Oak is a general term for plants in the genus Quercus of the Fagaceae family, and the plants are widely distributed across the continents of Asia, Europe, North America, and Africa in the northern hemisphere. They are also among the important dominant species in broad-leaved forests from temperate to tropical regions in China, ranking first in both area and stock volume. Additionally, as important tree species with multiple uses such as timber, industrial applications, fruit production, and ecological functions, the systematic development and sustainable utilization of oak resources have become a key research spot in forestry, attracting increasing attention. However, in the practical production and application of oak trees in China, there exist problems such as limited systematic evaluation of important applied traits, a shortage of elite varieties, an underdeveloped breeding system, and non-standardized management practices for secondary forests. Since the 1930s, researchers have conducted a series of studies on oak diversity and evolution, germplasm resource collection and trait evaluation, new variety and cultivar breeding, seedling propagation, and forest cultivation and management, achieving significant research results. Based on a thorough comparison with the current status of oak research in overseas, this paper systematically reviews core progress in various aspects of domestic oak scientific research, discusses shortcomings and problems in current studies, and offers suggestions and prospects for future research directions in China, aiming to provide a reference for the development of oak resources and the industry of precious tree species in China.

Objective: In this study, a smart national park technology system was built with artificial intelligence (AI) as the core, through integrating space-air-ground monitoring data, AI algorithms, and ecological mechanism knowledge, to break through the technical bottlenecks of precise understanding of the dynamic processes of complex ecosystems in national parks, intelligent fusion of multi-source heterogeneous data, and precise simulation and deduction of management strategies. The system construction aims to realize the intelligent management of the entire process and cycle of monitoring, analysis, evaluation, decision-making in national parks, comprehensively improving the governance capacity and protection effectiveness of national parks. Method: Based on the demand for intelligent development of national parks, a smart national park system architecture with AI as the core was proposed, and a four layer system framework including infrastructure layer, data resource layer, business function layer, and application service layer was constructed. Design key technical modules included the space-air-ground integrated perception network, a big data intelligent fusion processing platform, an AI intelligent analysis center, and a digital twin decision-making platform. Focusing on five typical application scenarios of intelligent protection, intelligent monitoring, intelligent evaluation, intelligent management, and intelligent utilization, the implementation path and core technical support of AI based smart national parks were systematically elaborated. Result: This system utilized an integrated space-air-ground perception network to achieve comprehensive precision monitoring of ecological elements across the entire area. Based on a big data platform, it integrated and cleaned multi-source heterogeneous data. An AI analysis hub was used to deeply mine and predict ecological processes and change patterns. The digital twin platform was used to achieve the real-time 3D reproduction of the ecological situation and precise deduction of management strategies, which enhanced the data processing capability and intelligent decision-making efficiency of national parks, and provided scientific, precise, and intelligent decision-making solutions for intelligent management. Conclusion: The smart national park technology system can effectively address the inefficiency and insufficient intelligence of existing management models, and realize a comprehensive, multi-dimensional, long-term, and refined understanding and efficient management of national park ecosystems. It provides a technical pathway and practical example for addressing the theoretical challenges of understanding complex systems in nature reserves and adaptive management. It has important theoretical value and promotion significance for driving the transformation of the national park governance system towards being data-driven and intelligently decided, thereby strengthening the function of the national ecological security barrier.

Objective: This study aims to explore the dynamic changes in morphology and physicochemical indexes during the flowering process of tree peony with different flower types, so as to provide a theoretical basis for the regulation of flower types and cultivation management of tree peony in the future. Method: The flower buds (flowers) of 13 different developmental stages in the flowering process of the single-petal cultivar Paeonia ostii ‘Fengdan’ and the chrysanthemum cultivar P. suffruticosa ‘Lianhe’ were used as experimental materials. The dynamic changes in the external morphology and the relevant important physiological and biochemical indexes [indole acetic acid (IAA), gibberellin acid (GA₃), abscisic acid (ABA), zeatin riboside (ZR), soluble sugar, soluble protein, superoxide dismutase (SOD), peroxidase (POD)] were determined through observation and measurements. Result: The flower buds (flowers) of P. ostii ‘Fengdan’ and P. suffruticosa ‘Lianhe’ showed different degrees of growth in width and height from the overwintering bulb stage to the full blooming stage. Both of them began to grow rapidly at the big-bell stage and the small-bell stage, respectively, and reached their peak at the full blooming stage. From the initial flowering stage to the full blooming stage, the ZR content of P. ostii ‘Fengdan’ increased, while ZR content of P. suffruticosa ‘Lianhe’ continued to decrease. The change trends of soluble sugar and soluble protein contents of P. ostii ‘Fengdan’ and P. suffruticosa ‘Lianhe’ were consistent, but the content of soluble sugar and soluble protein of P. ostii ‘Fengdan’ was always higher than that of P. suffruticosa ‘Lianhe’ from the color-exposure stage. Both P. ostii ‘Fengdan’ and P. suffruticosa ‘Lianhe’ showed an increasing trend in SOD content during the blooming stage compared to the previous stage. As the developmental stage continued, the SOD content of P. ostii ‘Fengdan’ showed a tendency to first increase and then decrease, while P. suffruticosa ‘Lianhe’ showed a tendency to first decrease and then increase. The change trend of POD content in flower buds (flowers) of P. ostii ‘Fengdan’ and P. suffruticosa ‘Lianhe’ at different development stages was basically the same, but there were slight differences in the magnitude of variation. Conclusion: The rapid growth stage of P. ostii ‘Fengdan’ is from the big-bell stage to the full blooming stage, and the fastest growth stage of P. suffruticosa ‘Lianhe’ is from the small-bell stage to the full blooming stage. High levels of IAA and low levels of ABA and GA₃ can promote the flowering of P. ostii ‘Fengdan’ and P. suffruticosa ‘Lianhe’ flowers. High levels of ABA/IAA, ABA/GA₃ and low levels of ZR/IAA, ZR/GA₃ may be more conducive to breaking dormancy of tree peony buds. There may be greater fluctuations in various hormones during budding stage and the circular peach stage. The stage of highest content of nutrients and antioxidant enzymes in buds of P. ostii ‘Fengdan’ and P. suffruticosa ‘Lianhe’ is the stage of budding stage. The small-bell stage is the key stage for differentiation of different varieties of peonies towards different flower types.

