogeochemistry and soil formation, such as podzolization, in the long term. [ABSTRACT FROM AUTHOR]

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 study aimed to assess the encroachment of woody plants on the rangelands of the Dallo Manna district of Bale Zone, and their impact on plant species diversity and pastoral livelihoods. Plant data were collected from 45 plots at encroaching sites and 4 plots at non-encroached sites, with a size of 20 m × 20 m for comparison. Data on pastoral perceptions were collected through questionnaires, interviews with key informants, and focus group discussions. A total of 62 woody species were recorded at both non-encroached and encroached sites, of which 58 species (93.5%) were recorded at non-encroached sites and 24 (38.7%) at encroached sites. Dichrostachys cinerea (L.) Wight and Arn. was the most abundant and dominant invasive woody species, followed by Senegalia mellifera (Vahl) Siegler and Ebinger, and Dalbergia microphylla Chiov. Overall, our results indicated that the effects of woody species encroachment significantly affected rangeland vegetation conditions and livelihoods. The major drivers for the encroachment were found to be fire suppression, overgrazing, and dispersal syndromes. However, in order to understand the exact causes of the woody plant encroachment, multiple variables should be considered in future research. For the successful control of encroachment, insights from an integrated approach will benefit from both local traditional and scientific knowledge of the ecology. [ABSTRACT FROM AUTHOR]

As one of the responses to the global commitments against climate change, the Ethiopian Government launched a nationwide Green Legacy Initiative (GLI) in 2019, which largely focused on forest tree plantations with some inclusion of fruit trees. Despite its tremendous efforts and investments, its effectiveness and impacts have not been studied. This paper attempted to address this necessity by conducting a cross‐sectional quasi‐experiment in three randomly selected woredas/districts of Lake Hawassa Watershed from August 20 to September 2, 2023. The research hypothesized the likely impacts of GLI on four dependent variables (hydrological regulation, soil stability, nutrient cycling and plant species diversity). To achieve this, the research considered the two variants of GLI practices (plantation with and without soil and water conservation measures) and the corresponding control sites. Having three sites and three treatments with five replications, the study involved a total of forty‐five quadrats of the same size (20 m × 20 m). The first three parameters were analysed using the landscape functionality analysis method, while the fourth employed Shannon's diversity index. Results of ANOVA showed that, on average 87% of randomly selected quadrats were found to significantly improve the local hydrology (runoff potential) (≈ 83.3% with Av. p = 0.012), soil stability (≈100% with Av. p = 0.002), nutrient cycling (≈83.3% with Av. p = 0.017) and plant species diversity (≈83.3% with Av. p = 0.012). The research revealed positive results from the Ethiopian Green Legacy Initiative. The small number of samples is acknowledged as a limitation of the research. [ABSTRACT FROM AUTHOR]

Vegetation restoration can alter carbon (C), nitrogen (N), and phosphorus (P) cycles in coastal wetlands affecting C: N: P stoichiometry. However, the effects of restoration age on soil C: N: P stoichiometry are unclear. In this study, we examined the responses of soil C, N, and P contents and their stoichiometric ratios to vegetation restoration age, focusing on below-ground processes and their relationships to aboveground vegetation community characteristics. We conducted an analysis of temporal gradients based on the 'space for time' method to synthesize the effects of restoration age on soil C: N: P stoichiometry in the Yellow River Delta wetland of China. The findings suggest that the combined effects of restoration age and soil depth create complex patterns of shifting soil C: N: P stoichiometry. Specifically, restoration age significantly increased all topsoil C: N: P stoichiometries, except for soil total phosphorus (TP) and the C: N ratio, and slightly affected subsoil C: N: P stoichiometry. The effects of restoration age on the soil C: N ratio was well constrained owing to the coupled relationship between soil organic carbon (SOC) and total nitrogen (TN) contents, while soil TP content was closely related to changes in plant species diversity. Importantly, we found that the topsoil C: N: P stoichiometry was significantly affected by plant species diversity, whereas the subsoil C: N: P stoichiometry was more easily regulated by pH and electric conductivity (EC). Overall, this study shows that vegetation restoration age elevated SOC and N contents and alleviated N limitation, which is useful for further assessing soil C: N: P stoichiometry in coastal restoration wetlands. [ABSTRACT FROM AUTHOR]

