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Knowledge of plant species distribution and abundance at different landscape scales and management‐induced degradation is essential for the conservation, planning, and enhancement of the biodiversity of rangelands. In this study, additive partitioning of species diversity based on contribution diversity was used to analyze the interaction of landscape scale and grazing intensity factor to better understand the distribution of rare and common species. A total of 64 units (quadrats) were sampled by using a nested hierarchical sampling design at three scales of two regions (semi‐arid vs. Mediterranean), four sites, and four quadrats in both exclosure and grazing areas. The regional‐scale species richness (γs(q)) was calculated by the sum of the quadrat (αs(q)) and site (βs(q)) scale contributions to the region. The calculated rank of αs(q) indicated that an abundance of rare species for exclosures (α < 0.05) and the Mediterranean area (α < 0.01) was significantly greater than for grazing and the arid area, respectively. The highly palatable plants significantly correlated (α < 0.01) with the contribution diversity components (alpha/beta) in the exclosure areas but not in grazed areas. Furthermore, of the measured explanatory variables, the electrical conductivity (EC) of the soil was significantly negatively related to γs(q) which shows a sensitivity of rare species to the variable environmental conditions that are related to human influences interacting with soil and climatic conditions. The vegetation attributes of biomass and vegetation cover were significantly (α < 0.01) higher for managed exclosure sites than the grazed areas. The findings of this investigation demonstrate an increasing trend for rare species in managed and better environmental conditions. In conclusion, the protection and restoration of plant species diversity in semi‐arid and Mediterranean grasslands in western Iran are possible through the application of sustainable management practices by decision‐makers and managers. [ABSTRACT FROM AUTHOR]

Habitat heterogeneity caused by topographic variations at the local scale is the environmental basis for the establishment and evolution of biodiversity and biomass patterns. The similarities and distinctions between the effects of microtopographic variables on living wood (LWD) and dead wood (CWD) remain unknown. In the present study, the response mechanisms of biomass and species diversity patterns of living wood (LWD) and coarse woody debris (CWD) to microtopographic parameters were quantified in a warm temperate secondary forest located in Dongling Mountain, China. This quantification was achieved using a generalized additive model on a completely mapped 20-hectare permanent plot. The evaluation of biomass and species diversity of woody plants was carried out by utilizing the total basal area of all individuals and the species richness within each 20 m × 20 m quadrat as a standard. The results indicate that there are notable disparities in the influence of microtopographic elements on the LWD and CWD. In the case of LWD, microtopography accounts for 22.90% of the variation in total basal area, with convexity making a greater relative contribution than elevation, slope, and aspect. Additionally, microtopography explains 46.20% of the variation in species richness, with aspect making a greater relative contribution than elevation, convexity, and slope. Nevertheless, the influence of microtopography on CWD may only account for a deviation of 10.20% in the total basal area and 4.95% in the species richness; aspect and slope have been identified as the primary drivers in this regard. The inclusion of microtopographic factors in the model resulted in a 23.10% increase in the explanatory deviations of LWD biomass and an 8.70% increase in the explanatory deviations of CWD biomass. The findings suggest that topographic considerations have a greater impact on the biomass distribution of LWD compared to that of CWD. Conversely, the biomass of CWD is more influenced by the species richness. The presence of microtopography plays a vital role in determining the spatial distribution of species and biomass at local scales, reflecting the multiple response mechanisms and growth strategies of vegetation in response to redistribution in water, soil, and light. [ABSTRACT FROM AUTHOR]

Woody plants are crucial components of forest ecosystems and play critical roles in regulating community succession and ecosystem function. Studying woody plant diversity and its influencing factors is thus important for understanding and protecting forest ecosystems. Quercus aliena var. acutiserrata is an important deciduous broadleaf species in the warm–temperate forest of central China. Multiple regression and structural equation modelling were used to discuss the effect of biotic and soil factors on tree species diversity across seven relative density gradients of Q. aliena var. acutiserrata trees in this zone. Our results showed that the following: (1) Species diversity showed significant decreasing trends with increasing relative density of Q. aliena var. acutiserrata. (2) As the relative density of the oak tree increased, some biotic factors (canopy density, and mean DBH) and soil factors (Soil SOC, AP, and AK) all showed significantly increasing trends, whereas the DBH variation (CVD) and soil pH displayed decreasing trends. (3) Biotic factor (e.g., mean DBH, CVD, and competition interaction) had strong direct effect on species diversity, and soil factors exerted indirect roles on tree diversity via biotic factors. Our results provide insight into biodiversity protection and scientific management in this warm–temperate natural oak forest. [ABSTRACT FROM AUTHOR]

Plant biodiversity data are prerequisites for the sustainable management of a forest. We used quantitative ecological tools to determine the species composition, diversity (richness and evenness), population structure, distribution patterns, and regeneration status of trees in a Tropical Moist Sal Forest of Eastern Ghats, India. For this purpose, a field inventory was conducted during 2020–2022 in sixteen 1.0 ha forest stands along a human-induced disturbance gradient. A total of 161 species (61 trees, 40 shrubs, 60 herbs) belonging to 77 families and 143 genera were recorded in the 16.0 ha of forest area. The results revealed a significant (p < 0.01) decrease in the tree and shrub species density, basal area, species richness, and diversity along the gradient of disturbance. However, in the case of herbs, the Shannon–Weiner diversity index increased significantly (p < 0.01) with increasing disturbance levels. Irrespective of forest types and disturbance levels, the tree diameter class (10–30 cm) accounted for the highest stem density in the forest. A mixed trend was found in the case of the basal area; the >41 cm diameter class constituted the highest basal area in the Pure Sal Forest while the 10–30 cm class was in the Moist Deciduous Forest without Sal. Tree species richness was found higher in lower diameter classes. Disturbances impacted the distribution pattern of trees; in the Pure Sal Forest, the contagious distribution of trees were 61.54%, 40%, and 12.5% in undisturbed, low-disturbed, and moderately disturbed sites, respectively. The percent of trees showing random and regular distribution increased with the increased level of disturbance in all forest types. The number of tree species having good regeneration decreased with the increased disturbance intensity in all forest types. Frequent grazing, repeated forest fires, and poor soil seed banks at the Moderately Disturbed site were the main reasons for the poor/no regeneration of Pterocarpus marsupium, Adina cordifolia, Terminalia bellerica, and some other economical species. Significant changes in structural attributes of the tree community revealed the impact of human-induced disturbances in the Moist Sal Forests of Eastern Ghats. The disturbance mosaics promoted the growth of many invasive weed species and lianas, depleting the number of valuable species in the forest. This study suggests the adaption of sustainable biodiversity conservation approaches through the active participation of the tribal so that the remnants the Moist Sal Forests of Eastern Ghats can be controlled to prevent further degradation. [ABSTRACT FROM AUTHOR]

Wild ginger (Hedychium gardnerianum) poses a threat to biodiversity conservation because of its high competition for nutrients, water and light. This study aimed at assessing the effects of the H. gardnerianum on native vegetation species in the Bvumba Mountains, Zimbabwe. A purposive random sampling technique was adopted to sample 24 sites. The results show that there was a significant difference between plant species diversity in uninvaded compared to invaded sites with (P < 0.05). The study concluded that there is a need to develop and implement an invasive species management programme for H. gardnerianum for both protected and communal areas before high species losses occur. [ABSTRACT FROM AUTHOR]

Habitat filtering, species interactions and neutral colonization as well as extinction dynamics govern the sequence of community assembly and functional diversity (FD) during primary plant succession. To study the factors that influence changes in FD we here use data on plant seed size, seed numbers and specific leaf area from 107 study plots along a 7 year sequence of primary succession (2005–2011) in a 6 ha German artificial catchment. We show that the temporal variability in functional diversity can be partitioned into the effects of trait expression, species richness and plant cover. We observed a dominant role of species richness and community composition on FD. Trade-offs in the influence of species richness and plant cover tended to decrease the change in FD. Average FD steadily increased during the first 4 years of succession (2005–2008). The degree of annual changes in FD were highly plot specific. Average change in FD was comparatively low during the first 4 years and later high. Soil characteristics and light conditions did not significantly influence the detectable change in functional diversity. We conclude that the high plot-specific spatial variability of the annual changes in FD transformed the initially catchment-wide homogeneous distribution of plant species into a mosaic of very different local plant communities. Our partitioning results also indicate that the successional sequences in FD are in accordance with a hidden Markov series. [ABSTRACT FROM AUTHOR]

