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• 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]

Understanding how the complexities of biodiversity are maintained on islands has long been one of the central issues studied in conservation biology. With the global onset of anthropogenically driven biodiversity changes, the influence of anthropogenic activities challenges the applicability of the widely accepted Equilibrium Theory of Island Biogeography (ETIB). This study aimed to test how island area, isolation (MD: distance to the mainland, and ND: distance to the nearest island), and human activities (habitat heterogeneity, and proportion of road area relative to island area to refer to the human impact on island) separately and jointly affect the species diversity of vascular plants. The number of plant species with different growth forms (woody plants, herbs, and lianas) was calculated on 35 islands in Sanyang Wetland, which is a human-dominated wetland near the highly populated city of Wenzhou, China. We also evaluated the relative importance of these variables on the number of species using a random forest analysis. The number of species increased with increasing island area and habitat heterogeneity and decreased with increasing isolation for different growth forms. A significant, positive relationship was observed between the number of species and the proportion of road area for herbs, but not for woody plants and lianas. Habitat heterogeneity was the most important predictor for all plants, the proportion of road area was the most important predictor for herbs, and MD was the most important predictor for woody plants and lianas. These results indicate that ETIB remains relevant in the context of human disturbance, but the relative importance of ecological processes on species diversity differs significantly among plant growth forms. Therefore, we should consider plant functional groups when testing multifactorial effects on species diversity on human-dominated islands. [ABSTRACT FROM AUTHOR]

Agricultural intensification is a persistent and growing threat to biodiversity worldwide. Olive groves cover extensive areas in the Mediterranean basin and play a fundamental role as refuge and wintering quarters for many bird species, but the effects of their current intensification on bird communities remain unclear. This study aims to evaluate the response of wintering birds to the management of olive groves with different degrees of intensification (traditional, intensive and super-intensive management) in central Spain. Based on two bird censuses conducted in 25 groves in early and late winter, we examined the influence of habitat structure and composition at different spatial scales on species richness and abundance of the entire farmland bird community, and of the diet-based functional groups. Total species richness tended to decrease with intensive olive grove management, probably due to reduced habitat heterogeneity, whereas total abundance did not, indicating the capacity of intensive and super-intensive olive groves to sustain large numbers of wintering birds. The negative effect of intensification was particularly evident in frugivore species richness, while frugivore abundance was positively (but marginally) associated with olive fruit availability. Granivorous species were positively associated with lower vegetation cover, but insectivorous species did not respond to intensification gradients. Species richness and abundance (total and by diet-based functional groups) also decreased from early to late winter, which may be due to the effect of olive harvest, but also to an extreme cold event. Overall, our findings show how olive grove intensification and the associated management practices result in significant changes in habitat structure and composition at different spatial scales, thus affecting wintering bird communities. [ABSTRACT FROM AUTHOR]

The diversity of terrestrial vascular plants plays a key role in maintaining the stability and productivity of ecosystems. Monitoring species compositional diversity across large spatial scales is challenging and time consuming. Airborne hyperspectral imaging has shown promise for measuring plant diversity remotely, but to operationalise these efforts over large regions we need to advance satellite-based alternatives. The advanced spectral and spatial specification of the recently launched DESIS (the DLR Earth Sensing Imaging Spectrometer) instrument provides a unique opportunity to test the potential for monitoring plant species diversity with spaceborne hyperspectral data. This study provides a quantitative assessment on the ability of DESIS hyperspectral data for predicting plant species richness in two different habitat types in southeast Australia. Spectral features were first extracted from the DESIS spectra, then regressed against on-ground estimates of plant species richness, with a two-fold cross validation scheme to assess the predictive performance. We tested and compared the effectiveness of Principal Component Analysis (PCA), Canonical Correlation Analysis (CCA), and Partial Least Squares analysis (PLS) for feature extraction, and Kernel Ridge Regression (KRR), Gaussian Process Regression (GPR), and Random Forest Regression (RFR) for species richness prediction. The best prediction results were r = 0. 76 and RMSE = 5. 89 for the Southern Tablelands region, and r = 0. 68 and RMSE = 5. 95 for the Snowy Mountains region. Relative importance analysis for the DESIS spectral bands showed that the red-edge, red, and blue spectral regions were more important for predicting plant species richness than the green bands and the near-infrared bands beyond red-edge. We also found that the DESIS hyperspectral data performed better than Sentinel-2 multispectral data in the prediction of plant species richness. Our results provide a quantitative reference for future studies exploring the potential of spaceborne hyperspectral data for plant biodiversity mapping. [ABSTRACT FROM AUTHOR]

The environmental heterogeneity–biodiversity relationship is generally hypothesised to be positive, with greater heterogeneity leading to greater biodiversity. However, the generality of positive environmental heterogeneity–species richness relationships is often debated, with some studies finding non-significant or even negative relationships. Negative relationships have primarily been found at fine spatial scales. Both negative and positive relationships have a basis in ecological theory. Environmental heterogeneity at coarse scales opens up niche space to allow more species to coexist; whereas high local heterogeneity, for instance in topography, may lead to increased local extinction due to micro-fragmentation, or dominance of species suited to heterogeneous conditions. However, it is difficult to attribute how much of the variance is explained at different scales within the same modelling framework. Here, we use a new data-aggregation method which enables us to include both fine- and coarse-scale environmental heterogeneity within the same analysis. Using this method, we were able to tease apart the fine- and coarse-grain effects of topographic heterogeneity on European tree species richness. At the coarse scale (0.5 degrees), we found a positive effect of range in elevation on tree species richness. However, when measuring range in elevation using a fine-scale moving window of radius 500 m, we found a negative relationship with tree species richness. This supports existing research that has shown negative relationships between environmental heterogeneity and species richness at finer spatial grains. Because we were able to include a measure of both local and landscape-scale topographic heterogeneity in the same model, for the first time we could fully capture the effects of both scales on coarse-grain species richness while accounting for the effect of the other scale. [ABSTRACT FROM AUTHOR]

Urban greenspaces are critical for maintaining biodiversity and people's connection to nature. Schools are distributed throughout cities and have the potential to provide for and enhance native biodiversity, while facilitating positive relationships between children and nature. However, very little is known about greenspaces on school grounds, particularly their ecological condition. We evaluated the size and quality of greenspaces in 64 urban primary schools in Auckland, Aotearoa–New Zealand by undertaking a rapid greenspace assessment to identify the relative proportions of greenspace types on school grounds, vegetation and habitat quality. All schools had trees present on their grounds, however only 36 % had a native forest patch, and habitat quality was generally low due to the dominance of sports fields, artificial turf and a lack of shrub layer. A larger number of different greenspace types on school grounds was associated with more large trees (>6 m), and a higher habitat quality score. A third of schools also had one or more environmental weed species present. The socio-economic status of schools did not appear to be a key factor in predicting the quality of a school's greenspace. There are many opportunities to improve school greenspaces to better contribute to urban biodiversity as multifunctional spaces. Increasing greenspace type diversity, adding more vegetation layers, and increasing the diversity of native plant species on school grounds, would increase habitat complexity and improve biodiversity and cultural connection outcomes. The value of school grounds as multifunctional spaces will depend on place-specific ecological and cultural contexts. [ABSTRACT FROM AUTHOR]

Biofiltration systems can fail over time due to clogging by fine sediments in stormwater. Infiltration can be maintained by plant roots, but species selection for biofiltration to date has largely been driven by pollutant removal efficiency and tolerance of conditions. As a result, plant species diversity in biofilters is typically low and dominated by sedges and rushes. Increased use of woody species could in theory improve plant diversity, aesthetic appeal, infiltration under high sediment loads and volumetric runoff reduction via higher evapotranspiration, without jeopardising nutrient pollutant removal. We tested whether shrubs could maintain infiltration and evapotranspiration in biofiltration profiles treated with a high sediment load, by comparing them with biofilters subjected to tap water without sediment. Following sediment application, biofilter columns planted with shrubs with high total biomass and total root length showed higher infiltration and evapotranspiration than those receiving tap water. These results indicate that shrub species are likely to alleviate clogging and increase stormwater retention in biofiltration systems. However, shrubs with a high root diameter also had low total biomass and total root length and showed 33–51 % lower infiltration rates after sediment application compared with those receiving tap water. As all shrubs had higher root diameters than typical sedges and rushes, we suggest that shrubs need a combination of higher total biomass, total root length and average root diameter to effectively maintain infiltration. While shrubs which maintained infiltration had traits associated with high nutrient removal, nutrient removal efficiency of shrubs needs to be quantified. Although root traits were related to maintenance of infiltration, above-ground stems likely created flow pathways through sediment which requires further investigation. Overall, selecting shrub species with high total biomass has the potential to maintain infiltration and increase evapotranspiration in biofiltration systems impacted by high sediment loads. [ABSTRACT FROM AUTHOR]

• The influence of maintenance on biodiversity (plants and wildlife) in different types of urban green spaces varied and depended on the type of maintenance. • There was constant evidence of a negative association between mowing intensity and various aspects of plant diversity. • Approximately sixty percent of papers on invertebrates showed mixed effects of mowing intensity on this group's diversity. • More studies are needed on the association between biodiversity and chemical input, as well as other maintenance practices. Most urban green spaces (UGSs) today are under intensive maintenance practices, including mowing, cutting and/or chemical input, among many other practices. A growing body of research has questioned the biodiversity value of highly manicured UGSs and suggested the biodiversity potential of reduced-intensity maintenance regimes. However, the evidence for a relationship between maintenance and biodiversity in UGSs is still unclear and yet to be fully understood. This paper systematically reviews 92 published papers to examine this association. Our results showed a complex association between maintenance and biodiversity, mainly dependent on the type of maintenance practice studied and the measurement of biodiversity. Mowing was the predominant maintenance practice that had been investigated, and the evidence from these papers constantly reported a negative association between mowing intensity and various aspects of plant diversity. Similarly, reduced mowing intensity appeared to favour invertebrate diversity, yet many studies also found mixed associations as well as variations across taxonomic groups. The few studies on chemical input showed a negative association between the frequency of use of herbicides/pesticides/insecticides and the diversity of plants, invertebrates, and birds. Nuanced findings, including a non-linear association between maintenance intensity and biodiversity, and temporal/geographical differences, are discussed in this paper. This review offers insights for the development of biodiversity-friendly management strategies, highlighting existing research gaps and the need for further research concerning the maintenance-biodiversity link in UGSs. [ABSTRACT FROM AUTHOR]

