编者按

Cathaya argyrophylla, a National Class I protected Plant and an endemic “living fossil” species in China, has fewer than 2,400 wild individuals. Over the past 40 years, extensive research have been conducted on its biological characteristics, genetic diversity, habitat requirements, and conservation strategies. However, C. argyrophylla wild populations continue to decline, presenting a severe conservation challenge. We reviewed the research progress on C. argyrophylla, analyzing its endangered status from aspects such as growth and reproduction traits, geographical distribution, and population dynamics. Additionally, we conducted surveys of fourteen wild populations in 2023 and found that C. argyrophylla seedlings are scarce, juvenile tree mortality rate is high, and population structure indicates a declining trend. This suggests that natural regeneration of C. argyrophylla is hindered, and the current conservation measures are insufficient to reverse the decline. Although progress has been made in seedling cultivation and ex situ conservation, there is still a significant gap in protecting the species' genetic diversity, which requires urgent attention and improvement. Future research and conservation efforts should integrate multiple disciplines and apply new technologies, particularly high-throughput sequencing for conservation genomics, to reveal the endangerment mechanisms and adaptive potential of C. argyrophylla. Additionally, integration of multi-source remote sensing technologies is necessary to monitor population dynamics and habitat changes, which could provide more accurate data to support conservation of C. argyrophylla.

Endangered species protection and wild rehabilitation is a major issue facing mankind, which requires more scientific and theoretical guidance and application practice from a multidisciplinary perspective and multi-type technology platform, so as to better serve the biodiversity protection, product output and sustainable development of local characteristic ecosystems. Focusing on coastal endangered wild tree species in Zhejiang Province, China, this paper summarizes the past research and achievements on endangered tree species, the existing problems and shortcomings, with an overarching aim to provide research programs for the protection and restoration of endangered tree species on islands in the future. We proposed that future research objectives would be the construction of near-natural habitats and the construction of wild return populations. Combining theories and technologies related to global change ecology, dendrochronology, microbial ecology, population ge-netics, bioconservation engineering and other disciplines, from the perspective of multi-scale genes, cells, individuals, commu-nities, and ecosystems, we would like to develop a series of integrated technologies and equipment, such as historical original habitat and near-natural habitat reconstruction, molecular breeding, microbial rejuvenation, extreme climate early warning and artificial intelligence monitoring, application demonstration base construction. The expected results can provide risk early warning for the coastal endangered tree species and their typical ecosystems to cope with extreme climate and provide common technologies and demonstration cases for biodiversity protection.

Aims Pinus squamata, is a critically endangered species endemic to China, found only in Qiaojia County, Yunnan Province. It faces significant challenges such as fragile habitats and difficulties in population recovery. Fungal communities play a vital role in the population maintenance and ecological adaptation of endangered plants. However, studies on the fungal community characteristics within the roots and rhizosphere of P. squamata are currently insufficient. Methods This study used in-situ sampling and high-throughput sequencing to analyze the fungal community structures and geographical differentiation patterns of wild and cultivated populations of P. squamata. Additionally, it compared the fungal community structures of Pinus squamata with those of its neighboring plant species. Important findings (1) There are significant differences in the fungal community structures within the roots and rhizosphere between the wild and cultivated populations of P. squamata. The fungal diversity in the wild populations is lower than that of the cultivated population. (2) In the wild populations, the fungal communities differ significantly between individuals in the west-slope and east-slope populations. (3) Ectomycorrhizal (ECM) fungi, such as species from the genera Sebacina, Russula, and Xanthoconium, dominate the root systems of Pinus squamata. Individuals in the west-slope population, which inhabit nutrient-poor soils, exhibit greater dependence on ECM fungi. (4) P. squamata shares some ECM fungi with neighboring tree species, highlighting the cooperative role of mycorrhizal fungal networks in resource sharing and ecological stability. This study reveals both abiotic and biotic factors influencing the fungal communities of P. squamata. Results of this study suggest that conservation efforts should combine inoculation with ectomycorrhizal fungi and improvement of the seedling soil to restore critical ectomycorrhizal networks, thereby promoting the vision of integrated recovery of the “pine-fungus” system.