Objectives: Pollen is a useful tool for identifying the provenance and complex ecosystems surrounding honey production in Malaysian forests. As native key pollinators in Malaysia, Apis dorsata and Heterotrigona itama forage on various plant/pollen species to collect honey. This study aims to generate a dataset that uncovers the presence of these plant/pollen species and their relative abundance in the honey of A. dorsata and H. itama. The information gathered from this study can be used to determine the geographical and botanical origin and authenticity of the honey produced by these two species. Results: Sequence data were obtained for both A. dorsata and H. itama. The raw sequence data for A. dorsata was 5 Mb, which was assembled into 5 contigs with a size of 6,098,728 bp, an N50 of 15,534, and a GC average of 57.42. Similarly, the raw sequence data for H. itama was 6.3 Mb, which was assembled into 11 contigs with a size of 7,642,048 bp, an N50 of 17,180, and a GC average of 55.38. In the honey sample of A. dorsata, we identified five different plant/pollen species, with only one of the five species exhibiting a relative abundance of less than 1%. For H. itama, we identified seven different plant/pollen species, with only three of the species exhibiting a relative abundance of less than 1%. All of the identified plant species were native to Peninsular Malaysia, especially the East Coast area of Terengganu. Data description: Our data offers valuable insights into honey's geographical and botanical origin and authenticity. Metagenomic studies could help identify the plant species that honeybees forage and provide preliminary data for researchers studying the biological development of A. dorsata and H. itama. The identification of various flowers from the eDNA of honey that are known for their medicinal properties could aid in regional honey with accurate product origin labeling, which is crucial for guaranteeing product authenticity to consumers. [ABSTRACT FROM AUTHOR]

Under the background of global nitrogen deposition, temperate forest ecosystems are suffering increasing threats, and species diversity is gradually decreasing. In this study, nitrogen addition experiments were conducted on Korean pine (Pinus koraiensis) plantations in Northeast China to explore the effect of long‐term nitrogen addition on herb species diversity to test the following hypothesis: long‐term nitrogen addition further reduced plant species diversity by affecting plant growth, which may be due to soil acidification caused by excessive nitrogen addition. Experimental nitrogen addition was conducted from 2014 to 2021, and the nitrogen treatment levels were as follows: N0 (control treatment, 0/(kg N ha−1 year−1)), N20 (low nitrogen treatment, 20/(kg N ha−1 year−1)), N40 (medium nitrogen treatment, 40/(kg N ha−1 year−1)) and N80 (high nitrogen treatment, 80/(kg N ha−1 year−1)). A herb community survey was conducted in the region from 2015 to 2021. The results showed that long‐term nitrogen addition decreased soil pH, changed the species and composition of herbaceous plants, and decreased the species diversity of understory herbaceous plants. With the increase in nitrogen application years, middle‐ and high‐nitrogen treatments significantly reduced the diversity of early‐spring flowering herbs and early‐spring foliating herbs, and their diversity decreased with the decrease in soil pH, indicating that soil acidification caused by long‐term nitrogen addition may lead to the decrease of plant diversity. However, for early‐spring growing herbs, adequate nitrogen addition may promote their growth. Our results show that plants have evolved different life‐history strategies based on their adaptation mechanisms to the environment, and different life‐history strategies have different responses to long‐term nitrogen addition. However, for most plants, long‐term nitrogen application will have a negative impact on the growth and diversity of herbs in temperate forests. [ABSTRACT FROM AUTHOR]

While trait‐based approaches have been effectively leveraged by plant ecologists to advance our understanding of community responses to major global challenges, such as climate change and invasive species, the study of marine macroalgae is still mired in a functional group (FG) framework developed in the 1980s.In this paper, we used predominantly categorical data for 18 macroalgal traits that were accessible in public databases and/or the literature to explore their usefulness in a trait‐based framework for marine macroalgae. Species were clustered into emergent, data‐driven groups using a Gower dissimilarity matrix, then a k‐medoid clustering approach called partitioning around the medoids.We identified 14 emergent groups (EGs) that captured a spectrum of strategies used by different macroalgal species. However, significant 'gaps' in trait space may identify evolutionary constraints to algal adaptive strategies. Multivariate analysis showed how the 18 traits created trait space and drove the clustering. A spectrum of strategies and the influence of multiple traits imply that algal strategies are likely governed by complex multivariate, not bivariate, trade‐offs. Finally, we found that our EGs appeared to reflect multivariate trade‐offs and diverse ecological strategies more than the traditional FG model for macroalgae. We tested the usefulness of our EGs by comparing real‐world spatial distributions of species across habitats with known strong environmental filters to their area occupied in trait space. We found significant separation in trait space and divergent occupancy patterns across global distributions, attachment substrates and elevational zones. These results support the use of categorical data accessible in the literature as a useful step towards developing trait‐based ecology for marine macroalgae.Synthesis. Our findings indicate that readily accessible categorical traits produce emergent FGs that reflect environmental filtering and therefore demonstrate the power of trait‐based approaches over the current FG framework. Furthermore, we posit that categorical traits are a valuable and potentially complementary addition to a newly developing database of continuous traits because they encompass a broader, more globally accessible set of traits. [ABSTRACT FROM AUTHOR]

Semi‐natural grasslands in Western Europe are degrading and declining. Their plant species diversity and associated fauna, such as arthropods, are decreasing fast making restoration crucial.Carabid beetles are an essential link in ecosystem functioning (e.g., through herbivory and predation) and provide important ecosystem services (e.g., pest control). As a diverse group from different trophic levels, they occupy a variety of ecological niches, making them good indicators of restoration success and habitat quality.To study how different aspects of carabid diversity change along a restoration gradient from degraded grasslands to restored semi‐natural Nardus grasslands, we sampled carabid beetles in grasslands in Northern Belgium. We analysed differences in abundance, diversity and community composition and investigated carabid traits potentially influencing carabids' response to grassland restoration.Species richness did not change along the restoration gradient, but number of individuals decreased as grassland restoration time and effort increased and species composition changed, mostly caused by species turnover. As grassland restoration time and effort increased, carabid body size decreased and the proportion of day‐active carabids increased. Predators and habitat generalists were dominant along the entire gradient.Even though the target vegetation was restored, the carabid communities were not, or at least, did not possess yet traits to be expected from a restored community. The landscape in Northern Belgium might be too fragmented for larger species with low dispersal ability to recolonize restored grasslands. However, restored species‐rich grasslands are beneficial for conservation of meadow birds as day‐active beetles thriving in restored grasslands are an important food source. [ABSTRACT FROM AUTHOR]

In total, 28 of the 29 fish species reported from the Lake Kivu basin occur in the littoral zone of the lake, but information about their structure, occurrence, and the habitats affecting their distribution is largely lacking. The lake's inshore area is poorly heterogenous, with rock and macrophyte habitats representing the major habitats. The lack of heterogeneity in the habitats is probably an important factor influencing species richness, abundance, and the association between the species and habitats. We evaluated the fish diversity, abundance, and habitat parameters across 14 sites representing the major habitats of the lake, using data collected between April 2018 and October 2019. We calculated Hull and Jaccard indices and applied uni- and multivariate statistical approaches to the collected data. We identified 18 fish species in the lake. In the north, 17 species were found, with high abundance in rocky sites but low abundance in sandy habitats. In the south, 15 species were reported. We identified 12 species in the Ishungu Basin where the site with rock substrate had high abundance and 13 species in the Bukavu Basin with weak species richness and low abundance across degraded sites. Lamprichthys tanganicanus, a non-native species, was abundant in rocky (north) and macrophyte sites (south). Sand, rock, conductivity, depth, dissolved oxygen, and water transparency were significant parameters that could explain the fish distribution in the north while dissolved oxygen, vegetation cover, depth, and conductivity were significant in the south. A monitoring programme of the fish fauna in Lake Kivu is needed. [ABSTRACT FROM AUTHOR]