Ungulate herbivory might induce different effects on the diversity and growth of trees and shrubs. The density, distribution, and the species of ungulates as well as plant communities' composition and other factors determine whether ungulate herbivory promotes or limits plants' diversity and growth. The impacts of ungulates on woody plants are commonly surveyed with exclosure-control approaches. In practice, such surveys frequently only cover short periods of time, addressing immediate management needs. Long-term surveys, documenting lasting effects of ungulate herbivory, are highly needed, but still rare. However, the general transferability of outcomes of long-term surveys might be limited due to different disturbing factors. This study addresses two basic aspects of long-term monitoring in mountainous forests, based on a unique 30-year data set: (1) Possible long-term effects of herbivores on forest vegetation (e.g., species/structural diversity of woody plants) and (2) potential differences between short-term and long-term surveys in terms of height growth patterns. In our study, diversity of woody plant species showed great variability with no significant impact of ungulate herbivory. The presence of ungulates had a significantly negative effect on the vertical structural diversity and growth of trees. Due to the slower growth on control plots, it took trees longer to reach a 160 cm height-threshold with their terminal shoots than on exclosure plots. Our long-term control-exclosure data set indicated that long-term survey data indeed might differ from growth patterns represented by short-term surveys. This can be induced by several factors, like site-specific growth patterns of trees, occurrences of natural abiotic disturbances that influence the functional life of exclosures, and others. [ABSTRACT FROM AUTHOR]

Urbanization profoundly alters natural landscapes, leading to changes in species assemblages and ecological interactions. Despite increasing interest in understanding the effects of urbanization on species interactions, there is still a gap in knowledge regarding the structure of plant-herbivore networks in urban environments. Previous studies have indicated that anthropogenic impacts can alter the topology of plant-herbivore networks, making them more generalized in disturbed environments. Here, we investigate the topology of a plant-herbivore network in urban fragments of neotropical savanna in Brazil. As specialist species (i.e., those with few interactions) tend to be more sensitive to urbanization than generalist species (i.e., those with many interactions), we hypothesized that the urban savanna network would exhibit low specialization and modularity but high nestedness. We also tested if different attributes of insects (abundance, feeding guild, developmental stage, and taxon) and plants (abundance, height, and coverage) affect the diversity of their interactions at the species level. Contrary to our expectations, the network exhibited higher specialization and modularity than expected by null models, indicating urban environments may foster levels of specialization comparable to observed in previous studies for wild savannas. Regarding the species-level descriptors, we found that different characteristics of insect and plant species affect the diversity and specialization of their interactions. Our results showed that adult insects have higher degree and centrality in shaping the network, possibly attributed to their increased mobility and capacity to link various segments of the network. Similarly, chewing insects and thrips (Thysanoptera), known for their generalist interactions with plants, had higher number of interactions and were central within the network. Furthermore, larger plant species had a higher degree and greater betweenness centrality, while plant species with greater cover had lower specialization compared to herbs. This indicates that plant species with greater structural complexity accumulate more generalized interactions. Our results also show that more abundant species, both insects and plants, had a higher number of interactions and greater centrality in the network. Our study provides insights into the structure of plant-herbivore networks in urban savanna fragments, contributing to our understanding of species interactions in urban environments and their response to anthropogenic pressures. [ABSTRACT FROM AUTHOR]

Introduction: Understanding how human activities affect biodiversity is needed to inform systemic policies and targets for achieving sustainable development goals. Shallow tillage to remove Artemisia ordosica is commonly conducted in the Mu Us Desert. However, the impacts of shallow tillage on plant community species diversity, phylogenetic structure, and community assembly processes remain poorly understood. Methods: This study explores the effects of shallow tillage on species diversity including three a-diversity and two b-diversity indicators, as well as phylogenetic structure [phylogenetic diversity (PD), net relatedness index (NRI), and nearest taxon index (NTI)]. Additionally, this research analyzes the effects of shallow tillage on the community assembly process. Results and discussion: The results showed that the a-diversity index, b-diversity index, and PD of the shallow tillage (ST) communities were significantly higher than those of the non-shallow tillage (NT) communities, and the phylogenetic structures of both the ST and NT communities tended to be differentiated, with competitive exclusion being the main mechanism of plant assembly. However, shallow tillage increased the relative importance of the stochastic processes dominated by dispersal limitation, mitigating plant competition in the communities. This conclusion was supported by the Raup-Crick difference index-based analysis. Conclusion: Therefore, for the ecological restoration of the Mu Us Desert, species with adaptability and low niche overlap should be selected to increase the utilization efficiency of the environmental resources. The results of this study provide a foundation for policy development for ecosystem management and restoration in the Mu Us Desert. [ABSTRACT FROM AUTHOR]