Aims The IUCN Red List provides basis to biodiversity conservation designation. The Red List Index (RLI) derived from the results of Red List assessment is an indicator for the status of species and specific taxonomic groups at global, national, regional scales. Based on the IUCN global assessment data, this study aims to analyze the RLI of Chinese higher plants. Methods The RLI can be calculated based on either national or global assessment data. Chinese Red List Index based on national assessment data (nRLI) for higher plants has been reported. Following the IUCN assessment framework, through the partition of species Extent of Occurrence (EOO) of China and the rest of the world, this study calculated Chinese higher plant Red List Index based on global assessment data (gRLI). And then compared Chinese higher plant gRLI with the results from the Biodiversity Indicators Partnership (BIP), which relied only on a representative subset of Cycads to calculate a nation’s gRLI. Important findings The Chinese higher plant gRLI, with equal steps method, is 0.9467, 0.9082, and 0.5401 for the source data of IUCN assessments, IUCN and Chinese endemic species assessments, and solely Cycas, respectively. The BIP approach underestimates Chinese gRLI for higher plants, suggesting taxonomical bias. This highlights the importance of utilizing as much reliable data as possible for a more precise result of gRLI. By calculating Chinese higher plant gRLI which is comparable to that of other countries, this study provides essential baseline data to support China's international commitments and conservation efforts for various international conventions about biodiversity.

Aims The rapid fluctuations of climate are increasingly altering the fate of species, exacerbating their vulnerability, leading to the loss of genetic diversity in many species, and even pushing some to the brink of extinction. Relict plants, having survived extreme climate changes since the Cenozoic era, carry a wealth of genetic information related to environmental adaptation. Investigating the genetic basis of their population-level environmental adaptation and their potential to cope with future climate change can provide valuable insights for biodiversity conservation. Methods In this study, restriction site-associated DNA sequencing (RAD-seq) was performed on 122 individuals from 18 populations of Pterocarya hupehensis, which is a Cenozoic relict plant distributed around the Sichuan Basin in China. Then, the ecological adaptation and genetic vulnerability of P. hupehensis were studied by landscape genomics. First, we use a latent factor mixed model (LFMM) and Pcadapt to detect selected sites. Second, a Mantel test based on linear models, redundancy analysis (RDA), gradient forest (GF), and generalized dissimilarity modelling (GDM) were used to investigate the response patterns of genetic variation to environmental gradients. Finally, based on the risk of non-adaptedness (RONA), the vulnerability of the P. hupehensis was predicted for the SSP 245 and SSP585 scenarios in 2090. Important findings A total of 398 single nucleotide polymorphism loci (SNPs) were significantly associated with the six climatic factors (Isothermality, Minimum Temperature of Coldest Month, Temperature Annual Range, Mean Temperature of Wettest Quarter, Precipitation of Wettest Month, and Precipitation Seasonality). In addition, 177 of them were detected as selected SNPs. We found that Precipitation Seasonality was an important climatic factor affecting the genetic variation of P. hupehensis. A significant signal of isolation by environment (IBE) was detected, indicating that environmental factors account for more genetic variation than geographical factors. Under the SSP585 scenario in 2090, the genetic vulnerability of P. hupehensis was higher than that under SSP126 scenario. The Precipitation Seasonality has an important effect on the adaptative ability of the population in the northwest range of P. hupehensis. This study not only provides a theoretical foundation for the management and conservation strategies of vulnerable species in the face of future climate change, but also offers a new case study on how relict plants around Sichuan Basin may respond to future climate change.