Ecological restoration often focuses on short‐term intervention efforts with the goal of creating restored ecosystems that do not require continuous human maintenance. Here, we ask: Do short‐term restoration efforts result in self‐sustaining native assemblages, or do these restored ecosystems require long‐term management to prevent reinvasion of exotic species? We address this question using restored vernal pool wetlands in coastal California. Restoration efforts in vernal pool ecosystems are often hindered because many restored vernal pools exist within a grassland matrix that is highly invaded by exotic annual grasses and forbs. To test whether restored pools experienced reinvasion, we assessed plant species abundance and diversity at varying times after intensive weeding had ceased. The central bottom of pools, where inundation duration is the longest, showed stable or even increasing native cover and no trends in exotic abundance over time. However, exotic cover and richness increased in the upland edges of the pools, where drier conditions allow exotic grasses from the surrounding unrestored grassland to grow. Our findings indicate that edges of restored ecosystems are susceptible to invasion over time, but that this depends on abiotic and biotic conditions within the ecosystem, such as pool shape and landscape matrix, that can potentially be manipulated through initial planning (e.g., constructing circular pools) and long‐term management (e.g., annual weeding). Our findings highlight the importance of ongoing monitoring and adaptive management and support a paradigm shift away from short‐term interventions and toward viewing restoration as a longstanding relationship with the land that may require continuous human management. [ABSTRACT FROM AUTHOR]

Assessments of species diversity and richness are essential to understand present ecological and biodiversity conditions for effective conservation management strategies. Biodiversity indicators determine rangeland health and response to grazing, fire regimes and climate change. This research examined species richness, diversity and composition in a protected mountainous grassland. Two data sets, both collected from a 30 × 30 m plot, with similar species composition and cover were combined. One data set was collected using a 100‐step point survey and the other from a series of 16 plots. A single‐factor analysis of variance was used to test if the mean species richness and diversity of the sites differed across the study area. Species accumulation curves were used to determine the relationship between species richness and the number of sampling units per site. The results from fitting a species–area equation showed that the estimated maximum species richness was slightly greater than the observed species pool in all sites, meaning that the sampling units were not adequate (albeit by small margins) to capture all vascular plant species in the sites. Diversity metrics could, thus, be used to monitor species change within grassland plant communities. [ABSTRACT FROM AUTHOR]

The high diversity of plant species in homegardens contributes to the provision of a range of goods and services, as well as considerably benefiting the environment and boosting ecological sustainability. Despite their importance, homegardens in Malaysia have not been systematically studied. This paper explores the diversity of useful plant species in Malaysian homegardens, as well as their vertical structure. The effect of the size of homegardens and socio-economic variables on the diversity of plants species were also investigated by using Self Organizing Map, a type of machine learning method. In total, 207 species of useful plants distributed among 169 genera and 78 families were recorded. At the species level, Musa paradisiaca L. had the highest frequency, while Euphorbiaceae had the highest at the family level. The vertical structure of homegardens was divided into five distinct layers: herbaceous layer, shrub layer, understory layer, canopy layer and emergent layer. Plant diversity is influenced by the size of homegardens and socioeconomic variables. As the size of the homegardens increased, as such increased the diversity of plant species. Lower-income households and worked in agriculture sectors that rely on homegrown food and medicinal plants are increasing the diversity of plant species in homegardens, highlighting the importance of these agroecosystems as a food security approach. [ABSTRACT FROM AUTHOR]

Context: Recent studies show that geodiversity—the diversity of Earth's landforms, materials, and processes—has a positive relationship with biodiversity at a landscape scale. However, there is a substantial lack of evidence from finer scales, although this knowledge could improve the understanding of biodiversity patterns. Objectives: We investigate whether plot-scale geodiversity and plant species richness (vascular plants, bryophytes, lichens, and total richness) are positively linked in different tundra landscapes. Methods: We collected geodiversity (presence of different geofeatures) and plant species richness data from 165 sites in three distinct regions: isolated low-lying mountain heaths, and in sporadic and continuous mountain heaths and tundra. We used non-metric multidimensional scaling (NMDS) ordination to explore the correlations between the composition of geofeatures and species richness, followed by univariate and multivariate generalized linear models (GLM), to assess whether georichness is important for species richness. Results: Geofeature composition was linked to species richness in all regions, as indicated by NMDS ordination. Both univariate and multivariate GLM models showed statistically significant relationship between species richness and georichness in all studied species richness groups in continuous Arctic-alpine tundra. Additionally, there was a positive link between georichness and lichen richness in isolated boreal mountain tops. Main conclusions: We showed that plot-scale geodiversity has a positive relationship with species richness, yet the effect varies regionally and between species groups. Our study provides strong empirical evidence that geodiversity supports species richness in continuous Arctic-alpine tundra. This information can be used in species richness models but also be applied in biodiversity management and conservation. [ABSTRACT FROM AUTHOR]

In biodiverse forest ecosystems, plant diversity has been reported to increase plant-derived lignin accumulation and soil organic carbon (SOC) storage. However, little is known about the fate of lignin and its degradation dynamics from plant to soil. This process is critical for the formation of SOC, especially in natural forest ecosystems with diverse plant species. This study presents the lignin biomarker characteristics of several common plant species and in mixed litter. The study was conducted in 45 plots along a plant species diversity gradient in a subtropical forest located in southwest China. Our results demonstrate that lignin content and its biochemical characteristics in plant leaves vary among species, while different plant species also alter the content of lignin and its monomeric compounds in the litter. Lignin compounds are gradually disintegrated from plant leaf to litter and then to soil, further indicating that plant-derived lignin from plant sources contributes to the formation and accumulation of forest SOC. These findings provide novel information on the linkage between tree species diversity and lignin accumulation while indicating the role of plant-derived lignin on SOC storage. These results may be useful in predicting forest soil C dynamics in Earth system models. [ABSTRACT FROM AUTHOR]

Grasslands are one of the largest coupled human-nature terrestrial ecosystems on Earth, and severe anthropogenic-induced grassland ecosystem function declines have been reported recently. Understanding factors influencing grassland ecosystem functions is critical for making sustainable management policies. Canopy structure is an important factor influencing plant growth through mediating within-canopy microclimate (e.g., light, water, and wind), and it is found coordinating tightly with plant species diversity to influence forest ecosystem functions. However, the role of canopy structure in regulating grassland ecosystem functions along with plant species diversity has been rarely investigated. Here, we investigated this problem by collecting field data from 170 field plots distributed along an over 2000 km transect across the northern agro-pastoral ecotone of China. Aboveground net primary productivity (ANPP) and resilience, two indicators of grassland ecosystem functions, were measured from field data and satellite remote sensing data. Terrestrial laser scanning data were collected to measure canopy structure (represented by mean height and canopy cover). Our results showed that plant species diversity was positively correlated to canopy structural traits, and negatively correlated to human activity intensity. Canopy structure was a significant indicator for ANPP and resilience, but their correlations were inconsistent under different human activity intensity levels. Compared to plant species diversity, canopy structural traits were better indicators for grassland ecosystem functions, especially for ANPP. Through structure equation modeling analyses, we found that plant species diversity did not have a direct influence on ANPP under human disturbances. Instead, it had a strong indirect effect on ANPP by altering canopy structural traits. As to resilience, plant species diversity had both a direct positive contribution and an indirect contribution through mediating canopy cover. This study highlights that canopy structure is an important intermediate factor regulating grassland diversity-function relationships under human disturbances, which should be included in future grassland monitoring and management.

