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In high-altitude deserts, the vegetation is spatially structured as a mosaic of patches with vegetation and interpatches of bare soil. Shrub patches create microhabitats that facilitate the persistence of other organisms by ameliorating climate extremes and increasing soil nutrients and moisture. Although this facilitative effect has been studied mainly on shrub understorey plants, the positive influence of desert shrubs may extend to the local arthropod community. In this study, we examined the hypothesis that plant facilitation by the desert shrub species Ephedra multiflora and E. breana positively influences the epigeal arthropod communities of the Andean Puna. We found that arthropod abundance, richness and diversity were all higher on Ephedra shrub microsites relative to paired open microsites. The harsh environmental conditions prevailing in the Puna ecosystems and the protection and resources provided by plants could jointly explain the positive influence of Ephedra shrubs over the arthropod community. The growth of tourism and the boom for lithium, as well as the increasing drought expected for the region under climate change scenarios, strengthens the importance of conserving shrub cover in these ecosystems to sustain biodiversity and ecosystem functioning. Our results are also relevant for restoration projects that consider the whole biological community, where using Ephedra as foundation shrubs to support desert endemics could be a strategy for land restoration. [ABSTRACT FROM AUTHOR]

Introduction: The fugal importance in terrestrial ecosystems is significant. However, our knowledge based on fungal distribution and its diversity in natural communities, especially in semi-arid ecosystems, seems to low. To have proper information on fungal community structure and the impact of environmental factors on the community composition, we assessed fungal diversity accompanied by soil chemical properties. Materials and Methods: Soil sampling was done in two seasons, spring and autumn, from two different sites, which were both cold and warm in a semiarid ecosystem located in Kerman province, Iran. Soil chemical properties were measured according to standard methods. The fungal community was estimated by the next-generation sequencing of the ITS region (ITS1f-ITS2). Results: By Illumina Miseq data analysis, 1542 Operational Taxonomic Units in soil samples were identified. Variation in the fungal community between the two sampling sites may be because of remarkable differences in environmental conditions, such as moisture and soil organic carbon. The dominant phylum was Ascomycota, followed by Basidiomycota. Discussion and Conclusion: Various fungi were identified in this ecosystem. Further studies are necessary to reveal the possible roles of the dominant fungal species inhabiting semiarid soils. [ABSTRACT FROM AUTHOR]

Soil biota, such as root‐associating fungal mutualists and pathogens, influence plant–plant interactions. Yet, the context‐dependency of their effects remains poorly understood, hindering our ability to predict plant invasions. We targeted Centaurea stoebe, an invasive plant which is more successful in arid than mesic North American grasslands. We asked how the abundances of the arbuscular mycorrhizal (AM) fungi and potentially pathogenic fungi are moderated by soil moisture and if shifts in these guilds correspond with C. stoebe growth and competitiveness.We grew C. stoebe plants in pots with every combination of three treatments: soil moisture (wet, dry), soil biota (sterile, live) and competition (none, native grass Bromus marginatus). We measured plant responses and root colonization by AM fungi, identified the relative sequence abundance of AM and potentially pathogenic fungi via guild matches of ITS2 sequences in the database FUNGuild, and examined shifts in AM and potentially pathogenic fungal communities based on the SSU rRNA gene and ITS2, respectively.Soil biota reduced C. stoebe growth in wet but not dry soils, and the presence of the native competitor Bromus marginatus exacerbated these effects. This shift in responsiveness corresponded with relatively fewer AM and more potentially pathogenic fungi in C. stoebe roots grown in wet soils, and vice versa in dry soils. Furthermore, in dry soils, C. stoebe's AM fungal community was strongly dominated by Glomus spp. Conversely, B. marginatus response to soil biota was not affected by soil moisture, and shifts in relative abundance of potentially pathogenic and AM fungi were generally opposite to those observed in C. stoebe.These results suggest that soil biota effects on host plants are species‐specific and depend on soil moisture. Furthermore, native plants can promote pathogens in distantly related invasive neighbours, potentially generating biotic resistance. Thus, plant invasions may be mediated by interactions between soil biota, soil moisture, and identity of native competitor.Predicting invasions as the climate continues to change will require surveys and experiments across relevant landscape‐level gradients of invasion and environmental factors. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

Biodiversity is essential for the provision of multiple ecosystem functions simultaneously (ecosystem multifunctionality EMF). Yet, it remains unclear whether and how dominant plant species impact EMF. Here, we aimed at disentangling the direct from indirect above- and belowground pathways by which dominant plant species influence EMF. We evaluated the effects of two dominant plant species (Dasiphora fruticosa, and the toxic perennial plant Ligularia virgaurea) with expected positive and negative impacts on the abiotic environment (soil water content and pH), surrounding biological communities (plant and nematode richness, biomass, and abundance in the vicinity), and on the EMF of alpine meadows, respectively. We found that the two dominant plants enhanced EMF, with a positive effect of L. virgaurea on EMF greater than that of D. fruticosa. We also observed that dominant plants impacted on EMF through changes in soil water content and pH (indirect abiotic effects), but not through changes in biodiversity of surrounding plants and nematodes (indirect biotic pathway). Our study suggests that dominant plants may play an important role in promoting EMF, thus expanding the pervasive mass-ratio hypothesis originally framed for individual functions, and could mitigate the negative impacts of vegetation changes on EMF in the alpine meadows. [ABSTRACT FROM AUTHOR]