Introduction: The Indian Himalayan forests are remarkable landforms experiencing tremendous climatic variation, constituting complex and diversified ecosystems with prominent vegetation zones. Despite their global significance and substantial research efforts focused on plant diversity in the temperate Himalayan region, only a few studies have explicitly assessed the distribution patterns of understory vegetation in relation to forest compositional types along altitudinal gradients. Methods: To cover a wide range of altitudes and diverse overstory compositions, stands were sampled across four altitudinal ranges from 1500 to 3500 meters above mean sea level with increments of 500 meters in elevation steps. The overstory compositions were classified on the basis of dominant tree species in each stand on the similar sites. Vegetation in the shrub and ground layers was surveyed by visually estimating the percentage coverage within circular plots. Results: A total of 99 understory species including 37 species each in the shrub layer, 62 species in the herb layer vegetation were recorded. The abundance, species diversity and composition of understory vegetation differed significantly along the altitudinal gradient and dominant overstory composition types. Moreover, distinct understory vegetation communities were observed at lower elevations compared to higher elevations, with middle elevations exhibiting intermediate vegetation characteristics. The study also highlighted the importance of dominant overstory composition types in shaping the pattern of understory vegetation abundance, species diversity and composition in the temperate Himalayan region. The higher resource conditions associated with broadleaved stands supported higher understory species abundance at lower elevations, while the heterogeneous conditions induced by the mixedwood stands promoted higher understory species diversity. Conclusion: The hump shaped pattern along the altitudinal gradient appeared to be the most dominant pattern of plant abundance and species diversity and call for more conservation concern towards the middle elevation zones in the temperate Himalayan region. Furthermore, the management interventions should aim at maintaining diverse range of overstory composition types for conserving biodiversity and their ecological functions in the temperate Himalayan region. [ABSTRACT FROM AUTHOR]

Restored wetlands should be closely monitored to fully evaluate the effectiveness of restoration efforts. However, regular post-restoration monitoring can be time-consuming and expensive, and is often absent or inadequate. Satellite and airborne remote sensing systems have proven to be cost-effective tools in many fields, but they have not been widely used to monitor ecological restoration. This study assessed the potential of airborne hyperspectral remote sensing to monitor water mass characteristics of experimental temporary ponds in the Mediterranean region. These ponds were created during marsh restoration in Doñana National Park (south-west Spain). We used hyperspectral images acquired by the CASI-1500 hyperspectral airborne sensor to estimate and map water depth, turbidity and chlorophyll a in a subset of the 96 new ponds. The high spatial and spectral resolution of the CASI sensor allowed us to detect differences between ponds in water depth, turbidity and chlorophyll a, providing accurate mapping of these three variables, and a useful method to assess restoration success. High levels of spatial variation were recorded between different ponds, which likely generates high diversity in the animal and plant species that they contain. These results highlight the great potential of hyperspectral sensors for the long-term monitoring of wetland complexes in the Mediterranean region and elsewhere. [ABSTRACT FROM AUTHOR]

The eastern population of monarch butterflies (Danaus plexippus) has dramatically declined in the last few decades, which is largely attributed to a loss of milkweed habitat in agricultural areas. Residential land in metropolitan areas has the potential to provide a significant source of the milkweed needed to support the monarch population. To examine if and how urban milkweed patches can support monarch butterflies, we worked with community scientists in the Chicago metropolitan area to monitor monarch eggs and caterpillars in yards and community gardens. We hypothesized that the largest numbers of eggs (i.e. gardens that were most attractive to monarchs) would be observed in patches that were older, had a high abundance of milkweed, contained more than one species of milkweed including Asclepias syriaca (common milkweed) and/or A. incarnata (swamp milkweed), and had a large diversity of nectar plants. All patches were assessed at their peak egg count each year, which ranged from zero to 170 eggs in a given observation. To determine which characteristics were most influential to egg presence, we examined patches where eggs were present or absent during this peak observation. For abundance, we divided these peak observations into whether or not the egg counts were in the top 20% in a given year, excluding patches where eggs were absent, and assessed their patch characteristics. Our results show that patch age and presence of A. syriaca affected whether patches contained eggs or not. We also found that patches with the largest number of eggs observed tended to have A. syriaca, more milkweed plants, and a higher diversity of blooming plant species. The data we collected from community scientists in the Chicago area has enhanced our understanding of how urban gardeners can create effective breeding habitats for monarch butterflies. By planting Asclepias syriaca within its natural range, along with other native milkweed species and a diverse selection of flowering plants, individuals can create gardens that serve as excellent habitats for monarchs and other pollinators. [ABSTRACT FROM AUTHOR]

