Search Results (41)

This study examines the effects of climatic variability on bacterial and fungal populations, as well as enzymatic activities innutrient-rich, organic soils that support tea plants (Camellia sinensis L). Conducted from 2016 to 2019 across five district tea estates (TEs) in the Jorhat district of Assam, India, this research investigates the intricate relationships among these parameters. The findings indicate that bacterial and fungal communities exhibit optimal growth within a temperature range of 18 to 30 °C, establishing a critical threshold for their metabolic activity. A significant positive correlation was observed between the abundance of these microbial populations and the corresponding soil enzymatic activities, underscoring the essential role of these robust microbial communities in sustaining vital soil processes. Hierarchical cluster analysis identified two distinct groups of TEs that displayed consistent patterns of microbial behaviour across varying seasonal conditions. Furthermore, principal component analysis demonstrated that the first three principal components accounted for over 80% of the variability observed in the microbial and enzymatic data sets. This research contributes valuable insights into the dynamic interactions between seasonal fluctuations and soil health, highlighting the crucial contributions of bacterial and fungal populations, along with their enzymatic activities, to the complex ecosystem underlying tea cultivation. Full article

Cultivation of perennial mixtures has emerged as an efficient way to produce a large amount of forage, supporting a sustainable livestock industry. The stability and sustainability of forage production is largely controlled by soil health. However, variation in soil health in perennial mixtures still needs further investigation under diverse conditions. Clarifying the relationships between soil physicochemical properties and microbial community is of great importance in better understanding soil health in perennial cultivated grasslands. The effects of mixing combination of alfalfa with timothy or smooth bromegrass on soil health were evaluated through comparing soil nutrients, enzyme activities, microbial community, and forage yield in alfalfa–grass mixtures and corresponding monocultures after seven years of establishment. Mixtures significantly increased forage dry matter yield by 61.39% and 1188.29% in the alfalfa–timothy mixture compared with alfalfa and timothy monocultures, respectively, and by 54.36% and 736.38% in the alfalfa–smooth bromegrass mixture compared with alfalfa and smooth bromegrass monocultures, respectively. Mixtures enhanced soil organic carbon, total nitrogen, nitrate nitrogen and ammonium nitrogen contents, and urease activity, but reduced microbial alpha diversity. Beneficial taxa, such as Bacillus, Paenibacillus, and Mortierella, were enriched. Soil nitrate nitrogen was identified as a key driver influencing bacterial functional composition, while soil organic carbon, ammonium nitrogen, water, alkaline phosphatase, and sucrase exhibited significant effects on fungal functional composition. This study demonstrated that alfalfa–grass mixtures enhance system productivity by improving soil physicochemical properties and reconstructing soil microbial community. It provides a theoretical basis from the viewpoint of soil health for establishing and managing sustainable cultivated grasslands. Full article

Elemental migration and enrichment are important processes influencing tea plant growth and the assembly of rhizosphere bacterial communities within the rock–soil–plant continuum. This study explores how soil parent materials (granite, quartz schist, and sericite schist) are potentially associated with these processes and their observed associations with the elemental composition of tea leaves. Exploratory statistical analyses revealed distinct, lithology-specific biogeochemical patterns that serve as a foundation for hypothesis generation. In granite soils, chlorite correlated with the mobility of Cr, Pb, Cu, Ni, Mg, and Na, coinciding with shifts in the relative abundances of Verrucomicrobia, Armatimonadetes, and Chloroflexi. In quartz schist, kaolinite exhibited notable correlations with the dynamics of Pb, Cr, Ni, Zn, and As, which were statistically linked to Planctomycetes, Proteobacteria, and Acidobacteria. Complex mineral–microbe interactions were observed in sericite schist soils, where clay minerals (e.g., chlorite, illite) were closely associated with the migration of multiple elements (Pb, K, Ca, Cd, As, Al, Fe, Zn), paralleling structural variations in communities of Actinobacteria, Planctomycetes, Chloroflexi, and Proteobacteria. Potassium (K), calcium (Ca), and manganese (Mn) showed bioaccumulation tendencies in tea leaves across all lithologies, with an enrichment capacity order of Ca > K > Mn > Mg > Na > Al. Exploratory Classification and Regression Tree (CART) analysis suggested that the migration of K, Ca, Cu, Zn, and Hg corresponded most closely with their soil concentrations. Manganese (Mn) exhibited a mineral-associated trend, with kaolinite content as a potential correlate, while cadmium (Cd) migration was statistically linked to the relative abundance of Armatimonadetes. These findings highlight potential candidate relationships between mineralogy, microbes, and elemental mobility rather than confirming causal mechanisms, emphasizing the need for further validation in larger or experimental datasets. Full article