Background and aims: A major goal of community ecology focuses on trying to understand how environmental filter on plant functional traits drive plant community assembly. However, slopes positions- mediated soil environmental factors on community-weighted mean (CWM) plant traits in shrub community has not been extensively explored to analyze and distinguish assembly processes. Methods: Here, we surveyed woody shrub plant communities from three slope positions (foot, middle, and upper) in a low hilly area of Guilin, China to assess differences in functional trait CWMs and environmental factors across these positions. We also measured the CWMs of four plant functional traits including specific leaf area, leaf dry matter content, leaf chlorophyll content, and leaf thickness and nine abiotic environmental factors, including soil water content, soil organic content, soil pH, soil total nitrogen, soil total phosphorus, soil total potassium, soil available nitrogen, soil available phosphorus, and soil available potassium. We used ANOVA and Tukey HSD multiple comparisons to assess differences in functional trait CWMs and environmental factors across the three slope positions. We used redundancy analysis (RDA) to compare the relationships between CWMs trait and environmental factors along three slope positions, and also quantified slope position-mediated soil environmental filtering on these traits with a three-step trait-based null model approach. Results: The CWMs of three leaf functional traits and all soil environmental factors except soil pH showed significant differences across the three slope positions. Soil total nitrogen, available nitrogen, available potassium, and soil organic matter were positively correlated with the CWM specific leaf area and leaf chlorophyll content along the first RDA axis and soil total potassium, total phosphorous, and soil water content were positively correlated with the CWM leaf dry matter content along the second RDA axis. Environmental filtering was detected for the CWM specific leaf area, leaf dry matter content, and leaf chlorophyll content but not leaf thickness at all three slope positions. Conclusions: Ultimately, we found that soil environmental factors vary along slope positions and can cause variability in plant functional traits in shrub communities. Deciduous shrub species with high specific leaf area, low leaf dry matter content, and moderate leaf chlorophyll content dominated at the middle slope position, whereas evergreen species with low specific leaf area and high leaf dry matter content dominated in slope positions with infertile soils, steeper slopes, and more extreme soil water contents. Altogether, our null model approach allowed us to detect patterns of environmental filtering, which differed between traits and can be applied in the future to understand community assembly changes in Chinese hilly forest ecosystems. [ABSTRACT FROM AUTHOR]

Quantification of soil biological status, through investigation of edaphic communities' composition, constitutes an important factor for the assessment of the grassland ecosystems, including their protection. The structure of soil invertebrate communities was investigated for five grasslands under different chemical and organic treatments, for the first time in Romania. In order to accomplish this task, some structural parameters were quantified: numerical abundance, taxa richness, Shannon diversity index of taxa and equitability. We demonstrated the relationship between five environmental factors (vegetation coverage, soil temperature, soil acidity, soil resistance at penetration, soil moisture content) and the community structures of soil fauna. In total, 17 invertebrate groups were identified with a total numerical abundance of 14,953 individuals. Considering the numerical abundance, the dominant taxa were Acaridae, Collembola, Oribatida and Mesostigmata, the least dominant being Coleoptera, Opiliones and Araneae. In spatial dynamics the investigated plots were characterised specifically by soil invertebrates' communities' structures, highlighted by the varied values of structural parameters: by indicator taxa and by the characteristic average values of environmental parameters. Multivariate statistical analysis revealed that the most important environment parameters influencing the soil taxa were vegetation coverage (especially on Acaridae, Glycyphagidae and Formicoidea) and soil resistance at penetration (Nematoda and Coleoptera). This study constitutes a scientific argument for the usage of soil invertebrate communities as indicators of the ecological conservation status of some fertilised grasslands. [ABSTRACT FROM AUTHOR]

