Institute of Forest Ecology, Environment and Protection

The teak defoliator, Hyblaea puera, is a major pest damaging teak plantations and mangrove ecosystems. The high reproductive and dispersal capacities of this pest often lead to sudden and explosive outbreaks, posing challenges for its control. Genomic insights into this pest could help to elucidate its ecological adaptation and inform effective management strategies. Here, a high-quality genome of H. puera was assembled using integrated Illumina, PacBio HiFi, and Hi-C sequencing data. The final chromosome assembly is 394.93 Mb with a contig N50 of 11.49 Mb. A total of 96.97% of assembled sequences were anchored to 31 pseudo-chromosomes. Approximately 26.64% of the genome sequences comprise repetitive elements. Genome annotation identified 15,364 protein-coding genes, of which 86.79% (13,334) were functionally characterized. The completeness of the assembled genome was estimated to be 97.73% using BUSCO. This high-quality genome provides valuable resources for understanding the ecological adaptation and developing control strategies of H. puera.

Abstract Soil microorganisms are central to soil nutrient cycle by mediating organic matter decomposition and nutrient transformation. However, how changes in their physical and chemical environment across developmental stages of forest plantations accompanied by influence of the metabolic activity and nutrient use efficiency of rhizosphere microbes, and consequently, soil nutrient dynamics, remains poorly understood. We investigated rhizosphere soil microbial carbon and nitrogen use efficiencies (CUE and NUE) in subtropical Pinus massoniana plantations across 5, 9, 19, 29 and 35 years, for both growing and non‐growing seasons. Soil microbial CUE and NUE were consistently higher in the non‐growing season than in the growing season, likely due to higher nitrogen and lower carbon (C) content in litter and total potassium (K) concentration, which altered microbial substrate availability. Across stand development, CUE and NUE followed a pattern of initial increase, subsequent decline and later recovery. During the growing season, changes in CUE were mainly positively influenced by litter N content, whereas in the non‐growing season, CUE was positively associated with rhizosphere soil total K concentration. These shifts in soil CUE and NUE across stand development stages were further linked to changes in enzyme activities, with β‐glucosidase and peroxidase negatively associated with CUE and leucine aminopeptidase positively associated with NUE. Across stand ages, both CUE and NUE followed a non‐linear trajectory, suggesting complex interactions between litter inputs and rhizosphere available nutrient over time. Synthesis and applications . Microbial nutrient processing is strongly shaped by seasonal stoichiometric conditions and enzyme‐mediated substrate decomposition. This highlights the importance of considering seasonal and developmental stage‐specific management to optimize microbial function for improved forest productivity and carbon storage.

Abstract Leguminous green mulching (LGM) enhances soil biochemical properties and ecosystem functions of orchards, yet the underlying mechanisms remain poorly understood. To address this, we compared three mulching regimes—clean tillage, 4‐year mulching, and 8‐year mulching—to examine the response of soil microbial metabolic limitation and ecosystem multifunctionality (EMF) to LGM. Results showed that soil carbon (C), nitrogen (N) and phosphorus (P) contents, corresponding enzyme activities, and EMF all increased significantly with mulching duration but decreased with soil depth. In topsoil, 8‐year mulching achieved the highest EMF during the seeding‐fruit maturity stage (2.04), followed by the withering‐fruit swelling (WFS) stage (2.00). Microbial C limitation consistently declined with mulching age, while P limitation fluctuated across growth stages and mulching treatments. Compared with clean tillage, 8‐year mulching reduced microbial C limitation by 6.69%–45.02% and P limitation by 1.59%–9.47%. Partial least squares structural equation modeling indicated that EMF was driven directly by C‐ and N‐acquiring enzyme activities and indirectly by C and N nutrient pools. Among these, C‐acquiring enzyme activity (path coefficient: 0.42) exerted the strongest synergistic effect during the WFS stage. Collectively, prolonged LGM enhanced EMF by alleviating microbial nutrient constraints, with the greatest benefits observed in topsoil and during the WFS period. These findings provide multi‐temporal and spatial evidence that LGM regulates soil nutrient supply and cycling, offering a basis for more refined and targeted orchard management strategies.