Objective: Common wood conditioning methods, such as the saturated salt solution method and the saturation-drying method, have limitations such as long equilibrium time and poor control accuracy, which makes it challenging to meet the testing requirements of nuclear magnetic resonance (NMR) technology. A new conditioning method, the water-addition-equilibrium method, was proposed in the present paper to reduce the conditioning time and improve the control accuracy. Method: Poplar wood (Populus spp.) was conditioned to the target moisture contents of 5%, 15% and 25% using the new method. After adding water, the equilibrium conditions were set as follows: an equilibrium temperature of 45 ℃ with equilibrium times of 48 h, 72 h and 96 h; and equilibrium temperatures of 60 and 75 ℃ with times of 24, 48 and 72 h. Two critical parameters in the water-addition-equilibrium method, namely equilibrium temperature and equilibrium time, were optimized by analyzing the moisture content profile along the direction of water addition and transverse relaxation time spectra obtained from the low-field NMR tests. Result: The results demonstrate that at equilibrium temperatures of 45, 60 and 75 ℃, the equilibrium time has no obvious effect on the actual moisture content deviation and standard deviation of the samples. Under similar target moisture content conditions, the actual moisture content deviation of the samples obtained by the water-addition-equilibrium method is generally smaller than that obtained by the saturated salt solution method. For the target moisture contents of 5% and 15%, the samples’ internal moisture content gradient stabilized after conditioning at 45 ℃ for 72 h or 60 ℃ for 48 h; for the target moisture content of 25%, the critical parameters are conditioning at 45 ℃ for 72 h or 60 ℃ for 24 h. Additionally, secondary equilibrium processes conducted at room temperature can further minimize the moisture content gradient within the sample, bringing it closer to a quasi-equilibrium state. Notably, under the conditions of the equilibrium temperature of 75 ℃ and the equilibrium time of 24 h for the target moisture content of 15%, as well as the equilibrium temperature of 60 ℃ and the equilibrium time of 24 h for the target moisture content of 25%, the transverse relaxation time spectra of samples exhibited multiple peaks. In contrast, other equilibrium conditions yielded spectra with only a single bound water peak. The optimal parameters derived from the combined analysis of the internal moisture content gradient and NMR spectra suggest equilibrating at 45 ℃ for 72 h or 60 ℃ for 48 h. Conclusion: Compared to the traditional method, the proposed water-addition-equilibration method is more efficient and more accurate in terms of actual moisture contents. This method offers a new approach to regulating the moisture content during NMR characterization of wood.

Objective: Seasonal drought is a significant factor limiting tree growth, and high-intensity water use by trees can easily lead to soil dry layer formation. This study investigates the characteristics of soil water movement in Robinia pseudoacacia plantations in the loess region of western Shanxi under simulated drought conditions, aiming to provide theoretical support for optimized vegetation allocation in this area. Method: A 20-year-old R. pseudoacacia plantation in the western Loess Plateau was selected for an in-situ controlled experiment with three gradients: control (natural conditions), dry (50% precipitation reduction), and extremely dry (100% precipitation reduction). Soil water content (SWC) and soil water potential (SWP) were measured at 9:00 on the day after rainfall events and on typical sunny days using the oven-drying method and soil tensiometers, respectively. The zero flux plane (ZFP) method was applied to analyze soil water transport patterns under different drought gradients. Result: 1) In the control plot, torrential rain events increased the soil moisture content in the 0–60 cm layer, with the increase diminishing with soil depth. The post-rain moisture content in the 0–10 cm layer reached 32.42%±8.63%, rate of increase: 60.4%. Moderate and light rainfall only transiently affected shallow SWC, while deep soil layers (>60 cm) showed no response. Dry treatment exhibited limited SWC increases in shallow layers (only after torrential rainfall, peaking at 12.25% ± 3.51%), and extremely dry treatment showed no SWC changes. 2) After torrential rainfall, SWP in the shallow layer (15–30 cm) of the normal treatment significantly increased by 25 kPa, showing a strong positive correlation with rainfall (r = 0.781). Moderate and heavy rainfall had minimal effects. Dry treatment showed weaker SWP responses (r = 0.710), while extremely dry treatment exhibited no significant correlation. 3) The distribution of zero flux planes (ZFPs) varied with different drought treatments. In the normal plot, precipitation significantly influenced the ZFP position: after torrential rainfall, water transport in the normal treatment shifted from upward evaporation to downward infiltration, with ZFP descending to 60 cm. In dry treatment, water primarily migrated to deeper layers (45–60 cm). Extremely dry treatment maintained continuous evaporation in the surface layer (0–30 cm) and upward water movement in deep layers (80–100 cm), with stable ZFP positions. Under moderate and light rainfall, the overall direction of soil water movement across all gradients remained unchanged before and after the rainfall. Conclusion: Soil water dynamics in R. pseudoacacia plantations in the Loess Plateau of western Shanxi Province exhibit significant vertical stratification. The variability of SWC and SWP decreases with soil depth and drought intensity. Soil water transport direction is jointly influenced by depth and drought severity. Torrential rainfall drives shallow soil water recharge, but as drought intensifies and shallow water becomes insufficient, R. pseudoacacia roots absorb deeper soil water to meet transpiration demands. This study reveals the characteristics of soil water movement in R. pseudoacacia plantations under drought conditions, providing theoretical support for optimized vegetation allocation in the region.