Aims Nyphaea candida C. Presl, an endangered species endemic to Xinjiang and classified as a National Class II protected plant, faces high risks of extinction and requires urgent conservation efforts. The aim of this study is to reveal its reproductive characteristics and explore factors associated with endangered status from a reproductive biology perspective. Methods This study systematically investigated the flowering phenology, floral morphology, breeding sys-tem, pollination process, and seed germination characteristics of N. candida in natural populations. Important findings The flowering period lasts from May to September, with a single flower lifespan of ap-proximately four days, while the stigma remains receptive for only 1～2 days. Pollinators are mainly syrphid flies, though visitation frequency is low and easily affected by adverse weather conditions such as rain. Ex-perimental data suggest that N. candida follows a mixed mating system, predominantly outcrossing but also self-compatible, and depends on pollinators for successful reproduction. Seed viability is measured at 45.33±4.29%, yet germination rate under natural conditions is low (only 2.67±1.63%), restricted by seed coat barriers. The reproductive process of N. candida faces significant limitations due to its floral characteristics, pollination behavior, and seed germination challenges, notably with limited pollinator availability, low visita-tion frequency, and reduced seed viability. Environmental factors (e.g., rainy weather) further inhibit pollina-tion success, imposing substantial pollination constraints on this species. In unstable pollination environments, N. candida tends to adopt a spontaneous self-pollination strategy, which may lead to inbreeding depression and further increase its risk of endangerment.

Aims In order to understand the geographical distribution of threatened species of genus Epimedium in China, and to provide the basis for resource conservation and utilization. Methods The data of Chinese Virtual Herbarium (CVH), China National Specimen Information Infrastructure (NSII), the Royal Botanic Garden Edinburgh (E), Royal Botanic Gardens, Kew (K), Muséum National d'Histoire Naturelle (P) and Universitat Wien (WU) were used. And the specimens of Herbarium of Institute of Medicinal Botany, Chinese Academy of Medical Sciences (IMD), which is not included in the sharing platform but abundant in Epimedium specimens, were also examined. At the same time, combined with our field investigations and literature review, the specimen information of 25 species and 1 variety of Epimedium in China were systematically collected to verify the specimen identification and geographical distribution, and updated the endangered categories and criteria. Important findings A total of 1017 specimens of 428 numbers were examined, and only 666 specimens of 274 numbers (64.02%) were correctly identified. Nineteen taxa (73.08%) had found new distribution compared with the recorded of Flora of China. However, six species were currently known to be distributed only in the type locality. The three provinces with the highest abundance of threatened species were Sichuan (12 species), Hubei (7 species) and Guizhou (6 species and 1 variety). The endangered categories or criteria of 22 taxa were suggested to be adjusted. Epimedium enshiense B. L. Guo et Hsiao, E. reticulatum C. Y. Wu, E. fangii Stearn and E. elachyphyllum Stearn were suggested to be upgraded to Critically Endangered (CR). The endangered categories of E. flavum Stearn, E. glandulosopilosum H. R. Liang, E. mikinorii Stearn, E. sagittatum var. glabratum Ying, E. truncatum H. R. Liang and E. zhushanense K. F. Wu et S. X. Qian were suggested to be upgraded to Endangered (EN). Epimedium simplicifolium Ying and E. fargesii Franch. were respectively suggested to be downgraded from Critically Endangered (CR) and Endangered (EN) to Vulnerable (VU). For another 10 species, the endangered categories remained unchanged and only the criteria were adjusted. The main reasons for the endangered plants of Epimedium were narrow distribution, habitat decline and population decrease. Errors in the identification of specimens of threatened species of Epimedium were prominent. Most species of this genus were distributed in narrow areas and were highly threatened. Therefore, the protection of species diversity should be paid more attention. The?evaluation of endangered categories and criteria is a dynamic process that requires long-term monitoring and constant updating.