This article discusses the use of remote sensing technology in biodiversity and ecosystem functioning research. It highlights the importance of understanding the variation of biodiversity across scales and the role of remote sensing in monitoring and predicting ecosystem patterns and processes. The article presents various studies that utilize remote sensing techniques, such as high-resolution mapping, mobile technology, and UAV-based approaches, to observe and manage diverse ecosystems. It also explores the assessment of ecosystem functioning at large scales and the analysis of biodiversity and ecosystem functioning under environmental changes. The findings emphasize the significance of spatial analysis, remote sensing technologies, and tailored conservation strategies for effective ecosystem management. [Extracted from the article]

The article discusses the importance of conservation horticulture in the Caribbean region, which is home to a diverse range of native plant species that are at risk due to hurricanes, development, and limited resources. Botanic gardens in the region are shifting their focus towards conservation and education, and a workshop was held in 2023 to promote the adoption of conservation practices. The workshop had a profound impact and serves as a successful model for future training opportunities. Continued investment in capacity building initiatives is crucial for achieving plant conservation targets and global conservation goals. [Extracted from the article]

Background: Desert steppe, as an ecotone between desert and grassland, has few species and is sensitive to climate change. Climate change alters species diversity and the stability of functional groups, which may positively or negatively affect community stability. However, the response of plant community stability in the desert steppe to experimental warming and increasing precipitation remains largely unexplored. Methods: In a factorial experiment of warming and increasing precipitation for five to seven years (ambient precipitation (P0), ambient precipitation increased by 25% and 50% (P1 and P2), ambient temperature (W0), ambient temperature increased by 2°C and 4°C (W1 and W2)), we estimated the importance value (IV) of four functional groups (perennial grasses, semi-shrubs, perennial forbs and annual herbs), species diversity and community stability. Results: Compared to W0P0, the IV of perennial grasses was reduced by 37.66% in W2P2, whereas the IV of perennial forbs increased by 48.96%. Although increasing precipitation and experimental warming significantly altered species composition, the effect on species diversity was insignificant (P > 0.05). In addition, increasing precipitation and experimental warming had a significant negative impact on community stability. The stability of perennial grasses significantly explained community stability. Conclusion: Our results suggest that the small number of species in desert steppe limits the contribution of species diversity to regulating community stability. By contrast, maintaining high stability of perennial grasses can improve community stability in the desert steppe. [ABSTRACT FROM AUTHOR]

Mutualistic and antagonistic plant–animal interactions differentially contribute to the maintenance of species diversity in ecological communities. Although both seed dispersal and predation by fruit-eating animals are recognized as important drivers of plant population dynamics, the mechanisms underlying how seed dispersers and predators jointly affect plant diversity remain largely unexplored. Based on mediating roles of seed size and species abundance, we investigated the effects of seed dispersal and predation by two sympatric primates (Nomascus concolor and Trachypithecus crepusculus) on local plant recruitment in a subtropical forest of China. Over a 26 month period, we confirmed that these primates were functionally distinct: gibbons were legitimate seed dispersers who dispersed seeds of 44 plant species, while langurs were primarily seed predators who destroyed seeds of 48 plant species. Gibbons dispersed medium-seeded species more effectively than small- and large-seeded species, and dispersed more seeds of rare species than common and dominant species. Langurs showed a similar predation rate across different sizes of seeds, but destroyed a large number of seeds from common species. Due to gut passage effects, gibbons significantly shortened the duration of seed germination for 58% of the dispersed species; however, for 54% of species, seed germination rates were reduced significantly. Our study underlined the contrasting contributions of two primate species to local plant recruitment processes. By dispersing rare species and destroying the seeds of common species, both primates might jointly maintain plant species diversity. To maintain healthy ecosystems, the conservation of mammals that play critical functional roles needs to receive further attention. [ABSTRACT FROM AUTHOR]

Mounds formed by plateau zokors (Eospalax baileyi) in alpine meadows are easily disturbed by livestock. We aimed to reveal the effect of moderate livestock grazing (from October 15 to March 15 of the following year) on plant and soil characteristics of zokor mounds. This study explored the effect of zokor mounds of different ages (2015–2018) on soil nutrient content, soil enzymatic activity, plant diversity, and aboveground biomass (AGB) at grazing and non-grazing sites. Compared with the non-grazing sites, soil organic carbon (SOC), total soil phosphorus, and ratio of SOC to total nitrogen were 16.6%–98.7% higher and soil urease activity was 8.4% and 9.6% higher in 1- and 3-year-old mounds, respectively, at the grazing sites. Grazing significantly increased the plant Pielou index, richness, and Shannon–Wiener diversity index of 4-year-old mounds by 20.7%–52.4%. Partial least squares path modeling showed that plant species diversity was the main factor affecting the plant AGB of mounds at the grazing sites, whereas soil enzyme activity was the primary factor at the non-grazing sites. We propose that moderate grazing increases soil nutrient content and the plant diversity in zokor mounds in alpine meadows, which should be considered in future grassland restoration. [ABSTRACT FROM AUTHOR]

Soil organic matter contributes to productivity in terrestrial ecosystems and contains more carbon than is found in the atmosphere. Yet, there is little understanding of soil organic carbon (SOC) sequestration processes during tropical forest succession, particularly after land abandonment from agriculture practices.Here, we used vegetation and environmental data from two large‐scale surveys covering a total landscape area of 20,000 ha in Southeast Asia to investigate the effects of plant species diversity, functional trait diversity, phylogenetic diversity, above‐ground biomass and environmental factors on SOC sequestration during forest succession.We found that functional trait diversity plays an important role in determining SOC sequestration across successional trajectories. Increases in SOC carbon storage were associated with indirect positive effects of species diversity and succession age via functional trait diversity, but phylogenetic diversity and above‐ground biomass showed no significant relationship with SOC stock. Furthermore, the effects of soil properties and functional trait diversity on SOC carbon storage shift across elevation.Synthesis. Our results suggest that reforestation and restoration management practices that implement a trait‐based approach by combining long‐lived and short‐lived species (conservative and acquisitive traits) to increase plant functional diversity could enhance SOC sequestration for climate change mitigation and adaptation efforts, as well as accelerate recovery of healthy soils. [ABSTRACT FROM AUTHOR]

Tree‐tree competition has been widely studied as a mechanism responsible for maintaining forest plant species diversity. Other common plant types, such as lianas, may influence tree species competition. Previous studies reported the negative effects of lianas on trees; however, variation in susceptibility to lianas among tree species and the species‐specificity of liana species for tree hosts remain unclear. If lianas have species‐specific interactions with trees, based either on tree or liana species identity, then lianas may influence tree‐tree interactions by altering tree species‐specific competitiveness.We surveyed 5676 lianas (DBH ≥ 0.5 cm) and 61,538 trees (DBH ≥ 1 cm) in a 12‐ha subtropical secondary forest plot to assess liana‐tree interactions. We tested variation among the 20 most common tree species in their susceptibility to lianas, including whether light‐demanding and shade‐tolerant tree species differed. We quantified liana‐tree network structure and evaluated the specificity between the 20 most common tree species and the 15 most common liana species. We expected that: (1) tree species would vary in their susceptibility to lianas, and the extent of this variation would be predicted by tree shade‐tolerance; and (2) liana species would have distinct species‐specific interactions with host trees.Tree species differed greatly in their susceptibility to lianas, with some tree species accumulating many more lianas than others. Light‐demanding tree species particularly had greater susceptibility to lianas than shade‐tolerant tree species. Both the liana‐tree network structure and the interaction intensity between the 15 liana species and 20 tree species showed distinct specialization of liana‐tree interactions.Synthesis. Variation in trees species' susceptibility to lianas implies that lianas may alter tree species‐specific competitive abilities by disproportionately affecting some tree species more than others. In contrast to studies in neotropical forests, light‐demanding tree species were more susceptible to lianas than shade‐tolerant tree species, suggesting that lianas could reduce light‐demanding tree performance in this forest. The distinct species specialization between liana and tree species suggests that increases in the relative abundance of liana species, which is occurring in many forests, may alter the tree community composition by reducing the relative abundance of preferred host tree species. [ABSTRACT FROM AUTHOR]