Objective: This study aimed to investigate the effects of forest grassland grazing on surface fuel characteristics, potential surface fire behavior, soil physicochemical properties, and understory plant diversity in Larix gmelinii var. principis-rupprechtii and Pinus tabuliformis forests, and to propose a grazing-based sustainable fire risk management strategy that provides a scientific pathway for fire risk prevention in forest management areas. Method: This study focused on two typical coniferous forests in north China: mature stands (41?60 years old) of L. gmelinii var. principis-rupprechtii and P. tabuliformis. Sample plots were established under ungrazed and moderate grazing conditions (3 cattle·hm^?2), where surface fuel characteristics, soil physicochemical properties, and understory plant diversity were surveyed. Based on the 50th percentile (16 km?h^?1) and 97th percentile (27 km?h^?1) of wind speed during the fire season (2010—2023), simulations of surface fire spread rate, fireline intensity, and flame length were conducted using BehavePlus 6.0. One-way ANOVA was applied to evaluate the long-term impacts of grazing on soil physicochemical properties, and principal component analysis (PCA) was used to assess the comprehensive effects of grazing on surface fuel characteristics, potential surface fire behavior, and understory plant diversity, thereby exploring the feasibility of grazing as an ecological fuel management measure. Result: 1) Forest grassland grazing significantly reduced herb fuel load and surface fuelbed depth in both forest types by 72.09%?75.22% and 79.07%?89.74%, respectively, while enhancing herb layer species diversity, with the Shannon-Wiener index increasing by 12.42%?42.67% and the Simpson index by 11.11%?33.33%. Grazing decreased total soil phosphorus by 21.74% in L. gmelinii var. principis-rupprechtii forests and total soil potassium by 2.91% in P. tabuliformis forests; 2) Fire behavior simulations demonstrated that under extreme wind speeds (27 km?h^?1), grazing maintained fireline intensity below 500 kW?m^?1 and reduced flame length from 3?4 m to less than 1.5 m; 3) PCA results revealed that grazing treatments achieved the highest comprehensive scores for both forest types. In L. gmelinii var. principis-rupprechtii forests, grazing balanced wildfire risk reduction with ecological resilience, whereas in P. tabuliformis forests, combining grazing with the introduction of highly fire-resistant herbaceous species may better harmonize fire risk control with understory plant diversity conservation. Conclusion: Moderate intensity grazing can serve as a nature-based wildfire risk management solution, but attention should be paid to the risk of phosphorus and potassium depletion under long-term grazing, and grazing strategies should be tailored to species-specific ecological feedbacks.

Objective: This study aims to quantify the net carbon exchange of a temperate natural deciduous broad-leaved forest ecosystem, and investigate its responses to environmental factors at daily and seasonal scales, so as to provide a scientific basis for constructing carbon cycle prediction models and accurately estimating net ecosystem carbon exchange. Method: The typical natural deciduous broad-leaved forest ecosystem of Betula platyphylla–Populus davidiana in Labagoumen, Huairou District, Beijing was taken as the research object. The eddy-covariance technique was used to determine net ecosystem carbon exchange and relevant environmental factors in 2022. Wavelet analysis and other methods were adopted to explore the time lag and the main driving factors between net ecosystem carbon exchange and environmental factors at daily and seasonal scales. Result: 1) The cumulative annual gross ecosystem productivity, ecosystem respiration, and net ecosystem carbon exchange of B. platyphylla–P. davidiana natural forest ecosystem in Labagoumen, Beijing in 2022 were 1330, 930, and ?400 g·m^?2a^?1, respectively. 2) At the daily scale, the main influencing factor of ecosystem respiration was air temperature, with a delay time of 2.82 hours. The gross productivity and net carbon exchange of the ecosystem were mainly affected by photosynthetically active radiation and varied synchronously with photosynthetically active radiation. The results indicated that photosynthetically active radiation affected net ecosystem carbon exchange by primarily influencing gross ecosystem productivity. 3) At the seasonal scale, photosynthetically active radiation was the main influencing factor of net ecosystem carbon exchange with a time lag of 14.2 days. Although precipitation was the main factor affecting the change of ecosystem respiration and gross ecosystem productivity, the similar responses of ecosystem respiration and gross ecosystem productivity to precipitation resulted in a negligible correlation between net ecosystem carbon exchange and precipitation. Conclusion: The net carbon exchange in the B. platyphylla–P. davidiana natural forest ecosystem is more sensitive to photosynthetically active radiation at both daily and seasonal scales compared to air temperature, probably due to the susceptibility of remote mountains to cloud shading.

Objective: In order to elucidate the potential mechanism through which arbuscular mycorrhizal fungi (AMF) facilitated the invasion and spread of exotic plants, the feedback effect of AMF domesticated by both the exotic plant Robinia pseudoacacia and the native plant Platycladus orientalis on photosynthetic properties, root architecture, mycorrhizal characteristics and growth of the host plants and the interrelationships among these variables were investigated. Method: Rhizosphere soil collected from the mixed forest of R. pseudoacacia and P. orientalis and adjacent grassland in Wangdonggou watershed, Changwu county, Shaanxi Province, was served as AMF inoculum. A pot experiment was conducted to determine the effects of the different inoculum on leaf gas exchange parameters, root architecture, mycorrhizal characteristics and seedling growth of both species. Result: 1) Compared to non-AMF treatment, AMF inoculation significantly increased the root length of R. pseudoacacia and the biomass, net photosynthetic rate, root length, root surface area, and root volume of P. orientalis. Conversely, it decreased the net photosynthetic rate of R. pseudoacacia and the intercellular CO₂ concentration of P. orientalis. 2) Compared to grassland AMF treatment, mixed forest AMF significantly reduced the net photosynthetic rate of R. pseudoacacia and the biomass, root length, root surface area and root volume of P. orientalis. 3) The mycorrhizal colonization and soil hyphal density of both species inoculated with mixed forest AMF were significantly lower than those in grassland AMF treatment. 4) P. orientalis exhibited significantly higher dependency on grassland AMF than on mixed forest AMF, whereas R. pseudoacacia showed low dependency on AMF, with no significant difference between grassland AMF and mixed forest AMF treatments. 5) The biomass of AMF-inoculated P. orientalis was positively correlated with its root length, root surface area, root volume, root diameter, arbuscular colonization rate and soil hyphal density. Among these, root length, arbuscular colonization rate, and hyphal density had the highest explanatory power for the variation in biomass. Conclusion: Inoculated with mixed forest AMF significantly decreased root colonization rate and soil hyphal density of P. orientalis. This alteration, combined with the synergistic effect of mycorrhizal symbiosis on the root architecture, significantly suppressed its growth under pot conditions, weakened its competitive advantage and enhanced the competitive ability of R. pseudoacacia, thereby facilitating the invasion and spread of R. pseudoacacia.

