Against the backdrop of global climate change and intensified human activities, grassland soil wind erosion has emerged as a prominent issue threatening ecological security, yet the synergistic driving mechanisms involving multiple factors remain unclear. To systematically reveal the independent and interactive effects of grazing and natural factors on erosion, this study employed a global meta-analysis approach, integrating observational and experimental data from 118 studies to quantitatively assess the effects of grazing, wind speed, precipitation, temperature, and interface layer characteristics. The main results are as follows: (1) Grazing alone significantly increased wind erosion by 14%, and enhanced wind speed was the primary climatic driver, increasing erosion by 13% independently; (2) A strong synergistic effect was observed between grazing and increased wind speed, with their combined impact amplifying erosion by 29%-106%, whereas grazing exhibited an antagonistic interaction with increased precipitation and an additive effect with warming; (3) Degradation of the interface layer (vegetation and soil surface) directly increased wind erosion by 17%-21% and further amplified erosion risk when interacting synergistically with grazing and wind speed, highlighting its core regulatory role. This study is the first to clarify, on a global scale, the key mechanisms by which multiple factors synergistically exacerbate wind erosion and to elucidate the pivotal function of the interface layer in multifactorial interactions, thereby providing a critical scientific basis for developing precise grassland wind erosion prevention and control strategies based on ecological thresholds and adapted to multi-factor interactions.

Under long-term greenhouse vegetable production, intensive nutrient inputs enhance crop yields but also lead to the accumulation of antibiotics and heavy metals in greenhouse soils, posing potential risks to crop productivity and soil health. However, studies examining the trade-offs between nutrient inputs and soil contamination remain limited in terms of quantitative assessment of contamination risks. In this study, greenhouse soils with different cultivation histories (<1 year, 5 years, and >10 years) were investigated. The risk quotient (RQ) and a multi-factor heavy metal pollution index (Pt) were used to quantitatively assess the potential risks of soil antibiotics and heavy metals (HMs) contamination to crop growth and soil health, identify key drivers of risks accumulation, and predict contamination risks under different nutrient levels through scenario analyses. The results showed that RQ exhibited “pseudo-persistence” during long-term cultivation and tended to accumulate in lower soil layers, whereas Pt increased continuously with cultivation duration and was predominantly retained in the plow pan layer. Soil nutrients were identified as the key drivers of antibiotic contamination risk, while soil texture played a dominant role in explaining heavy metal contamination risk. Scenario predictions indicated that further increases in nutrient inputs would substantially intensify soil contamination risks; notably, a 10 % increase in soil nutrient levels could elevate antibiotic contamination risk by more than 50 %. This study provides scientific evidence for the coordinated management of nutrient inputs and contamination risks in greenhouse agricultural systems.

In arid and semi-arid regions, oases function as critical socio-ecological systems. East Asia, particularly China and Mongolia, contains some of the world’s most densely concentrated oasis ecosystems. Since the early 21st century, oases in this area have expanded substantially with widespread vegetation greening. However, it remains unclear whether this notable expansion and greening reflect genuine improvements in ecosystem resilience or mask emerging vulnerabilities under limited water availability. Here, we quantified greening status and resilience dynamics of oases in East Asia from 2000 to 2020 using remote sensing time series. We developed a joint-threshold assessment framework to evaluate current stability state of vegetation in East Asian oases under water-constrained conditions. Results indicate that while East Asian oases exhibit overall expansion and greening trends, these improvements have not concurrently translated into enhanced regional ecosystem stability. Moreover, according to this framework, only 17% of all oases are classified as ‘sustainable’ in East Asia under current water-availability conditions, and a majority of the recently expanded oases are biased toward transitional states, indicating that these oases may be fragile under future water constraints. Overall, our study provides an operational diagnostic basis for prioritizing water-allocation strategies in the sustainable management of oases in arid and semiarid areas, as the apparent surface greening and vegetation expansion may coincide with accumulating hydrological unsustainability and elevated degradation risk.