Biodiversity control experiments have demonstrated that higher plant species richness increases plant production and soil organic carbon (SOC) stocks. However, although microbial necromass C constitutes a substantial and stable component of SOC, the effect of species richness on microbial necromass C accumulation remains unclear, especially concerning the presence or absence of legumes. We conducted an 8-year grassland biodiversity experiment to investigate how changes in plant diversity, with or without legumes, affect microbial necromass C and its proportion in SOC. Aboveground and root biomass increased by 254 % and 195 %, respectively, from monoculture plots to those with twelve species. SOC, total nitrogen (N), and microbial biomass C (MBC) all increased with plant species richness, independent of legume presence. The presence of legumes further increased the SOC, total N, MBC, and inorganic N compared to plots without legumes. Microbial necromass C increased by 48.3 % in twelve-species mixtures compared to monocultures; however, the ratio of microbial necromass C to SOC remained stable with increasing species diversity. Notably, the presence of legumes increased both the accumulation of microbial necromass C and its proportion in SOC compared to the absence of legumes at both high and low species diversity levels. This greater accumulation was primarily driven by increased plant productivity and microbial biomass, induced by legume-associated nitrogen fixation. Our findings highlight significant implications for ecosystem management: maintaining high levels of plant species diversity, particularly in conjunction with legumes, can increase microbial necromass C and enhance soil C sequestration. [Display omitted] • Microbial necromass C and soil organic C increased with plant species richness. • Plant production and microbial biomass increased with symbiotic N fixation by legumes. • Legume presence increased microbial necromass C compared to its absence at different species diversity levels. • Microbial necromass contributes to SOC were higher in the presence of legumes compared to their absence. [ABSTRACT FROM AUTHOR]

Grasslands support various ecological functions, such as climate regulation, soil and water conservation, carbon turnover, and nutrient cycling. However, nearly a half of global grasslands have been degraded to varying degrees, especially on the Qinghai–Tibet Plateau (QTP), an extremely fragile ecosystem. As a primary measure of grassland restoration, fertilization largely affects soil aggregate size distribution (ASD) and particle size distribution (PSD). Fractal theory provides a powerful tool for analysis and characterization of soil ASD and PSD. However, our current understanding of soil ASD and PSD responses to fertilization remains limited. Therefore, this study investigated the response of soil structure and fertility to long-term fertilization in alpine grasslands on the QTP based on fractal theory. Long-term fertilization caused significant changes in soil ASD, which varied depending on fertilization practice, particularly in the topsoil (0–5 cm). Soil texture, which is influenced by soil parent material, exhibited a continuous vertical distribution along the depth and was not altered by fertilization. In addition, the results further confirmed that large microaggregates with specific pore structures contributed more to soil organic carbon (SOC) sequestration than did other size aggregates. The generalized dimension spectra showed varying increases (6.27–34.93 %) in the complexity or fineness (ΔD) of the soil PSD after fertilization. Capacity dimension (D 0) decreased significantly with NP addition and was correlated strongly with plant species diversity and richness, whereas the information dimension (D 1), D 1 /D 0 , and correlation dimension (D 2) exhibited significant correlations with soil nutrients. During long-term fertilization, soil texture dominated the vertical distribution of the soil erodibility factor, and characteristic microaggregates were the key factors influencing change in soil microstructural stability. Overall, the findings highlight that selection of appropriate fertilization methods (single or combined applications) is vital for regulation and improvement of soil structure and fertility in alpine grasslands. • Long-term fertilization caused significant changes in soil aggregate size distribution. • Increased complexity (ΔD) of soil particle size distribution after fertilization. • Large microaggregates (0.05–0.25 mm) contributed more to SOC sequestration. • Soil texture dominated the vertical distribution of the soil erodibility factor. • Characteristic microaggregates were the key factors for soil microstructure stability. [ABSTRACT FROM AUTHOR]

• Based on UAV images, the effectiveness and noise susceptibility of 18 vegetation indices in estimating wetland plant species diversity were evaluated. • Revealed that MTCI and NDREI are the most powerful vegetation indices in predicting wetland plant species diversity. • It demonstrates the complementarity of the mean and standard deviation of vegetation indices in predicting plant species diversity. Prior research on vegetation indices (VIs) to estimate species diversity in forest and grassland ecosystems has shown limitations when applied to wetland ecosystems due to their complex structure. Consequently, the predictive capacity of various VIs for wetland plant species diversity and their susceptibility to image noise remain largely unknown. To address these gaps, we utilized high-resolution multispectral images from Unmanned Aerial Vehicles (UAV) and field survey data in marsh wetlands. Various VIs and species diversity indices were computed, and univariate and multiple linear regression models were employed to assess predictive ability of the mean, standard deviation, and coefficient of variation of VIs for wetland plant species diversity. Results revealed that MTCI and NDREI exhibited the highest predictive ability for plant species diversity both before and after masking image noise. While most VIs generally improved in predictive ability after masking image noise, their susceptibility to it varied. MTCI, NDREI, SAVI, MSAVI, and MSAVI2 were less affected by image noise, with minimal changes in predictive ability before and after masking image noise. Conversely, CTVI, NDVI, and other VIs showed high susceptibility to image noise, with significant improvement in predictive ability after masking. ANOVA results indicated that integrating the mean and standard deviation of VIs into models significantly enhanced estimates of species diversity, highlighting their complementarity in predicting species diversity. These findings provide valuable insights into the predictive ability of different VIs for wetland plant species diversity, guiding selection of optimal VIs for predicting plant species diversity at broader scales in the future. [ABSTRACT FROM AUTHOR]

Grasslands restored on arable land often retain high residual nutrients, modified soil biota, and lower plant species diversity. Establishment of rare plant species with complex multitrophic interactions, typical of undisturbed nutrient-poor environments, may be hindered by the absence of interacting organisms. We hypothesised that the addition of a mycorrhizal symbiont improves the seed germination of orchids that crucially depend on fungi. We focused on grasslands restored on arable land 1–15 years ago featuring residual mineral nutrients and low organic matter contents compared to semi-natural grasslands and on four orchid species differing in the level of mycorrhizal specificity: high – Anacamptis pyramidalis and Orchis mascula – and low – Platanthera bifolia and Gymnadenia conopsea. Five fungal isolates obtained from non-green underground mycorrhizal orchid seedlings (protocorms) or adults' roots were tested for orchid-fungus compatibility under conditions in vitro. Orchid seeds inserted in retrievable seed packets were subsequently co-introduced with selected fungal isolates grown either on agar or sterilized hay into the soil of nine restored grasslands and incubated for twelve months. The identity of mycorrhizal fungi in retrieved protocorms was verified by molecular methods. The isolates that supported protocorm establishment in vitro enabled also protocorm formation in situ , but success rates differed among orchid species. While mycorrhizal specialists produced most protocorms after inoculation, the mycorrhizal generalists took advantage of naturally occurring fungi and produced some protocorms both in inoculated and uninoculated treatments. We showed that the addition of mycorrhizal fungi enhanced protocorm formation regardless of the modified soil environment, especially in mycorrhizal specialist orchids. This method may help to restore populations of native orchid species in their former distribution ranges, including farming-altered habitats. [ABSTRACT FROM AUTHOR]

Fencing is an important and common grassland management strategy for restoring areas degraded by grazing. However, experimental evidence regarding the differences between the effects of short-term and long-term fencing on grassland structure remains insufficient, and the mechanisms by which fencing influences plant diversity and community structure are not yet fully understood. A long-term fencing experiment was conducted in a Tibetan meadow. We investigated Hill diversity, aboveground net primary productivity (ANPP), plant community height, species richness, and the biomass and height of four plant functional groups (including grasses, forbs, legumes, and sedges) after 1, 2, 3, and 13 years of fencing. This allowed us to compare the differing impacts of fencing on diversity and community structure over time. Additionally, we collected data on environmental factors such as soil compaction, soil moisture, soil nutrients, and plant litter biomass to elucidate the effects of fencing on plant communities. Our results indicated that short-term fencing increased Hill diversity within plant communities. Conversely, long-term fencing significantly decreased Hill diversity in alpine meadows. Furthermore, fencing reduced aboveground net primary productivity across all four assessment periods. Plant diversity exhibited a positive correlation with soil compaction and soil moisture, but a negative correlation with community height, litter biomass, and litter height. Fencing primarily influenced the diversity of litter biomass, community height, and soil nitrate nitrogen content across all biotic and abiotic factors. Our findings demonstrate that the effects of short-term and long-term fencing on plant communities differ markedly. Long-term fencing can adversely affect plant communities through litter accumulation and alterations in soil physical properties; therefore, the duration of fencing must be considered in grassland restoration efforts. • Short-term fencing elevated plant species diversity, but long-term fencing decreased plant diversity. • Fencing decreased ANPP in both short and long-term fencing. • Plant litter and soil compaction mediated the negative effect of long-term fencing on plant species diversity [ABSTRACT FROM AUTHOR]