In permanently submerged coastal wetlands, interactions between biogeochemical processes and microbial communities strongly influence greenhouse gas (GHG) fluxes. To improve our understanding of how redox-driven processes shape GHG dynamics in these ecosystems, we investigated the relationships among iron (Fe) pools, microbial dynamics, and the potential GHG production in subaqueous soils from an interdunal wetland in San Vitale Park (Italy), permanently submerged and affected by seasonal oscillations of the saline water table. Two subaqueous soil columns (WAS-2 and WAS-4), collected from similar settings, were analyzed. Surface layers of WAS-4 showed higher salinity and carbonate content, whereas WAS-2 was characterized by overall higher Fe concentrations. Distinct vertical distributions of organic matter and sulfur (S) were shown along depth. Laboratory incubations revealed that nitrous oxide (N₂O) production was up to ten times higher in WAS-2 than in WAS-4, with peaks in the top 13–14 cm, consistent with more active nitrification-denitrification in surface layers. Methane (CH₄) and carbon dioxide (CO₂) fluxes decreased with depth, reflecting reduced availability of labile carbon. Methanomicrobiales dominated CH₄-producing layers, indicating hydrogenotrophic methanogenesis, while amoA-carrying Nitrosomonadales and Thaumarchaeota, occurred in shallow, organic-rich layers where ammonia supported nitrification and denitrification. Denitrifiers mainly belonged to α- and β-Proteobacteria, consistent with their direct contribution to N₂O peaks. Spearman’s correlations showed N₂O positively correlated to sulfur and labile carbon (C), supporting denitrification under moderately reducing conditions. CH₄ and CO₂ positively correlated with organic C (Corg), total nitrogen (TN), and reactive Fe forms, reflecting redox-mediated microbial respiration and methanogenesis. Trace elements (B, Cr, Cu, Ni) acted as micronutrients or inhibitors depending on concentration. Canonical correspondence analysis indicated depth-structured links among gas fluxes, soil chemistry (Corg, TN, S/C, CaCO₃, P), and microbial distributions: surface layers, rich in labile C and nutrients, supported active bacteria and archaea involved in decomposition, nitrification, and denitrification, whereas deeper layers hosted oligotrophic archaea adapted to inorganic substrates. Overall, Fe pools appeared to be associated with soil processes relevant to GHG dynamics, although the extent of their regulatory role remains uncertain due to potential alterations of redox-sensitive Fe fractions during sample handling. These results contribute to broader efforts to predict GHG emissions in submerged wetland soils by linking redox stratification, inorganic chemistry, and microbial functional groups. Full article

Haloxylon ammodendron plantations constitute a dominant vegetation component of the desert–oasis ecotone in the arid and semi-arid regions of northwest China, playing a critical role in maintaining oasis stability and ecological security. However, the effects of converting natural desert ecosystems into plantations on the soil food webs of arthropods remain poorly understood, particularly with respect to how these effects vary across plantation age. To address this knowledge gap, we conducted a field investigation in the desert–oasis ecotone of the middle reaches of the Hexi Corridor, Gansu Province. Using pitfall trapping, we sampled two key arthropod taxa (arachnids and soil mesofauna) from control areas (natural deserts) and H. ammodendron plantations representing different ages (young and old). The results indicated that both young and old plantations were associated with significantly higher abundance and richness of arachnids, soil mesofauna, mites, and springtails compared with natural deserts, with springtail richness exhibiting a further significant increase in old plantations. Arachnid responses to plantation conversion were strongly structured by body size. Medium arachnid abundance increased in both young and old plantations, whereas large arachnid abundance increased only in young plantations and declined in older ones. In contrast, small arachnid abundance exhibited significant increases exclusively in old plantations. In addition, relationships between arachnid, mite and springtail abundance varied with plantation age: the ratio of large arachnids to mites and springtails declined significantly in old plantations relative to young ones, while the corresponding ratio for small arachnids showed an opposite pattern. Variations in soil mesofauna community composition were primarily explained by shrub cover, herbaceous cover, coarse sand proportion, silt-clay content, and soil soluble salt, which together accounted for 48.9% of observed variation. For arachnids, soil mesofauna as a food resource significantly enhanced abundance and richness. Moreover, shrub cover and silt-clay content were also drivers of arachnid community variation, jointly explaining 6.7% of variance. Overall, the establishment of H. ammodendron plantations promoted the diversity of both arachnids and soil mesofauna, but their relationships shifted dynamically with plantation age, leading to a reorganization of detrital food web structure and functioning. Full article