Wind erosion in grasslands is jointly regulated by grazing and climate change; however, the multi-factor interactions and their effects on land surface feedback mechanisms remain poorly understood. This study aims to elucidate the interactive effects of grazing and climatic factors on wind erosion in grasslands. Based on data from 68 global studies, we employed weighted response ratios and interaction effect models to quantify the individual and interactive effects of grazing and climatic factors (warming, precipitation, and wind speed) on wind erosion, vegetation, and soil characteristics. The results showed that: (1) Increasing grazing intensity significantly aggravated wind erosion (+13%) and reduced vegetation (-28%) and soil characteristics (-22%). Higher wind speed and warming significantly promoted erosion (+12%), whereas increased precipitation suppressed erosion (-5%) and facilitated vegetation recovery (+13%). (2) The combined effects of multiple factors exceeded the sum of their individual effects: the combination of grazing and climatic factors increased wind erosion by 37%, with synergistic interactions observed for increasing grazing intensity×wind speed increased (+32%), grazing×warming (+7%), and warming × wind speed (+36%). (3) Interaction types exhibited a consistent pattern: destructive factor combinations (grazing×wind speed/warming, warming×wind speed) were predominantly synergistic, whereas combinations of destructive and restorative factors (grazing×precipitation, precipitation×wind speed) were predominantly antagonistic. (4) Vegetation and soil properties served as critical mediators; however, a risk of decoupling the negative vegetation–wind erosion feedback exists under multi-factor stress. This study reveals that multi-factor interactions substantially amplify wind erosion risk, and that grazing regulation represents a core mitigation pathway. These findings provide a quantitative, multi-factor interaction-based reference for adaptive management of dryland grassland ecosystems, highlighting the need for future management to shift toward systematic strategies addressing multi-factor interaction risks.

Farmland shelterbelts serve as ecological barriers in desert oasis regions, mitigating harsh environmental conditions and supporting agricultural production. However, their edge effects should not be overlooked. Current research lacks comprehensive analyses of water, nutrient, and light competition across the spatiotemporal scales of shelterbelt networks, and existing light-distribution models often rely on simplified canopy representations that fail to capture within-crown heterogeneity. We conducted a three-year field study in an agroforestry system comprising Populus popular’s, Populus nigra, and maize to disentangle the spatiotemporal effects of water, nutrient, and light competition on maize yield, integrating three-dimensional shelterbelt reconstruction and radiation transmission simulations using the LargE-Scale Remote Sensing Data and Image Simulation Framework (LESS) model. Maize yield decreased by 33.82

Oases are the highlights of arid and semi-arid ecosystems, supporting local livelihoods and regional development. Despite the extensive coverage of arid and semi-arid lands in East Asia, the spatiotemporal dynamics of oases in this region remain poorly understood, particularly under varying socioeconomic and policy conditions. In this study, we used Landsat imagery on the Google Earth Engine platform to generate 30-m resolution maps of oasis distribution in East Asia from 2000 to 2020, by employing the LandTrendr-PCA (principal component analysis) collaborative monitoring framework and various machine learning techniques. We systematically analyzed oasis evolution and identified the main influential factors by using a Random Forest model. Our results reveal that oases in East Asia, predominantly located in northwestern China and the eastern and western sides of southern Mongolia, expanded by 5.3 million hectares (Mha), or 12.8% from 2000 to 2020, equating to an average annual growth of 0.3 Mha, and over 90% of this expansion occurred in China. However, the study also revealed that approximately 9.5 Mha of oasis areas degraded into desert during the same period, about 67% of which occurred in Mongolia. Furthermore, our analysis highlights divergent influential factors of oasis dynamics in China and Mongolia, which went through different paths of socioeconomic development, especially in terms of water resource availability and climate change. In China, water resource availability was the primary factor that drove oasis dynamics, whereas in Mongolia climate change played a more prominent role. This study establishes a robust framework for long-term oasis monitoring, addresses critical gaps in oasis mapping, and offers valuable insights for sustainable oasis management in arid and semi-arid regions. Plain language summary: In the water-scarce regions of East Asia, oases are vital ecosystems that sustain agriculture and local livelihoods. Their dynamics and distribution, influenced by complex natural and social interactions, remain poorly understood. We generated distribution maps of East Asian oases from 2000 to 2020, thereby addressing this knowledge gap by examining their spatiotemporal evolution and identifying the main natural and socioeconomic factors that may affect these changes. Our findings show that oases in East Asia has expanded by 5.3 million hectares (Mha) or 12.8%, and over 90% of the oasis expansion occurred in northwest China. In the meantime, approximately 9.5 Mha of the oases in East Asia were transformed into deserts, and Mongolia accounted for about 67% of such land degradation. In China, the expansion of oases was largely related to water resources, whereas in Mongolia, climate change had a more pronounced impact. This research provides new insights to our understanding of oasis dynamics and supports sustainable management efforts in water-scarce environments.