Nitrogen (N) is essential for net primary production, with much of the required N in terrestrial ecosystems derived from recycling via litter decomposition. The diversity and identity of plant species and decomposer organisms affect N cycling during litter decomposition, yet the generality and magnitude of these effects remain uncertain. To fill this gap, a decomposition experiment with four leaf litter species that differed widely in initial litter quality was conducted including single species and all possible multispecies mixtures, with and without microarthropods access across a broad latitudinal gradient covering four major forest biomes of the Northern Hemisphere. The results showed that leaf litter N dynamics (both N loss and N immobilization) in single species treatments depended primarily on litter species identity and the local environmental context. We found strong mixture effects, that overall tended to increase N loss and to reduce 15N transfer. The relative mixture effects on N dynamics differed among forest biomes, but were little affected by the other factors we manipulated. The N loss of individual litter species in mixtures not only depended on litter identity and soil microarthropod access, but also on forest biomes; while 15N transfer depended strongly on litter mixing, independently of litter species richness or composition of the mixtures. Litter N dynamics were mainly driven by a small subset of litter traits, regardless of species richness and microarthropod access. Overall, our results highlight that litter mixture strongly affects N dynamics during decomposition, with the mixture effects predominantly varying among forest biomes but little with litter identity, diversity and microarthropod access. To improve predictions on how changes in tree species composition and diversity may impact nutrient dynamics in forest ecosystems in face of increasing N deposition, interactions between litter and soil but also within litter mixtures need closer attention. • Litter mixture strongly affects both N loss and N immobilization. • Mixture effects overall tended to increase N loss and to reduce N immobilization. • N dynamics primarily depended on litter species identity and forest biome. • N dynamics were mainly driven by a small subset of litter traits across biomes. [ABSTRACT FROM AUTHOR]

In the Alps, grasslands have been the basis for European mountain farming systems for centuries, but nowadays agro-pastoral abandonment is among the major threats to their conservation. Grazing and mowing interruption favours the spread of coarse plants, such as the tall grass Brachypodium rupestre , which negatively impacts grassland agroecosystem functions and ultimately leads to grassland degradation. Practices such as nutrient addition (i.e. fertilisation) and biomass removal (i.e. mowing) have been successfully applied in several mountain environments to reverse the degradation process and restore the original species composition. However, in the Alps, experiments combining both practices have been scarce so far. We hypothesised that the benefits of fertilisation and mowing on the species composition of a B. rupestre encroached grassland could be maximised by coupling fertilisation (120 kg ha−1 N – 80 kg ha−1 P 2 O 5 – 80 kg ha−1 K 2 O) and mowing. Treatments were carried out yearly over ten years and data were collected throughout the entire period to study the changes in agronomic performances (i.e. pastoral value and abundance of meso-eutrophic grassland species cover), plant diversity (i.e. species richness and effective number of species), and botanical composition. Fertiliser addition effectively enhanced meso-eutrophic grassland species after five years but did not affect either B. rupestre cover or the sward pastoral value. Instead, it slightly reduced the dry grassland species cover, which is considered of conservation interest, and the plant diversity. Mowing successfully reduced B. rupestre presence after five years while maintaining the initial dry grassland species cover and overall species diversity as well. However, it did not improve either meso-eutrophic grassland species cover or the pastoral value. The combination of fertilisation and mowing showed the most promising results. It was able to decrease B. rupestre cover (- 80 %) in the short term while increasing meso-eutrophic grassland species cover (+ 300 %) and the pastoral value (+ 6.5), without negatively impacting dry grassland species cover and plant diversity. According to our long-term study, combining biomass removal by mowing and nutrient addition by fertilisation can be a suitable strategy to achieve agronomic performances and habitat conservation targets, and successfully restore degraded mountain grasslands in the Alps. • We studied a pasture of Alps encroached by the coarse grass Brachypodium rupestre. • Fertilisation, mowing, and their combination were applied for ten years. • Fertilisation enhanced good quality plants but did not alleviate the encroachment. • Mowing reduced B. rupestre cover but did not enhance grassland pastoral value. • The combined treatment fostered the agronomic value while preserving biodiversity. [ABSTRACT FROM AUTHOR]

Exploring the impact factors associated with biodiversity and the relationship between them has always been a concerned issue in recent years. However, the previous research mostly focus on theoretical layer. Accordingly, the relationship between landscape pattern and biodiversity is to be analyzed in this research. The landscape pattern determines the function and ecological process of the landscape, and affects the species flow, information flow and energy flow in the landscape. Land use patterns has inevitably left an impact on the landscape pattern. Landscape pattern determines the function and ecological process of landscape and thus plays a significant role in biodiversity. East Dongting Lake National Nature Reserve is taken as the research object of the paper, and the remote sensing image data of three different time periods are collected, including 2000, 2010 and 2020. With an interpretation of the vegetation landscape pattern changes inside the protected area to collect and analyze the vegetation coverage. By comparing landscape patterns and the dynamic changes of land use in different periods of time, the correlation between landscape pattern characteristics and regional biodiversity is to be analyzed. Research shows: (1) From 2000 to 2020, the vegetation coverage of East Dongting Lake increased, but the landscape shape, scale, diversity and uniformity index decreased to varying degrees. (2) At the class level of landscape type, the relationship between landscape index and biodiversity is different. A complex relationship between farmland landscape and biodiversity. There is a significant positive correlation between the index of grassland landscape type and the index of regional biodiversity. (3) The correlation analysis results at the landscape level show that the landscape characteristic index is positively correlated with the regional biodiversity index. The grassland landscape in the area is the main habitat of biological species. At the same time, as the main grain producing area, the impact of farmland landscape cannot be ignored. This study has certain theoretical guiding significance for the protection and management of biodiversity in the region in terms of maintaining landscape pattern in particular the grassland landscape area and increasing vegetation coverage in the process of land use. [Display omitted] • Land use change trend shows the increase of woodland and decrease of unused land. (81 characters). • High vegetation coverage area of East Dongting Lake increased 15.13 km2 in 2000–2020. (85 characters). • Grassland landscape index has positive correlation with regional biodiversity index. (84 characters). • Landscape shape index is strongly positive correlated with Gleason index, R is 0.607. (85 characters). [ABSTRACT FROM AUTHOR]

• Increased tree species richness boosts soil N mineralization. • Leaf N and soil moisture predict soil N mineralization. • Monoculture forests display a negative link between N mineralization and tree productivity. • No significant correlation existed between N mineralization and tree productivity in mixed forests. • Tree species diversity can mitigate N limitation in subtropical forests. Forest ecosystems are facing declining plant species diversity. However, the effects of reduced tree species diversity on soil nutrient supply and tree productivity remain poorly understood. We conducted a biodiversity-ecosystem function experiment with a range of subtropical tree species richness (1, 4, 8, 16, and 32) to investigate the impacts of tree species diversity on soil net nitrogen (N) mineralization rates and its regulation on tree productivity in a young subtropical forest experiment. Our findings indicate a log-linear trend between soil net N mineralization rates and tree species richness, potentially suggesting an improvement in soil N supply capacity with greater species richness. Leaf N content, soil water content and peroxidase enzyme activity were identified as primary positive predictors influencing soil net N mineralization rates. In monoculture forests, soil net N mineralization rates were negatively correlated with litter production and tree basal area, while no such correlation was observed in mixed forests. This implies that soil net N mineralization rates play a critical role in tree productivity for monoculture forests. Together, these results provide strong evidence that the rate of decrease in soil nutrient supply capacity potential accelerates with the loss of tree species diversity in young tree communities, and highlights the importance of increasing tree species diversity to mitigate nutrient limitations. Therefore, preserving tree species diversity is crucial for the future functionality of ecosystems amidst global biodiversity loss. [ABSTRACT FROM AUTHOR]

Numerous researchers have endeavored to discover a general explanation for elevational diversity gradients, but we remain unclear whether similar diversity patterns and driving factors exist for the same life-forms along different elevational gradients within the same region. In the Ili Valley of the Central Asia Biodiversity Hotspot, we selected four elevational gradients with similar species pools and evolutionary histories to assess the factors influencing of elevational diversity pattern. Our findings indicate distinct patterns of species diversity for the same life-forms along the four elevational gradients within the same region. The species richness and abundance of woody plants are primarily controlled by climate-based factors (i.e., minimum temperature, temperature seasonality, mean annual precipitation, and potential evapotranspiration) along four elevational diversity gradients in the Ili Valley, while the species richness and abundance of herbaceous plants are primarily influenced by both climate and soil nutrients (i.e., soil organic carbon). In conclusion, climate is an important driver of species diversity for woody plants, and that the driving mechanisms of herbaceous plant diversity along elevational gradients should consider both climate and soil nutrients. • The distinct patterns of species diversity along the four elevational gradients for the same life-forms in the Ili Valley. • Climate is an important driver of species diversity for woody plants. • The driving mechanisms of herbaceous plant diversity along elevational gradients should consider both climate and soil nutrients. [ABSTRACT FROM AUTHOR]

Livestock production in southern South America heavily relies on extensive native grasslands, characterized by high plant species diversity, which makes estimating forage digestibility and intake by ruminants in this pastoral ecosystem challenging. Therefore, the aim of this study was to develop regression models to establish the relationship between total faecal nitrogen excretion (FNe) and organic matter (OM) intake, and faecal nitrogen content (FNc) and OM digestibility in sheep fed multi-species native forage. In a completely randomized design, 16 Corriedale sheep averaging 44 kg of body weight (BW) were housed in metabolism cages and received forage in amounts of 15, 20, 25 g of dry matter per kg of BW or ad libitum. During the spring of 2019 and the summer of 2020, four measurement periods were carried out. The sheep had 5 days of adaptation to the metabolism cage, 10 days to adapt to the treatments of amounts of forage offered, and 5 days for intake and digestibility measurements. The forage was harvested once a day, and then the fresh forage was offered at two different times, 8 and 17 h. A linear regression model was developed to estimate OM intake in sheep fed multi-species native forage based on the FNe [Intake (g OM/sheep/day) = 107.7 + 101.5 × FNe]. An exponential regression model was developed to estimate forage OM digestibility in sheep based on the FNc (Digestibility = 0.31411e0.02995 × FNc). In conclusion, our findings highlight that the OM intake can be precisely estimated using FNe and a reasonably precise estimation of the forage OM digestibility can be reached by assessing FNc in sheep fed a multi-species native forage from the Rio de la Plata region in South America. • Multi-species native forages were used to study intake and digestibility in sheep • Faecal N was used as a marker to estimate intake and digestibility in sheep fed native forages. • Regression models were performed to predict intake and digestibility in sheep fed native forages. • Faecal N excretion can be used precisely to estimate intake in sheep fed native forages. • Digestibility can be estimated with reasonable precision by assessing the faecal N content in sheep fed native forages. [ABSTRACT FROM AUTHOR]

