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It is well known that biodiversity and ecosystem multifunctionality (EMF) guarantee the well-being of human society. Most studies have focused on the relationship between biodiversity and ecosystem function, and less is known about the individual and combined effects of above- and below-ground biodiversity on ecosystem multifunctionality under grazing disturbance. The aim of our study was to investigate the relationship between plant and soil microbial (bacterial and fungal) diversity and ecosystem multifunctionality under grazing disturbance by using multiple methods to assess ecosystem multifunctionality. We conducted experiments in desert grasslands on the northern slopes of the Tian Shan Mountains and compared the relationship between ecosystem multifunctionality and biodiversity assessed by different methods under light grazing and heavy grazing. Our results showed that at the heavy grazing level, ecosystem multifunctionality calculated by the mean method and plant diversity, soil fungal diversity, soil bacterial diversity and soil fertility calculated by the single function method showed a significant decrease (p < 0.05), but grass productivity was significantly increased (p < 0.05). Among them, ecosystem multifunctionality, soil carbon storage function and soil fertility all showed significant positive correlations with plant diversity and soil microbial diversity (p < 0.05). We calculated that ecosystem multifunctionality also essentially showed positive correlation with plant diversity and soil microbial diversity using the multi-threshold method, and the effect curve was approximately a single-peaked curve, first increasing and then decreasing. Finally, we used plant diversity, soil fungal diversity and soil bacterial diversity under grazing disturbance as biotic factors and soil pH as an abiotic factor to construct structural equation models, and we found that grazing can have direct effects on ecosystem multifunctionality and indirect effects on ecosystem multifunctionality through above- and below-ground biodiversity. Our study emphasizes the importance of the combination of above- and below-ground biodiversity in maintaining the multifunctionality of desert grassland ecosystems on the northern slopes of the Tian Shan Mountains. A moderate reduction in grazing intensity can better conserve biodiversity and improve ecosystem multifunctionality, and it is a feasible strategy to maintain sustainable management of desert grasslands. [ABSTRACT FROM AUTHOR]

Abstract Amazonia encompasses extensive forests in areas that are periodically inundated by overflowing rivers. The inundation depth and duration vary according to the slope of the terrain and distance to major water bodies. This creates a flooding gradient from the lowest lying seasonally flooded forest up into the unflooded forest, which directly affects the biota. However, the effect of this gradient on soil organisms remains elusive. Here, we use DNA metabarcoding to estimate prokaryote and eukaryote diversity from soil and litter samples along the flooding gradient in central‐western Amazonia using 16S and 18S gene sequences, respectively. We characterize the below‐ground diversity and community composition based on amplicon sequence variants (ASVs). We examine relationships between the soil biota and the flooding gradient, soil properties, and above‐ground woody plant diversity. The flooding gradient does not explain below‐ground biodiversity, nor is below‐ground diversity explained by the above‐ground woody plant diversity. We uncover several taxonomic groups—such as Patescibacteria—not previously reported from Amazonian seasonally flooded forests. The flooding gradient and woody plant diversity partly explain the community composition of soil bacteria. Although the effects of the flooding gradient, soil properties, and above‐ground woody plant diversity are difficult to quantify, our results indicate that flood stress may influence below‐ground bacterial community composition.

In desert ecosystems, the desertification process is characterized by increasing attenuation of plant productivity and deterioration of soil habitats, leading to enhanced environmental stress gradients for soil microbiomes. Despite the significance of microbial communities for multifunctionality in terrestrial ecosystems, the feedback dynamics of microbiomes and their contributions to maintaining deep soil (20–100 cm) multifunctionality as desertification progresses have yet to be evaluated. Here, we used three sites with different desertification stages and investigated the variation trends of microbiomes in soil profiles (0–100 cm) and their contributions to regulating multifunctionality. The multifunctionality did not exhibit a significant difference between superficial (0–20 cm) and deep soils and slightly decreased as depth increased throughout the entire profile. Results from alpha‐ and beta‐diversity analysis of soil microbiomes suggested that bacterial communities received on average more positive and progressive feedback from desertification development than fungal and archaeal communities. Particular microbial clades rather than total microbial diversity best predict and explain the vertical profile variation in soil multifunctionality in desert ecosystems. Microbial clades within Acidobacteria could be targeted for future soil‐focussed, bottom‐up desertification control studies. [ABSTRACT FROM AUTHOR]

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The reasons for the lack of inclusion of below-ground biodiversity in the Kenyan policy and legal framework were sought. Gaps were identified in the relevant sectoral policies and laws in regard to the domestication of the Convention on Biological Diversity (CBD). Below -ground biodiversity had no specific schedule in any of the sectoral laws. Most sectoral laws were particular about the larger biodiversity and soils but had no mention of below-ground biodiversity. Material Transfer Agreements and Material Acquisition Agreements that are regarded as tools of domestication of the CBD to guide transfers, exchanges and acquisition of soil organisms lacked a regulating policy. The lack of regulating policy could be attributed to the delay in approval of draft regulations by the Ministry of Environment while the lack of inclusion of below-ground biodiversity in Kenya’s legal and policy framework could be as a result of lack of awareness and appreciation among stakeholders.