Vegetation mitigates aeolian erosion primarily by modifying near-surface wind fields, but the plant-flow interactions underlying this effect remain insufficiently quantified. Most existing models represent vegetation as static roughness elements and therefore overlook the combined effects of plant architecture, dynamic motion, and aerodynamic reconfiguration. Here, we investigated three dominant desert shrub species (Nitraria tangutorum, Ammopiptanthus mongolicus, and Haloxylon ammodendron) by combining wind-tunnel experiments with high-speed photogrammetry. We developed a static-dynamic-aerodynamic framework to quantify plant-sway dynamics in real time and assess their direct effects on airflow. Our results reveal two distinct biomechanical paradigms. In A. mongolicus, high-frequency canopy motion increases local turbulence intensity, resulting in localized momentum loss and an 89% reduction in downwind shear stress, thereby weakening a key driver of sediment transport. In contrast, H. Ammodendron exhibits aerodynamic reconfiguration and flow stabilization, promoting morphological streamlining under high-velocity winds, reducing drag, and suppressing turbulence while maintaining an effective protection distance. As wind speed increases from 6 to 14 m s_ 1, its protection distance decreases by less than 9.5%. These findings establish a mechanistic link between shrub biomechanics and aeolian erosion potential, providing a quantitative basis for predicting the effects of vegetation on sediment flux and optimizing windbreak design for soil conservation

Forest degradation is widely assumed to drive a monotonic decline in belowground functioning, yet plant-soil feedbacks may transiently buffer stress. We tested this idea by quantifying the rhizosphere effect (RE), the percentage difference between rhizosphere and bulk soil, for soil carbon (C), nitrogen (N) and phosphorus (P) pools, enzymatic activities, and microbial biomass across four degradation stages in three types of shelterbelt forests. We found that REs generally increased or remained stable from undegraded to mild-moderate degradation stage and then declined sharply at severe degradation stage. This nonlinear pattern was consistent across species but differed in amplitude and timing, with Populus thevestina showing the largest early increases, Populus alba maintaining RE longer before decline, and Populus popularis reaching negative REs for SOC and microbial biomass phosphorus at the severe degradation stage. Early positive RE coincided with lower pH and higher water-soluble organic carbon (WSOC), soil water content (SWC), and enriched available N (NH4+ and NO3−) in rhizospheres, conditions that stimulate microbial activities and nutrient turnover. As degradation intensified, the significant differences between rhizosphere and bulk soil properties contracted and eventually disappeared, reflecting a decline of plant-soil feedbacks likely driven by reduced root exudation. Random-forest and redundancy analyses highlighted rhizosphere P, rhizosphere N, bulk soil WSOC, rhizosphere SWC, and bulk-soil stoichiometry as the most influential factors of these shifts, consistent with a transition from compensatory stimulation to functional collapse beyond a critical tipping zone. This study provides the first field evidence that rhizosphere functioning responds nonlinearly to forest degradation. Recognizing this transient compensatory phase advances our understanding of ecosystem belowground resilience and can inform the intervention windows for dryland forest restoration.

