2026-10-13T20:08:36Z https://api.figshare.com/v2/oai

oai:figshare.com:article/33993019 2026-09-25T05:31:21Z category_87 portal_316 item_type_3 month_year_09_2026

Supplementary file 1_Strip thinning and filling reduces litter humus carbon loss in Cupressus funebris plantations: relative contributions of microclimate, litter substrate and microbial biomass.docx Jiaping Yang (2184471) Qing Dong (5624) Qiang Wang (32383) Honglin Yang (559520) Yulian Yang (5012561) Qinggui Wu (5012558) Soil Science biogeochemical process environmental regulators foliar litter decomposition litter humus retention plantation ecosystem Introduction<p>Alkaline-extractable litter humus carbon constitutes the precursor pool of soil organic matter (SOM) generated via litter biotransformation. However, few systematic studies have explored litter humification responses to diverse management practices in subtropical Cupressus funebris (cypress) plantations.</p>Methods<p>We conducted a 1,277-day in situ litterbag decomposition experiment encompassing four stand treatments: an unmanaged pure plantation (UMP, control), artificial forest gap creation (AFG), strip thinning and filling (STF), and density-based ecological thinning (ETD). We quantified four core humification metrics across arbor, shrub, herb, and field-mass-proportioned mixed litter: alkaline-extractable humus carbon (HUc), net relative change in humus carbon (ΔHUc), humification degree (HD), and cumulative intensity of humification (HCI).</p>Results<p>The exploratory pairwise contrasts suggested that STF exhibited relatively higher HUc and HD together with less‑negative ΔHUc compared with AFG (p < 0.05); no significant differences in HUc and ΔHUc were observed between STF versus UMP, or STF versus ETD. Shrub litter exhibited markedly greater HUc and HD than arbor, herb, and mixed litter (p < 0.05). Hierarchical partitioning (HP) revealed litter substrate as the dominant factor for humification variation, accounting for 64.59 %, 71.15 %, 42.69 %, and 46.60 % of explained variance in UMP, AFG, STF, and ETD, respectively; climatic variables also exerted notable regulatory effects, particularly within STF stands. Further partial least squares path modeling (PLS‑PM) demonstrated that climatic conditions exerted strong, statistically significant direct negative effects on litter humification in all stands, even though its relative explained variance from HP was moderate. Among managed stands, STF yielded a negative point-estimate for the direct microbial-to-humification path (β = -0.422, bootstrap 95% CI -0.485 to 0.444, includes zero). By contrast, the unmanaged UMP stand had a significant positive microbial direct effect on litter humification. Significant negative direct litter‑substrate effects on humification were observed in UMP, AFG and ETD, whereas this substrate path was non-significant in STF.</p>Discussion<p>Overall, STF effectively mitigated litter humus carbon loss, and its humus-preserving capacity could be further enhanced by promoting understory shrub recruitment. This study provides empirical evidence for optimizing management practices to conserve litter humus in low-yield subtropical cypress plantations, and replicated multi-stand experiments are needed for broader generalization.</p> 2026-09-25T05:31:21Z Dataset Dataset 10.3389/fsoil.2026.1929672.s001 https://figshare.com/articles/dataset/Supplementary_file_1_Strip_thinning_and_filling_reduces_litter_humus_carbon_loss_in_Cupressus_funebris_plantations_relative_contributions_of_microclimate_litter_substrate_and_microbial_biomass_docx/33993019 CC BY 4.0