Anthropogenic pressures on tropical forests are rapidly intensifying, but our understanding of their implications for biological diversity is still very limited, especially with regard to soil biota, and in particular soil bacterial communities. Here we evaluated bacterial community composition and diversity across a gradient of land use intensity in the eastern Amazon from undisturbed primary forest, through primary forests varyingly disturbed by fire, regenerating secondary forest, pasture, and mechanized agriculture. Soil bacteria were assessed by paired-end Illumina sequencing of 16S rRNA gene fragments (V4 region). The resulting sequences were clustered into operational taxonomic units ( OTU) at a 97% similarity threshold. Land use intensification increased the observed bacterial diversity (both OTU richness and community heterogeneity across space) and this effect was strongly associated with changes in soil pH. Moreover, land use intensification and subsequent changes in soil fertility, especially pH, altered the bacterial community composition, with pastures and areas of mechanized agriculture displaying the most contrasting communities in relation to undisturbed primary forest. Together, these results indicate that tropical forest conversion impacts soil bacteria not through loss of diversity, as previously thought, but mainly by imposing marked shifts on bacterial community composition, with unknown yet potentially important implications for ecological functions and services performed by these communities. [ABSTRACT FROM AUTHOR]

Soil properties are the product of current land use as well as legacies of historic use. Disentangling these effects is particularly challenging in tropical landscapes where plot-level land use history consists of varied sequences of uses punctuated by periods of abandonment. Here, we studied the soils of 63 plots in three sites of the Los Tuxtlas Biosphere Reserve, Mexico, and used detailed landowner accounts of land use history to model the effects of land use and its legacies. Electrical conductivity, N-NO 3 − and ant species richness were higher in current land uses featuring developed canopies (forests, secondary growth and palm and coffee plantations) compared to intensive land uses (livestock pastures and maize-slash and burn). Land uses aimed at soil restoration (maize-mucuna and tree plantations on degraded soils) improved soil bulk density only with respect to intensive land uses. The most frequent effects of historical land use variables (time since forest felling and cumulative times under each land use type) on soil properties occurred in interaction with each other and independently of the current land use. Beta glucosidase activity, pH and nematode richness were explained exclusively by historical use. In general, the duration of use dictated soil deterioration; however, the accumulation of time under intensive land uses had stronger legacies, in terms of soil physical and chemical properties, compared to that under agroforestry (coffee and palm cultivation). The richness of four taxa was sensitive to the land use history variables. Surprisingly, Nematoda and plant symbionts (nitrogen fixing bacteria and arbuscular mycorrhizal fungi) richness, but not that of Coleoptera, increased with accumulated time (20–40 yr) under maize cultivation. We suggest that the long history of traditional maize cultivation in polycultures has permitted the development of a rich soil biota. The current physical, chemical and biological properties of soils result from the combined effects of current land use and the legacies of land use history. In this study we found that current land uses explain several soil characteristics in Los Tuxtlas, independently of land use history (top-middle panel). The legacies of past land use (positive and negative for soil conservation) are sometimes only apparent in particular land uses (interactions in bottom-middle panel), but most often occur independently of current land use (right panel). Land use history was statistically modeled as the combined effect of time since forest felling and the cumulative times that plots spent under different land use types. Col = Coleoptera family richness, For = Formicidae sp. richness, AMF = arbuscular mycorrhizal fungi sp. richness, NFB = nitrogen fixing bacteria sp. richness, Nem = Nematoda genera richness, EC = electrical conductivity and Bg = beta glucosidase activity. Unlabelled Image • Soil properties were studied in 63 plots of Los Tuxtlas, Mexico. • Accounts of land use history where used to model land use legacies. • Cumulative time under intensive land uses had the strongest legacies. • Land uses for soil restoration improved soil density relative to intensive uses. • Plots with more cumulative time used as maize polyculture improved biota richness. [ABSTRACT FROM AUTHOR]

Anthropogenic pressures on tropical forests are rapidly intensifying, but our understanding of their implications for biological diversity is still very limited, especially with regard to soil biota, and in particular soil bacterial communities. Here we evaluated bacterial community composition and diversity across a gradient of land use intensity in the eastern Amazon from undisturbed primary forest, through primary forests varyingly disturbed by fire, regenerating secondary forest, pasture, and mechanized agriculture. Soil bacteria were assessed by paired-end Illumina sequencing of 16S rRNA gene fragments (V4 region). The resulting sequences were clustered into operational taxonomic units (OTU) at a 97% similarity threshold. Land use intensification increased the observed bacterial diversity (both OTU richness and community heterogeneity across space) and this effect was strongly associated with changes in soil pH. Moreover, land use intensification and subsequent changes in soil fertility, especially pH, altered the bacterial community composition, with pastures and areas of mechanized agriculture displaying the most contrasting communities in relation to undisturbed primary forest. Together, these results indicate that tropical forest conversion impacts soil bacteria not through loss of diversity, as previously thought, but mainly by imposing marked shifts on bacterial community composition, with unknown yet potentially important implications for ecological functions and services performed by these communities., (© 2016 by the Ecological Society of America.)