Forest fires play a pivotal role in influencing ecosystem evolution, exerting a profound impact on plant diversity and community stability. Understanding postfire recovery strategies holds significant scientific importance for the ecological succession and restoration of forest ecosystems. This study utilized Partial Least Squares Path Modeling (PLS-PM) to investigate dynamic relationships among plant species diversity, phylogenetic diversity, soil properties, and community stability during various recovery stages (5-year, 15-year, and 23-year) following wildfires on the northeastern margin of the Qinghai-Tibet Plateau. The findings revealed: (1) Over time, species richness significantly decreased (p< 0.05 or p< 0.01), while species diversity and dominance increased, resulting in uniform species distribution. Community stability progressively improved, with increased species compositional similarity. (2) Throughout succession, phylogenetic diversity (PD) significantly decreased (p< 0.01), accompanied by rising Mean Pairwise Distance (MPD) and Mean Nearest Taxon Distance (MNTD). Net Relatedness Index (NRI) shifted from positive to negative, indicating an increasing aggregation and dominance of plants with similar evolutionary traits in burned areas. Early succession witnessed simultaneous environmental filtering and competitive exclusion, shifting predominantly to competitive exclusion in later stages. (3) PLS-PM revealed that in the early recovery stage, soil properties mainly affected community stability, while species diversity metamorphosed into the primary factor in the mid-to-late stages. In summary, this study showed that plant diversity and phylogenetic variation were successful in revealing changes in community structure during the succession process. Soil characteristics functioned as selective barriers for plant communities during succession, and community stability underwent a multi-faceted and dynamic process. The soilplant dynamic feedback continuously enhanced soil conditions and community vegetation structure thereby augmenting stability. Post-fire vegetation gradually transitioned towards the original native state, demonstrating inherent ecological self-recovery capabilities in the absence of secondary disturbances. [ABSTRACT FROM AUTHOR]

Vegetation plays a crucial role in the terrestrial ecosystem and can serve as a valuable indicator of environmental change. Studying the flora is of importance for protection and utilization of plant resources. Furthermore, understanding the composition and distribution of vegetation not only enhances plant biodiversity and quality but also enables us to make scientific use of plant resources. The ecological transition zone, known for its high species diversity, is an essential area for studying the flora. Qilian Mountain region, as an ecological transition zone, exhibits high plant diversity. However, the flora composition in this area has not been systematically documented. In order to ensure the accuracy of the species list and explore the distribution of flora, we conducted preliminary statistics by collecting and organizing scattered data from the literature. Subsequently, we used the plant specimen information to proofread and determine the flora composition. The results were as follows: (1) Qilian Mountains region had 1 952 species of vascular plants, belonging to 108 families and 527 genera, including 44 species of national protected plants and 100 species of threatened plants. (2) The dominant plant types in Qilian Mountain region were herbaceous, followed by shrubs, with trees being the least abundant. Most of these plants exhibited cold-resistance and drought-tolerance, with the majority being oligotrophic genera (the genera containing only one plant in Qilian Mountain region). The geographical components of the flora were diverse, but the temperate elements were predominant. (3) Species richness was the highest in the eastern region of the mountain, followed by the middle region, and the lowest in the western region. As longitude increased westward, the similarity index decreased. This suggests that the species composition and geographical components are synthetically influenced by local climatic conditions, topographic conditions, and diverse habitat types. (4) The presence of endemic species was significant, with a total of 717 endemic species in China and 45 endemic species in Qilian Mountain region, reflecting the uniqueness, diversity, and complexity of the ecosystem in the important region. In short, the flora of Qilian Mountain region is characterized by youthfulness. As an ecological transition zone, the region has extremely rich plant species diversity and breeds a large number of rare plants. Due to the large longitude span of the Qilian Mountain region, there are great differences in plant types between the eastern and western regions. The above results provide background data and a scientific reference for the maintenance of species diversity, sustainable development, and utilization of resources in this area. [ABSTRACT FROM AUTHOR]