Subtropical deciduous broad-leaved forests in eastern China form a key ecotone between temperate and subtropical biomes, yet their vegetation–environment relationships remain insufficiently understood. This study examined community structure, species diversity, and their associations with topographic and soil variables in a 25 ha forest dynamics plot in the Lushan Mountains. All woody plants with a diameter at breast height (DBH) ≥ 1 cm were surveyed, and detailed topographic attributes and soil physicochemical properties were measured. Community structure showed strong linkages with species diversity: tree-layer structural characteristics were generally negatively correlated with diversity, whereas in the shrub layer, density was negatively but height and DBH were positively correlated with diversity. Species diversity in the two layers was positively associated, while tree-layer structure was negatively related to shrub-layer diversity. Among topographic factors, altitude and the topographic solar radiation aspect index (TRASP) exerted the strongest influences on soil properties, with altitude negatively correlated with soil pH and available nutrients but positively correlated with C:N, C:P, and total carbon, and TRASP showing negative correlations with most nutrients except total phosphorus. Redundancy analysis revealed that topographic heterogeneity and soil conditions jointly shaped community structure and species diversity, with soil C:N ratio, altitude, pH, total phosphorus, and total carbon emerging as key drivers. These findings demonstrate that areas with high plant diversity do not always correspond to high soil nutrient content and underscore the importance of integrating both topographic and edaphic factors into biodiversity conservation and forest management in subtropical deciduous broad-leaved forests. Full article

Coastal lagoons are critical socio-ecological systems that face increasing anthropogenic pressures, threatening their sustainability. Understanding how different social actors value Nature’s Contributions to People (NCPs) is essential for developing effective and legitimate governance approaches. This study examines how sociodemographic characteristics and social roles influence plural valuations of NCPs in the Tres Palos lagoon, Mexico. We collected data from different social actor types across three coastal communities, assessing perception values, orientation values, and change projections for eight NCPs, with a focus on pattern identification and hypothesis generation rather than causal inference. Multiple Correspondence Analysis revealed that social actor type (decision-makers and residents) emerged as the primary factor differentiating NCP valuations. Decision-makers consistently rated regulating contributions (habitat creation, climate regulation, and soil formation) as highly important and projected future declines attributed to external pressures. In contrast, residents assigned lower importance to these contributions and anticipated stability through community restoration efforts. Sex also influenced value orientations, with women displaying more egoistic (self-interest) orientations toward habitat creation and the regulation of freshwater and coastal water quality, while men expressed altruistic (interest in others) orientations toward physical and psychological experiences, as well as habitat creation. These valuation mismatches reflect fundamentally different relationships with lagoon ecosystems: institutional regulatory perspectives versus experiential subsistence viewpoints. The divergent responsibility attributions and future projections create governance challenges that traditional top-down approaches cannot adequately address. Our findings underscore the need for reflexive governance frameworks that recognize value pluralism and foster inclusive spaces for dialogue among diverse knowledge systems. This research contributes to the growing literature on plural valuation while providing practical insights for coastal ecosystem management in the context of the Global South. Full article