The underground community of soil organisms, known as soil biota, plays a critical role in terrestrial ecosystems. Different ecosystems exhibit varied responses of soil organisms to soil physical and chemical properties (SPCPs). However, our understanding of how soil biota react to different soil depths in naturally established population of salinity tolerant Tamarix ramosissima in desert ecosystems, remains limited. To address this, we employed High-Throughput Illumina HiSeq Sequencing to examine the population dynamics of soil bacteria, fungi, archaea, protists, and metazoa at six different soil depths (0–100 cm) in the naturally occurring T. ramosissima dominant zone within the Taklimakan desert of China. Our observations reveal that the alpha diversity of bacteria, fungi, metazoa, and protists displayed a linear decrease with the increase of soil depth, whereas archaea exhibited an inverse pattern. The beta diversity of soil biota, particularly metazoa, bacteria, and protists, demonstrated noteworthy associations with soil depths through Non-Metric Dimensional Scaling analysis. Among the most abundant classes of soil organisms, we observed Actinobacteria, Sordariomycetes, Halobacteria, Spirotrichea, and Nematoda for bacteria, fungi, archaea, protists, and metazoa, respectively. Additionally, we identified associations between the vertical distribution of dominant biotic communities and SPCPs. Bacterial changes were mainly influenced by total potassium, available phosphorus (AP), and soil water content (SWC), while fungi were impacted by nitrate (NO 3 -) and available potassium (AK). Archaea showed correlations with total carbon (TC) and AK thus suggesting their role in methanogenesis and methane oxidation, protists with AP and SWC, and metazoa with AP and pH. These correlations underscore potential connections to nutrient cycling and the production and consumption of greenhouse gases (GhGs). This insight establishes a solid foundation for devising strategies to mitigate nutrient cycling and GHG emissions in desert soils, thereby playing a pivotal role in the advancement of comprehensive approaches to sustainable desert ecosystem management. • Soil nutrients and diversity of soil biota across different soil depths in Tamarix ramosissima was investigated. • Declining pattern in the alpha diversity of soil biota was recorded with an increase in soil depth except archaea. • The most prevalent classes were Actinobacteria, Sordariomycetes, Halobacteria, Spirotrichea, and Nematoda. • AP and SWC influenced bacteria and protists, while AK affected fungi and archaea and metazoa by AP and pH. • Our findings provide a new perspective on the vertical distribution of soil biota in T. ramosissima in desert ecosystem. [ABSTRACT FROM AUTHOR]

Soil biodiversity constitutes the biological pillars of ecosystem services provided by soils worldwide. Soil life is threatened by intense agricultural management and shifts in climatic conditions as two important global change drivers which are not often jointly studied under field conditions. We addressed the effects of experimental short-term drought over the wheat growing season on soil organisms and ecosystem functions under organic and conventional farming in a Swiss long term trial. Our results suggest that activity and community metrics are suitable indicators for drought stress while microbial communities primarily responded to agricultural practices. Importantly, we found a significant loss of multiple pairwise positive and negative relationships between soil biota and process-related variables in response to conventional farming, but not in response to experimental drought. These results suggest a considerable weakening of the contribution of soil biota to ecosystem functions under long-term conventional agriculture. Independent of the farming system, experimental and seasonal (ambient) drought conditions directly affected soil biota and activity. A higher soil water content during early and intermediate stages of the growing season and a high number of significant relationships between soil biota to ecosystem functions suggest that organic farming provides a buffer against drought effects. [ABSTRACT FROM AUTHOR]

Soil salinity is a serious environmental issue in arid China. Halophytes show extreme salt tolerance and are grow in saline-alkaline environments. There rhizosphere have complex bacterial communities, which mediate a variety of interactions between plants and soil. High-throughput sequencing was used to investigated rhizosphere bacterial community changes under the typical halophyte species in arid China. Three typical halophytes were Leymus chinensis (LC), Puccinellia tenuiflora (PT), Suaeda glauca (SG). The dominant phyla were Proteobacteria, Actinobacteria, Chloroflexi, Gemmatimonadetes, Acidobacteria and Bacteroidetes, Suaeda glauca rhizosphere has stronger enrichment of Nitrospirae and Cyanobacteria. The Ace, Chao and Shannon indices were significantly higher in soils under LC and SG (P<0.05). Functional predictions, based on 16S rRNA gene by PICRUSt, indicated that Energy metabolism, Amino acid metabolism, Carbohydrate metabolism and Fatty acid metabolism are dominant bacterial functions in three halophytes rhizosphere soil. Carbon metabolism, Oxidative phosphorylation, Methane metabolism, Sulfur metabolism and Nitrogen metabolism in SG were significantly higher than that in LC and PT. Regression analysis revealed that rhizosphere soil bacterial community structure is influenced by soil organic matter (SOM) and soil water content (SWC), while soil bacterial community diversity is affected by soil pH. This study contributes to our understanding of the distribution characteristics and metabolic functions under different halophyte rhizosphere bacterial communities, and will provide references for the use of rhizosphere bacteria to regulate the growth of halophytes and ecological restoration of saline soil. [ABSTRACT FROM AUTHOR]