Aims Rhododendron liboense was a plant species with extremely small populations which distributed on top of limestone mountains, it has high ornamental and scientific research value. The habitat of it was fragile, and the wild population of it was rare, which urgently needs to be studied for conservation genetics. Methods This study focused on 43 individuals from three populations of R. liboense, using double digest restriction-site associated DNA sequencing technology (ddRAD-seq) to obtain single nucleotide polymorphism (SNP) data. The genetic diversity and structure of R. liboense population were analyzed, and historical population dynamics were inferred. Important findings The results showed that the genetic diversity of R. liboense was low (He = 0.139 62 ± 0.003 32, π = 0.157 64 ± 0.003 83), and the level of genetic differentiation between populations was moderate (FST = 0.075 8), The variation within the population (88.22%) is greater than the variation between populations (11.78%) . Structure analysis, PCA analysis, and cluster analysis were used to divide the three populations of R. liboense into two genetic groups. The analysis of population historical dynamics showed that the effective population size (Ne) of R. liboense had been continuously increasing since the last glacial period, which might be related to the gradual warming of the climate suitable for its survival. Based on the above research results and population status, it was recommended to divide the populations into two management units for on-site conservation, while strengthening research on artificial breeding techniques to assist in the ex-situ conservation and field return of R. liboense.

Abstract Aims In recent years, resources of Glycine soja had decreased dramatically under the human disturbance. This study aimed to reveal the resource recovery and position of Glycine soja in communities on abandoned farmland, evaluate its interspecific association with other species and the stability of the community, as well as provide a theoretical basis for resource conservation and community restoration of Glycine soja . Methods In this paper, quadrat method with 1 m×1 m was used on the herb communities on 3 abandoned farmlands near the river located in the suburbs of Shenyang city. The importance value, ecological niche width and the degree of ecological overlap, interspecific association of the major herbaceous in the communities and the stability of the community were analyzed. Important findings There were 65 species of herbaceous plants belonged to 20 families and 51 genera in the investigated community, among which annual plants accounted for 52.31 %. Glycine soja was the most dominant species in the community, with the highest frequency (97.18 %), coverage (49.75 % in average), importance value (33.28) and niche width (BL=101.92, BS=4.75). The resource use overlap Oik value (0.35) and niche similarity (0.30) between Glycine soja and Artemisia lancea were the largest, and the niche overlap between Glycine soja and Vigna minima was also large (Oik=0.34). χ2 test and AC results showed that there was a significant positive association between Glycine soja and Artemisia lancea, and a very significant negative association between Glycine soja and Humulus scandens. The correlation coefficient showed that Glycine soja had a positive association with Vigna minima, but very significant negative association with Setaria viridis, Persicaria orientalis and Echinochloa crusgalli. The overall niche overlap values of the important plants in the community were low (0~0.35). The VR and W values of the variance ratio test of the total association were 0.87 and 122.16, indicating that there was negative association among the major plants in the community. The results of χ2 test, association coefficient (AC), and Spearman rank correlation coefficient showed that there were mainly negative associations among species. The Euclidean distance between the coordinates of the intersection point and the coordinates of the stable point analyzed by M. Godron method was far, indicating that the community stability was relatively poor. However, the Euclidean distance of the community with a longer period of returning farmland to forest was closer than that of the community with a shorter period, suggesting that community stability increases with longer abandonment times.

Aims Salweenia wardii, a rare and endangered protected plant in China, is a extremely small population in the arid valleys of the Hengduan Mountainous. Ite habitat is fragile and severely fragmented, and systematic research on its community ecological adaptive mechanisms and conservation strategies remains lacking. Methods Based on literature and field sample surveys, we initially delineated the geographical distri-bution range of Salweenia wardii. Utilizing data from 18 survey plots collected between 2023 - 2024, we proposed a preliminary community classification scheme, accompanied by a detailed description of the community structure. Additionally, we also analyzed species composition in conjunction with data from 38 list quadrats obtained during the survey. Important findings The results showed that: (1) Salweenia wardii community was concentrated in Karuo District, Baju County, Luolong County and Chaya County of Chamdo City, and formed dominant communities in Karuo Town, Xiali Township, Qumba Township and Jiba Village, with distribution alti-tudes ranging from (3000) 3083 to 3657 (4400) m. (2) 74 vascular plants belonging to 28 families and 55 genera were recorded, mainly xerophytes in the families of Gramineae, Asteraceae, and Rosaceae. The life forms spectrum, dominated by deciduous shrubs and perennial herbs, along with the floristic charac-teristics featuring the coexistence of pan-tropical and north-temperate components, reflected their adaptive strategies to seasonal droughts and the evolutionary features of transitional zone in the Hengduan Mountains. (3) Based on variations in community structure and species composition, Salweenia wardii alliance could be classified into 6 association groups and 10 associations. (4) The population exhibited low natural regeneration capacity and relied on asexual reproduction for maintaice, necessitating urgent conservation measures. Our fingdings fill the gaps in the taxonomic study of Salweenia wardii and offers scientific basis and practical guidance for regiregional biodiversity conservation and ecosystems resto-ration.

