Effects of Nitrogen Addition on Soil Aggregate Stability and Mycorrhizal Morphological Characteristics: Differential Responses of Arbuscular Mycorrhizal and Ectomycorrhizal Fungi

Forests, Journal Year: 2025, Volume and Issue: 16(2), P. 282 - 282

Published: Feb. 6, 2025

Soil aggregate stability plays a pivotal role in ecosystem functioning and carbon sequestration. Nitrogen deposition influences drives differential responses AM ECM fungi, yet the underlying mechanisms remain unclear. This study aimed to determine how N addition soil aggregation, mycorrhizal morphological characteristics, organic (SOC) across two types. A temperate forest experiment was conducted northeastern China using 12 plots subjected four treatments (control, low, medium, high). properties, traits, distributions were quantified. Relationships examined via correlation analyses, random models, structural equation modeling. enrichment substantially increased SOC water content, enhancing proportion of large aggregates (4–8 mm) elevating mean weight diameter (MWD) geometric (GMD), critical indicators stability. fungi exhibited stronger response than ECM, reflected greater hyphal development accumulation. content correlated positively with stability, whereas pH showed negative association. inputs enhance by promoting retention, demonstrating heightened sensitivity addition. These findings emphasize integral dynamics shaping stabilization under increasing deposition.

Language: Английский

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The Complex Co-Occurrence Network Under N Deposition Resulting in the Change of Soil Bacterial Structure and the Decrease of Bacterial Abundance in Subtropical Quercus aquifolioides Forest

Forests, Journal Year: 2025, Volume and Issue: 16(3), P. 481 - 481

Published: March 10, 2025

Atmospheric nitrogen deposition has a profound impact on soil (N) cycling within terrestrial ecosystems, altering the microbial community structure and composition. To investigate how impacts communities across different seasons, this study focused mature subtropical Quercus aquifolioides forest. Four treatments were applied, high-throughput sequencing was utilized to analyze composition changes during dry wet seasons. Additionally, explored interactions between nutrients, communities, treatments. Following four years of supplementation, results revealed that: (1) Soil chemistry enzyme activity shifted significantly due combined effects addition seasonal variations. A marked reduction in pH indicated substantial acidification, although season’s increased moisture mitigated these effects. (2) Fungal richness diversity more sensitive than bacterial diversity. (3) During season, caused notable shifts composition, with elevation relative proportion fungal genus Sebacina (↑112.68%) under MN treatment. (4) Nitrogen affected co-occurrence network complexity bacteria fungi season-dependent manner. decreased while increased. In contrast, season showed an complexity. (5) The remained stable seasons treatments, whereas significant differences after addition. Environmental factors influencing structures varied depending water conditions. These findings provide insights into forest management remediation strategies response future atmospheric deposition.

Language: Английский

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Differentiated response mechanisms of soil microbial communities to nitrogen deposition driven by tree species variations in subtropical planted forests

Frontiers in Microbiology, Journal Year: 2025, Volume and Issue: 16

Published: March 12, 2025

Introduction The increasing rate of atmospheric nitrogen deposition has severely affected the structure and function these ecosystems. Although is globally, responses soil microbial communities in subtropical planted forests remain inadequately studied. Methods In this study, a four-year experimental simulation was conducted to assess impacts varying levels (CK: 0 g·N·m −2 ·a −1 ; N10: 10 N20: 20 N25: 25 ) on two tree species, Pinus yunnanensis Franch. armandii High-throughput sequencing performed using Illumina MiSeq platform. Statistical analyses, including analysis variance (ANOVA), linear mixed-effects models, principal coordinate (PCoA), similarity (ANOSIM), redundancy (RDA), random forest analysis, structural equation modeling (SEM), were used examine short-term nutrients, bacterial communities, fungal community structures deposition. Results discussion results showed that species differences led variations properties between forests, particularly significant increase pH P. decrease forests. Nitrogen addition did not significantly affect diversity either or soils; however, type had impact diversity. relative abundance specific both types, altering Franch while no changes observed type. Furthermore, increased network complexity decreasing Structural indicated regulates types by modifying availability. Purpose significance These findings provide insights into potential long-term ecosystems offer theoretical basis for sustainable management regulatory practices.