Given the increasing demand for water and the need to reduce energy consumption, modern wastewater treatment systems should be characterised by high pollutant removal efficiency while consuming low resources. Hydrophytic wastewater treatment plants with vertical flow through a soil-plant bed (VFCW) are one solution that meets these requirements. The efficiency of these systems largely depends on the biological activity of the bed, of which free-living soil nematodes are an important component. The study presented in this paper aimed to assess the relationship between the quality of domestic wastewater flowing into VFCW beds and the abundance and trophic structure of soil nematode communities. The analysis was carried out on two real-world sites, where VFCW beds were the third stage of the plant bed system. Both treatment plants received only domestic wastewater. Statistical analysis showed no significant differences (p > 0.05) in the physicochemical composition of the wastewater flowing into the two treatment plants, indicating homogeneous system feed conditions. Nevertheless, canonical correspondence analysis (CCA) showed that the relationships between effluent parameters and the abundance of individual nematode trophic groups differed in each bed, suggesting the influence of local environmental and biocenotic conditions. In particular, bacterivorous nematodes—key to bed function—were shown to be sensitive to different sets of variables at the two sites despite similar effluent composition. These results confirm that the rhizosphere—a zone of intense interactions between plant roots, microorganisms, and soil microfauna—plays a critical role in shaping the biological activity of the bed. Nematodes, particularly bacterivorous nematodes, support the mineralisation of organic matter and nutrient cycling, resulting in increased efficiency of treatment processes. The stability of the total nematode abundance, irrespective of inflow conditions, demonstrates the bed biocenosis high ecological resilience to external disturbances. The study’s results highlight the importance of an ecosystem approach in designing and managing nature-based solutions (NBS) treatment plants, which can be a sustainable component of sustainable water and wastewater management. Full article

Soil microbiomes are critical environmental factors influencing the occurrence and quality formation of Ophiocordyceps sinensis, a valuable medicinal fungus endemic to the Qinghai-Tibet Plateau. However, few studies have explored the relationship between mycosphere soil fungal communities and the quality characteristics of O. sinensis. This research aimed to systematically analyze the structural characteristics and diversity of fungal communities in mycosphere soils of O. sinensis from eight geographical regions using Illumina high-throughput sequencing, and compare the nucleoside contents in O. sinensis from the corresponding sites. Alpha diversity indices showed that soil samples from Yushu and Guoluo in Qinghai Province exhibited higher fungal richness and diversity compared to other regions, whereas samples from Qamdo in Tibet showed the lowest diversity. Beta diversity analysis indicated significant differences in fungal community structure across various regions (R = 0.861, p = 0.001). At the phylum level, Ascomycota overwhelmingly dominated throughout all mycosphere soils of O. sinensis (96.30–99.88%), followed by Mortierellomycetes (0.25–2.25%). Network analysis revealed that Ophiocordyceps emerged as the core taxon in the mycosphere fungal communities, suggesting its central role in shaping the structure of the fungal networks. Additionally, O. sinensis from Yushu contained the highest total nucleoside content, indicating that the accumulation of nucleosides in O. sinensis may be affected by the composition of mycosphere soil fungi. Furthermore, correlation analysis indicated a significant positive relationship between several mycosphere fungal abundances and nucleoside accumulation in O. sinensis, such as Naganishia, Acicuseptoria, Nectria, Serendipita, and Humicola. These findings would provide a theoretical foundation for improving artificial cultivation strategies of O. sinensis. Full article

Physiographic, geographic, and environmental gradients influence the development of plant communities. This study assessed how environmental gradients affect riparian vegetation along the River Panjkora, aiming to find relationships between vegetation and abiotic factors through indicator species analysis. Vegetation was sampled using the quadrat method (1 × 1 m² for herbs, 5 × 5 m² for shrubs, 10 × 10 m² for trees), and soil samples were analyzed for edaphic variables. Indicator species and ordination analyses were performed using PCORD (version 5) and CANOCO (version 4.5) software to understand species diversity. Detrended correspondence analysis (DCA) and canonical correspondence analysis (CCA) identified species patterns and their links to environmental factors. A total of 216 plant species were recorded across seven stations, grouped into five communities. Community 01, Melia azedarach, Punica granatum, and Asparagus racemosus, are affected by Cr, p ≤ 0.03; Fe, p ≤ 0.01; Zn, p ≤ 0.04; and Mg, p = 0.03. On the other hand, Community 02, Populus alba, Debregeasia saeneb, and Youngia japonica, are controlled by Co, p = 0.01; pH, p = 0.03; Cd, p = 0.04; EC, p = 0.03; and TDSs, p = 0.03. The third community, with indicator species Pinus roxburghii, Rydingia limbata, and Cheilanthes pteridioides, is strongly influenced by Cr, p ≤ 0.05; Cu, p ≤ 0.03; TDSs, p = 0.02; and Zn, p = 0.03. Community 04, consisting of Ficus carica, Polygonum plebeium, and Avena sativa, is shaped by Na, p = 0.01; K, p ≤ 0.05; and Fe, p = 0.04. The fifth community, represented by Ficus palmata, Rosa multiflora, and Heliotropium europaeum, is influenced by pH, p ≤ 0.04 and Mn, p = 0.03. DCA displayed maximum gradient lengths of 6.443 (eigenvalue 0.742) on axis 1, 5.222 (0.662) on axis 2, 4.053 (0.600) on axis 3, and 4.791 (0.464) on axis 4. Soil pH, heavy metals (Cr, Fe, Zn, Mg, Co, Cd, Cu, Na, K, and Mn), EC, and TDSs were the main factors shaping community structure. The indicator species analysis is recommended to identify and conserve the rare species and native flora of a particular region. Full article