Deserts are subject to significant anthropogenic pressure. The capacity to buffer against changes in the local environment and biodiversity are critical for ecosystem functioning. Foundation species can be a solution to rapidly assess ecological function and provide a simple nature‐based solution to protect against continuing biodiversity losses. A foundation species is defined as a species that exerts and promotes a positive set of processes for the biotic network. Two different shrub species in the central drylands of California were used to assay a potential buffer for plant species richness and to examine the species‐specificity of foundation facilitation. A five‐year dataset in two distinct regions differing in aridity was used to test the hypothesis that the direct effects of foundation plants facilitate other plant species and buffer diversity losses to a changing climate. The predicted positive effects of both shrub species on species richness increased with increasing local temperatures sampled. Finally, projected temperature increases for the region in trained Bayesian models demonstrated that both shrub species can profoundly increase in their capacity to facilitate plant species richness. Colloquially, this positive ecological effect can be described as the patronus charm hypothesis because regardless of the form of the protector, shrub species provided a talisman against local loss of richness driven by temperature increases. [ABSTRACT FROM AUTHOR]

The relationship between aboveground biomass and plant diversity has been extensively examined to understand the role of biodiversity in ecosystem functions and services. Degraded grassland restoration projects can enhance carbon sequestration. However, the relationship between biomass and diversity remains one of the most actively debated topics regarding grassland ecosystems in degraded grassland restoration projects. We speculated that establishing the linear relationships between aboveground biomass and plant species diversity could contribute to enhancing the efficacy of degraded grassland restoration projects. This study sought to determine whether these relationships were linear during the initial stages of the restoration projects of degraded grasslands in Xing'an League, China. The investigations were based on an examination of seventy‐six 1 × 1 m2 plots distributed among 15 areas in which the degraded grassland was at the initial stages of restoration. To quantify the species diversity of the degraded grassland communities, we used the species richness, Shannon–Wiener, inverse Simpson's reciprocal, and Pielou's evenness indices. Our analyses revealed that aboveground biomass had clear positive linear relationships with species richness during the initial stages of degraded grassland restoration. However, there were less pronounced associations with species diversity as assessed using the Shannon and inverse Simpson indices, based on regression models. Furthermore, weed biomass was found to have significant negative effects on species richness and Pielou's evenness. The weak linear relationship between aboveground biomass and species richness could be ascribed to an increase in weed biomass. We concluded that aboveground biomass and plant species diversity could be enhanced during the initial stages of degraded grassland restoration projects and suggest that the extent of weed biomass could serve as a key indicator of the efficacy of restoration from the perspective of plant species diversity and aboveground biomass in carbon sequestration projects. [ABSTRACT FROM AUTHOR]

The conservation biology field underscores the importance of understanding genetic diversity and gene flow within plant populations and the factors that influence them. This study employs Simple Sequence Repeat (SSR) molecular markers to investigate the genetic diversity of the endangered plant species Saussurea involucrata, offering a theoretical foundation for its conservation efforts. Utilizing sequencing results to screen SSR loci, we designed and scrutinized 18 polymorphic microsatellite primers across 112 samples from 11 populations in the Bayinbuluke region. Our findings reveal high genetic diversity (I = 0.837, He = 0.470) and substantial gene flow (Nm = 1.390) among S. involucrata populations (China, Xinjiang), potentially attributed to efficient pollen and seed dispersal mechanisms. Principal Coordinate Analysis (PCoA) indicates a lack of distinct genetic structuring within the Bayinbuluke populations. The cluster analysis using STRUCTURE reflected the genetic structure of S. involucrata to a certain extent compared with PCoA. The results showed that all samples were divided into four groups. To safeguard this species, we advocate for the in situ conservation of all S. involucrata populations in the area. The SSR markers developed in this study provide a valuable resource for future genetic research on S. involucrata. [ABSTRACT FROM AUTHOR]