Large-scale reclamation of nabkha dunes into cropland is widespread in arid regions, yet the long-term trajectory and drivers of soil quality changes throughout deep soil profiles remain poorly understood. This study examined the vertical distribution (0-3 m) of soil quality across a chronosequence of croplands (2-5, 12-15, 25-30, and 40-50 years post-reclamation), along with bare and nabkha dunes in a desert-oasis ecotone of northwestern China. Based on soil samples collected from 100 locations using a grid-based method, a minimum data set-based soil quality index (SQI) was established. The results showed that SQI can be effectively determined using soil total porosity, silt content, soil organic carbon stock, clay content, and pH. The SQI was lowest in bare sand dunes across the entire profile, followed by nabkha dunes at 0-2 m depths (0.56-0.75). The conversion to cropland significantly (P < 0.05) enhanced the SQI, with increases ranging from 11.5 % to 126.6 % over time. This improvement was most pronounced at the 0-1 m depths, while more modest gains were also detected at deeper soil depths (1-3 m) of older croplands (25-30 and 40-50 years). Notably, pH at 0.4-3 m depths was 1.1-3.0 % higher in fields cultivated for 40-50 years than in those with 25-30 years, indicating a potential salinization risk. Spatial analysis revealed higher SQI values near water bodies, while the southeastern and mid-western nabkha dunes and bare sand dunes exhibited the lowest values. Cultivation duration was the dominant driver of SQI variation throughout the soil profile, followed by land use type, with both effects attenuating with depth. These findings demonstrate that long-term cultivation effectively enhances soil quality at 0-1 m depths in reclaimed desert soils while highlighting salinization risks in deeper layers (0.4-3 m), thereby providing a scientific basis for sustainable land management in arid agro-ecosystems.

In desert oasis regions, agroforestry systems play a crucial role in maintaining stable and high crop yields; however, they often face the “edge effect” caused by resource competition between shelterbelts and crops, resulting in yield reduction near forest edges. Despite extensive studies, quantifying the spatial extent and magnitude of shelterbelt-induced suppression at large scales remains challenging, and the key influencing factors and underlying processes are still unclear. In this study, we investigated 90 agroforestry plots (each composed of Populus alba var.pyramidalis and maize) at the Ulan Buh Desert Experimental Farm in China. By integrating airborne LiDAR and Sentinel-2 high-resolution remote sensing data, calibrated with in situ measurements, we examined the effects of shelterbelts on maize yield variation. Based on a leaf area index–yield model, we employed a generalized additive model (GAM) to derive the relative yield–distance curves under gradients of shelterbelt orientation, density, canopy density, and individual stand volume. Furthermore, a random forest model was applied to identify key shelterbelt characteristics influencing variations in maize absorbed photosynthetically active radiation, leaf chlorophyll content, canopy water content, canopy cover and gap fraction within 3H of the shelterbelt. Using a partial least squares path model (PLS-PM), we established the causal chain underlying the formation of shelterbelt-induced suppression effects. Finally, we proposed targeted strategies to mitigate these edge effects and enhance yield gains, providing both theoretical insights and practical guidance for optimizing agroforestry system configurations and maximizing productivity in desert oasis ecosystems.