Peanut (Arachis hydropoaea L.) demonstrates a prominent adaptability to diverse soil types. However, the specific effects of soil types on peanut growth and bacterial communities remain elusive. This study conducted a thorough examination of the agronomic traits, the corresponding physicochemical properties, and bacterial structure of rhizosphere soil in acidic (AT), neutral (NT), and saline–alkali (ST) soils, elucidating the internal relationship between soil type and peanut yield. Our results showed that different soil types exhibited significant differences in peanut yield, with ST demonstrating the lowest yield per plant, showing an 85.05% reduction compared to NT. Furthermore, available phosphorus content, urease, and invertase activities were substantially reduced in both ST and AT, particularly in ST by 95.35%, 38.57%, and 62.54%, respectively. Meanwhile, metagenomic sequencing unveiled a notable decline in Bradyrhizobium and Streptomyces in these soils, which is crucial for soil improvement. Further metabolic pathway analysis revealed that the reduction in pathways related to soil remediation, fertility improvement, and stress response in AT and ST may lead to slower peanut growth. In conclusion, peanuts cultivated in acidic and saline–alkali soils can increase yield via implementing soil management practices such as improving soil quality and refining micro-environments. Our study provides practical applications for enhancing peanut yield in low- to medium-yield fields. Full article

In this study, we investigated the changes in the communities of arbuscular mycorrhizal fungi (AMF) and their driving factors across eight vegetation succession stages in the Sanjiang Plain, Northeast China, original natural wetland (NW), wetland edge (EW), shrub-invaded wetland (IW), shrub-dominated wetland (DW), young-Betula forest (YB), mature-Betula forest (MB), Populus and Betula mixed forest (PB), and conifer forest (CF), using Illumina MiSeq sequencing. As this research has revealed, significant differences exist in soil physicochemical indicators, including moisture content (MC), pH, soil organic carbon (SOC), total nitrogen (TN), available nitrogen (AN), total phosphorus (TP), and available phosphorus (AP). As vegetation succession progresses, the diversity and structure of AMF communities also undergo changes, with the Simpson diversity index being highest in coniferous forests (CF) and the Abundance-based Coverage Estimator (ACE) and Chao1 indices being elevated in shrub-dominated wetlands (PB). Non-metric multidimensional scaling (NMDS) analysis reveals distinct differences in AMF communities across various succession stages. Furthermore, stacked bar charts indicate that the genus Glomus dominates in most wetland and forest succession stages but is nearly absent in CF, where it is replaced by the genus Paraglomus. Canonical correspondence analysis (CCA) demonstrates that SOC has a more significant impact on AMF communities during the EW stage of succession, while AP and TP exert greater influence during the CF stage as well as the MB and YB stages. AN, on the other hand, plays a more prominent role in shaping AMF communities during the IW and NW stages. PICRUSt2 predictions reveal that enzymes such as alcohol dehydrogenase and L-aminoadipate-semialdehyde dehydrogenase are most abundant in YB, whereas pathways like 4-amino-2-methyl-5-diphosphomethylpyrimidine biosynthesis are most enriched in IW. These findings uncover the close interplay between soil physicochemical properties and AMF community dynamics, aiming to deepen our understanding of the relationships among soil physicochemical properties, AMF community changes, and succession dynamics in wetland and forest ecosystems. Full article