To enable grasslands to serve a larger ecological and service role against the backdrop of climate change and human activity, management is essential following long-term fencing. Using desert grassland that had been fenced for 20 years, we conducted experiments on different mowing frequencies (once, twice, and three times a year) and different amounts of vegetation coverage (mowing removal, mowing, and in situ mulch; and mowing, in situ mulch, and additional coverage) and control (no mowing, no removal, and no cover). In 2021 and mid-August 2022, the aboveground biomass, species diversity, and vegetation cover of each species were assessed, and the impacts of species complementarity and competition on the productivity of the fenced grassland were examined. Our findings revealed several significant outcomes: (1) Two and three times of mowing per year promoted growth and development of annual or biennial plants and increased species diversity of the community. (2) The interaction impact of mowing and covering two and three times a year was the most important, as it encouraged compensatory development of plants, particularly the dominant species, and increased aboveground biomass of the fenced grassland (p < 0.05). (3) The number of complementary species groups was c. 11% lower for mowing and covering than for mowing removal, indicating that the interspecific relationship for the mowing and covering interaction was dominated by competition, which was more beneficial to the increase in community productivity. (4) Lespedeza potaninii Vass. (which dominated the semi-shrubs) and Agropyron mongolicum Keng (which dominated the tufted grasses) exhibited compensatory growth, which alleviated the change of mowing disturbance and precipitation fluctuation on the productivity of this grassland ecosystem. (5) Adding vegetation cover after mowing positively influenced community production but did not significantly impact litter decomposition. Our research provides data support for the sustainable development of long-term fenced desert grasslands. [ABSTRACT FROM AUTHOR]

Aims: Understanding the distribution pattern of biodiversity in fragmented landscapes is important for conserving biodiversity. The mutualistic interaction between mycorrhizal fungi and plants is an important trait influencing ecological processes, such as plant response to environmental conditions; however, we lack a general understanding of how habitat fragmentation differently affects plant diversity of different mycorrhizal types. Methods: The diversity of arbuscular mycorrhizal (AM) and ectomycorrhizal (EcM) plants, including the number of species on islands, the number of species per plot, and the number of individuals per plot, were calculated on 11 islands within a hydroelectric reservoir in China. We tested the influence of island attributes (island area and isolation), abiotic and biotic variables on the diversity of AM and EcM plants. Results: There was a significant positive correlation between island area and species diversity of AM plants, but not EcM plants. After controlling for island attributes, abiotic variables and the diversity of AM fungi significantly affected the diversity of AM plants per plot. The abiotic and biotic variables explained more variance in the number of AM plant species (58%) and number of individuals of AM plants per plot (52%) than EcM plants (less than 20%). The diversity of AM plants but not EcM plants was higher in interior than in edge plots of the islands. Conclusion: The results indicate that the decrease of plant species diversity with habitat loss was probably related to the extinction of AM plants caused by selection of abiotic variables and diversity of AM fungi. [ABSTRACT FROM AUTHOR]

Plant species loss due to eutrophication is a common phenomenon in temperate perennial grasslands. It occurs in a nonrandom fashion and is usually explained by increased competitive size asymmetry between the co‐occurring winner (tall species with optima in productive habitats) and loser species (small‐statured plants typical for unproductive habitats). It remains unclear why nutrient addition decreases diversity in communities consisting of losers only, whereas it has little effect on winner‐only communities. Here, I used the framework of modern coexistence theory to explore fertilization‐driven changes in fitness and niche differences between different combinations of field‐identified winner (W) and loser (L) species. I experimentally estimated competition parameters for plant species pairs constructed from a pool of eight species, including pairs of species from the same (WW, LL) and different species categories (LW) grown for approximately 2 years in control and fertilized conditions. Concurrently, I also followed plant species diversity in mesocosm communities constructed from the same species pool (four‐species communities including winners, losers, or both) exposed to control and nutrient addition. I found that nutrient addition can reduce but, unexpectedly, also promote species coexistence depending on the type of species pairs. Whereas nutrient addition eroded the coexistence of losers with winners, but also with other losers, treatment had the opposite effect on the persistence of winner species. Fertilization induced large fitness differences between species in loser–winner and loser–loser combinations, but had little effect on the fitness differences of species within the winner–winner combination. In addition, the persistence of winner pairs was promoted by larger niche differences compared to loser species, irrespective of soil nutrients. The differences in how nutrient addition modified coexistence at the pairwise level were reflected by differences in the evenness of multispecies communities assembled from the corresponding species categories. These results suggest that the effect of eutrophication on plant species richness cannot simply be explained by an increased competitive asymmetry. To fully understand the effect of fertilization on the diversity of temperate grasslands, interspecific and intraspecific interactions should be explored while considering differences in species' ecological optima. [ABSTRACT FROM AUTHOR]

Amidst urbanization and industrialization in China, abandoned farmland plays a crucial role in safeguarding plant diversity within agricultural landscapes. This study aimed to examine the patterns of seasonal variation in plant diversity within abandoned farmland habitats in the Huang–Huai Plain region. Nonparametric tests were employed to analyze plant species diversity and phylogenetic diversity across seasons. Redundancy analysis and linear regression were conducted to examine the associations between plant species composition, species diversity, phylogenetic diversity, and soil environmental factors. Our results showed that plant species diversity, richness, and phylogenetic diversity were highest in spring, followed by summer, and lowest in autumn. The phylogenetic structure of plant communities demonstrated a tendency to diverge in spring, become random in summer, and cluster in autumn. Soil available potassium and soil organic matter emerged as important factors influencing plant species composition. The content of soil organic matter and ammonium nitrogen level exhibited a significantly positive correlation with the species diversity and phylogenetic diversity of plants. This study underscores the significance of considering seasonal and temporal scales when investigating plant diversity and provides a theoretical basis for biodiversity conservation in agricultural landscapes. [ABSTRACT FROM AUTHOR]

Biological culture is of great significance to the conservation of biodiversity. The formation and development of botanical gardens have reflected the plant culture which formed by human beings due to material and spiritual needs in history. Modern botanical gardens have made outstanding achievements in plant ex-situ protection, while the plant culture construction is still a little insufficient. In the process of global biodiversity conservation, the important roles of traditional culture in biodiversity conservation and sustainable use of biological resources have been increasingly valued. At this background, this study emphasized the close connection and co-evolution relationship between biocultural diversity and biodiversity, and reviewed the implication of plant culture in early botanical gardens and Chinese classical gardens. And through the analysis of the main functions of 3 085 modern botanical gardens around the world, we found that only 7.36% of botanical gardens carried out ethnobotanical research, while 11.18% carried out conservation biology research, and 17.18% worked out a plant conservation programme, which revealed the improvement of the protection function and the weakening of the cultural function of modern botanical gardens. Based on the demand for the construction of plant culture in the effective protection of plant diversity in the current botanical garden, this study further analyzed the deficiencies of plant culture construction in botanical gardens in China, including: (1) insufficient plant culture information data in plant species diversity information; (2) lack of consideration of benefit-sharing of traditional knowledge in biodiversity conservation; (3) lack of theme parks that display plant diversity with culture. Focused on the goal of plant diversity conservation and management in the China national botanical garden, we put forward the following suggestions on plant culture construction in the China national botanical garden system from three aspects, in order to provide a reference for the construction of a national botanical garden system with the characteristics of Chinese ecological civilization. Plant diversity protection and utilization: to strengthen the consideration of plant culture in the construction of plant diversity information and germplasm resource bank, encourage ethnobotanical research. Benefit-sharing: to establish access and benefit-sharing (ABS) standard procedures covering traditional knowledge to ensure fair and equitable benefit-sharing. Public participation: to consider display the regionality and uniqueness in China national botanical garden, and add ethnic plant culture theme parks or exhibition halls. [ABSTRACT FROM AUTHOR]