Objective: According on the study of growth characteristics at seedling stage of 8 half-sib families of Malania oleifera from 7 germplasm resources at different altitudes in Yunnan Province, the combined selection of families and individual plants was conducted, providing a theoretical basis for precise grading of seedlings, formulating the seedling cultivation measures and long-term breeding strategies of M. oleifera. Method: A sowing and seedling experiment was conducted with freely pollinated seeds that were collected from 8 superior M. oleifera plants with good shape and stable fruit setting rate, at 7 different altitudes, to measure the growth, form quality, leaf traits of the half-sib family seedlings. The mathematical growth model optimization, membership function evaluation, cluster analysis, and analytic hierarchy process were used to evaluate growth characteristics at seedling stage of half-sib families of M. oleifera and complete the combined selection of families and individual plants. Result: During the measurement period, the growth of seedling height and ground diameter of 8 M. oleifera half-sib families derived from 7 different altitudes germplasm resources showed a“slow?fast?slow”growth rhythm. There was a significant difference in the net growth volume of seedling height and ground diameter among the half-sib families, with the minimum value of seedling height net growth volume of 0.98 cm, the maximum value of 13.07 cm, and the range of extreme difference of 12.09 cm, and the coefficient of variation ranged from 25.8% to 64.5%. The minimum value of ground diameter net growth volume was 0.33 mm, the maximum value was 1.87 mm, the extreme difference reached 1.54 mm, and the coefficient of variation ranged from 15.5% to 43.6%. There were differences in the beginning of rapid growth, the end of rapid growth and the rapid growth period among different families, thus the seedlings were able to be divided into three types of rapid growth seedlings during the early, middle and late stages, which accounted for 33.8%, 36.6% and 29.6% of the total seedlings, respectively. Among them, the seedlings of rapid growth at the ground diameter during the early, middle and late stages accounted for 81.7%, 12.7% and 4.2% of the total seedlings, respectively. Q-type clustering analysis clustered the seedlings into 3 classes at an euclidean distance of 7.97. Class I contains 21 individual plants with fast growth rate, average seedling height of 39.4 cm and average ground diameter of 6.86 mm; class Ⅱ contains 48 individual plants with moderate growth rate, average seedling height of 28.0 cm and average ground diameter of 6.36 mm; class Ⅲ contains 3 individual plants with slow growth rate, average seedling height of 15.9 cm and average ground diameter of 5.67 mm. In the hierarchical analysis, the cumulative total weight of seedling height, ground diameter, seedling index, crown width and leaf area was 0.756 0, which was the main preferred index for individual plants selection. Conclusion: The overall growth rhythm of half-sib family seedlings of M. oleifera from Yunnan Province shows allometric growth. According to the calculation of subordinative function value, the optimal mathematic model of growth is the Logistic model, the families F2, F7 and F12 are the best seedling height growth seedlings, families F23, F17 and F2 are the best ground diameter growth seedlings. According to the hierarchical analysis screening, F7-81-2, F7-81-3, F2-43-3, F16-133-3, F6-61-18, F2-43-3, F2-43-10 are the best individual plants.

Objective: In this study, the bifunctional nuclease gene family was identified, their protein-sequence characteristics and tissue-specific expression patterns were analyzed, and candidate molecular marker genes for the transition zone were screened, aiming to lay a foundation for clarifying the mechanism of heartwood formation in Chinese fir and provide a reference for transition-zone identification in other heartwood-forming species. Method: Bioinformatic methods were employed to identify the ClBFNs and to analyze the protein physicochemical properties, subcellular localization, sequence features and phylogeny. Expression pattern of ClBFNs in different tissues was analyzed and the candidate marker genes of transition zone were preliminarily screened. Annual rings from increment cores were taken, the RNA of each ring was extracted, and their RNA was analyzed by semi-quantitative RT-PCR (SqRT-PCR) and validated by qRT-PCR to refine the candidates. DAPI staining was used to observe nuclei of ray parenchyma cells in the wood-core transition zone and sapwood. Result: Four ClBFNs genes were identified, encoding proteins of 31.95 to 34.88 kDa. All proteins contained the S1-P1 nuclease domain and were acidic. Phylogenetically, ClBFN1 was clustered with PsBFN, PaBFN4, PtabBFN3, and PtaeBFN3 on the same evolutionary branch, whereas ClBFN2, ClBFN3, ClBFN4 were grouped with PtabBFN1 and PtaeBFN2. The semi- and quantitative PCR results showed that ClBFN2 was only expressed in the roots, while the other ClBFNs were expressed in the bark, roots, xylem, young needles, and mature needles. ClBFN1 exhibited high expression in roots and xylem but low expression in needles and bark. ClBFN3 was predominant in roots and needles, with lower expression in xylem and the lowest in the bark. ClBFN4 had lower expression in bark and xylem than in needles, with the highest level in mature needles. Only ClBFN1 showed a consistent expression pattern in the transition zone of the increment core. Radial section anatomy revealed that the length-to-width ratio of ray parenchyma nuclei decreased from the sapwood to the transition zone, and the nuclei of the ray parenchyma cells in the transition zone were shrunken and rounded, which are typical PCD hallmarks. Accordingly, ClBFN1 was designated as a molecular marker for the sapwood–heartwood transition zone in Chinese fir. Conclusion: Chinese fir possesses four BFN genes with conserved protein domains. During the heartwood formation, the family member ClBFN1 participates in PCD and responds specifically at the sapwood–heartwood transition zone, making it a molecular marker gene for the transition zone.