This study investigated soil fungal biodiversity in wheat-based crop rotation systems on Chernozem soil within the Pannonian Basin, focusing on the effects of tillage, crop rotation, and soil properties. Over three years, soil samples from ten plots were analyzed, revealing significant fungal diversity with Shannon–Wiener diversity indices ranging from 1.90 in monoculture systems to 2.38 in a fertilized two-year crop rotation. Dominant fungi, including Fusarium oxysporum, Penicillium sp., and Aspergillus sp., showed distinct preferences for soil conditions such as pH and organic matter (OM). Conservation tillage significantly enhanced fungal diversity and richness, with the highest diversity observed in a three-year crop rotation system incorporating cover crops, which achieved an average winter wheat yield of 7.0 t ha⁻¹—47% higher than unfertilized monoculture systems. Increased OM and nitrogen levels in these systems correlated with greater fungal abundance and diversity. Canonical correspondence analysis revealed strong relationships between fungal communities and soil properties, particularly pH and calcium carbonate content. These findings highlight the importance of tailored crop rotation and tillage strategies to improve soil health, enhance microbial biodiversity, and boost agricultural sustainability in temperate climates, providing valuable insights for mitigating the impacts of intensive farming and climate change. Full article

Indonesia is known for its incredible diversity of insects. Being ectothermic, insects are influenced by environmental factors. The relationship between insect diversity and the environment can be understood using multivariate analysis. The Paseh District in Sumedang Regency has various land uses, including gardens, rice fields, and plantations. Changes in land use due to the construction of the Cisumdawu Toll Road can impact environmental factors, such as soil quality, microclimate, and water availability, which are critical for sustaining diverse insect communities. Similarly, changes in vegetation cover can alter temperature and humidity levels, impacting terrestrial insects adapted to specific climatic conditions. This study aims to gather information on the relationship between insect diversity and environmental factors in different land use types in the Paseh District. A preliminary survey was carried out to record land use types and determine sampling locations. An intensive survey was done to collect and identify flying insect samples, as well as to measure the environmental factors. The results were analyzed using the Shannon–Wiener Diversity Index (H’), Evenness Index (E’), Simpson’s Diversity Index (C), and Canonical Correspondence Analysis (CCA). The study found 115 species of flying insects, with mixed gardens having the highest diversity. The CCA results showed that temperature strongly and positively correlated with insect diversity across all land uses, while wind speed correlated positively with insect diversity in gardens. Altitude correlated negatively with insect diversity in mixed gardens but positively in rice fields. Humidity had a strong positive correlation with insect diversity in other land uses. This research is important for understanding how land use types and environmental factors influence flying insect diversity, which is crucial for conserving biodiversity and maintaining essential ecosystem services such as pollination and pest control. Its impact lies in providing scientific data to guide sustainable land management practices, support agricultural productivity, and inform policies for biodiversity conservation in the Paseh District and similar regions. Full article

In the present study, the relationship between the microbial community and heavy metal content of soil was analyzed based on 16S rRNA gene high-throughput sequencing, in order to screen the corresponding heavy metal-resistant bacteria in a copper mine waste dump and adjacent shrubbery. Approximately 22 phyla, 57 classes, 128 orders, 173 families, 263 genera, 433 species, and 954 OUTs obtained from soil sample species annotation indicated the Spearman relevance analysis at the phylum level. Specifically, Gemmatimonadota is positively correlated with arsenic (As); Patescibacteria is positively correlated with arsenic (As), copper (Cu), and cadmium (Cd); Proteobacteria is positively correlated with chromium (Cr); and Acidobacteriota is positively correlated with cadmium (Cd), respectively. Meanwhile, at the genus level, Acidibacter is positively correlated with arsenic (As); norank_f__LWQ8, norank_f__Gemmataceae, and Bryobacter are positively correlated with cadmium (Cd); Acidiphilium and Conexiactor are positively correlated with Zinc (Zn); norank_f__norank_o__IMCC26256 is positively correlated with nickel (Ni); norank_f__norank_o__norank_c__AD3 is positively correlated with manganese (Mn), and nickel (Ni); and Alicyclobacillus and unclassified_f__Acidiferobactereae are positively correlated with chromium (Cr). These bacterial flora are significantly and positively related to the resistance of heavy metals, which provides a promising reference for the development of in situ remediation of heavy metal pollution in mines. Full article