Digging and burrowing mammals modify soil resources, creating shelter for other animals and influencing vegetation and soil biota. The use of conservation translocations to reinstate the ecosystem functions of digging and burrowing mammals is becoming more common. However, in an increasingly altered world, the roles of translocated populations, and their importance for other species, may be different. Boodies (Bettongia lesueur), a commonly translocated species in Australia, construct extensive warrens, but how their warrens affect soil properties and vegetation communities is unknown. We investigated soil properties, vegetation communities, and novel ecosystem elements (specifically non‐native flora and fauna) on boodie warrens at three translocation sites widely distributed across the species' former range. We found that soil moisture and most soil nutrients were higher, and soil compaction was lower, on warrens in all sites and habitat types. In contrast, there were few substantial changes to vegetation species richness, cover, composition, or productivity. In one habitat type, the cover of shrubs less than 1 m tall was greater on warrens than control plots. At the two sites where non‐native plants were present, their cover was greater, and they were more commonly found on boodie warrens compared to control plots. Fourteen species of native mammals and reptiles were recorded using the warrens, but, where they occurred, the scat of the non‐native rabbit (Oryctolagus cuniculus) was also more abundant on the warrens. Together, our results suggest that translocated boodie populations may be benefiting both native and non‐native flora and fauna. Translocated boodies, through the construction of their warrens, substantially alter the sites where they are released, but this does not always reflect their historic ecosystem roles. [ABSTRACT FROM AUTHOR]

• Investigated community composition of soil bacteria, fungi, archaea, protists & metazoa across diverse soil profiles. • Observed declining alpha diversity of bacteria, archaea, and protists with soil depth, contrasting with fungi and metazoa. • Identified prominent classes like Actinobacteria, Sordariomycetes, Nitrososphaeria, Spirotrichea, and Nematoda. • Bacterial changes linked to TK, fungal dynamics to TN. Archaea influenced by AK, protists by NO 3 and metazoa by SWC. • Article offers new insights into soil biota's vertical distribution and response in K. caspia within desert ecosystem. Soil organisms play a pivotal role in terrestrial ecosystems, sparking growing curiosity about the comprehensive diversity of subterranean biota across large ecological levels. Soil inhabitants' exhibit varied responses to soil physicochemical properties (SPPs) across desert ecosystem. Yet, the knowledge of their population dynamics across different soil depths (SDs) in the indigenous natural dominant zone of Karelinia caspia , a primary desert shrub in China, remains limited. This study employed advanced illumina sequencing to assess soil bacteria, fungi, archaea, protist, and metazoa populations across six distinct SDs (0 to 100 cm) within the K. caspia desert landscape. Our findings indicate a descending alpha diversity pattern in bacteria, archaea, and protists as soil depth increases, contrary to fungi and metazoa, which exhibit the opposite trend. SDs significantly shape soil biota beta diversity, notably impacting bacteria, protists, and fungi, as revealed by Non-Metric Dimensional Scaling. Prominent classes include Actinobacteria, Sordariomycetes, Nitrososphaeria, Spirotrichea, and Nematoda for soil bacteria, fungi, archaea, protists, and metazoa, respectively. Correlation analysis between predominant biotic communities' vertical distribution and SPPs variations revealed total potassium (TK) and pH's pronounced influence on bacteria, while fungi were affected by total nitrogen (TN) and soil water content (SWC). Archaea exhibit sensitivity to SWC, available potassium (AK), and available phosphorus (AP); protists respond to C/N-Ratio, nitrate (NO 3), and total phosphorus (TP); metazoa correlate with SWC, pH, and NO 3. Overall, these findings offer valuable insights regarding population fluctuations of soil biota within naturally established K. caspia across vertical soil strata within China's desert ecosystem. [ABSTRACT FROM AUTHOR]

Revegetation is the most common procedure in the restoration of disturbed areas; this practice usually aims at reconstructing plant communities that can last without further management. A low‐cost strategy to assist these efforts is the application of ecological knowledge in the design of the restoration. Promoting ecological processes that enhance the functioning of the restored community could result in higher restoration success. Among these processes, plant–plant interactions, e.g., facilitation and competition, can play an important role, both facilitating and impeding the development of a self‐sustaining plant community. Although these processes have been well‐studied in nature, we rarely have sufficient knowledge about the whole plant community. To develop that knowledge, we leverage on a restoration experiment that took place after a mine toxic spill, where ~15,000 woody plants from 13 species were planted and geolocated. Species were planted in three mixtures mimicking natural communities found along soil moisture gradients (xerophyte, intermediate, and hydrophyte). Plantings also varied in density. Approximately 2,600 plants were monitored for damage status, survival, and growth, for 4 yr. We analyzed growth performance of six targeted species as a function of their damage status, planted mixture, and density. Growth was also assessed on the basis of neighboring plants, accounting for the species identity and distance to the focal plant. Results show that survival among planted species was relatively high and was mostly unaffected by mixture or density of the plantings. Only very damaged plants in one species experienced a decrease in survival with increasing density. Neighborhood effects on growth show positive, neutral, and negative interactions among the tested species; these also varied depending on the type of growth performance considered (height, crown area, diameter). The species‐specific results ranged from positive to negative, varying between pair of species and growth performance metric. Results gathered from our neighborhood analyses on plant growth provide valuable information for the design of planting schemes that could enhance the performance of the target species. The methods developed can be applied to other systems and species. Given the potential impacts that facilitation and competition may have during revegetation, these interactions could be considered in restoration operations. [ABSTRACT FROM AUTHOR]