The increasing deer population has significantly altered the forest ecosystems. Deer browsing affects not only plant species diversity and composition but also other organisms indirectly, along with soil properties. However, the effects of deer grazing on the soil microbial community and the underlying mechanisms have not been well understood. To assess these effects, we compared the understory environment and soil microbial community inside and outside fences at Mt. Shiraga, where severe soil environmental degradation has occurred due to sika deer grazing. We selected 20 Fagus trees inhabiting areas within and outside the fences with similar topological features. Eleven environmental variables and both soil prokaryotic and fungal communities were compared between samples inside and outside the fences. The area inside the fence had significantly higher dwarf bamboo density and soil carbon (C) and nitrogen (N) content, whereas soils outside the fences had higher pH and bulk density. The diversity index of the fungal community, in terms of the number of amplicon sequence variants, inside the fence was higher than that outside, whereas that of the prokaryotic community did not differ between fences. Both prokaryotic and fungal communities differed between inside and outside fences. The prokaryotic community changed with the soil C/N ratio, and the relative abundance of oligotrophic bacteria increased with decreasing soil C/N ratio. The fungal community also changed with soil pH and dwarf bamboo density, with the relative abundances of symbiotrophic fungi and ectomycorrhizae increasing with increasing soil pH. Comparative analyses between inside and outside fence samples might provide information on soil microbial community changes with the changes in soil properties after deer grazing. • Microbial community with soil properties inside and outside fence were compared. • Inside deer fences, understory dwarf bamboo was found alongside soil nutrients. • Soil C/N ratio affected prokaryotes, and soil pH and dwarf bamboo density affected fungi. • Ectomycorrhizal fungi decreased with increasing soil pH, not by fence installation. • Fence installation affected microbial community via soil property changes. [ABSTRACT FROM AUTHOR]

• Warming does not alter aboveground net primary productivity (ANPP) regardless of grassland degradation, but degradation reduces it. • Warming does not alter net ecosystem carbon change (NEE) regardless of grassland degradation. • There are no interactions between warming and degraded grassland on plant composition, ANPP and NEE. • Warming neither accelerates degradation of alpine grasslands nor promotes restoration of degraded alpine grasslands. It is still debated whether warming induces degradation of alpine grasslands and whether warming accelerates the restoration of degraded alpine grasslands. Here we conducted a warming experiment using open top chambers to explore warming effects on plant composition and diversity, aboveground net primary productivity (ANPP) and net ecosystem carbon exchange (NEE) in alpine grassland at three degradation levels (i.e., no-degradation, moderate degradation and desertification) on the Tibetan Plateau from 2014 to 2016. There were no interactive effects between warming and degradation level on the variables measured in our study, except for plant diversity. Warming enhanced plant species diversity at no-degradation sites but had no significant influence on species diversity at sites of moderate degradation and desertification. Generally, warming alone had no significant effects on ANPP or seasonal average NEE during the experimental period, but its effect on them varied with year. In addition, compared with non-degraded sites, heavy degradation decreased ANPP by 35.8%, 44.2% and 63.8%, and reduced NEE by 71.8%, 63.4% and 70.3% in 2014, 2015 and 2016, respectively. The effects of moderate degradation on ANPP and NEE varied with year, enhancing ANPP by 37.3% and 37.7% in 2015 and 2016, but moderate degradation had no remarkable influence on seasonal average NEE compared with non-degraded sites. These results suggest that warming neither accelerates degradation of alpine grasslands nor promotes restoration of degraded alpine grasslands on the Tibetan Plateau. [ABSTRACT FROM AUTHOR]

Forests in Ethiopian highlands have been degraded by diverse anthropogenic factors. In response to this, exclosures have been implemented widely as a vegetation restoration strategy for decades. However, studies that show the potential of exclosures in restoring degraded forests in the study area are scarce. Here, we evaluate the woody species diversity, structural attributes, and responses of functional traits in dry Afromontane forests of northern-eastern highlands of Ethiopia under varying forest exclosure ages. A systematic transect sampling method was employed to gather woody species data from four treatments, including open woodland (OWL), exclosure for ten years (EX10), twenty years (EX20), and thirty years (EX30). Within each treatment, we sampled from two slope orientations. Diversity, stand attributes and functional traits data were collected from 185 plots, each with a size of 20 m × 20 m, at all study sites. Smaller nested plots were established to account for seedlings and saplings. We used Generalized Linear Mixed-effect Models (GLMMs) to test variation in diversity metrics between slope orientations and forest exclosure ages. Non-metric multidimensional scaling (NMDS) and one-way permutational multivariate analysis of variance (PERMANOVA) were performed to visualize the difference in species composition among forest exclosure ages. Sixty-one woody species belonging to 34 families were identified from OWL, EX10, EX20 and EX30. Species richness (0D) indicated a considerable increasing trend with increasing forest exclosure ages. Shannon diversity index (1D) showed significant differences (p<0.001) among exclosure ages and slope orientations, while evenness and inverse Simpson (2D) were only different within exclosure ages and slope orientations, respectively. EX30 had the highest Shannon diversity (1D), while OWL had the lowest. The study found that species composition increased with forest exclosure ages, with higher species similarity observed between EX20 and EX30. Our results showed that exclosure treatment substantially (p<0.05) increased woody species density, basal area, seedling density, and sapling density. However, the variation in diameter at breast height (DBH) among exclosure ages was insignificant. According to the DBH distribution, an inverse-J shape pattern was found across all forest exclosure ages, indicating a healthy regeneration status. Juniperus procera and Dodonaea angustifolia had high importance values (IVI) in exclosure areas. Despite their insignificant variation, most functional traits showed an increasing trend with increasing exclosure ages. In general, the study highlights that exclosures can enhance ecosystem restoration in degraded landscapes and thus offers crucial insights for forest management in other areas by prioritizing biodiversity hotspots and threatened species. • Exclosure ages on woody diversity, structure and functional traits were quantified. • Exclosure ages were shown to enhance richness, diversity and stand attributes. • North-facing slope affected diversity, while the south-facing slope influenced evenness. • We found no significant variation in functional traits with increasing exclosure ages. • Expert-based forest management strategies are crucial for ensuring ecosystem benefits. [ABSTRACT FROM AUTHOR]

• Ten undescribed C 40 /C 30 /C 20 terpenoids were isolated from Pseudotsuga forrestii. • 17,13- Friedo -lanostane 1 has a rare skeleton with an α, β -unsaturated spirolactone. • Tetraterpene 3 is a unique intermolecular [4 + 2] triterpene-monoterpene hybrid. • Compounds 9 and 35 showed significant inhibitory effects against the DRAK2 enzyme. • A molecular docking study was performed to provide an insight into the binding site. Glycolipid metabolism disorders (GLMDs) have been reported to be involved in dysfunctions of a few key enzymes such as ATP-citrate lyase (ACL) and death-associated protein kinase (DAPK)-related apoptosis inducing protein kinase-2 (DRAK2). Exploring new and effective small molecule ligands for these enzymes, natural products are expected to have the advantage over synthesized compounds. In our preceding work, a number of C 50 terpenoids with bioactivities against ACL have been found from Pseudotsuga forrestii (a 'vulnerable' Yunnan Douglas fir) by the guidance of an LC-MS/MS-based molecular ion networking strategy. The combination of the rest portions of the EtOAc fraction from this precious plant sample did not predict any C 50 compounds, but it was detected to be rich in C 40 /C 30 /C 20 terpenoids and preliminarily exhibited DRAK2 inhibition. In this follow-up study, ten undescribed terpenoids (1 − 10) and 25 structurally related known compounds were further isolated and characterized. The new structures and their absolute configurations were determined by spectroscopic methods and/or X-ray diffraction analyses. 7,13- Friedo -lanostanes 1 and 2 feature intriguing skeletons with an unusual α, β -unsaturated spirolactone unit formed between C-13 and C-23 via oxygen-bridge or with an 8(14→13)- abeo moiety. Triterpene-monoterpene hybrid 3 could be regarded as a unique tetraterpene formed by intermolecular [4 + 2] Diels-Alder cycloaddition between a rearranged lanostane (dienophile) and a β -myrcene (diene). Methyl 15-methoxy-8,11,13-abietatrien-18-yl-succinate (9) and 3-oxo-24(E)-lanosta-8,24-dien-26-oic acid (35) were confirmed to have DRAK2 inhibitory effects with IC 50 values of 6.6 and 4.1 μ M, respectively. A molecular docking study disclosed alternative H-bonds/interacting amino acid residues between compounds 9 / 35 and the DRAK2 enzyme when comparing with those of the synthesized inhibitors reported in literature. The above findings could support the important role of protecting plant species diversity in support of chemical diversity and potential sources of new therapeutic agents for the treatment of GLMDS. [Display omitted] [ABSTRACT FROM AUTHOR]

European semi-natural grasslands are hotspots for biodiversity and important for the provisioning of multiple ecosystem services, but their extent has declined considerably during the past century. Increasing demands for agricultural and forest biomass risk causing further loss of grasslands, raising concern about a goal conflict between climate mitigation and biodiversity conservation. This study focused on the loss of semi-natural grasslands in a mixed farm-forest landscape in southern Sweden by comparing plant diversity in grasslands with continuous grazing regimes to recently abandoned grasslands, improved grasslands (sown leys), and afforested grasslands. Compared to actively grazed grasslands, grasslands where grazing had been abandoned showed a lower plant species richness and fewer plant species of conservation concern, but similar species composition. In contrast, both improved and afforested grasslands showed >50 % lower species richness than abandoned and grazed grasslands, with profoundly different species composition. The dissimilarity in plant diversity between sites was primarily driven by the replacement of species (turnover), and trait-based analyses indicated that environmental filtering of light, management, and nutrient requirements of plants shaped the community differences. Furthermore, an increased cover of semi-natural grassland around the sites positively related to plant species richness and diversity, while an increased cropland coverage around the sites showed a negative relationship. Our results emphasize the importance of integrated land-use strategies that prioritize biodiversity conservation in mixed farm-forest landscapes, such as restoration of semi-natural grasslands and strategic planning of biomass production to avoid serious biodiversity losses. [Display omitted] • Little is known of the ecological consequences of using abandoned land for energy biomass production. • We compared the impact on plant diversity from three LUC scenarios for SNGs: abandonment, improvement, and afforestation. • All scenarios showed lower plant species richness and fewer species of conservation concern compared to managed SNGs. • The biomass scenarios had the lowest diversity with distinctly alterered species compositions. • In a growing bioeconomy, the biodiversity implications of biomass production on abandoned land need to be considered. [ABSTRACT FROM AUTHOR]