Abstract Aims Litter quality plays an important role in regulating the magnitude and direction of soil priming effect. However, it remains unclear how the inputs of litter with different carbon to nitrogen ratios (C:N) affect soil priming effect. Methods Cunninghamia lanceolata seedlings were 13C-labeled. To obtain low and high C:N of C. lanceolata leaves, stems, and roots, one half of the C. lanceolata seedlings were fertilized and another half were unfertilized. The priming effect is quantified by the difference in CO2 emissions from native soil organic carbon (SOC) between soil amended with and without litter. Moreover, this research investigated the impacts of the input of low C:N and high C:N C. lanceolata leaves, stems, and roots on the soil priming effect and to clarify the mechanism via measuring soil microbial biomass, enzyme activities, and soil available nitrogen content. Important findings After 180 days of incubation, the input of C. lanceolata leaves induced a positive priming effect at the early stage of incubation. However, over the entire incubation period (180 days), it had no significant effect on SOC mineralization. The input of low C:N of C. lanceolata roots decreased SOC mineralization by 10.1% and induced a negative priming effect. However, the addition of C. lanceolata roots high C:N of as well as the C. lanceolata stems had no significant effect on SOC mineralization. Different C:N (high vs. low) of the same organ of C. lanceolata had no significant effect on soil priming effect. The additions of litter with different C:N did not significantly affect soil microbial biomass carbon and related C metabolic enzyme activities. The structural equation model showed that priming effect was mainly affected by 13C-microbial biomass carbon (MBC), soil available nitrogen, microbial biomass nitrogen (MBN) and β-glucosidase. These factors could explain 30%of the variation of priming effect. Moreover all factors (except for 13C-MBC) were negatively correlated with soil priming effect.

AimsShrublands is an indispensable part of estimating carbon density in terrestrial ecosystems, and the expansion of shrublands is considered as one of the key reasons leading to the increase of carbon density in terrestrial ecosystems in China, and yet there are great uncertainties in the carbon sink capacities of shrublands. Our objectives were to estimate the carbon density and distribution characteristics of common shrublands in North China. Methods The carbon density and distribution characteristics of two typical shrublands (Caragana jubata and Carpinus turczaninowii) in Dongling Mountain, Beijing, were measured based on the field investigation data and by employing allometric approaches. Important findings The results showed that the carbon density (427.59 t?hm-2) of C. jubatashrubland was significantly higher than that (178.19 t?hm-2) of the C. turczaninowii shrubland, in which the carbon storage of soil layer was the most (98.53%and 81.31%), and the carbon storage were 421.29 t?hm-2 and 144.89 t?hm-2, respectively. Soil organic carbon was enriched in the 0–50 cm soil layer, and showed a decreasing trend with increasing soil depth. The organic carbon density in different soil layers of the C. jubata shrubland is higher than that of the C. turczaninowii shrubland, mainly due to the lower temperature and smaller slope in the distribution area of the former, which is conducive to the accumulation of organic matter. The contribution of the shrub layer and the arbor-shrub layer to the carbon density of the entire ecosystem were relatively small (1.27% and 17.77%), with values of 5.44 and 31.69 t?hm-2, respectively. The carbon density of different organs in the arbor layer was in the order of trunk > root > branch > leaf, while the order of carbon density in the shrub layer was branch > root > leaf in both shrublands. Moreover, the carbon density of each organ in the shrub layer of C. jubata shrubland was significantly lower than that in the C. turczaninowii shrubland.The herbaceous layer and litter layer contributed the least to the total carbon density of C. jubata and C. turczaninowii shrublands (0.20% and 0.91%), with values of 0.86 and 1.62t?hm-2, respectively. The carbon density of the herbaceous layer(0.55 t?hm-2) in C. jubata shrubland was significantly higher than that (0.35 t?hm-2) in C. turczaninowii shrublands. Moreover, carbon density of the aboveground and underground parts of the herbaceous layer in C. jubata shrubland was similar, while in C. turczaninowii shrubland, the aboveground carbon density was significantly lower than that of the underground part. The carbon density of the litter layer (1.27 t?hm-2) in C. turczaninowii shrubland was significantly higher than that (0.31 t?hm-2) in C. jubata shrubland.