Background and Aims Heterospecific pollen transfer may reduce the fitness of recipient species, a phenomenon known as reproductive interference. A theoretical study has predicted that distributions of species pairs affected by reproductive interference may be syntopic under negligible reproductive interference, sympatric but with partitioning at small spatial scale (i.e. allotopic) under weak interference, or exclusive when reproductive interference is strong. Verifying these predictions is essential for evaluation of the applicability of reproductive interference as a general assembly rule of biological communities. The aim of this study was to test these predictions in two sympatrically distributed wild Geranium species, G. thunbergii and G. wilfordii. Methods To measure the effect of reproductive interference, the associations between the relative abundance of the counterpart species and seed set in the focal species, and seed set reduction following mixed pollination, were analysed. The possibility of hybridization with viable offspring was examined by genotyping plants in the field and after mixed pollination. Fertility of putative hybrids was based on their seed set and the proportion of pollen grains with apertural protrusions. A transect study was conducted to examine spatial partitioning, and possible influences of environmental conditions (canopy openness and soil moisture content) on partitioning between the species were analysed. Key Results Neither abundance of the counterpart species nor heterospecific pollen deposition significantly affected seed set in the focal species, and hybridization between species was almost symmetrical. Putative hybrids had low fertility. The two species were exclusively distributed at small scale, although environmental conditions were not significantly different between them. Conclusions The allotopy of the two species may be maintained by relatively weak reproductive interference through bidirectional hybridization. Re-evaluation of hybridization may allow ongoing or past reproductive interference to be recognized and provide insight into the distributional relationships between the interacting plants. [ABSTRACT FROM AUTHOR]

Two contradictory niche-based processes, environmental filtering and competitive exclusion, are important ecological processes in community assembly. Quercus wutaishanica forests are the climax communities in the Qinling Mountains and the Loess Plateau, China. Since these areas are characterized by different climate and evolutionary histories, these forests could be a suitable study system to test the phylogenetic niche conservatism hypothesis. We compared variation in community assembly of two distinct Q. wutaishanica forest communities and analyzed how the variations are formed. Quercus wutaishanica forest communities had significantly different species pool, phylogenetic structure and phylogenetic diversity between the two regions that were driven by inconsistency in environment conditions and evolutionary history at the local scale. Soil ammonium nitrogen, soil water content, and nitrate nitrogen play a major role in phylogenetic beta diversity patterns. The effect of environmental filtering on community assembly was more significant on the Loess Plateau than in the Qinling Mountains. Our study also found that local environment is important in mediating the patterns of phylogenetic structure. These findings provide insights into the mechanisms of local community assembly. [ABSTRACT FROM AUTHOR]

[Display omitted] • Flow regulation can durably alter the natural trajectories of riparian communities. • Using vegetation resurvey, changes in plant preferences and strategies were tested. • In 40 years, abiotic conditions have become less hygrophilic and more sciaphilic. • In response, communities have become more competitive and less stress-tolerant. • Anthropogenic changes have favored more stable environments and more mature stages. Vegetation resurvey has proven effective in understanding long-term trajectories of plant communities. Combined with information related to ecological preferences and ecological strategies of plants, this framework can provide insight into the dynamics of communities and associated ecological processes over several decades. By comparing old and recent vegetation surveys, we sought to understand how past changes in flow and sediment regimes along a 100-km reach of the Rhône river still influence the structure of riparian plant communities. Specifically, we studied variations in the mean and dispersion values of light, nutrient availability and soil moisture, as well as of competitors, stress tolerators and ruderals, at the community scale over four decades and along connectivity and productivity gradients. Results showed that communities were composed of more hygrophilous and heliophilous species in old surveys and that this decrease in soil moisture and light over time was broadly consistent along environmental gradients. In response to these environmental changes, the ecological strategies of riparian vegetation have evolved into more competitive and less stress-tolerant communities. This was illustrated by the decline of the pioneer species Salix alba , but the increase in several post-pioneer woody species. Given that these changes were observed on almost all the plots studied, irrespective of their position along the connectivity and productivity gradients, our results reflect to some extent an overall evolution of the system towards more mature and closed successional stages. Thus, over a period of 40-years, and probably due to the legacy effects of anthropogenic modifications to flow and sediment regimes that have favored more stable riparian environments, a directional shift of riparian communities towards more advanced successional stages was highlighted. In a context where past and present anthropogenic stressors are accumulating, we infer that these changes in riparian ecosystem properties are probably irreversible and represent a major challenge for restoration. [ABSTRACT FROM AUTHOR]