Abstract Dust and dust storms are known to negatively affect human health, safety, and welfare. Most dust‐related studies have previously focused on the physical processes of dust initiation, transport, and deposition at various temporal and spatial scales. In recent years, more scholars have attempted to link the physical processes of dust to human health, safety, and welfare. The idea for this special collection, named “Dust and dust storms, from physical processes to human health, safety, and welfare” was proposed by members of the Dust Alliance for North America (DANA), a partnership of scientists and practitioners with the purpose of accelerating the transition of dust‐related research into service. Papers in this special issue covered a wide range of topics, including the physical processes of dust particles and dust events, and their subsequent impacts on human health, transportation safety, and welfare, with various temporal and spatial scales. These papers were jointly published in three American Geophysical Union (AGU) journals, namely, GeoHealth, Earth's Future, and Journal of Geophysical Research (JGR)‐Atmospheres. The special collection opened in May 2023 and closed in June 2025. Eventually, a total of 24 papers were published as part of this collection, including five papers in GeoHealth, two in Earth's Future, and 17 in the JGR‐Atmospheres. Collectively, these papers report the latest interdisciplinary efforts by the research community to understand the physical processes of dust and its societal effects.

Shelterbelts play a crucial ecological role by modifying the distribution of soil water in farmland. However, whether and how water competition with crops near the shelterbelt edge influences soil microbial functions remains poorly understood. In this study, we combined stable hydrogen and oxygen isotope techniques with metagenomic sequencing, using a composite system of Populus alba var. pyramidalis and maize as the study object. The study encompassed multiple shelterbelt configurations as well as monoculture maize control plots. We systematically analyzed variations in water competition between shelterbelts and maize within a distance of 2H (H represents tree height) and evaluated their effects on soil microbial functions. The results showed that shelterbelts significantly reduced soil water content within 1H. Functional genes associated with glycine betaine, trehalose, and proline metabolism showed significant correlations with absolute water competition intensity (ACI) and proportional similarity (PS) (p < 0.05), but no significant correlation with soil water content (SWC). These variations reflected a microbial shift from short-term, stress-induced osmotic regulation toward long-term stable stress adaptation strategies. Glycolysis/Gluconeogenesis was downregulated, whereas the citrate cycle was upregulated in shelterbelt plots, suggesting a shift in microbial communities from rapid carbon input metabolism toward a metabolic strategy that maintains carbon flux and energy homeostasis. In summary, shelterbelts regulate microbial osmotic adjustment functions and carbon metabolic pathways by altering water competition patterns with crops, thereby providing a scientific basis for optimizing shelterbelt design and adaptive water management to balance efficient water use and soil ecological functions in arid agroecosystems.

Desert steppe ecosystems are highly vulnerable to aeolian erosion due to frequent winds and grazing disturbance. However, the synergistic effects and multi-level linkages among climate change, vegetation, and wind erosion remain unclear. Based on a 20-year grazing experiment (2004-2023) and an 11-year aeolian erosion monitoring program (2013-2023), this study examined four stocking rates: non-grazing control (CK), light (LG), moderate (MG), and heavy grazing (HG). Aeolian sediment was collected using BSNE samplers, and vegetation and climate variables were monitored during growing seasons. Structural Equation Modeling (SEM) revealed a hierarchical response of aeolian sediment flux across interannual variation, stocking rate, and collection height. Two synergistic pathways were identified: "precipitation-* vegetation characteristics-* aeolian sediment flux" and "stocking rate-* vegetation characteristics-* aeolian sediment flux." Precipitation reduced sediment flux in wet years by improving vegetation; stocking rate altered vegetation and modulated sediment flux in normal years; grazing amplified wind erosion in dry years, making wind speed the dominant driver. In conclusion, wind erosion mechanisms in desert steppes vary dynamically with precipitation and grazing intensity. Grazing disturbance is not the sole cause of erosion but interacts with multi-level factors and annual climate conditions. Critically, grazing amplifies erosion during drought years, which may be a key driver of grassland degradation in arid regions.