Objective: Michelia compressa is renowned for its exceptional ornamental value and stress tolerance, making it a superior parent for hybridization. This study observed the flowering characteristics of M. compressa and explored inter species and inter genus hybridization, in order to provide a theoretical guidance for the breeding of M. compressa through crossing with both closely related and distantly related species. Method: In this study, the flowering characteristics and dynamics of M. compressa, including stigma receptivity, microspore meiosis characteristics, and pollen germination were investigated. With M. compressa as a parent, hybridization experiments with both closely related species and distantly related species were conducted. The phenotypic characteristics of the resulting hybrid seedlings were measured, and the authenticity of the hybrid offspring was verified using SSR molecular marker technology. Result: M. compressa is a protandrous species characterized by a short temporal overlap between the female and male reproductive phases, without exhibiting secondary opening and closing. The meiosis of microspores occurs normally, and the pollen displays strong germination ability. Among the 16 hybrid combinations with M. compressa as a parent, M. compressa had high hybrid compatibility with M. maudiae, M. cavaleriei var. platypetala, M. maudiae var. rubicunda, and M. foveolata. There was unidirectional hybrid compatibility when crossing with M. wilsonii, whereas intergeneric reciprocal crosses with Yulania resulted in abortion. The hybridization of M. compressa and M. maudiae var. rubicunda expressed significant heterosis during the seedling stage, and SSR molecular markers confirmed a 100% authenticity rate for the hybrids. Conclusion: In summary, M. compressa exhibits a relatively high propensity for hybridization with closely related species, whereas hybridization with distantly related species presents greater challenges. This study lays a theoretical foundation for the hybridization breeding and germplasm innovation of M. compressa, and it is paving the way for the breeding of superior new varieties within the Michelia in the future.

Objective: In order to solve the problems of poor comprehensive soil fertility and low productivity of large-diameter poplar plantations in northern sandy areas, this study analyzed the response mechanism of poplar plantations to different water and fertilizer conditions through conventional fertilization and drip fertigation methods. This study aims to provide theoretical basis and technical guidance for developing reasonable measures to promote forest growth and sustainably maintaining soil fertility. Method: In this paper, 11–12-year-old Populus × euramericana cv. 74/76 plantation on northern sandy soil was studied using a split-plot experimental design. The irrigation form was the main factor with two levels, conventional irrigation (CI) and drip irrigation (DI). Different types of fertilizing were the sub-factors, with six levels of no fertilization (F₀M₀), controlled-release fertilizer (F_cM₀), water-soluble fertilizer (F_NPKM₀), organic manure (F₀M₁), controlled-release fertilizer and organic manure (FcM₁), water-soluble fertilizer and organic manure (F_NPKM₁), (a total of 12 treatments). After continuous treatments for 2 years, the changes in diameter at breast height (DBH), as well as the physicochemical properties and enzyme activity of the soil were measured. Result: Drip irrigation was more effective in promoting the DBH growth of poplar plantations than conventional irrigation under the same fertilization conditions. Different types of fertilizers and their combinations had varied effects on poplar DBH growth and soil fertility. Among them, under drip irrigation conditions, organic manure alone or combination of water-soluble fertilizer with organic manure had the best effect, while the controlled-release fertilizer in combination with organic manure had the worst effect. The application of organic manure was able to enhance soil alkaline phosphatase activity, increase soil available phosphorus content, maintain soil organic matter stability, promote breast height diameter growth, and effectively maintain soil fertility. Conclusion: In the poplar plantations on northern sandy soil, the application of organic manure or water-soluble fertilizer combined with organic manure has the best effect on promoting the DBH growth, improving soil nutrient availability, and maintaining soil fertility. Therefore, it is recommended to use organic manure as the base fertilizer and drip irrigation with water-soluble fertilizer as topdressing for water and fertilizer management of the poplar plantations in this area.

Objective: Through the selection and combination of composite microbial agents with significant synergistic and synergistic effects, the forest litter can be rapidly degraded, thereby significantly reducing combustibles such as dead branches and leaves under the forest, to enhance the fire prevention efficiency of the fireproof forest belt and further degrade litter into organic fertilizers. Method: A test plot was set up in the experimental forest farm of Jiangsu Academy of Forestry in the southern suburb of Nanjing. Based on a previous experimental result that there were the synergistic and synergistic effects of single strain, dual-strain combination, and composite microbial agents on litter degradation, the organic matter content and degradation rate were determined by burning at 550 ℃, and the maturation of the heap was evaluated by small rape seed germination index method. The temperature, moisture content, and pH value of different composite microbial agents on litter degradation of fermented piles were determined by setting up a tank experimental pile area and a forest experimental area, and the most suitable amount and time of composite microbial agents were selected to evaluate the degradation effect. Result: The order of temperature change in the litter degradation fermentation heap of fireproof landscape tree species was compound microbial agent Ⅰ> compound microbial agent Ⅱ> dual microbial agent Ⅲ> control CK. With the increase of treatment time, the water content and organic matter content of microbial agent Ⅰ treatment decreased the fastest, the pH value changed the most actively, and the organic matter degradation effect (P<0.05) was the most obvious, followed by other treatments. The results of 4 factors and 4 levels orthogonal test showed that microbial agent Ⅰ had a significant synergistic and synergistic effect on the degradation rates of litter. The degradation rates of litter by different compound microbial agent Ⅰ, Ⅱ, double microbial agent Ⅲ and CK treatment were 92.3%, 82.7%, 62.1% and 25.5%, respectively, and there were significant differences in the degradation rates of litter between the compound microbial agents and the control (P<0.05). On June 10, the degradation rate of understory litter reached 100% after 30 days of treatment with 30 kg·hm^?2 compound microorganisms I, which was both efficient and economical. After 30 days of treatment, GI of compound microbial agent Ⅰ,Ⅱ and double microbial agent Ⅲ was 98.2%, 92.3% and 89.7%, respectively, which all exceeded the harmless level of GI>80% maturation (P<0.05). Conclusion: The treatment of microbial agent I can rapidly degrade the litter of tree species in fire-resistant landscape and achieve the goal of reducing understory combustible materials.