Understanding the origins of species richness patterns is a fundamental goal in ecology and evolutionary biology. Much research has focused on explaining two kinds of species richness patterns: (i) spatial species richness patterns (e.g. the latitudinal diversity gradient), and (ii) clade‐based species richness patterns (e.g. the predominance of angiosperm species among plants). Here, I highlight a third kind of richness pattern: trait‐based species richness (e.g. the number of species with each state of a character, such as diet or body size). Trait‐based richness patterns are relevant to many topics in ecology and evolution, from ecosystem function to adaptive radiation to the paradox of sex. Although many studies have described particular trait‐based richness patterns, the origins of these patterns remain far less understood, and trait‐based richness has not been emphasised as a general category of richness patterns. Here, I describe a conceptual framework for how trait‐based richness patterns arise compared to other richness patterns. A systematic review suggests that trait‐based richness patterns are most often explained by when each state originates within a group (i.e. older states generally have higher richness), and not by differences in transition rates among states or faster diversification of species with certain states. This latter result contrasts with the widespread emphasis on diversification rates in species‐richness research. I show that many recent studies of spatial richness patterns are actually studies of trait‐based richness patterns, potentially confounding the causes of these patterns. Finally, I describe a plethora of unanswered questions related to trait‐based richness patterns. [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]

Mudeungsan National Park is a tall mountain located in the middle of Gwangju City. It is a UNESCO Global Geopark recognised as a rich repository of biological resources with high plant species diversity. However, hiking trails created around the exposed bedrock on the slopes around the mountain's summit cause soil loss and habitat destruction. To conserve the plant ecosystem of Mudeungsan National Park sustainably, the present study was conducted to find a species that could indicate the conservation status of the ecosystem. We the sociological relationships between plants with the aim of restoring habitats and species diversity around the summit bedrock at Mudeungsan National Park. In particular, our goal was to provide basic data for projects aimed at improving future hiking trails in national parks by analysing the sociological relationships between Potentilla ancistrifolia var. dickinsii, which is a phytogeographically important plant, and its companion plants. Findings showed high centrality of Miscanthus Sinensis, Lespedeza bicolor, Rhododendron schlippenbachii, Carex lanceolate, Arundinella hirta, and Rubus crataegifolius in the plant social network on the summit ridge of Mudeungsan. The analysis of the plant social network around P. ancistrifolia var. dickinsii showed that the extent of destruction of the ridge ecosystem could be determined by the changes in P. ancistriflolia. var. dickinsii cover, indicating that this species could be used as an indicator species. [ABSTRACT FROM AUTHOR]

The biodiversity of wood-inhabiting fungi on woody leguminous plants (WLPs) growing in the Middle Urals (Russia) has been studied for the first time. From 2002 to 2022, in Sverdlovsk oblast as a model region, 136 species of wood-inhabiting fungi were identified on WLPs: 127 species of Basidiomycota and 9 species of Ascomycota. Fungi develop on 12 out of 20 species of WLPs. The largest number of fungal species was found on the alien Caragana arborescens (115 species/84.5% of the total number of species), while two species were collected on Caragana decorticans,C. ussuriensis, and Laburnum alpinum each and one species was collected on Genista florida. A total of 122 species of fungi were found on nine alien WLPs, which is 4.1 times more than on three native species. The largest number of substrate-specific fungal species can be found to develop on C. arborescens (85/62.5%), four species on Chamaecytisus ruthenicus (2.9%), three species on Maackia amurensis (2.2%), two on Genista tinctoria and Robinia pseudoacacia each (1.5%), and one species on Caragana ussuriensis (0.7%). Nectria cinnabarina develops on the maximum number of substrates, seven WLP species; Xylodon sambuci on six species; and Peniophora cinerea and Schizophyllum commune on four species. In contrast, 71.3% of fungal species were found on one WLP species, and 27.2% of species are characterized by a single finding. For the first time for Sverdlovsk oblast, 14 fungal species are indicated, of which 86% were found in the parks of Ekaterinburg city and tree-lines along the roads, but only 14% were in natural conditions. In order to reveal the latitudinal–zonal specificity for the distribution of species richness of the WLP associated mycobiota, we use Aphyllophoroids as the largest group of fungi among all analyzed (75% of species), and Caragana arborescens, or Siberian peashrub is the richest plant substrate. Changes in the fungal diversity were studied along a meridional transect stretching for 800 km along 60° E, from the middle boreal subzone of Sverdlovsk oblast to the steppes of Chelyabinsk oblast (Russia) and Kostanay oblast (Kazakhstan). In each of the five vegetation zones/subzones, as well as in Ekaterinburg city, six sites were studied, the area of which varies from 0.9 to 6.8 ha. The aboveground phytomass of C. arborescens is maximal in the forest steppe (8.9–11.7 t/ha), and minimal at the edges of the transect (2.4–5.8 t/ha). A positive correlation was found between the aboveground plant phytomass and the species richness of mycobiota, while there was no correlation with climatic parameters. Notable differences were found in Ekaterinburg city: the Siberian peashrub phytomass was two times lower than in the forest steppe, but the species richness of mycobiota was similar to the forest steppe. A similar result was obtained for the α diversity (average number of fungal species at the sites and Shannon index) of mycobiota: an increase in the parameters from the middle boreal subzone to the forest steppe and a decrease in the steppe. The Whittaker and Czekanowski–Sørensen indices (β diversity) increase towards the steppe, which is due to a strong relationship with the mean annual temperature and precipitation. A range of fungal species gravitating towards northern, southern, and urbanized conditions has been revealed. In the north of transect, local species of fungi predominate, while in the south and in Ekaterinburg city, the role of biogeographically distant (alien) taxa is high. In this regard, the species composition of mycobiota of Siberian peashrub is divided into two clusters, northern (boreal) and southern (nemoral-steppe) ones, including Ekaterinburg city. To the south, the species richness of pathogenic fungi increases, but this parameter does not correlate with the C. arborescens phytomass. In plantings of invasive Siberian peashrub, the species richness of the poroid fungi is similar to that of the corticioid fungi at the local and regional level, which differs significantly from natural conditions. A high level of pathogenic fungi was also revealed compared to natural conditions. The results can be used to optimize the conception of Greenway planning in Ekaterinburg city and help prevent a number of environmental problems arising after the rapid implementation of the strategy for developing the city and the surrounding areas. [ABSTRACT FROM AUTHOR]

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Dramatic urbanization in the subtropical city of Hong Kong leads to enormous numbers of soil slopes. In addition to supporting infrastructure, soil slopes also allow revegetation work to enhance the ecological value of urban landscapes. However, groundcovers that exhibit much wider uses in slope revegetation, are often ignored. Our study mainly focused on the seasonal variation in groundcover on soil slopes and the association with slope performance and the degree of urbanization. The groundcovers in terms of plant cover, diversity and community composition on thirty-five soil slopes widespread in Hong Kong were examined. The groundcover abundance was then compared between wet and dry seasons and among districts with different degrees of urbanization. It was also correlated with various slope performances for any associations. The results showed considerably low plant cover (less than 50%) on soil slopes despite better performance in the wet season. The initially planted groundcovers have largely been replaced by a variety of naturally occurring plants, leading to a proliferation in species richness and plant diversity of revegetated slopes. Native ferns, including Blechnum orientale, Cyclosorus parasiticus and Dicranopteris pedata, dominated the landscape in both seasons. In addition, the plant diversity and community composition did not vary between seasons but indicated significant differences among urban and suburban districts. Regarding slope performance, slope angle imposed challenges to groundcover growth, as it showed a positive association with the plant community in the wet season but had a negative impact in the dry season. Slope openness and silt soil were found to have positive relationships with the groundcover community. Overall, although a more diverse groundcover community was observed, the poor formation of groundcovers on revegetated soil slopes indicated the need for improvement work to provide more sustainable urban landscapes. Highlights: • The seasonal variation in plant coverage, diversity and community composition of groundcovers on revegetated soil slopes in Hong Kong were assessed. • A generally low plant cover was found on soil slopes, with higher growth performance in the wet season. • Plant diversity and community composition of groundcovers did not vary between seasons but differed significantly among areas with different degrees of development. • Slope angle, canopy openness and soil texture were significantly associated with plant community composition. [ABSTRACT FROM AUTHOR]