The stability, diversity, and biomass of grassland plant communities directly impact the functionality and resilience of ecosystems, making them a focal point for ecological research. This three-year study (2021–2023) in the Habahe pastoral area of Xinjiang, China, aimed to investigate the long-term effects of grazing on grassland vegetation structure, community stability, species diversity, and productivity. The results indicate the following. (1) The Habahe pastoral area hosts a relatively rich plant species diversity, with 40 species distributed across 17 families and 37 genera, predominantly comprising perennial and annual herbs. (2) Grazing significantly affected grassland structure and function, resulting in a 4.35% decrease in plant community stability, a 40.74% decrease in species richness, a 21.55% decrease in species dominance, a 5.08% decrease in species diversity, a 46.79% decrease in aboveground biomass, a 61.86% decrease in coverage, and a 72.12% decrease in height. (3) Grazing alters the relationship between species diversity and community stability, shifting it from a positive correlation to a negative one (p < 0.01) or rendering it non-significant after grazing. (4) Grazing affects the correlation between aboveground biomass and both species diversity and community stability. While the positive correlation between aboveground biomass and species diversity persists, it is not statistically significant (p > 0.05) after grazing. Conversely, the correlation between aboveground biomass and community stability shifts from positive to negative (p < 0.01). These results emphasize the need for integrated management strategies that consider both grazing intensity and plant community composition to maintain the health of grassland ecosystems. [ABSTRACT FROM AUTHOR]

Till now, the diversity of entomopathogenic fungi in subtropical mountain forest was less studied. Here, the vertical distribution of forest soil fungi, entomopathogenic fungi, and their environmental influencing factors in a subtropical mountain in western China were investigated. Soil samples were collected from four elevations in a subtropical forest in Shaanxi. The results indicated a greater richness of soil fungi at middle elevations and soil fungi were more even at low elevation. Soil pH, available iron, available potassium, total potassium, and available zinc were the most important influencing factors affecting this vertical distribution of fungi. Interestingly, the Isaria genus was predominant while Metarhizium and Beauveria showed decreasing abundance. The presence of Isaria showed a significant positive correlation with both total phosphorus and available iron, while, available zinc was negatively correlated. Metarhizium was influenced by elevation, pH, available phosphorus, and available copper and Beauveria was influenced by soil organic carbon, total nitrogen, total potassium, available potassium, and available zinc. Overall, as environmental factors affecting soil fungi, elevation, and plant species diversity were less important than soil physical and chemical properties. The virulence of isolated entomopathogenic fungi were tested against larvae of Tenebrio molitor, with mortality ranging from 31.11% to 100%. The above findings provide valuable data to deepen our understanding of the diversity of entomopathogenic fungi in subtropical mountain forests. [ABSTRACT FROM AUTHOR]

Drought is a major stressor to soil microbial communities, and the intensification of climate change is predicted to increase hydric stress worldwide in the coming decades. As a possible mitigating factor for the consequences of prolonged drought periods, above and belowground biodiversity can increase ecosystem resistance and resilience by improving metabolic redundancy and complementarity as biodiversity increases. Here, we investigated the interaction effect between plant richness and successive, simulated summer drought on soil microbial communities during a period of 9 years.To do that, we made use of a well-established biodiversity experiment (The Jena Experiment) to investigate the response of microbial richness and community composition to successive drought periods alongside a plant richness gradient, which covers 1-, 2-, 4-, 8-, 16-, and 60-species plant communities. Plots were covered from natural precipitation by installing rain shelters 6 weeks every summer. Bulk soil samples were collected 1 year after the last summer drought was simulated. Our data indicate that bacterial richness increased after successive exposure to drought, with the increase being stable along the plant richness gradient. We identified a significant effect of plant species richness on the soil microbial community composition and determined the taxa significantly impacted by drought at each plant richness level. Our data successfully demonstrates that summer drought might have a legacy effect on soil bacterial communities. [ABSTRACT FROM AUTHOR]

The Cerrado is home of the headwaters of some important Brazilian basins. Such biome has a high diversity of animal and plant species with a high degree of endemism. This premise is well documented for microcrustaceans of the Superorder Cladocera, although many areas still need sampling. In this context, the objective of the present investigation was to evaluate the geographic distribution and richness of Cladocera in the Cerrado biome. The analyzed data were obtained from the authors database on Brazilian Cladocera and distributed according to the hydrographic regions comprised in the biome. Species distribution models were used to determine the areas with the highest probability of occurrence of Cladocera. We analyzed 125 publications, resulting in 2829 records. In total, we obtained 161 taxa, belonging to 48 genera and seven families. Regarding the Hydrographic Regions, Paraná presented the highest richness, followed by TocantinsAraguaia and São Francisco. Our result indicates that most studies are concentrated in certain areas. Furthermore, the species distribution models indicated that transition areas between biomes have the highest probability of occurrence of genera and families. Our results indicate significant gaps in the knowledge, making it necessary to expand inventories and ecological studies in areas still unsampled. [ABSTRACT FROM AUTHOR]