• Habitat filtering is the dominant mechanism for building plant communities in the Gurbantunggut Desert. • Plant communities of different life types in the same habitat have different construction mechanisms. • The mechanism of community construction on different slopes is mainly influenced by short-lived plants. • Soil factors indirectly influence community phylogenetic diversity by affecting species richness. Analysis of the phylogenetic structure of a community based on the phylogenetic relationships among species in the community can reflect the ecological process of community composition and determine the mechanism of plant community construction. In this study, we analyzed the characteristics of the phylogenetic structure and diversity of plant communities in the Gurbantunggut Desert and their interactions with soil factors and explored the mechanisms of species maintenance in the communities. The results showed that the ecological traits of plants were conserved, habitat filtering was the primary process affecting plant communities, and the diversity of phylogeny was ranked as fixed dunes > semifixed dunes > mobile dunes. At different slope positions within the dune, there is greater phylogenetic diversity at the bottom and lower slope, and habitat filtering dominates community construction, with the dominant role of habitat filtering in the community diminishing as the slope position rises. The phylogenetic diversity of plant communities of different life types is ranked as short-lived plants > small trees and shrubs > annual and perennial herbs. On the bottom and lower slopes, short-lived plants and annual and perennial herbaceous communities are mainly influenced by habitat filtering. Habitat filterability decreased with increasing slope position. On the upper slopes and at the top, competitive exclusion effects between small trees and shrubs dominated. Our analysis shows that soil water content and organic carbon affect phylogenetic diversity mainly by influencing community species richness and that the interaction between soil water content, grain size and plant diversity leads to clustering of species with similar soil preferences, which in turn affects the phylogenetic structure of the community. In addition, the change from habitat filtering to intraspecific competition in plant community construction from the bottom to the top of the slope is mainly influenced by short-lived plant communities, and this type of plant needs to be given priority consideration in the conservation and restoration of desert plant communities. [ABSTRACT FROM AUTHOR]

The study of feedbacks between plants and soils (plant–soil feedbacks; PSFs) is receiving increased attention. However, PSFs have been mostly studied in isolation of abiotic and biotic drivers that could affect their strength and direction. This is problematic because it has led to limited predictive power of PSFs in "the real world," leaving large knowledge gaps in our ability to predict how PSFs contribute to ecosystem processes and functions. Here, we present a synthetic framework to elucidate how abiotic and biotic drivers affect PSFs. We focus on two key abiotic drivers (temperature and soil moisture) and two key biotic drivers (above‐ground plant consumers and below‐ground top‐down control of pathogens and mutualists). We focus on these factors because they are known drivers of plants and soil organisms and the ecosystem processes they control, and hence would be expected to strongly influence PSFs. Our framework describes the proposed mechanisms behind these drivers and explores their effects on PSFs. We demonstrate the impacts of these drivers using the fast‐ to slow‐growing plant economics spectrum. We use this well‐established paradigm because plants on opposite ends of this spectrum differ in their relationships with soil biota and have developed contrasting strategies to cope with abiotic and biotic environmental conditions. Finally, we present suggestions for improved experimental designs and scientific inference that will capture and elucidate the influence of above‐ and belowground drivers on PSFs. By establishing the role of abiotic and biotic drivers of PSFs, we will be able to make more robust predictions of how PSFs impact on ecosystem function. plain language summary is available for this article. Plain Language Summary [ABSTRACT FROM AUTHOR]

Two of the main goals of forensic science are (1) to estimate the time since death, or post mortem interval (PMI) and (2) to find the site where a dead body was buried. Soil testate amoebae and diatoms may be useful indicators for these goals. However, the structure and patchiness of the habitat appears to be a main driver for the amoeba and diatom soil communities (e.g., individual density). In case the soil substrate is very dry and nutrient-poor (as in our study), the influence of a dead body on the soil microfaunal community may be superimposed by natural environmental heterogeneity, especially soil moisture content. Further studies are necessary to clarify if protist abundance data are helpful for forensic investigations. [ABSTRACT FROM AUTHOR]

Abstract: Mid‐ to high‐latitude peatlands are a major terrestrial carbon stock but become carbon sources during droughts, which are increasingly frequent as a result of climate warming. A critical question within this context is the sensitivity to drought of peatland microbial food webs. Microbiota drive key ecological and biogeochemical processes, but their response to drought is likely to impact these processes. Peatland food webs have, however, been little studied, especially the response of microbial predators. We studied the response of microbial predators (testate amoebae, ciliates, rotifers, and nematodes) living in Sphagnum moss carpet to droughts, and their influence on lower trophic levels and on related microbial enzyme activity. We assessed the impact of reduced water availability on microbial predators in two peatlands using experimental (Linje mire, Poland) and natural (Forbonnet mire, France) water level gradients, reflecting a sudden change in moisture regime (Linje), and a typically drier environment (Forbonnet). The sensitivity of different microbial groups to drought was size dependent; large sized microbiota such as testate amoebae declined most under dry conditions (−41% in Forbonnet and −80% in Linje). These shifts caused a decrease in the predator–prey mass ratio (PPMR). We related microbial enzymatic activity to PPMR; we found that a decrease in PPMR can have divergent effects on microbial enzymatic activity. In a community adapted to drier conditions, decreasing PPMR stimulated microbial enzyme activity, while in extreme drought experiment, it reduced microbial activity. These results suggest that microbial enzymatic activity resulting from food web structure is optimal only within a certain range of PPMR, and that different trophic mechanisms are involved in the response of peatlands to droughts. Our findings confirm the importance of large microbial consumers living at the surface of peatlands on the functioning of peatlands, and illustrate their value as early warning indicators of change. [ABSTRACT FROM AUTHOR]