Pine wilt disease (PWD), which is caused by the Bursaphelenchus xylophilus, is one of the most serious biological invasions in East Asia. Removal of infected pine trees is generally used to prevent the spread of PWD. However, how this strategy affects plant species diversity and ecosystem functions needs to be clarified. We compared alpha diversity, species composition, and biomass for all woody plant species, adults, saplings, and seedlings in infected Masson pine forests where removal of infected trees occurred (CTD) and where infected trees were retained (UTD), uninfected Masson pine forests (PMF), and evergreen broad-leaved forests (EBF). UTD had the highest alpha diversity of all species and saplings, and UTD and PMF had the lowest alpha diversity of seedlings. CTD and EBF had a similar composition of seedlings, and CTD and UTD had similar species composition of all plant species and saplings. UTD had the lowest biomass for all species and adults but had the highest saplings biomass. Soil properties were significantly related to plant biomass. The retention of infected trees likely maintained soil fertility which increased species alpha diversity and the biomass of saplings, and unchanged species composition compared to the removal of infected trees, indicating that the retention strategy could help to maintain ecosystem functions. [ABSTRACT FROM AUTHOR]

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

Causal effects of biodiversity on ecosystem functions can be estimated using experimental or observational designs — designs that pose a tradeoff between drawing credible causal inferences from correlations and drawing generalizable inferences. Here, we develop a design that reduces this tradeoff and revisits the question of how plant species diversity affects productivity. Our design leverages longitudinal data from 43 grasslands in 11 countries and approaches borrowed from fields outside of ecology to draw causal inferences from observational data. Contrary to many prior studies, we estimate that increases in plot-level species richness caused productivity to decline: a 10% increase in richness decreased productivity by 2.4%, 95% CI [−4.1, −0.74]. This contradiction stems from two sources. First, prior observational studies incompletely control for confounding factors. Second, most experiments plant fewer rare and non-native species than exist in nature. Although increases in native, dominant species increased productivity, increases in rare and non-native species decreased productivity, making the average effect negative in our study. By reducing the tradeoff between experimental and observational designs, our study demonstrates how observational studies can complement prior ecological experiments and inform future ones. Isolating the relationships between biodiversity and ecosystem functioning in natural ecosystems is challenging. Here, the authors apply a causal inference approach to observational data from grasslands and find a negative effect of biodiversity on productivity driven by non-native and rare species. [ABSTRACT FROM AUTHOR]

Anthropogenic nutrient enrichment and shifts in herbivory can lead to dramatic changes in the composition and diversity of aboveground plant communities. In turn, this can alter seed banks in the soil, which are cryptic reservoirs of plant diversity. Here, we use data from seven Nutrient Network grassland sites on four continents, encompassing a range of climatic and environmental conditions, to test the joint effects of fertilization and aboveground mammalian herbivory on seed banks and on the similarity between aboveground plant communities and seed banks. We find that fertilization decreases plant species richness and diversity in seed banks, and homogenizes composition between aboveground and seed bank communities. Fertilization increases seed bank abundance especially in the presence of herbivores, while this effect is smaller in the absence of herbivores. Our findings highlight that nutrient enrichment can weaken a diversity maintaining mechanism in grasslands, and that herbivory needs to be considered when assessing nutrient enrichment effects on seed bank abundance. Seed banks are reservoirs of plant diversity. This study shows that nutrient addition decreases diversity of grassland seed banks, increases their similarity to aboveground communities and interacts with aboveground herbivory to affect their abundance. [ABSTRACT FROM AUTHOR]

Question: Foraging‐tunnel disturbances created by herbivorous mammals can influence the above‐ground plant biomass of grassland communities. The plateau zokor (Eospalax baileyi) was considered a focal animal for investigating the effect of foraging‐tunnel disturbances created by herbivorous mammals on the above‐ground biomass and species richness of graminoids and forbs. Here, we ask how foraging‐tunnel disturbances created by plateau zokors influences above‐ground plant biomass and species richness of graminoids and forbs in alpine grasslands. Location: The study was conducted at three sites of alpine grasslands in the Qinghai‐Tibetan Plateau, China. Methods: In this study, all vascular plants were divided into graminoids and forbs, and 30 paired quadrats were randomly selected from each site. In total, 90 tunnel quadrats and 90 non‐tunnel quadrats were surveyed and sampled. Results: This study showed that foraging‐tunnel disturbances decreased the plant species richness of the grassland community and forbs by 16.5% and 17.7% respectively, whereas the response of graminoid species richness to foraging‐tunnel disturbance was different among the three sites, in which foraging‐tunnel disturbance decreased the graminoid species richness at Maqu and Xiahe sites and had no impact on the graminoid species richness at Tianzhu site. Regarding forbs, some legumes identified in the non‐tunnel quadrats were not observed in the tunnel quadrats. The foraging‐tunnel disturbances resulted in an above‐ground plant biomass decrease of 21.9% in the grassland community, 27.3% in forbs, and 17.2% in graminoids respectively. The percentage of graminoids in the above‐ground plant biomass increased from 50.4% in non‐tunnel quadrats to 55.5% in tunnel quadrats, a relative increase of 10.1% from the initial percentage. Conclusions: These results indicate that the foraging‐tunnel disturbances seemed to improve the forage availability for livestock in tunnel quadrats due to a higher relative proportion of graminoids in the grassland plant community, despite a decrease in graminoid biomass. However, the tunnels not only decreased the above‐ground plant biomass and species richness of forbs, but also might have a negative impact on soil nitrogen input because of the absence of some legumes. The findings of this study suggest that reseeding some legumes is an effective approach to maintaining plant diversity and soil fertility, which can compensate for the negative effect of foraging‐tunnel disturbance on alpine grasslands. [ABSTRACT FROM AUTHOR]

Questions: Soil resource heterogeneity influences the outcome of plant–plant interactions and, consequently, species co‐existence and diversity patterns. The magnitude and direction of heterogeneity effects vary widely, and the processes underlying such variations are not fully understood. In this study, we explored how and under what resource conditions small‐scale heterogeneity modulates grassland plant diversity. Location: Oderhänge Mallnow, Potsdam, Brandenburg, Germany. Methods: We expanded the individual‐based plant community model (IBC‐grass) to incorporate dynamic below‐ground resource maps, simulating spatial heterogeneity of resource availability. Empirical centimeter‐scale data of soil C/N ratio were integrated into the model, accounting for both configurational and compositional heterogeneity. We then analyzed the interplay between small‐scale heterogeneity and resource availability on the interaction and co‐existence of plant species and overall diversity. Results: Our results showed significant differences between the low‐ and high‐resource scenarios, with both configurational and compositional heterogeneity having a positive effect on species richness and Simpson's diversity, but only under low‐resource conditions. As compositional heterogeneity in the fine‐scale C/N ratio increased, we observed a positive shift in Simpson's diversity and species richness, with the highest effects at the highest level of variability tested. We observed little to no effect in nutrient‐rich scenarios, and a shift to negative effects at the intermediate resource level. The study demonstrates that site‐specific resource levels underpin how fine‐scale heterogeneity influences plant diversity and species co‐existence, and partly explains the divergent effects recorded in different empirical studies. Conclusions: This study provides mechanistic insights into the complex relationship between resource heterogeneity and diversity patterns. It highlights the context‐dependent effects of small‐scale heterogeneity, which can be positive under low‐resource, neutral under high‐resource, and negative under intermediate‐resource conditions. These findings provide a foundation for future investigations into small‐scale heterogeneity–diversity relationships, contributing to a deeper understanding of the processes that promote species co‐existence in plant communities. [ABSTRACT FROM AUTHOR]