Large herbivores are considered a natural and important determinant for high biodiversity in woodland habitats and have been increasingly reintroduced to nature areas across Europe with the aim of re-establishing natural processes to promote and protect biodiversity. One of the herbivore species playing an increasing role in ecological restoration initiatives is the European bison – the largest extant terrestrial mammal in Europe. However, despite numerous reintroductions of bison for biodiversity purposes, the empirical evidence for their impact is highly limited. Using permanent plots, we investigated the impact of European bison on ground vegetation in forest habitats over a period of eight years. The bison increased the species richness of vascular plants, though mainly to the benefit of graminoids. The effect varied, however, among forest types, with the strongest effect in oak forests with dense and abundant ground vegetation while beech forests characterized by full canopy cover were unaffected. Bison also benefitted bryophytes, which increased in abundance, indicating a generally altered competitive environment with reduced dominance. These results thus provide some of the first empirical evidence, indicating that European bison can promote plant species diversity in forest habitats, by removal of plant biomass, zoochorous seed dispersal, and creation of microhabitat. We thus suggest that introduction of European bison to mixed light woodlands can be a good strategy, benefitting both biodiversity and the conservation of the threatened herbivore species itself. • European bison increase species richness of vascular plants in forest. • Bison grazing increases abundance of bryophytes. • Effects of bison grazing vary among forest habitat types. • The strongest effect is in habitats with dense and abundant ground vegetation. [ABSTRACT FROM AUTHOR]

• The anthropogenic pastures in the humid tropical Andes form a small-scale mosaic of grassland types characterized by different mostly exotic grass species. • Due to varying soil properties, individual pasture types are associated with certain geomorphological features of the sloping terrain. • Today, the fast growing African Golden Millet (Setaria sphacelata) is increasingly used to (re)plant the pastures, irrespective of the terrain. • Having investigated the pasture quality over two decades we recommend to plant Golden Millet only on the better soils of the lower slopes of the undulating terrain. Pastoralism is the main land use in the humid tropical Andes of South America. Wide areas of mountain rainforest have been cleared for gaining pastureland. Due to the lack of indigenous useful grasses in the pristine forests, mainly exotic grass species have been used for establishing the pastures. In the Ecuadorian Andes, Axonopus compressus, Melinis minutiflora, Pennisetum clandestinum and Holcus lanatus are common pasture grass species. Their preference for certain microsites resulted in a mosaic of different pasture types, which reflect the differing ecological conditions on the undulating terrain of the mountain slopes. During the last decades, however, another exotic grass species, Setaria sphacelata has widely been introduced which, because of its fast growth on some of the sites could successfully suppress the formerly dominant plant species. With respect to the changing microclimate and cattle stocking rates the present study explored, whether planting Setaria is the best option for the common low-input type of pasture farming in these tropical mountains. In a study over twenty years, the development of four main pasture types, dominated by the above-mentioned grass species was investigated in areas with and without Setaria , and their topographical occurrence on the sloping terrain was analyzed. On forty-eight plots a pairwise (with or without Setaria) comparison of species composition and diversity, biomass production, forage quality and soil properties was performed. Although Setaria grows faster than the other grass species, its productivity was only higher on flat terrain. The nutritive value of the Setaria plots was at best equivalent to that of the former pastures, while species richness was consistently lower. Our results suggest the maintenance of a terrain-adapted diversification of the pastures and in particular the use of Setaria only on flat terrain. [ABSTRACT FROM AUTHOR]

● Hakea drupacea reduces the diversity of native plant species probably through the effect of litter production and canopy cover ● Uninvaded sites had higher numbers of native plant species compared to invaded sites ● Litter depth was significantly higher in invaded sites compared to uninvaded and cleared sites ● Active removal of H. drupacea restored native species in previously invaded sites The influence of invasive alien plants on plant community structure and above ground biomass in their novel range is poorly understood, as the magnitude and direction of these effects are often species and ecosystem specific. Here we compared community metrices of native plants and soil properties between study sites invaded by Hakea drupacea , uninvaded sites and cleared sites (sites formerly invaded by H. drupacea). A total of 129 plant species belonging to 75 genera were recorded across all study sites. Invasive Acacia saligna, A. longifolia, A. cyclops (Fabaceae) and Leptospermum laevigatum (Myrtaceae) co-occurred with H. drupacea in the invaded sites. Overall plant species richness, which constituted higher number of native plant species, was recorded in uninvaded sites compared to invaded and cleared sites. Plant species composition was similar between uninvaded and cleared sites, but species composition recorded in uninvaded and cleared sites were significantly different from species composition recorded at invaded sites. Litter depth was significantly higher in invaded sites compared to uninvaded and cleared sites. Hakea drupacea did not affect soil properties in invaded sites. Here we show that H. drupacea probably reduces the diversity of native plant species especially in invaded sites probably through the effect of litter production and canopy cover, pointing to a beneficial effect of removal of H. drupacea. We encourage active restoration of sites invaded by H. drupacea at early stages of invasion before the plants become established and suppress the growth of native species. [ABSTRACT FROM AUTHOR]

• Species richness increased plant potassium (K) and magnesium (Mg) concentrations • Species richness increased nitrogen (N), phosphorus (P), K, Mg, calcium (Ca) pools • Species richness and the presence of O. javanica increased plant biomass • The presence of Oenanthe javanica increased plant N, P concentrations and pools • The presence of Reineckia carne decreased plant N, K, Ca, and Mg pools and biomass Plant species diversity affects plant nutrient pools, however, previous studies have not considered plant nutrient concentrations and biomass simultaneously. In this study, we conducted an experimental system with 90 microcosms simulating constructed wetlands (CWs). Four species were selected to set up a plant species richness gradient (1, 2, 3, 4 species) and fifteen species compositions. The plant biomass, plant N, phosphorus (P), potassium (K), calcium (Ca), and magnesium (Mg) concentrations and pools were analyzed. Results showed that, (1) plant species richness increased plant biomass, and the presence of Oenanthe javanica e increased while the presence of Reineckia carnea decreased plant biomass; (2) plant species richness only increased plant K and Mg concentrations of the communities and plant Mg concentration of the species, and the presence of O. Javanica increased while the presence of R. Japonicus decreased plant N and P concentrations of the communities; (3) plant species richness increased plant N, P, K, Ca, and Mg pools, and the presence of O. Javanica increased while the presence of R. Carnea decreased plant N, P, K, Ca and Mg pools; (4) the four-species mixture produced more biomass and nutrient pools than the corresponding highest specific species monocultures. In case the plant uptake can remove nutrients from CWs through harvesting, the results suggest that both nutrient concentrations and biomass must be considered when evaluating the accumulation of nutrients. Assembling plant communities with high species richness (four species) or certain species (such as O. Javanica) is recommended to remove more nutrients from CWs through harvesting. [ABSTRACT FROM AUTHOR]

Revealing the relationship between plants and root-associated fungi is very important in understanding diversity maintenance and community assembly in ecosystems. However, the community assembly of root-associated fungi of focal plant species along a subtropical plant species diversity gradient is less documented. Here, we examined root-associated fungal communities associated with five ectomycorrhizal (EM) plant species (Betula luminifera, Castanea henryi, Castanopsis fargesii, C. sclerophylla , and Quercus serrate) in a Chinese subtropical woody plant species diversity (1, 2, 4, 8, 16 and 24 species) experiment, using paired-end Illumina MiSeq sequencing of the ITS2 region. In total, we detected 1933 root-associated fungal operational taxonomic units (OTUs) at a 97% sequence similarity level. Plant identity had a significant effect on total and saprotrophic fungal OTU richness, but plant species diversity level had a significant effect on saprotrophic and pathogenic fungal OTU richness. The community composition of total, saprotrophic and EM fungi was structured by plant identity and plant species diversity level. However, the community composition of pathogenic fungi was only shaped by plant identity. This study highlights that plant identity has a stronger effect on the root-associated fungal community than plant species diversity level in a diverse subtropical forest ecosystem. [ABSTRACT FROM AUTHOR]

Urban green spaces are often subject to intensive management and therefore only provide habitat for very few plant and animal species. Many studies have already proven that less intensive management of near-natural grassland habitats can increase species diversity, for example of butterflies. However, there is still a lack of knowledge as to what extent less intensive management of urban green spaces can promote urban butterfly diversity. Therefore, we examined parameters that determine the number of butterfly species in less maintained or even abandoned urban green spaces. We expected butterfly species richness and observation numbers to be affected by different management regimes. Butterfly surveys were carried out on 56 sites in the city of Hannover, Germany, in three consecutive years. The sites were subject to different management regimes. We explored parameters such as area size, the diversity of nectar plant species and habitat diversity for each site. A total of 34 species were recorded, with a minimum of 0 and a maximum of 17 species per site and year. The extreme drought and heat in 2018 clearly influenced the results of our study and this was reflected in massive decreases of observation numbers for some species. Less intensive management showed preferable effects in comparison to intensive management, but area size and nectar plants were more important factors influencing butterfly species richness and number of observations. Our results suggest that site parameters such as area size, nectar plant species richness or number of habitat types had stronger influences on butterflies than variations of extensive management. We conclude that less intensive urban green space management for good butterfly habitats is not a question of grazing, mowing or temporary abandonment, but instead must aim to increase nectar plant and habitat diversity. [ABSTRACT FROM AUTHOR]