<strong class="journal-contentHeaderColor">Abstract.</strong> Precise monitoring of key forest soil properties is crucial for addressing global challenges like carbon sequestration and soil acidification. However, existing national soil maps, primarily derived from comprehensive ecosystem samples, inadequately represent the distinct characteristics and high spatial heterogeneity of China's vast and diverse forest ecosystems. To bridge this gap, we present the first high-resolution (90-m), forest-specific maps of soil bulk density (BD) and pH across China. Leveraging 4,356 forest soil profiles collected through extensive field surveys and 41 environmental covariates within an optimized Quantile Regression Forests (QRF) framework incorporating forward recursive feature selection (FRFS), we generated wall-to-wall predictions for five standardized depth intervals (0&ndash;5, 5&ndash;15, 15&ndash;30, 30&ndash;60, 60&ndash;100 cm). Model performance, assessed through 10-fold cross-validation (CV) and independent validation (IV), achieved model efficiency coefficients (MEC) ranging from 0.78 to 0.89 (CV) and 0.60 to 0.66 (IV) for bulk density (BD), and from 0.83 to 0.87 (CV) and 0.71 to 0.81 (IV) for pH, indicating the product's strong capability to capture the spatial variability of forest soil properties across China. The 90-m resolution BD and pH maps contribute to the GlobalSoilMap initiative and provide forest-specific inputs for regional Earth system and land surface models. These products advance the quantification of soil acidification processes and provide critical baseline data for estimating forest soil carbon stocks across China. The dataset is available at <a href="https://doi.org/10.57760/sciencedb.25375">https://doi.org/10.57760/sciencedb.25375</a>.

Using the MaxEnt model with climatic, topographical, soil, and human activity factors, this study predicted suitable habitats for eight Rhodiola species in the Qinghai-Tibet Plateau (QTP) and analyzed conservation gaps via ArcGIS overlay analysis. Models demonstrated high accuracy, with area under the receiver operating characteristic curve (AUC) values ranging from 0.88 to 0.99. Human activities dominated habitat suitability for most species (contribution: 37.0%-76.4%), except R. atsaensis (RA), driven by climate (38.9%) and topography (32.8%). Current suitable habitats varied widely, with RA occupying the largest area (1.69 × 106 km2), and R. sacra (RS) the smallest (5.61 × 104 km2). Future climate scenarios show seven Rhodiola species (except RS) will expand, and all have increasing highly suitable areas. R. smithii and R. tibetica expand most; RS only expands under SSP1-2.6 in 2090. Current nature reserve coverage protects 33.42% of the suitable habitats for Rhodiola species on the plateau, with national reserves accounting for 28.13% and other protected areas (PAs) only 5.29%. Protection efficiency varies significantly among species. RA has the highest protection rate (35.38%), while R. bupleuroides and RS show the lowest (~20%). National reserves exhibit protection rates of 13.11%-29.98% for suitable habitats, surpassing other-level reserves (2.1%-8.27%). Conservation gaps are concentrated in ecologically sensitive zones such as the Hotan-Ngari, Lhasa, and eastern Chamdo. Strikingly, protection of high and medium habitats remains extremely low (5.12%). The findings provide critical insights for prioritizing strategic conservation efforts and optimizing PA networks across the QTP, thereby addressing the current protection gaps and enhancing ecological connectivity.

Introduction Artificial Elevated atmospheric nitrogen (N) deposition enriches reactive N in terrestrial ecosystems, where soil organic nitrogen (SON) dominates the soil N pool. However, the composition of SON and its relationship with inorganic N remain poorly understood. Methods To assess the impact of N deposition on soil N dynamics under climate change, this study investigated a Quercus variabilis plantation in the Three Gorges reservoir area subjected to three years of N addition (0, 30, 60, 90 kg N ha -1 yr -1 ). Soil samples were sieved into four aggregate size fractions (8000–2000 μm, 2000–1000 μm, 1000–250 μm, &amp;lt;250 μm). Levels of acid-hydrolyzable nitrogen (AHN) and rates of net N mineralization (Nmin) and nitrification were measured. Results Net nitrification (0.30–3.42 mg N kg -1 ) comprised over 80% of net Nmin within aggregates.Net N transformation rates peaked in the finest soil aggregates (&amp;lt;250 μm), which exhibited the lowest available phosphorus (P) levels. These rates were positively correlated with N addition and microbial biomass. Total N and net N transformation increased with N input, while available P decreased. Multiple stepwise regression identified acid-hydrolyzable amino acid N, amino sugar N, and total AHN as effective predictors of net N transformation rates. Discussion Enhanced N inputs significantly stimulated the conversion of SON into inorganic N, thereby amplifying soil N supply capacity. Nonetheless, prolonged N deposition raises concerns regarding potential phosphorus and soil organic matter loss.