The Puuc Biocultural State Reserve (PBSR) is a unique model for tropical dry forest conservation in Mexico. Preserving forest biodiversity and carbon within the PBSR depends on maintaining low-impact productive activities coordinated by multiple communal and private landowners. In this study, we used state-of-the-art remote sensing data to investigate past spatial patterns in forest clearing dynamics and their relation to forest carbon density and forest plant species richness and diversity in the context of the forest conservation goals of the PBSR. We used a Landsat-based continuous change detection product for the 2000–2021 period and compared it to carbon density and tree species richness models generated from ALOS-2 PALSAR 2 imagery and national scale forest inventory data. The estimated error-adjusted area of detected annual forest clearings from the year 2000 until the year 2021 was 230,511 ha in total (±19,979 ha). The analysis of annual forest clearing frequency and area suggests that although forest clearing was significantly more intensive outside of the PBSR than within the PBSR during the entire 2000–2021 period, there is no evidence suggesting that the frequency and magnitude of forest clearing changed over the years after the creation of the PBSR in 2011. However, an emergent hotspot analysis shows that high spatiotemporal clustering of forest clearing events (hotspots) during the 2012–2021 period was less common than prior to 2011, and these more recent hotspots have been confined to areas outside the PBSR. After comparing forest clearing events to carbon density and tree species richness models, the results show that landowners outside the PBSR often clear forests with lower carbon density and species diversity than those inside the PBSR. This suggests that, compared to landowners outside the PBSR, landowners within the PBSR might be practicing longer fallow periods allowing forests to attain higher carbon density and tree species richness and hence better soil nutrient recovery after land abandonment. In conclusion, our results show that the PBSR effectively acted as a stabilizing forest management scheme during the 2012–2021 period, minimizing the impact of productive activities by lowering the frequency of forest clearing events and preserving late secondary forests within the PBSR. We recommend continuing efforts to provide alternative optimal field data collection strategies and modeling techniques to spatially predict key tropical forest attributes. Combining these models with continuous change detection datasets will allow for underlying ecological processes to be revealed and the generation of information better adapted to forest governance scales. [ABSTRACT FROM AUTHOR]

In order to study the relationship between plant species diversity of middle and low altitude mountainous areas in southern Shaanxi and slope aspect and elevation, 91 representative quadrats were set up and selected in the study area and the species diversity and relationship of arbor layer, shrub layer and herb layer in every 150 m altitude range were statistically analyzed. The results showed that: (1) there were 460 species of vascular plants belonging to 129 families, 312 genera in the study area; the number of species of arbors, shrubs and herbs in shady slope was more than that in sunny slope. In the same slope, the number of species of herbaceous plants was the highest, covering the most families and genera, followed by shrubs and trees. (2) Except for the H and D values of herbaceous plants, the coefficient of variation of other species diversity index in shady slope was greater than that in sunny slope; on sunny slope, above 1250 m altitude, the number of herbaceous plant species decreased gradually and the dominant species gradually appeared; on shady slope, at 500-650 m altitude, the number of herbaceous plant species was the largest, while the number of shrub individuals was the largest at 1400-1550 m altitude. (3) In the regression analysis, the diversity index and the altitude mostly showed a good fitting effect. The diversity index of arbor layer in shady slope and sunny slope first decreased and then increased. The H and M values of arbor layer in shady slope were higher than those in sunny slope above 950 m altitude, and the difference was significant (P < 0.05), but the difference of D and J was not obvious. The H, J and M values of shrub layer on shady slope showed a single peak pattern at 800 m; H and M values of shrub layer on sunny slope increased monotonously in the study area, but there was no good fitting effect between J value and altitude. In the study area, the values of H, J and M of herbaceous layer on sunny slope first increased and then decreased with the increase of altitude, while the indexes of herbaceous layer on shady slope had no good fitting effect with altitude. (4) In the correlation test among different layers, H value of arbor layer on sunny slope was significantly negatively correlated with H, D and M of shrub layer (0.01 < P ≤ 0.05), and the J value of arbor layer was significantly positively correlated with that of shrub layer, and J value of shrub layer was significantly positively correlated with that of herb layer (0.01 < P ≤ 0.05). The diversity index of shrub on shady slope had significant or extremely significant positive correlation with each index of herb layer (except D value), but other correlations were not significant. (5) The peak value of interspecific co-occurrence rate on sunny slope was between 800-950 m and 950-1100 m, and the lowest value of that was between 1100-1250 m and 1250-1400 m. The peak altitude of shady slope is 100-400 meters higher than that of sunny slope, and the lowest value is in the same altitude range as that of sunny slope. [ABSTRACT FROM AUTHOR]

In order to reveal the influence of highway construction on the natural grassland and ecological system in Qinghai-Tibet Plateau, two representative construction points at a distance of 17 km which are ongoing construction area of S10 Zhuoni-Hezuo expressway in Gannan Tibetan autonomous prefecture of Gansu province were investigated. The sampling sites were 10 and 500 m away from the construction red line, and the sampling dates were June and September 2021. Line transect method was used to collect the samples, and species composition, coverage, height and biomass of plant community were calculated; the composition of plant community and species diversity were analyzed by SPSS software, and the least significant difference(LSD)method was used to test the significance of the above indexes, meanwhile the influences of highway construction on plant species, growth and diversity were discussed. The results show that there are 86 plant species presenting in investigation sites and the important values of Kobresia capillifolia, K. tibetica and Elymus nutans are higher; there are no significant difference between two investigation sites or between two distances(10 and 500 m away from the red line of highway construction)in the same location for most of the indices; only Shannon index and biomass of plant have significant difference(P<0.05)in a few sampling sites, suggesting that there is little difference of plant community composition in the investigation sites and the different distances away from the red line of highway construction. The vegetation height, average height, biomass and Menhinick index of plant in September are significantly higher(P<0.05)than those in June, indicating that the plants away from the red line of highway construction recover naturally and grow normally through their own adaptation, although the highway construction partially destroys and affects the surrounding natural environment. In general, under strict control of construction behavior, plant communities and growth in different distances away from the red line of highway construction have little change, and the damages to the ecosystem are relatively small. [ABSTRACT FROM AUTHOR]

Temperate forests of the Eastern Himalayan region are undergoing a noticeable transformation due to invasion and over-dominance by indigenous Yushania maling, Maling bamboo. In the present study, the impact of invasion of Maling bamboo on forest species composition in the Senchal Wildlife Sanctuary located in Darjeeling district of West Bengal, India was investigated, using a comparative approach. Ten plots each from Maling and non-Maling habitats at 10 sites were sampled using the nested quadrat method. Malinginfested plots showed lower species richness and diversity compared to non-Maling plots. The Maling-infested plots harboured 119 species compared to 165 species in non-Maling plots. Across habitat and vegetation strata, diversity indices such as Shannon-Weiner, Menhinick, Simpson, and evenness consistently indicated lower diversity in Maling-dominated habitats accompanied by higher dominance scores. Significantly lower shrub and herb species diversity were observed in Maling plots, along with elevated shrub density and moderately lower tree density as compared to non-Maling plots. The sapling species diversity and density were significantly lower in Maling plots, along with moderately reduced seedling density. The average Maling culm density was 1232.8 per 0.04 ha. These results underscore the adverse impact of Maling bamboo over-dominance on species composition of shrub, herbs, sapling and seedlings, and the density of trees, shrubs, saplings and seedlings within the temperate forests. Potential management strategies for the native species are discussed. [ABSTRACT FROM AUTHOR]

Plant species diversity (PSD) regulates ecosystem structure and functions, and is a key issue we need to consider when design vegetation restoration projects. Increasing PSD has been shown to promote or decrease soil nitrogen (N) availability, but the underlying mechanisms have not been well explored.Here, 45 plots with the Shannon–Weiner indices ranging from 0.15 to 3.57 were selected in a subtropical forest to explore the effect of PSD on soil N transformations.Higher PSD significantly enhanced the rates of gross N mineralization, gross nitrification, microbial N immobilization, net N mineralization, net nitrification and the contents of soil total N and inorganic N. Structural equation modelling showed that PSD indirectly impacted gross N transformations via its roles in regulating soil organic matter, mineral and microbial traits. Higher PSD stimulated gross N mineralization and nitrification mainly via its positive effects on microbial biomass content and gene abundances of chiA, archaeal or bacterial amoA, while increased microbial N immobilization mainly due to its stimulation of soil organic matter.Synthesis and applications. Our findings highlight the crucial role of PSD in stimulating soil N availability and provide a mechanistic understanding which can be integrated into Earth system models to better predict soil N availability and C sequestration in response to PSD. [ABSTRACT FROM AUTHOR]

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