• High-elevation environments in the Himalayas are stressful for plant life. • Himalayan endemic Berberis angulosa is a nurse shrub that facilitates beneficiary species. • Facilitation by Berberis shrubs promotes plant diversity, and protects high-value and threatened medicinal species. • The nurse shrub plays a critical role in structuring plant communities in high-elevation Himalayas. Facilitation is a global phenomenon that occurs when one species promotes the growth, survival, or reproduction of another species, mostly in stressful environments. However, the importance of facilitation by shrubs in maintaining plant community diversity is not well evaluated in the Himalayas, especially for the richness and conservation of medicinal and human-valued species. Therefore, we aimed to explore the facilitative role of a dwarf shrub species, Berberis angulosa , in maintaining plant composition and richness of human-valued species in the Langtang valley of Nepal's Himalayas. We censused plant species in open patches and beneath Berberis during monsoon and post-monsoon (dry) seasons at three elevations. Total species richness and richness of human-valued species were significantly higher inside the Berberis canopy than in gaps; the former being 39% and the latter 46% greater under shrubs than in open sites. Facilitation by Berberis shrubs promoted plant community diversity irrespective of season and elevation; however, higher differences in mean species richness for both total plant species and human-valued species during the dry season and at high elevation indicated increased facilitation intensity under more stressful conditions. The facilitative effect of Berberis shrubs increased, combining both seasons, overall plant diversity by 19% (total=105), and human-valued species by 16% (total=56). Our results show the importance of facilitation by nurse shrubs in structuring plant communities and protecting medicinal and socio-ecologically important plants, thus enriching ecosystem services in the Himalayas. These results suggest nurse plant species should be incorporated into conservation policies and management strategies for effective biodiversity conservation and sustainability, especially in the face of climate change. [ABSTRACT FROM AUTHOR]

Changes in the hydrological regime can significantly alter the structure, function, and biodiversity of wetlands. Soil seed banks (SSB) are crucial for maintaining the species diversity and plant regeneration in wetlands. Although the relationships between plant communities and hydrological conditions have been widely studied, the intrinsic mechanisms driving SSB dynamics are poorly understood because a tendency to neglect the influence of hydrological regimes on SSB. Field survey and germination experiments were conducted to determine the structure and composition of the aboveground plant community and SSB of Carex hummock wetlands under different hydrological regimes in the Western Songnen Plain of China and investigated the driving process of the hydrologic regime on SSB dynamics. The results showed that, compared with those under flooded (surface water depth was maintained at 5–10 cm for long-term) and drought (no still water on the soil surface, soil moisture content <65% for about 9–11 months annually) conditions, the values of characteristics of aboveground vegetation (Carex hummock, C. schmidtii population, and plant community) were generally higher under moist (no still water on the soil surface, soil moisture content >65% for about 8–9 months annually) conditions. C. schmidtii is the dominant species of plant community under different hydrological regimes. In response to hydrological regime changes, SSB differed in their density, richness, and diversity, and the soil bulk density and soil water content explained 41.8% and 6.8% of SSB structural variation, respectively. A non-metric multidimensional scaling analysis indicated the significant differences between the species composition of SSB and aboveground vegetation under different hydrological regimes in Carex hummock wetlands. Based on the structural equation model, it was found that the variation in the hydrological regime directly affected the hummock morphology, plant community density, and SSB density. Additionally, it indirectly influenced the density of aboveground vegetation by directly associating with the density of SSB. This study demonstrates that the hydrological regime exerts an influence on the species composition of SSB, thereby governing the role of SSB in the process of plant community regeneration within Carex hummock wetlands. These findings enhance our understanding of the effects of hydrological regimes on SSB and provide crucial information for the restoring of degraded Carex hummock wetlands. • Density and richness of soil seed bank(SSB) were regulated by hydrologic regime; • Hydrologic regime affects the similarity between aboveground plants and SSB; • Hydrologic regime directly and indirectly affects the soil seed bank in wetlands. • SSB is an important resource for implementing soil bioengineering. [ABSTRACT FROM AUTHOR]

Green infrastructure, specifically rain gardens, are increasingly used to manage urban runoff. Rain gardens vary in design and composition for a mix of aesthetic and functional reasons. Due to this variability, key performance drivers are hard to identify. This study evaluated 100 vegetated rain gardens in Lancaster, PA across seasons to determine which aspects of rain garden design impact performance. Gardens varied in size, slope, plant composition, planting density, and soil characteristics. There were significant seasonal differences in both performance (as measured by infiltration) and garden characteristics. Soil water content, compaction, and electrical conductivity along with plant species diversity significantly impacted infiltration. Certain plant species - Vernonia baldwinii (Ironweed), Nepeta cataria (Catmint), Itea virginica (Virginia Sweetspire), Rudbeckia sp. (Coneflower), and Eragrostis pectinacea (Purple Lovegrass) were present in high abundance and found to be drivers of performance. The results of this study demonstrate the diversity of factors that influence rain garden performance and highlight the importance of aligning soil and plant characteristics with specific outcome goals. [ABSTRACT FROM AUTHOR]

• The plant diversity and composition of the traditional agroecosystems of arid southern Morocco corresponds to the agricultural practice and the associated habitat conditions. • Traditional agroecosystems promote a high level of plant species and community diversity, both at the field and landscape levels. • The plant communities of traditional arid agroecosystems are dominated by indigenous species and host a number of regional and national endemic species, as well as some rare and endangered species. • The studied arable plant communities in the Mediterranean-Saharan transition zone in southern Morocco represent the southernmost occurrences of Mediterranean-type agroecosystems known so far. In the arid landscapes of South Morocco's Saharan fringe, traditional agroecosystems stand out for their rich diversity of segetal vegetation. This study examines the segetal flora of these unique agroecosystems, investigating their richness, community characteristics and composition. We collected 155 relevés in fields located in the Guelmim province comprising three agroecosystem types: Oases, terraced and floodplain fields (faïd). We found 221 vascular plant species including seven regional endemics and one nationally very rare species. Using TWINSPAN, we identified three plant communities, each restricted to a specific agroecosystem type, displaying differences in species composition, floristic status, life-form and biogeographical spectra. Oasis vegetation had the highest overall number of species, terraced fields had the highest diversity, and therophytes were dominant across all communities, with faïds being the most therophyte-rich. The pan-Mediterranean chorotype dominated all three community types. Apophytes dominated, particularly in faïd and terraced fields, surpassing oasis fields rich in ruderals. We found that traditional cereal agroecosystems in southern Morocco harbor species-rich segetal plant communities created by habitat-based land-use systems. Our results highlight the significance of agricultural practices and local abiotic factors in shaping the agroecosystems, which are adapted to arid environments and sensitive to environmental and social changes. [ABSTRACT FROM AUTHOR]

An investigation on the secondary metabolites from a rice culture broth of the endophytic fungus Neurospora terricola HDF-Br-2 derived from the vulnerable conifer Pseudotsuga gaussenii led to the isolation and characterization of 34 structurally diverse polyketides (1 – 34). Seven of them are previously undescribed, including five unprecedented dihydropyran-containing (terricoxanthones A–E, 1 – 5 , resp.) and one rare tetrahydrofuran-containing (terricoxanthone F, 6) dimeric xanthones. The structures were elucidated by spectroscopic methods and single-crystal X-ray diffraction analyses. Terricoxanthones each were obtained as a racemic mixture. Their plausible biosynthetic relationships were briefly proposed. Compounds 6 , aspergillusone A (8), and alatinone (27) displayed considerable inhibition against Candida albicans with MIC values of 8–16 μg/mL. 4-Hydroxyvertixanthone (12) and 27 exhibited significant inhibitory activities against Staphylococcus aureus , with MIC values of 4–8 μg/mL. Furthermore, compounds 8 and 27 could disrupt biofilm of S. aureus and C. albicans at 128 μg/mL. The findings not only extend the skeletons of xanthone dimers and contribute to the diversity of metabolites of endophytes associated with the endangered Chinese conifer P. gaussenii , but could further reveal the important role of protecting plant species diversity in support of chemical diversity and potential sources of new therapeutics. Five unprecedented dihydropyran-containing and one undescribed tetrahydrofuran-containing dimeric xanthones were isolated and characterized from the endophytic fungus Neurospora terricola HDF-Br-2 associated with the endangered conifer Pseudotsuga gaussenii. The dimers reported herein each were obtained as a racemic mixture. Some isolated xanthones exhibited antimicrobial and antibiofilm effects against Staphylococcus aureus and Candida albicans. [Display omitted] • Six undescribed dimeric xanthones were obtained from an endophytic Neurospora sp. • N. terricola HDF-Br-2 was isolated from the endangered conifer Pseudotsuga gaussenii. • (±)-Terricoxanthones A–E are unprecedented dihydropyran-containing dimeric xanthones. • The xanthone dimers reported herein each were obtained as a racemic mixture. • Some isolated xanthones exhibited antibacterial and antibiofilm effects. [ABSTRACT FROM AUTHOR]

Urban stormwater ponds (SPs) are important for flood protection strategies in areas with heavily sealed soils as they mitigate the negative effects of floods. SPs with temporary waters (TWs) are only flooded when water levels or surface runoffs are high, while SPs with permanent waters (PWs) contain a permanently flooded area. In urban areas, SPs are important secondary habitats for plants and animals as natural aquatic and semi-aquatic habitats are often destroyed during urbanization. In 2017, a large survey on vascular plant diversity of 80 SPs was conducted in the city of Hamburg (Germany). The aim of the study was to analyze plant diversity of TWs and PWs and to identify relationships between plant diversity and different urbanization parameters. In total, 30% of the plant species pool of Hamburg was found in the surveyed SPs representing 0.03% of the total area of Hamburg. We found significant differences in the number and proportion of aquatic, threatened and non-native species between the shoreline and bottom of TWs and PWs. The number and proportion of aquatic species was positively correlated with the proportion of urban green and negatively correlated with the degree of soil sealing in the direct surrounding of SPs. For the proportion of threatened species in the bottom of TWs, a positive relationship was found with the proportion of urban green in the surrounding of SPs. For the number and proportion of non-native species in the shoreline of SPs, negative relationships were found with the proportion of urban green and the number of different habitat types in the surrounding of SPs. Further, a positive relationship with the degree of soil sealing was identified. Our results highlight the nature conservation value of urban SPs for plants and showed the negative effects of urbanization on several plant species groups. • Diverse plant species assemblages were found in the stormwater ponds (SPs) in Hamburg. • 30% of the plant species of Hamburg were found on 0.03% of its total area. • No clear patterns for the influence of urbanization on plant diversity were found. • Patterns differed between the hydrological conditions and zones of SPs. [ABSTRACT FROM AUTHOR]