The arid regions of Northwest China (NWC) frequently experience compound drought-heatwave (CDHW) events during summer, where irrigated oases play a key role in mitigating extremes and sustaining agricultural productivity. However, the response of various oases to irrigation, irrigated water allocation strategy under CDHW remain insufficiently understood. Using convection-permitting and irrigation-diversified regional climate simulations, we evaluate climatic effects of different irrigated oases in NWC during CDHW. Results show that oasis irrigation significantly mitigates drought and heatwave, leading to reduction in 2 m air temperature (T) by 0.21 degrees C and an increase in 2 m relative humidity (RH) by 0.75%, accompanied by enhanced latent heat flux (LH) by 3.41 W m(-2), reduced sensible heat flux (HFX) by 1.42 W m(-2). Ranking of oasis effects about cooling and humidification efficiency due to irrigation is alluvial plain oases (APO) > mountain fan oases (MFO) > river valley oases (RVO) > intermontane corridor oases (ICO). Irrigation induces diurnally asymmetric circulation pattern characterized by a daytime "cold suction" mechanism and a nocturnal "cold discharge" process. In addition, a nonlinear response is identified, with optimal range of 40 (+/- 1.6) - 68.8 (+/- 1.6) mm and theoretically maximum oasis area 5000-8000 km(2), within which the oasis effects are most efficient to resist a 10-day CDHW event. These results further support irrigation supply that prioritizes APO and MFO, then guarantees the basic agricultural production of RVO and ICO if facing constrained water resources. This study provides guidance for optimizing irrigation and water allocation to maintain oasis effects and agricultural development in arid regions under extreme climate conditions.

The structural analysis of shelterbelts forms the foundation of their planning and management, yet the scientific and effective quantification of shelterbelt structures requires further investigation. This study developed an innovative heterogeneous analytical framework, integrating three key methodologies: the LeWoS algorithm for wood–leaf separation, TreeQSM for structural reconstruction, and 3D alpha-shape spatial quantification, using terrestrial laser scanning (TLS) technology. This framework was applied to three typical farmland shelterbelts in the Ulan Buh Desert oasis, enabling the first precise quantitative characterization of structural components during the leaf-on stage. The results showed the following to be true: (1) The combined three-algorithm method achieved ≥90.774% relative accuracy in extracting structural parameters for all measured traits except leaf surface area. (2) Branch length, diameter, surface area, and volume decreased progressively from first- to fourth-order branches, while branch angles increased with ascending branch order. (3) The trunk, branch, and leaf components exhibited distinct vertical stratification. Trunk volume and surface area decreased linearly with height, while branch and leaf volumes and surface areas followed an inverted U-shaped distribution. (4) Horizontally, both surface area density (Scd) and volume density (Vcd) in each cube unit exhibited pronounced edge effects. Specifically, the Scd and Vcd were greatest between 0.33 and 0.60 times the shelterbelt’s height (H, i.e., mid-canopy). In contrast, the optical porosity (Op) was at a minimum of 0.43 H to 0.67 H, while the volumetric porosity (Vp) was at a minimum at 0.25 H to 0.50 H. (5) The proposed volumetric stratified porosity (Vsp) metric provides a scientific basis for regional farmland shelterbelt management strategies. This three-dimensional structural analytical framework enables precision silviculture, with particular relevance to strengthening ecological barrier efficacy in arid regions.