Abstract: Global climate change is affecting and will continue to affect ecosystems worldwide. Specifically, temperature and precipitation are both expected to shift globally, and their separate and interactive effects will likely affect ecosystems differentially depending on current temperature, precipitation regimes, and other biotic and environmental factors. It is not currently understood how the effects of increasing temperature on plant communities may depend on either precipitation or where communities lie on soil moisture gradients. Such knowledge would play a crucial role in increasing our predictive ability for future effects of climate change in different systems. To this end, we conducted a multi‐factor global change experiment at two locations, differing in temperature, moisture, aspect, and plant community composition, on the same slope in the northern Mongolian steppe. The natural differences in temperature and moisture between locations served as a point of comparison for the experimental manipulations of temperature and precipitation. We conducted two separate experiments, one examining the effect of climate manipulation via open‐top chambers (OTCs) across the two different slope locations, the other a factorial OTC by watering experiment at one of the two locations. By combining these experiments, we were able to assess how OTCs impact plant productivity and diversity across a natural and manipulated range of soil moisture. We found that warming effects were context dependent, with the greatest negative impacts of warming on diversity in the warmer, drier upper slope location and in the unwatered plots. Our study is an important step in understanding how global change will affect ecosystems across multiple scales and locations. [ABSTRACT FROM AUTHOR]

Abstract: Understanding the importance of biotic community structure on ecosystem functioning, and whether communities inhabiting different microhabitats in highly heterogeneous areas provide different ecological functions is a challenge in ecological research in the face of biodiversity and habitat loss. Biological soil crusts (BSCs) have been largely treated as unique entities, and have been mostly examined in interspaces between perennial plants, limiting current understanding of their role as drivers of ecosystem functioning and their relative contribution in comparison to vascular plants. We assessed the role of BSCs on ecosystem functioning in vegetated patches and interspaces, and how individual soil functions and ecosystem multifunctionality are related to changes in BSC species‐ and community‐level attributes. We contemplated nine ecosystem functions associated with soil water dynamics, nutrient cycling and erosion potential. We found that vegetated patches improve infiltration rates, soil stability and net potential nitrogen (N) mineralization compared to interspaces, and thus dominate multifunctionality. However, well‐developed BSCs improve soil moisture and N pool in both microsites, and are multifunctional stabilizing soils and regulating soil moisture and infiltration in the interspaces. BSC surface microstructure, including changes in total cover, species richness, morphological functional groups and surface discontinuities, has significant effects on soil moisture. Differences in soil N and phosphorous are mostly related to the presence of BSC‐lichens. The effect of BSCs on multifunctionality varies in dependence of the particular set of functions that are sought to simultaneously maximize. Our results suggest that vascular plants and BSCs have idiosyncratic effects on different key ecosystem functions and multifunction, and BSCs substitute vascular plants in stabilizing soils and regulating water dynamics in the interspaces. BSCs greatly contribute to small‐scale heterogeneity in the functioning of vegetated patches and interspaces, hence consideration of BSCs in different microsites is essential for enhancing our understanding of their functional relevance at a regional scale. In addition, quantification of BSC microstructure is crucial, owing to the contrasting effects of BSC species‐ and community‐level attributes on different functions and multifunction. A plain language summary is available for this article. [ABSTRACT FROM AUTHOR]

Habitat heterogeneity is expected to change community composition and diversity, with large implications for ecosystem processes and function. Understanding the potential mechanisms of habitat heterogeneity affecting community ecological processes is a central issue in biodiversity conservation. In this study, we use a spatial metrics analysis to quantify the spatial pattern of plateau zokor mounds. We integrated soil physicochemical variables and community characteristic data to understand the disturbance effect of plateau zokor mounds on community diversity at a microhabitat scale (400 m2). Results showed that plant species richness increased significantly with increasing disturbance levels. Increases in forb species were largely the reason for the increased plant diversity in the alpine meadow disturbed by plateau zokor mounds. Disturbance caused by the plateau zokor significantly increased the soil macroinvertebrate richness and abundance, with herbivorous taxa playing a key role. Mantel tests and redundancy analysis showed that the composition of plant and soil macroinvertebrate communities are significantly related to soil moisture and soil temperature, and the SEM model revealing soil moisture and soil temperature positive effects on plant and macroinvertebrate richness after plateau zokor disturbance. Furthermore, soil variables (moisture, temperature, and organic carbon) directly affected plant richness, and indirectly affected soil macroinvertebrate communities. Our results suggest that the spatial pattern of plateau zokor mounds facilitate greater biodiversity through increased habitat complexity and heterogeneity. Therefore, it can be regarded as a "key species" in the alpine grassland and researchers should pay more attention to the ecological effects of alpine rodent disturbance on grassland ecosystems. • Spatial metrics analysis can quantify environmental heterogeneity at microhabitat • The spatial pattern of mounds had the biggest effect on herbivorous invertebrate • The soil invertebrate are affected by soil physical properties and plant richness [ABSTRACT FROM AUTHOR]