Aims Alpine shrublands are crucial for global carbon cycle due to their substantial soil carbon storage and sensitivity to global changes. Twig and leaf litter play a crucial role in terrestrial ecosystem carbon and nutrient cycling; however, comparative studies on their production and decomposition remain limited. This knowledge gap hinders accurate assessments of their contributions to soil carbon and nutrient cycling. Methods This study investigated the annual production, decomposition rates, and carbon and nitrogen retention of twig and leaf litter in an alpine shrubland ecosystem on the eastern margin of the Qinghai–Tibetan Plateau of China over a four-year period. Important findings Results found that: (1) Leaf litter production (138.94 g·m?2·a?1) was 4.41 times higher than twig litter production (31.48 g·m?2·a?1). Thus, leaf litter had a higher annual carbon and nitrogen inputs than twig litter. (2) Decomposition rate of twig litter (K = 0.356 a-1) was significantly slower than that of leaf litter (K = 0.522 a-1). The proportion of recalcitrant fraction of twig litter during decomposition was 4.86 times higher than that of leaf litter (0.287 vs. 0.059, respectively). (3) Nitrogen release patterns differed between twig and leaf litter: leaf litter exhibited a net nitrogen release, while twig litter followed a pattern of “enrichment—stabilization—release”. (4) After four years of decomposition, the estimated annual carbon retention of twig and leaf litter was similar (3.85 g?m-2?a-1 for twig litter and 3.72 g?m-2?a-1 for leaf litter). However, leaf litter retained significantly more nitrogen than twig litter (0.11 g?m-2?a-1 vs. 0.06 g?m-2?a-1). This study highlights the complementary roles of twig litter in promoting carbon accumulation in alpine shrubland due to its slower decomposition. In contrast, leaf litter plays a more crucial role in alleviating soil nitrogen limitation due to its faster nitrogen release and higher nitrogen return. Our results provide valuable foundation for accurately assessing the contributions of twig and leaf litter to soil carbon and nitrogen cycling.