Language: Английский

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The Effect of Acid Rain and Understory Vegetation Removal on the Biological Activity of the Soils of the Cinnamomum camphora (Linn) Presl Plantation

Forests, Journal Year: 2025, Volume and Issue: 16(3), P. 525 - 525

Published: March 16, 2025

Acid rain and understory vegetation removal are critical drivers altering soil ecosystem alterations. However, the mechanisms by which these factors influence moisture dynamics, nutrient availability, microbially mediated enzyme activities remain insufficiently elucidated. This study investigated impacts of simulated acid on properties, activities, microbial community in a subtropical Cinnamomum camphor (Linn) Presl plantation. The results indicated that significantly decreased organic carbon (SOC) while concurrently elevating C-acquiring C limitation. Understory markedly reduced moisture, N- P-acquiring activities. Additionally, increased bacterial diversity, but fungal diversity. Moreover, both enhanced deterministic processes destabilized shifting generalists toward specialists, had no significant effect structure. Partial least squares path modeling revealed stability loss intensified limitation, regulated P Collectively, findings highlighted role buffering microclimate cycling, demonstrated communities more responsive to than communities. provides insights into anthropogenic disturbances alter ecological functions plantations, emphasizing need for integrated forest management strategies conserve manage ecosystems plantations.

Language: Английский

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Increased Soil Moisture in the Wet Season Alleviates the Negative Effects of Nitrogen Deposition on Soil Microbial Communities in Subtropical Evergreen Broad-Leaved Forest

Forests, Journal Year: 2024, Volume and Issue: 15(8), P. 1473 - 1473

Published: Aug. 21, 2024

The rapid increase in reactive nitrogen (N) released into the environment by human activities has notably altered structure and composition of forest soil microbial communities (SMCs), profoundly impacting N cycle terrestrial ecosystems. However, response microorganisms to addition different seasons is not clear. This study delved how SMCs a subtropical region central Yunnan, China, specifically an evergreen broad-leaved (EBLF), respond deposition during both dry wet seasons. Through high-throughput sequencing, we assessed under varying treatments across seasons, examining their interplay with chemical properties, enzyme activities, community responses. findings revealed significant outcomes following four years EBLF: (1) Significant changes were observed due interaction between seasonal changes. Soil pH significantly decreased, indicating increased acidification, particularly season. Increased moisture season mitigated acidification. (2) In season, led decrease richness diversity. diversity, alleviating downward trend (3) impacted bacterial fungal communities. Dominant genera sensitive addition. (4) Seasonal structures. properties influenced structure. differences moisture, key environmental factors that regulate have changed serves as foundation for understanding impacts EBLF ecosystems regions, offering valuable insights scientific management ecological resources amidst global change trends.

Language: Английский

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Changes of bacterial versus fungal community composition along a forest degradation gradient of logged-over tropical rain forests, and their consequences on soil enzyme activities in Malaysian Borneo

Plant and Soil, Journal Year: 2024, Volume and Issue: unknown

Published: Sept. 13, 2024

Abstract Background and aim Soil bacterial fungal communities play different but mutually interrelated roles in releasing enzymes that catalyze organic matter decomposition. In Malaysian Borneo, decreasing litter inputs caused by forest degradation lead to reductions soil carbon (SOC) C/N ratio. Enzyme activities also decrease with degradation. However, it is unclear if/how changes microbial community compositions affect enzymes, despite their importance ecosystem processes. We investigated how reduced SOC substrate affects further influences enzyme during Methods used 16S ITS amplicon sequencing ergosterol extraction derive absolute relative abundances. A principal coordinate analysis was performed on abundances analyze patterns of compositions. Structural equation modeling (SEM) conducted investigate via Results Fungal composition shifted more distinctly than along the gradient. SEM suggested influenced compositions, while affected acid phosphatase, β-glucosidase, leucine aminopeptidase. Conclusion Changes may be due responses phyla changing quality bulk input Variations subsequently induced activities. By contrast, did not change because labile substrates available throughout course, particularly such being supplied as decomposition by-products.

Language: Английский

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