Objective: To address the challenges of low identification accuracy and insufficient robustness in existing detection algorithms for alien forest pests, which stem from factors such as diverse target scales, complex habitats, and frequent occlusions, this paper proposes a detection method integrating multi-scale attention features, termed MAF-YOLO. The method aims to significantly enhance the detection accuracy and generalization capability for alien pests in complex natural environments by strengthening the model’s feature extraction capability for targets of varying scales, particularly small-scale ones, and optimize the bounding box regression strategy. Method: The proposed method was based on the YOLOv5s baseline architecture, and its core modifications included: 1) A coordinate attention (CA) mechanism was embedded into the neck network to enhance the capture of key target features and suppress background noise. 2) A small target detection head with 160×160 pixel was added to construct a multi-level detection structure, thereby improving detection sensitivity for minute objects. 3) The Focal-EIoU loss function was employed to replace the original CIoU loss, in order to mitigate the imbalance between positive/negative and easy/hard samples, and refine object localization accuracy. 4) A domain adaptation training strategy was introduced to improve the model's generalization across diverse scenarios by pre-training on a large-scale general-purpose dataset. Result: The proposed model was trained and evaluated on an image dataset comprising 15 categories of potential and existing invasive forest pests. The improved YOLOv5s model, MAF-YOLO, demonstrated an increase in precision and recall by 3.6% and 4.4%, respectively, compared to the original YOLOv5s. In comparison with the SSD, YOLOv7, and YOLOv8 models, the average precision of the improved model was higher by 2.2%, 1.1%, and 0.3%, respectively. Furthermore, with the integration of domain adaptation, the model’s precision reached 77.9%, representing a 2.1% improvement over the baseline model under the same strategy. Conclusion: This study achieves precise recognition of invasive alien forest pests, enhances the model's accuracy and robustness, and provides theoretical and technical support for effective monitoring of alien forest pest.

Objective: This study aims to understand important distribution sites, population dynamics, habitat use, and movement characteristics of Anser indicus (bar-headed geese) in the Yarlung Tsangpo River Basin, so as to provide a basis for formulating conservation strategies for both the bar-headed geese population and their habitats, as well as to develop monitoring and control measures for avian influenza. Method: Three comprehensive surveys of the bar-headed geese were conducted with the same survey methods and routes, and the survey area covered 16 districts or counties within the jurisdiction of Xigaze, Lhasa and Shannan. Nyemo and Rinbung counties, where there is almost devoid of bar-headed geese because of the terrain, were used as the dividing lines by which the survey area was divided into east and west. Investigators scanned the surrounding area with a telescope along the riverside, farmland and marshes, and other places where bar-headed geese inhabit, and recorded the numbers of bar-headed geese population and the survey time, habitat type and distance from investigators by dosimeter. The non-parametric Kruskal-Walli’s method was used to test the significance of the population size of bar-headed geese and the number of individuals in different habitat types. The detailed activity locations of bar-headed geese in the Yarlung Tsangpo River Basin were obtained by satellite tracking, and R software was used to calculate the activity areas and analyze whether there was significant difference in the home range size and their habitat use between daytime and nighttime. Result: 1） The wintering population of bar-headed geese remained relatively stable in 2014 and 2018, with 66 729 and 65 261 individuals, respectively, and the population increased to 90 987 individuals in 2022. Lhunzhub in Lhasa and Samzhubze in Xigaze were the two key regions with the largest wintering bar-headed goose populations of more than 20 000 individuals. 2） Although the maximum recorded population size of bar-headed geese was 9 265 individuals, the majority of population sizes was less than 300 individuals, with fewer populations exceeding 1 000. There were significant differences in sizes among different populations. 3） The utilization of different habitats by bar-headed geese varied across years, however, they consistently showed a strong preference for wintering in unplowed barley fields, along with a high reliance on marshes, followed by farmland and natural waters. At the same time, satellite tracking results also showed that bar-headed geese mainly occurred in farmland and grassland during the daytime, and preferred to roost overnight on a shallow beach in a nearby river or reservoir. There was no significant difference in the home range size between daytime and nighttime. 4） The activities of bar-headed geese in the eastern and western of the Yarlung Tsangpo River Basin were relatively independent, yet an indirect connection existed via the Nyangqu River located in Gyantse county. Conclusion: In the recent year, the increase of bar-headed geese populations may be associated with the expansion of suitable habitats, especially the increase of farmlands, which have the barley left in the fields after the winter harvest, and the growing winter wheat crops that provide additional food sources for the wintering geese. In addition, this study has also showed that the communication between the wintering bar-headed geese in the east and west of Yarlung Tsangpo River basin is limited, however, considering that geese frequently move between Lhasa and Shannan, and between various regions of Xigaze, it is recommended that the relevant local departments set up a multi-sectoral and multi-regional joint prevention and emergency control mechanism to carry out the monitoring, prevention, and control of avian influenza in an efficient and scientific manner in the Yarlung Tsangpo River Basin of Xizang.

Objective: A handheld portable blueberry harvester is proposed for mountainous cultivation and small-scale scattered farmers, through rigid-flex coupling dynamics simulation and field picking tests to analyze working performance under different conditions, solving problems of low efficiency, high labor intensity, and high fruit damage rate in manual blueberry picking, providing theoretical reference for structural design of blueberry mechanical harvesting devices. 【Method】By analyzing the entire structure and working principle of the picking machine, the kinematics and dynamics model of the system was obtained. According to the technical requirements of the blueberry picking operation, Hypermesh and Ansys software were used to convert the key components of the harvester and the three-dimensional model of the blueberry plant into a flexible body. The rigid-flexible coupling mechanics simulation model of the picking device and the blueberry plant was established in Adams, and the distribution position of the blueberry fruits on the plant was marked in the simulation environment. The effects of coefficients of travel speed variation, hand drill’s rotation speed and clamping position on the dynamic performance of the system and the fruit picking force at different positions were analyzed through the blueberry picking simulation test. Using the simulation factors as independent variables, the self-developed portable picking machine was used to conduct single-factor field picking tests. Picking efficiency, ripe fruit picking rate, raw fruit shedding rate, and fruit breakage rate were used as evaluation indices to analyze the machine's harvesting performance and determine the optimal combination of the machine’s working parameters. Result: 1) Kinetic simulation results show that the picking mechanism tends to jam when the travel speed ratio coefficient K of the transmission device is too low. When the travel speed ratio coefficient K is too high, the mechanism moves violently, causing severe wear on the articulated parts. When the travel speed ratio coefficient K is too high, the mechanism moves violently, causing severe wear on the articulated parts. When K=1.3, n=180 r·min^?1, the maximum peak torque$ {M_{\Sigma O}}(t) $=3.0 N·m, which is smaller than the rated torque of 4.0 N·m of the drill, and meets the requirements for use. 2) Finite element analysis results indicate that the maximum positive stress of the key components of the transmission device is 196 MPa, which is below the material yield limit of 355 MPa, meeting the conditions for using. 3) The results of the rigid-flexible coupling simulation, the pre-picking test and the test of machine working parameters together show that: the best clamping position of the clamp is 1/3 to 2/3 from trunk to root of the plant, the best coefficient of travel speed variation of the machine is K=1.3, and the best rotation speed of the hand drill is n=180 r·min^?1. 4) Under the optimal combination of working parameters, the picking efficiency of the machine is 0.29 kg·min^?1, the picking rate of the mature fruit is 91.4%, and the shedding rate of the unripe fruit is 5.9%, the rate of fruit damage is 4.8%, and the machine picking efficiency is 5.08 times of the manual picking efficiency. Conclusion: The portable blueberry harvester developed meets the requirements of blueberry picking operations and is suitable for picking semi- highbush blueberry plants, and the results of the research can provide technical references and theoretical support for the design of small berry harvester.