Climate, litter quality and decomposers drive litter decomposition. However, little is known about whether their relative contribution changes at different decomposition stages. To fill this gap, we evaluated the relative importance of leaf litter polyphenols, decomposer communities and soil moisture for litter C and N loss at different stages throughout the decomposition process. Although both microbial and nematode communities regulated litter C and N loss in the early decomposition stages, soil moisture and legacy effects of initial differences in litter quality played a major role in the late stages of the process. Our results provide strong evidence for substantial shifts in how biotic and abiotic factors control litter C and N dynamics during decomposition. Taking into account such temporal dynamics will increase the predictive power of decomposition models that are currently limited by a single-pool approach applying control variables uniformly to the entire decay process. [ABSTRACT FROM AUTHOR]

In the mountainous rangeland of inland arid regions of Eurasia, seasonal grazing has been important to local communities for production of food, fiber, and for income, for the past thousand years. Recent population increases and other changes have put traditional grazing systems under pressure. However, empirical data describing soil properties or the impact of traditional grazing practice on the thresholds at which increase in animal stocking rate (SR) may result in degradation are lacking. Here, we provide, for alpine “typical steppe” at Qilian Mountain on the Tibetan plateau in China, a description of variation in some soil properties with soil depth, and with variation in grazing intensity. The soils studied have a humus-rich epipedon typically exceeding our sampling depth of 40 cm. As commonly reported, increased grazing intensity has correlated with depletion in soil organic carbon (SOC). Regression of our SOC data on SR indicated no “safe” threshold for grazing intensity below which SOC depletion would not occur. Other soil changes linked to increased grazing intensity in our study included a lowering of the carbon:nitrogen ratio (indicating possibly increased risk of nitrogen loss from farming systems to the wider environment), an increase in soil bulk density, a decrease in soil moisture content, and transfer of phosphorus from less intensively grazed areas toward animal night pens. Our study site is experiencing a climate warming trend which may be contributing to loss of SOC. [ABSTRACT FROM PUBLISHER]

• Soil nematode richness is relatively low on inshore islands. • Large island maintains high soil nematode abundance and diversity. • Edaphic and climatic-geographical factors drive variations in soil nematode compositions. Factors that influence the composition and diversity of soil nematode communities on oceanic islands are poorly understood. In this study, we evaluated the soil nematode communities and associated biotic and abiotic factors on five oceanic islands in the north of the South China Sea. We detected 38 nematode genera and found that bacterivores and fungivores were the dominant trophic groups, representing 54.2–70.4% and 15.1–35.3%, respectively, of total soil nematode abundance. The abundances of total soil nematodes and of all trophic groups, maturity, structure indices and nematode diversity were positively correlated with island latitude and area, and were negatively correlated with soil total K and annual temperature. In addition, the abundances of total soil nematodes, bacterivores, herbivores and nematode dominance index were positively associated with soil available K. The abundances of total soil nematodes, fungivores, herbivores, predators and omnivores, maturity, structure, Shannon diversity indices were positively related to soil moisture. Variation partitioning analysis showed that the combination of soil properties and climatic-geographical factors explained more of the variation (26.8–61.5%). The results suggest that larger island can maintain greater nematode diversity than smaller islands due to the greater diversity of habitats on larger island. The key climatic-geographical and edaphic factors affecting soil nematode communities were latitude, annual temperature, soil moisture and total K, respectively [ABSTRACT FROM AUTHOR]

Soil water use efficiency (SWUE) was proposed as an effective proxy of ecosystem water use efficiency (WUE), which reflects the coupling of the carbon–water cycle and function of terrestrial ecosystems. The changes of ecosystem SWUE at the regional scale and their relationships with the environmental and biotic factors are yet to be adequately understood. Here, we aim to estimate SWUE over northeast China using time-series Moderate Resolution Imaging Spectroradiometer (MODIS) gross primary productivity data and European Space Agency climate change initiative (ESA CCI) soil moisture product during 2007–2015. The spatio-temporal variations in SWUE and their linkages to multiple factors, especially the phenological metrics, were investigated using trend and correlation analysis. The results showed that the spatial heterogeneity of ecosystem SWUE in northeast China was obvious. SWUE distribution varied among vegetation types, soil types, and elevation. Forests might produce higher photosynthetic productivity by utilizing unit soil moisture. The seasonal variations of SWUE were consistent with the vegetation growth cycle. Changes in normalized difference vegetation index (NDVI), land surface temperature, and precipitation exerted positive effects on SWUE variations. The earlier start (SOS) and later end (EOS) of the growing season would contribute to the increase in SWUE. Our results help complement the knowledge of SWUE variations and their driving forces. [ABSTRACT FROM AUTHOR]