To understand the role of Apis cerana cerana in olive tree (Olea europaea L.) pollination, pollinators and pollen carried by bees were collected from 11 experimental plots during the flowering period. The abundance and diversity of pollen plant species were investigated using DNA metabarcoding. A total of 583 pollinators were collected and A. cerana cerana accounts for 46.83%. Further analysis revealed a total of 56 families, 136 genera and 195 plant species in bee pollens. O. europaea is the dominant species accounting for 42.02 ± 34.89% and then followed by Sedum japonicum (8.70 ± 16.42%). Diversity index showed that the abundance and diversity of pollen plant species were the highest in Wanzhou (WZ) and lowest in Hechuan (HC). This suggests that Wanzhou sample plot has a greater abundance of plant species to supplement the bee diet. Excessive presence of miscellaneous flowering plants in olive plantations can distract bees from collecting olive tree pollens. Therefore, their abundances can be reduced appropriately while ensuring food diversity for the bees. Based on the abundance of plants in pollens, we recommend that appropriately planting of S. japonicum, Youngia japonica and Vicia villosa in olive plantations with fewer flowering plants could be an effective supplement of bee food. Our results not only contribute to future studies on olive tree pollination but also provide new ideas for enriching flowering plants in or around olive plantations. [ABSTRACT FROM AUTHOR]

Urbanization has resulted in deterioration of natural lands and extinction of indigenous species. Domestic gardens are neglected spots of plants biodiversity. This research aimed to assess domestic garden plants diversity, composition, distribution, and identify the conserved indigenous plant species in a heavily urbanized arid city. Domestic gardens within each district were randomly selected, visited, and surveyed. Cultivated plant species in gardens were identified and counted; their frequencies and abundance levels were calculated. Plant species richness, Shannon, evenness, and Simpson's indices were calculated. More than 12,000 plants belonging to 223 plant species compromising 72 plant families were found. Domestic gardens played a significant role in conserving regionally extinct or endangered native plant species while undesirably sustained exotic and invasive plants. Overall, exotic plants species represented 84% of all identified species. The highest percentage of native plants (29%) was found in Uhod district, while the lowest (11%) was in Jubaiha district. The minimum and maximum proportion of medicinal, poisonous, and fruit bearing plants on a district bases were 9–26%, 9–22%, and 11–43% of domestic garden plants, respectively. The highest species richness (103) was in Zahran, while the lowest (20) was in Al-Madinah district. Shannon diversity index was the highest in Zahran and Sweileh districts. Shannon, evenness, and Simpson diversity indexes revealed Badr Al-Jadidah as the lowest plant diversity district. District history, lots sizes, garden sizes, socioeconomic status, residents' preferences, and housing regulations resulted in variation in plants diversity and species composition. Thus, monitoring species composition in domestic gardens and raising public awareness about plants benefits/risks supports environmental sustainability. Attention should be given to these neglected biodiversity hotspots, especially in arid environments. [ABSTRACT FROM AUTHOR]

Native fescue grassland degradation and reductions in plant species diversity due to smooth brome (Bromus inermis Leyss.) invasion and dominance have far ranging consequences for both human and ecological systems. A study was undertaken to reduce smooth brome which was invading foothills fescue grassland in Canada and displacing native species. Sheep and cattle grazing, mowing, glyphosate, and burning were applied to control smooth brome-dominant grasslands over three growing seasons. Defoliation (5 to 10 cm, 2 to 4 times) did not reduce smooth brome tiller density, etiolated regrowth, or total non-structural carbohydrates; however, the three heaviest defoliation treatments (sheep 3×, cattle 3×, mowing 4×) reduced smooth brome composition by year 3. Repeated glyphosate wicking (1× year 1, 2× year 2) was the most effective treatment and reduced smooth brome tiller density by 50% by year 3. Early-spring burning, as smooth brome began to grow, stressed the plants and reduced tiller density. Kentucky bluegrass (Poa pratensis L.), the subdominant species, increased in all treatments except the reference; thus, reducing smooth brome may result in another undesirable species becoming dominant. [ABSTRACT FROM AUTHOR]