Half a century ago, Janzen and Connell hypothesized that the high tree species diversity in tropical forests is maintained by specialized natural enemies. Along with other mechanisms, these can cause conspecific negative density dependence (CNDD) and thus maintain species diversity. Numerous studies have measured proxies of CNDD worldwide, but doubt about its relative importance remains. We find ample evidence for CNDD in local populations, but methodological limitations make it difficult to assess if CNDD scales up to control community diversity and thereby local and global biodiversity patterns. A combination of more robust statistical methods, new study designs, and eco-evolutionary models are needed to provide a more definite evaluation of the importance of CNDD for geographic variation in plant species diversity. Stabilizing conspecific negative density dependence (CNDD) is a classical explanation for diversity maintenance in species-rich ecosystems, particularly in tropical forests. Fifty years after Janzen and Connell popularized this idea, a plethora of empirical evidence suggests that CNDD can be found at all latitudes and for many tree species. On closer inspection, however, it is still unclear if locally measured density effects are indeed stabilizing community dynamics and, moreover, if they have a causal effect on large-scale diversity and abundance patterns, such as the latitudinal diversity gradient. More robust and comparable CNDD estimates are needed, coupled with a theoretical research program that aims at understanding the role of CNDD for coexistence in stochastic multispecies communities as well as macroecological and macroevolutionary diversity patterns. [ABSTRACT FROM AUTHOR]

The objective of this experiment was to identify and characterize the bovine milk proteome within the skim milk fraction and milk fat globule membrane (MFGM)-associated fraction from 16 organically certified lactating Jersey cows after a short term of grazing pastures with or without annual forage crops (AFC). Cows were offered a partial mixed ration (∼60% of dry matter intake) and approximately 40% of their total dry matter intake as herbage. Eight cows were offered a cool-season grass–legume herbage (GLH), which included orchardgrass (Dactylis glomerata), timothy (Phleum pratense), Kentucky bluegrass (Poa pratensis), and white clover (Trifolium repens). The other 8 cows were offered the same GLH strip-tilled with the AFC, including oat (Avena sativa), millet (Pennisetum glaucum), teff (Eragrostis tef), buckwheat (Fagopyrum esculentum), and chickling vetch (Lathyrus sativus). Milk samples were collected from each cow during a.m. and p.m. milkings on d 19 to 21 of grazing, and composite milk samples per cow were analyzed for (1) the high-abundance milk protein profile, (2) the skim milk low-abundance protein-enriched proteome, and (3) the MFGM proteome. Of the 443 proteins identified in the skim and MFGM proteomes, 433 were included in statistical analysis, including 68 proteins identified in the skim milk fraction and 365 in the MFGM-associated fraction. Analysis of the skim and MFGM proteomes encompassed unique gene ontology profiles and proportions of functional classifications. In response to diet, α S1 -casein as well as 8 low-abundance proteins were present in higher concentration or abundance in milk from cows grazing the GLH strip-tilled with the AFC compared with milk from cows grazing GLH, suggesting that even short-term grazing of pastures including some AFC may affect the milk proteome. [ABSTRACT FROM AUTHOR]

Calcareous grasslands are rich in biodiversity and thus receive much attention in nature conservation. In such grasslands, the formation of moss layers is perceived as a management problem. However, its impacts on the community level are complex, as not only inhibition but also facilitation of vascular plant recruitment occur. Possible filters of recruitment are shading by mosses, isolation from soil resources and the resulting desiccation. To understand how seed size and shape moderate moss effects, a combined glasshouse and field experiment was conducted in southern Germany. Seeds of 14 species from calcareous grasslands were sown either on top or underneath a moss layer, or on bare soil without moss. We determined the total number of emerged and established seedlings, i.e. the ones that survived until the end of the experiment. Both measures were reduced for most species sown on moss, while mortality was slightly enhanced by moss presence. Seed size explained a significant proportion of the moss effects on plant recruitment. Inhibitive effects on recruitment increased with seed size when seeds were placed on top of moss. When germinating underneath moss, the effect on emergence changed from negative in small-seeded plant species to positive in large-seeded species, but this effect was insignificant for establishment. The positive response in large seeds was probably due to their higher moisture requirements for imbibition, and lower dependency on light for germination. However, moss-seed-interactions were not affected by seed shape. Seedling establishment of plants with large seeds strongly depended on their initial position in moss, while small-seeded species showed no effect. Hence, moss layers constitute a selective recruitment filter by modifying seed penetration and hence germination conditions. This effect could increase beta diversity of vascular plant species in calcareous grasslands, and thus conservation should aim at intermediate and patchy moss abundance. [ABSTRACT FROM AUTHOR]

Extensively managed semi-natural grasslands represent species-rich habitats and therefore play a key role for the maintenance of biodiversity in agricultural areas. In marginal and poorly accessible areas, the traditional management of grassland is frequently abandoned, which leads to the spread of forest. In Southern Switzerland, terraced vineyards (a special grassland type) and terraced grasslands are part of the cultural heritage and local biodiversity hotspots. Yet, many of them are overgrown by forest. In the past years, several abandoned terraced vineyards and grasslands have been restored by removing the forest, rebuilding the walls and re-introducing the traditional management. We examined restoration success by assessing plant species richness, diversity and species composition in both the aboveground vegetation and soil seed bank in (1) restored, (2) abandoned for 25–50 years, and (3) permanently used areas of six terraced vineyards and six terraced grasslands. Plant species richness and diversity were reduced and species composition altered in the aboveground vegetation of abandoned vineyards and grasslands compared to the permanently used and restored ones. However, species richness, Shannon-diversity and species composition of the aboveground vegetation did not differ between restored and permanently used areas, indicating a successful restoration of the vegetation 10–15 years after restoration. In abandoned vineyards, species richness of plants emerging from the soil seed bank was slightly higher than in permanently used and restored vineyards. No difference in seedling species richness was found between abandoned, permanently used and restored terraced grasslands. Our results showed that the soil seed bank played a minor role for the re-establishment of the above-ground vegetation. We assume that the large species pool in the surroundings and the presence of dispersal vectors are essential for the successful passive restoration of abandoned grassland in this region. [ABSTRACT FROM AUTHOR]

[Display omitted] • Landscape changes across the European Alps were mapped since the mid-19th century. • Socio-economic and natural drivers were ranked according to their importance. • Forests, intensive crops and settlements increased, but traditionally used types declined. • Provisioning Ecosystem Services (ES) have generally increased. • In favourable regions, plant diversity, regulating and cultural ES decreased. Landscape appearance is controlled by a range of different environmental and human-induced factors, although there is still a lack of knowledge about the significance of individual factors. Our goal was to identify the factors that were significant for landscape change in the European Alps and to rank them according to their importance. Therefore, we mapped landscape change with a standardized survey methodology in six typical socio-ecological regions with strongly differing socio-economic and natural conditions. The results clearly showed that significant landscape change has taken place in all regions over the last 150–200 years, affecting biodiversity and ecosystem services (ES). In general, the areas used for agriculture have decreased in all regions, particularly the traditionally used forms (−72.7 % to −6.9 %). The greatest decrease took place in the high elevation, agriculturally unfavourable areas (-72.6 % to −41.6 %) and regions with weak economic conditions (−62.9 % to −20.9 %). The forest has spread on a large scale on the abandoned land in economically strong regions but also settlements and monotone and intensively used cultures. As a consequence of the landscape changes, plant species diversity declined, particularly in favourable regions with a good site and economic conditions (−62.7 % to −7.2 %), while it decreased far less in the economically unfavourable regions (−20.1 % to −0.7 %). Regulation & maintenance and cultural ESs have also decreased, whereas provisioning ES generally increased. Our results also showed that the regional framework conditions play a much more important role in landscape development in the European Alps than national frameworks. Higher "green subsidies" reduced the intensification trend in agriculture, but also led to increased abandonment. In addition, the landscape also remained more diverse, biodiversity declined less and many ecosystem services increased. This demonstrates that interpreting historical landscape dynamics and analysing impacts on ecosystem services can be a valuable guide to sustainable decision-making processes. [ABSTRACT FROM AUTHOR]

Describing the diversity of Brazilian plant species, as well as the wide variety in the associated pollen grains, is crucial to understanding their evolution and ensuring effective conservation. The accurate identification of pollen is key to successful pollen studies and the consistent paleoecological interpretation of past vegetation changes. Pollen analysts usually identify plant taxa from reference collections built from herbaria material. In Brazil, pollen atlases primarily focus on three main vegetation domains, namely, the Amazon Forest, the Atlantic Forest, and the Cerrado, while information about Caatinga pollen taxa is dispersed across multiple studies; this significantly impedes efforts to further develop palynological research. To address this gap, we built a palynological atlas for the state of Piauí which is covered by the biomes Caatinga and Cerrado along with their transitional zones. These domains encompass various vegetation types, including dense shrubland, grassland, palm swamp formation, riverine forest, seasonal deciduous and semi-deciduous forests, as well as valley-side marshes. We collected flower buds from the Herbarium Prisco Bezerra (EAC) at the Federal University of Ceará and extracted the pollen grains for the pollen reference slides. The atlas comprises 398 species from 99 families, with the most represented families being Asteraceae, Bignoniaceae, Euphorbiaceae, Fabaceae, Lamiaceae, Malvaceae, Malpighiaceae, and Rubiaceae. Each taxa is presented with a description of the pollen grain, a photo showing polar and equatorial views, and ecological information as life form (liana/scandent/vine, herb, subshrub, shrub or tree), substrate, and vegetation type to support further studies. • We present a reference pollen catalog for northeastern Brazil. • We used flower buds from the Herbarium Prisco Bezerra (EAC), Ceará, Brazil. • The catalog describes 388 genera from 99 families. • The catalog describes 51 taxa for the first time. [ABSTRACT FROM AUTHOR]