Objective: Aiming at the issue of low traction performance of track shoes on tracked vehicles operating in soft forest soil conditions, this study combines the highly adaptive morphology of the goat hoof bulb with the grouser design of track shoes. A bionic goat hoof track shoe is designed, offering a new approach and solution for enhancing the traction performance of tracked vehicles in forest terrain. Method: Based on the prototype goat hoof, reverse engineering technology was used to construct a 3D model and extract the ridge curve of the hoof bulb contour. MATLAB software performed third-order curve fitting on this ridge curve to obtain its equation. This equation guided the design of the bionic grouser, leading to the development of the bionic goat hoof track shoe. Conventional straight grouser track shoes served as the experimental control. Based on Rankine’s passive earth pressure theory, theoretical calculation formulas for the traction force of both straight grouser and bionic goat hoof track shoes were derived. Soil mechanical tests, based on the soil conditions of Camellia oleifera forests in central-south China, were conducted to obtain characteristic soil parameters. These parameters were used in theoretical calculations to determine the theoretical traction force values for both shoe types. Using EDEM software, a discrete element system with soil parameters determined from forest soil was established. The Hertz-Mindlin model combined with JKR and HMB bonding models served as the contact model between soil particles. Simulations analyzed the traction performance of both track shoe types. Physical track shoes were manufactured, and soil bin tests were performed to obtain experimental traction force values. Result: Theoretical analysis showed that the theoretical traction force of the bionic goat hoof track shoe was 165.04 N, compared to 152.36 N for the straight grouser shoe, representing an increase of 8.32%. Analysis using EDEM’s post-processing functions revealed that the average simulated traction force for the bionic shoe was 181.17 N versus 161.33 N for the straight grouser shoe, an increase of 12.30%. Microscopic analysis of the soil particle field indicated that a higher proportion of particles around the bionic shoe exhibited high stress, leading to greater traction force. Soil bin tests demonstrated that the average experimental traction force of the bionic goat hoof track shoe was 173.41 N, compared to 150.89 N for the straight grouser shoe, an increase of 14.92%. These experimental results further validated the correctness of the theoretical calculations and simulation outcomes. Conclusion: Under soft forest soil conditions, the bionic goat hoof track shoe demonstrated superior traction performance compared to conventional straight grouser shoes across theoretical analysis, simulation analysis, and experimental testing. This conclusively proves the superiority of the bionic grouser design. The study provides a theoretical basis for the structural parameter design of track shoes aimed at enhancing the traction performance of tracked vehicles operating in forest terrain.

Objective: In this study, a roller-type leaf-stripping and bark-peeling machine was designed and developed to achieve continuous leaf-stripping and bark-peeling operations for annual Eucommia ulmoides twigs during harvest, in order to address the low mechanization level in the large-scale harvesting process of E. ulmoides leaf-used forests. Method: Based on the determined characteristic parameters of the material and the performance criteria of the machine, EDEM software was employed for simulation analyses and bench tests to determine the optimal configuration of parameters, including the pitch, spacing, and speed ratio of the dual-roller cutting mechanism. Besides, the most appropriate number of rollers and a reasonable transmission mode were determined to ensure that the machine’s design meeting both performance specifications and operational efficiency standards. The force situation of the hammer blade used for defoliation was analyzed to determine the structural dimensions and arrangement of the hammer blade mechanism, and the design of key components of the equipment was completed. The feed roller speed and hammer blade roller speed for defoliation and peeling were selected as experimental factors, and the defoliation rate, peeling rate, and production efficiency were used as experimental indicators, to evaluate the overall performance of the machine. Result: 1) The cutting efficiency of the dual-roller mechanism on E. ulmoides bark decreased as the roller spacing increased, but was not significantly correlated with either the pitch or the speed ratio. The optimal parameter set comprised the cutting roller diameter of 150 mm, length of 1250 mm, pitch of 2.5 mm, the dual-roller spacing of 10 mm, the speed ratio of 1, two pairs of dual-rollers, and the rotational speed of 400 r·min^–1. 2) The hammer blade mechanism was configured in a fixed-distance, even number, and uniformly spaced arrangement. When hammer blades were 130 mm in length, 50 mm in width, and 4 mm in thickness, with a spacing of 15 mm between each hammer blade, a total of 40 hammers, two pairs of dual-rollers, rotating at a speed of 1 200 r·min^–1, the optimal defoliation effect could be achieved. 3) Field trial results indicated that the machine based on the design parameters exhibited the highest stripping efficiency for E. ulmoides twigs harvested in the first day of the annual growth cycle, with a moisture content ranging from 58%?70%. The defoliation rate achieved 100%, peeling rate achieved 78%, and the production efficiency reached 64%. Conclusion: The roller-type leaf-stripping and bark-peeling machine has achieved all the main design objectives, and this design may provide a reference solution for the development of mechanized harvesting equipment for E. ulmoides leaf-used forests.