The conversion of indigenous woodlands to agricultural lands has significantly altered nitrogen (N) cycling, impacting both ecosystem productivity and environmental health locally and globally. The relationship between cultivation duration and soil N availability and the mechanisms that drive these changes, however, remain unclear. In this study, we aimed to investigate how the duration of agricultural reclamation influences soil N cycling in the karst landscapes of southwestern China. We selected economic crops that have been cultivated for 1, 5, 15, and 30 years and conducted a regional survey using N-15 labeling and molecular biology techniques to assess the effects of cultivation duration on soil N cycling. Our results show that short-term reclamation (< 5 years) caused minimal changes in soil N dynamics, with little effect on the net production rates of NH4+ and NO3-. However, as cultivation duration increased, we observed progressive declines in mineralization, nitrification, and microbial immobilization rates of NH4+ and NO3-. This led to a substantial reduction in soil inorganic N availability (-39 % for NH4+ and -70 % for NO3-) and a significant increase in the mean residence time of NH4+ and NO3-, indicating a slower N turnover. Long-term reclamation (30 years) resulted in the most pronounced effects, reducing the soil's capacity to supply inorganic N by impairing soil organic matter input, degrading soil structure, and lowering soil pH. Key soil variables such as soil organic carbon content, pH, total N, and soil aggregate stability explained over 80 % of the variance in N turnover rates. Overall, our findings suggest that while short-term reclamation has little impact, long-term agricultural practices significantly impair soil N cycling and availability. Sustainable agricultural practices that enhance soil organic matter content and promote soil aggregate stability could help preserve soil health and maintain productivity in karst and similar regions worldwide.

Understanding the spatiotemporal patterns of soil moisture and salinity dynamics and their governing factors is essential for predicting salinization risks and developing mitigation strategies in arid agricultural landscapes. This study examined the vertical distribution (0-3 m) of soil water content (SWC), electrical conductivity (EC), and pH, and identified their dominant controls across bare sand dunes, nabkha dunes, and croplands of varying cultivation durations (2-5, 12-15, 25-30, and 40-50 years) in a desert-oasis ecotone of northwestern China. The results showed that SWC, EC, and pH generally increased with soil depth and were best described by quadratic or power functions. Bare sand dunes had the lowest values of all three parameters, while EC and pH peaked in nabkha dunes (188.20-636.83 mu Scm(-)(1) and 7.88-8.43, respectively), particularly those near the water area, where the early-stage cultivation may be more challenging. Conversion to cropland reduced surface (0-0.4 m) EC and pH by 7.3-34.7 % and 3.9-7.2 %, respectively, after 40-50 years of cultivation, in contrast, subsurface soil layers (0.4-3 m) exhibited stable EC and pH levels after long-term irrigation, with no significant changes between 25-30 and 40-50 years of cultivation (P > 0.05). However, subsurface salinity (0.4-1 m) in newly reclaimed croplands (2-5 years) tended to be higher than that in both nabkha dunes and older croplands, suggesting a potential risk of salinization in the new croplands, which require optimized irrigation. Soil texture was the dominant factor controlling SWC, while cultivation years primarily explained the variation in EC and pH. These findings reveal critical spatiotemporal dynamics in soil water-salt following land use change and offer guidance for optimizing irrigation practices to prevent secondary salinization in arid regions.

Lightning-ignited fires are the leading fire type in boreal forests, where early warning systems are essential for effective fire suppression and loss reduction. However, the prediction of lightning ignitions and the identification of contributing factors have not been thoroughly investigated in the boreal forest of northeast China, a region that experienced the most frequent lightning fires and the largest burned areas in the country. This study develops a prediction model using the eXtreme Gradient Boosting (XGBoost) algorithm. The model integrates the cases of igniting and non-igniting lightning, along with datasets of weather, soil, topography, vegetation, and lightning in 2019-2023. An optimized repeated random undersampling method was implemented to address the imbalanced population of the three cases. The most accurate classifier (MAC) was obtained from training 1000 XGBoost classifiers, which achieves a prediction accuracy of 88.7 %. The MAC performance remains robust when tested on individual lightning fire days and within the entire study period, indicating its reliablity for lightning ignition nowcasting. Using the Shapley Additive exPlanations (SHAP) framework, we quantified the relative contributions of wildfire variables and their marginal effects on the lightning ignition. Results indicate that low surface soil moisture (an indicator of fuel dryness) and low lightning density (associated with little precipitation) are the dominant factors for lightning ignition. Overall, the MAC significantly outperforms traditional fire danger rating indices, suggesting that weather conditions alone are inadequate for lightning ignition prediction, and the effects of surface soil moisture and lightning activity should be considered.