• The PSF and tree diversity interactively affected subtropical tree seedling growth. • Unlike AM tree, EcM tree PSF changed from positive to negative with increasing tree species richness. • Morphological and physiological plant traits explain the PSF changes. • Pathogenic fungal diversity and co-occurrence complexity are critical for altering the PSF of AM and EcM tree. Plant-soil feedback (PSF) is an important driver of plant species coexistence and diversity maintenance. However, it remains unclear how changes in PSF due to decline in tree species richness influence the performance of arbuscular mycorrhizal (AM) and ectomycorrhizal (EcM) tree species. A PSF experiment was established with eight target tree species (four AM and four EcM tree species) based on a subtropical forest Biodiversity-Ecosystem Functioning Experimental in China (BEF-China) platform, where soil inocula were collected beneath the canopy of target tree species individuals growing in monoculture and eight tree-species mixture plots. We hypothesized that the negative PSF strength of AM tree species would be stronger in monocultures than that in eight tree-species mixtures, resulting in better performance in highly diverse plant communities, whereas EcM tree species would benefit less from tree species richness. However, the results showed consistent PSFs of AM tree species regardless of tree species richness. In contrast, EcM tree species experienced a change from positive in monocultures to negative PSF in eight tree-species mixtures, influencing the performance of EcM tree seedlings. With high concern of the cascading effects of tree species richness on PSFs via modulating soil fungal communities, we revealed that the alterations in EcM fungal abundance, putatively pathogenic fungal diversity, and fungal co-occurrence network complexity mirrored those of PSF associated with EcM tree species, showing the changes from positive in monocultures to negative feedback in eight tree-species mixtures. Our findings highlight the differential PSFs exhibited by AM and EcM tree species in response to tree species richness, and provide insight into the potential role of fungal functional guilds and co-occurrence network complexity in shaping the PSFs of them. [ABSTRACT FROM AUTHOR]

Agricultural landscapes play a crucial role in global carbon sequestration and biodiversity conservation. The presence of trees outside forests has been recognized as a significant carbon pool, but it is crucial to acknowledge that these trees serve purposes beyond being a carbon sink. This study focuses on integrating border trees and home gardens as distinct land use classes in Indonesian Javanese agricultural land to assess their impact on carbon stock potential and biodiversity connections. The objective is to classify and quantify the tree composition of these classes, estimate their carbon stock potential, analyze plant species diversity, and identify the ecological connections between home gardens and field borders. To achieve this, high-resolution multispectral and Synthetic Aperture Radar images were used from four sampling areas covering 100 km2 each in Lamongan and Malang districts, East Java, Indonesia, for land cover/land use mapping. The land use function method was used to identify border trees and home gardens as separate land use classes. Carbon stock potential was estimated based on tree cover composition, while plant species diversity was analyzed through field surveys and farmer focus group discussions. Crops with border trees cover approximately 28% to 48% of the cropland area in the study sites, while home gardens represent about 74% to 85% of the settlement area. This suggests a potential to double tree presence in these sites by adopting border trees and home gardens practices across the entire area. The median tree cover ratio was around 27% for border trees and 33% for home gardens. This stratification approach identified 31% to 50% more carbon stock compared to calculations using standard classes. Furthermore, home gardens and border trees show a positive correlation with species richness, indicating their role as keepers of biodiversity. Therefore, home gardens and border trees could serve as a sustainability indicator for agricultural land in the Javanese farm system. This research contributes to sustainable agricultural practices and climate change mitigation. The stratification approach of identifying border trees and home gardens offers a cost-effective approach for the better computation of carbon stock and can lead to effective land use policies and conservation measures that promote ecological resilience. The study provides valuable insights for similar agricultural contexts worldwide, guiding efforts toward a more sustainable agricultural future. [Display omitted] • Trees outside forests constitute significant carbon pools and play diverse ecological roles, not just carbon sinks. • Proposed classification categories of "home gardens" & "border trees" can enhance our understanding of their functions. • Multispectral and Synthetic Aperture Radar images were used for the analysis of land use and land cover. • This stratification approach identifies 31–50% more carbon stock than the conventional approach. • The home gardens and border trees area have a positive correlation with the number of species richness. [ABSTRACT FROM AUTHOR]

Wildfires in forested ecosystems are increasing in severity and extent. The adaptations many plants have acquired in response to their natural fire regime may not be sufficient to allow some species to persist. This could impact the forest understorey and its seed bank, which are vital reservoirs of biodiversity, and forest resilience in the face of global change. We present a case study of the montane forests of south-eastern Australia, an area subjected to an increase in frequency and severity of fires. We utilise field surveys and a soil seed bank germination study to investigate if short-interval, high-severity wildfires affect the understorey diversity in montane forests, and if the extant vegetation and the soil seed bank exhibit contrasting responses. We consider species diversity and plant functional traits to explore plant diversity in long unburned sites, and sites with one, two or three short-interval, high-severity fires in the past 25 years. With increasing fire frequency, we found a decrease in total species richness, Shannon's diversity, and the richness of resprouters in the soil seed bank, contrasting a lack of response in the extant vegetation. Increased fire frequency shifted the species composition and the frequency of plant functional groups of both extant vegetation and soil seed bank towards a decrease in clonal resprouters and increase in grasses and other upright herbs. The frequency of wind-dispersed perennials and short-lived seeders and exotics increased sharply following single high severity burn, particularly in the soil seed bank, and remained elevated relative to long unburnt with subsequent fire. The combined species (extant vegetation plus soil seed bank) pool mirrored shifts in the frequency of functional groups in extant vegetation and soil seed bank. These findings highlight the importance of considering the soil seed bank when examining the effects of fire on fire-prone forests. Although a lack of response in the extant vegetation may be a buffering effect of the soil seed bank, the shift in the frequency of plant functional groups in the combined species pool suggests this cannot be maintained indefinitely. The increase in frequency and abundance of species characteristic of early successional states has implications for increased flammability and potential positive feedbacks between past fire and future fire, especially in a warming and drying climate. These shifts were independent of the fire response strategy of eucalypt canopy species raising significant questions of whether artificial re-seeding programs should extend beyond the current focus on obligate seeding forests and an obligate seeding tree. • Soil seed bank plant species richness and diversity (H') decreases with increasing frequency of high-severity fire. • Extant vegetation richness and diversity remained stable with increasing fire frequency. • Shift in frequency and abundance of species to those characteristic of early successional states. • Shifts in understorey species independent of fire response of overstorey eucalypts. • Implications for the focus of artificial re-seedings programs. [ABSTRACT FROM AUTHOR]

• Regional climatic indicators explain plant species diversity distribution better than means. • Regional climatic indicators effectively reflect patterns of plant family and genus diversity. • At a regional (county-level) scale in Inner Mongolia, the degree of plant diversity explained by climatic factors increases with decreasing plant taxonomic rank. Climate factors have a major influence on biodiversity patterns have often used their mean values to reflect the distribution of different organisms, reducing the faceted information of the study unit to point information, a situation that may affect the accuracy of the study results. However, there has been a lack of systematic and comprehensive discussion on regional climatic indicators and their selection. To address this, we evaluated plant distribution and meteorological data from 88 banners and counties in Inner Mongolia considering five regional climatic indicators that reflect the state of climate factors, heterogeneity, and total resources in each sampling unit. Additionally, we compared and analyzed the advantages of the regional climatic indicators over mean climate indicators to determine the dominant climate factors driving the diversity patterns of plant families, genera, and species. Our results showed that the regional climatic indicators were better than the mean values at reflecting the diversity patterns of plant families and genera. In Inner Mongolia, plant species diversity patterns were mainly influenced by total precipitation and temperature heterogeneity indicators; and concurrently, the correlation between plant family and genus diversity patterns and regional climatic indicators was also higher than the mean values. The extent to which climate explains the diversity patterns of plants increases with decreasing plant taxonomic rank. The results of this study expand the available selection and use of climate indicators in biodiversity research and deepen the understanding of the effects of climate on plant family diversity patterns in arid and semi-arid regions. Therefore, this study provides new perspectives for the rational selection and accurate use of climate or environmental indicators in biodiversity conservation and restoration research. [ABSTRACT FROM AUTHOR]

• Delineated individual plant communities in tropical forests from airborne LiDAR data. • Investigated the relationships between plant species diversity and canopy structure. • Species richness and Shannon index are accurately predicted by random forest models. • Species richness is primarily determined by return number metrics. • Shannon index is influenced by both return number and canopy height metrics. Tropical forests are widely regarded as the Earth's most important ecosystems, yet they are severely threatened by anthropogenic disturbances. Rapid and extensive monitoring of forest structure and biodiversity is crucial for developing ecologically sound conservation and restoration strategies. Airborne light detection and ranging (LiDAR) can effectively monitor three-dimensional forest canopy structures. Traditionally, LiDAR-based plant diversity estimation has relied on individual tree-based and area-based approaches. However, these approaches face significant challenges in tropical forests due to their complex canopy structures and diverse plant compositions. Therefore, by proposing a novel community-based approach, this study aims to examine the relationship between field-derived biodiversity indices and LiDAR-derived canopy structural metrics of plant communities in a species-rich ForestGEO forest dynamic plot in tropical Hong Kong. Our goal is to determine whether canopy structural metrics extracted from airborne LiDAR data can serve as a robust and efficient alternative for expediting plant diversity monitoring in highly dense and diverse tropical forests. Our results indicate that an integration watershed segmentation technique (for automatic patch-scale plant community delineation), LiDAR-derived canopy structural metrics, and machine learning-based random forest regression analysis can provide accurate predictions of community-based species diversity indices. Among various diversity indices, species richness and the Shannon-Wiener index are most accurately estimated using LiDAR-derived metrics. This study reveals that species richness is predominantly influenced by the existence of multi-layered canopy structures, whereas the Shannon-Wiener index is associated with both multi-layered structures and canopy morphologies. Overall, our findings showcase the immense potential of airborne LiDAR data in advancing the monitoring of structure and biodiversity in dense-canopy and species-rich tropical forests in a spatially explicit manner. [ABSTRACT FROM AUTHOR]