Objective: To clarify the mechanism of the new round of confirming collective forestland property rights on farmers’ forestry production input, and to provide theoretical basis for deepening the reform of collective forestland tenure. Method: On the basis of a unbalanced panel data of 3 158 sample farmers from 18 counties (cities) in 9 provinces (autonomous regions) from 2003 to 2021 and fixed effects models, by identifying the difference of incentive between the existing forestland before the new round of collective forestland tenure reform and the newly acquired forestland after the new round of collective forestland tenure reform and fully considering the social and economic environment changes around the collective forestland tenure reform, the impact of confirming collective forestland property rights on farmers’ forestry production input was estimated, and dynamic impact analysis and heterogeneity analysis were carried out. Result: 1) Confirming collective forestland property rights has a positive incentive effect on farmers’ forestry production input, and the positive cumulative effect of property rights is mainly reflected in forestry investment. 2) Farmers’ forestry production input on existing forestland has an obvious “Ashenfelter’s dip”, and awareness of avoiding property rights risks in capital input is stronger than in labor input. 3) The impact of the confirming collective forestland property rights on farmers’ forestry production input has significant regional and scale heterogeneity. Conclusion: Long-term stable property rights of forestland can effectively motivate farmers to increase forestry production input. It is necessary to continue to strengthen the property rights registration of collective forestland and make up for omissions and correct errors, implement the renewal of forestland contract rights according to local conditions, promote coordinate of high-level protection and high-quality development, and promote the appropriate scale management of collective forestland through mechanism and model innovation.

Objective: Forest tourism is an important means to guide the growth of characteristic industries in key state-owned forest areas, taking into account the dual goals of environmental protection and economic growth. Analyze the dynamic game process, equilibrium state, optimal strategy selection and development mode of stakeholders; explore the cooperation mechanism to promote the development of forest tourism, and provide theoretical support for the overall protection of key state-owned forest areas and the development of characteristic industries that can carry resources and environment. Method: The present study employs evolutionary game theory and numerical simulation to analyze the strategic choices and sensitivity changes of local governments, cultural tourism enterprises, and forest industry groups. Furthermore, it explores a cooperative mechanism aimed at fostering common development among these three entities. Result: 1) The achievement of equilibrium in the development of forest tourism is intricately connected to external funding support, dynamic subsidies, compensation fees for forest resources, and the costs and benefits of the three primary stakeholders. 2) The dynamic subsidies provided by local governments play a crucial role in promoting active collaboration among the three parties and safeguarding development. The amount of subsidy should be carefully adjusted to avoid reducing its incentive effect and increasing the fiscal burden on local authorities. Due to their profit-oriented nature, tourism enterprises are especially responsive to changes in costs, benefits, and fees for using forest resources. Additionally, differences in costs have a significant impact on the strategic decisions made by forestry groups. 3) Establish an externally driven mechanism, financially supported by the central government and guided by social capital, to achieve comprehensive management and alleviate pressure on existing entities. Complement this with an internally coordinated mechanism that includes a fair forest resource compensation system and a dynamic award and subsidy system for local governments, aiming to enhance cooperation fairness, positivity, and promote sustainable development of forest tourism. Conclusion: 1) As policymakers for forest tourism development, local governments prioritize the overall benefits of industrial development; tourism enterprises, as market entities, exhibit high sensitivity to their own costs and benefits; and forestry groups, as operators of forest resources, prioritize long-term resource protection and sustainable development. 2) To promote the development of forest tourism to achieve the advantage synergy mode, it is necessary to ensure that local governments are in a state of abundant funds, cultural tourism enterprises are in a state of optimized cooperation gain, and forest industry groups are in a state of net income gain of service optimization. 3) The establishment of an integrated collaborative mechanism, which combines external drive and internal coordination, can effectively mitigate conflicts of interest among stakeholders in forest tourism development and ultimately foster cooperation among them.

Objective: This paper constructs a triadic analytical framework of “forest reform-institution-rural households” to explore the mutual influence among the effectiveness of new round of collective forest tenure reform (hereinafter referred to as the effectiveness of the new forest reform), the functional efficiency of township forestry stations (hereinafter referred to as forestry station efficiency), and rural households’ income growth to provide a new perspective and empirical evidence for the reform and development of collective forest tenure, thereby offering policy insights for deepening the reform. Method: This paper adopts Chinese provincial panel data to construct a relevant indicator system. It utilizes the entropy weight method and the super-efficiency model (SBM) to quantitatively evaluate the effectiveness of the new forest reform and forestry station efficiency. Subsequently, a panel vector autoregression (PVAR) model is established to investigate the mutual influence among the effectiveness of the new forest reform, forestry station efficiency, and rural households’ income growth. Result: 1) The effectiveness of the new forest reform, forestry station efficiency, and rural households’ income growth exhibit diversified characteristics across different regions, with a certain positive propelling effect among them. 2) The effectiveness of the new forest reform and rural households’ income growth demonstrate self-reinforcing effects, whereas forestry station efficiency, constrained by its own resource allocation conditions, exhibits a short-term self-inhibiting effect. 3) When impacted by their respective shocks, the effectiveness of the new forest reform and rural households’ income growth can both reach positive maximum peaks in the current period and sustain for 3-4 periods. In contrast, forestry station efficiency exhibits a negative response in the first period, which then turns positive and gradually declines towards stability. Conclusion: There is a mutual promotion and restriction relationship among the effectiveness of the new forest reform, forestry station efficiency, and rural households’ income growth. This paper argues that, based on the construction of a ternary collaborative mechanism, the self-reinforcing effect of the effectiveness of the new forest reform should be fully utilized to strengthen policy coordination and continuously advance collective forest tenure reform. Resources at forestry stations should be allocated reasonably, and construction investment should be increased to ensure that the effectiveness of the reform is translated into rural households’ income. Additionally, targeted policies need to be formulated to broaden rural households’ income sources, thereby achieving rural sustainable development and improving household living standards.