Aims In order to explore the effect of root-derived volatile compounds from Chinese fir (Cunninghamia lanceolata) on the growth of neighboring plants under low phosphorus stress, a controlled indoor pot experiment was conducted. Methods One-year-old seedlings of the same clonal line of Chinese fir were selected as the study subjects. The experiment was designed with two phosphorus supply treatments: a sufficient phosphorus supply treatment (1.0 mmol/L KH2PO4) and a no phosphorus supply treatment (0 mmol/L KH2PO4). n-Decane, as an exogenous volatile organic compound, was applied to each pot at a concentration of 0.3 mL to simulate the release of volatile organic compounds from the roots of Chinese fir. The selection of n-decane was based on its significant expression under phosphorus-deficient conditions, as observed in previous studies. This allowed the assessment of the impact of root-exuded volatile organic compounds on various growth-related parameters of neighboring plants, including root morphology, physiological traits, and molecular-level changes. In particular, the root morphological and physiological parameters included root length, surface area, specific root length, specific surface area, as well as phosphorus content and phosphorus use efficiency Important findings Compared to the sufficient phosphorus supply treatment, the addition of n-decane under no phosphorus supply treatment significantly affected the root morphological growth of Chinese fir seedlings. In particular, root length was decreased by 37.4%, dry mass was reduced by 29.3%, and specific surface area was increased by 54.1%. Proteomic analysis of the roots revealed that under phosphorus deficiency, the addition of n-decane increased the expression of glycine synthase (Glutamate-glyoxylate aminotransferase) by 1.3-fold, while the expression of glycine dehydrogenase (Threonine aldolase) decreased significantly by 33.3%, leading to a accumulation of glycine. Glycine played a crucial role in the adjustment of root morphology. Regarding phosphorus utilization, compared to the adequate phosphorus treatment, n-decane addition under phosphorus-deficient conditions resulted in a significant decrease in root phosphorus content by 15.1%, but an increase in root phosphorus use efficiency by 19.0%. In conclusion, the addition of n-decane not only significantly enhances the phosphorus use efficiency in Chinese fir roots but also influences the regulation of root morphology by modulating glycine levels. This dual effect contributes to improving the adaptability of Chinese fir seedlings to phosphorus deficiency stress, potentially through mechanisms that optimize both phosphorus acquisition and root growth under phosphorus-deficient conditions. The results of this study offer new insights into the potential allelopathic mechanisms mediated by volatile organic compounds and their broader implications for forest management and plant community dynamics.

Aims In boreal forest ecosystems, forest fires and soil microorganisms, along with their interactions, play a crucial role in shaping the soil environment. The rhizosphere soil microbial community, being one of the most sensitive bioindicators to environmental changes, provides critical insights into the stability of soil ecosystems. Understanding the structural changes in both rhizosphere and bulk soil microbial communities is essential for a comprehensive assessment of soil environmental stability in boreal forests. Methods This study focused on the rhizosphere soil of Larix gmelinii, a dominant tree species in northern China's forests. Fungal and bacterial communities were analyzed using ITS and 16S rRNA high-throughput sequencing technologies to investigate the effects of forest fires on the dynamics of soil microbial communities. Important findings (1) Forest fires significantly reduced soil organic carbon content (decreased by 40.1% in rhizosphere soil and 15.7% in bulk soil), total nitrogen content (decreased by 51.3% in rhizosphere soil and 38.9% in bulk soil), as well as β -1,4-glucosidase activity (decreased by 83.4% in rhizosphere soil and 72.7% in bulk soil) and β -1,4-N-acetylglucosamine glucosidase activity (decreased by 54.6% in rhizosphere soil and 13.4% in bulk soil), while dissolved inorganic nitrogen content increased significantly after the fire (increased by 21.1% in rhizosphere soil and 431.6% in bulk soil). (2) After fire, the Shannon Wiener index of fungi in rhizosphere and bulk soils decreased significantly (decreased by 12.2% in rhizosphere soil and 13.7% in bulk soil), while the Shannon Wiener index of bacteria increased significantly (increased by 8.8% in rhizosphere soil and 10.2% in bulk soil). β-diversity analysis further revealed significant differences in fungal and bacterial community structures between rhizosphere and bulk soils. (3) Redundancy analysis shows that soil organic carbon, total nitrogen, dissolved organic carbon, dissolved inorganic nitrogen content, β -1,4-glucosidase activity, and β -1,4-N-acetylglucosamine activity are the main factors affecting the fungal and bacterial community structure in rhizosphere and bulk soils after fire. Structural equation modeling further elucidated the direct and indirect effects of forest fires on soil properties, enzyme activities, and microbial community structures. This study is helpful in understanding the changes of soil microbial community structure in the Great Xing’an forest area after fires, which is of great significance for post fire ecological restoration and the adoption of corresponding protection and management measures.