Particulate nitrate pollution control in North China Plain and Northeastern United States: A comparison of formation mechanism and its response to gaseous pollutants.

Regulatory mechanisms of sulfur fertilization on photosynthetic physiology and yield formation in adzuki bean (Vigna angularis L.) in the North China Plain: A four-year field study based on genotypic differences

Trade-based environmental costs of small coal-fired boiler upgrading policy and the value-added benefits trade-off in the North China Plain

Closing maize yield gaps in North China plain: Based on plot-scale farmer survey and simulation

Coordinating food security and ecological pressures in the North China Plain: A Doughnut framework approach

Regional drivers and strategies for improving irrigation water productivity of winter wheat: A case study on the North China Plain

Abstract Analyzing spatial synchronization of dry wet abrupt alternation (DWAA) events is essential for developing suitable measures to mitigate the underlying damage of such events. In this study, two types of DWAA events, namely, dry–wet and wet–dry events, are identified during 1962–2022 over China, and their spatial connections and propagation patterns are investigated by constructing the undirected and directed networks based on event synchronization. Network measures are determined to analyze complex patterns within each network. The results indicate the widespread risk of DWAA events across China with a significant increase in the frequency of both dry–wet and wet–dry events. Undirected network analyses highlight important geographic regions for the synchronization of DWAA events, such as the central–southern North China Plain and Hexi Corridor for both dry–wet and wet–dry events and Northeast China only for dry–wet events. It is also suggested that dry–wet events are more synchronized and generally exhibit larger synchronization patterns compared to wet–dry events. By applying the Louvain method, nine communities are detected in the undirected networks of both dry–wet and wet–dry events, within which the events are more likely to occur synchronously. Directed network analyses reveal that source regions of DWAA event propagation are always located near sink regions, indicating that the propagation of these events is generally limited to a certain range. Additionally, regions with a high incidence of DWAA events largely correspond to source regions of propagation. Moreover, DWAA events exhibit unique propagation patterns in different parts of China, such as east–west propagation in Northwest China, westward propagation in Southeast China, and northward propagation in Southwest China.

Optimizing tillage and fertilization practices is of vital importance for enhancing soil carbon retention, improving soil quality and increasing crop productivity in the intensive wheat (Triticum aestivum L.)–maize (Zea mays L.) double cropping system (WM). However, the combined effects of subsoiling (ST) and liquid manure (LM) application on yield sustainability and the dynamic changes in labile organic carbon (LOC) fractions (LOCs) remain insufficiently quantified in WM in the North China Plain (NCP). A two-year field experiment evaluated the responses of grain yields, the sustainable yield index (SYI), soil organic carbon (SOC), LOCs, C pool management indexes (CPMIs), and the soil quality index (SQI) to both patterns of tillage [conventional shallow rotary tillage (RT) and ST] and fertilization [conventional fertilization (CF), LM broadcast (LMB), and LM injection (LMI)] in WM in the NCP. Compared with RT, ST significantly enhanced crop grain yields (3.5~4.1%) and the annual SYI (4.1%) (p < 0.05). The contents of SOC, total labile OC (TLOC), high LOC (HLOC), and medium LOC (MLOC) and the values of SQI were higher in soil layers at both 0–20 cm and 20–40 cm under ST than those under RT. Compared with CF, LMI significantly enhanced grain yields (5.8~6.1%) and the annual SYI (5.4%). LMI significantly increased the contents of SOC, TLOC, HLOC, and MLOC and the SQI values in both soil layers relative to CF, while no significant difference was observed for grain yields, the annual SYI, and the SQI between LMB and CF. The higher contents of SOC and LOC led to an increase in the values of CPMIs based on TLOC (TCPMI), HLOC (HCPMI), and MLOC (MCPMI). The combination of both ST and LMI enhanced SOC retention through the increase in recalcitrant organic carbon (ROC) content and the transformation process of LOCs. It was obvious that HLOC and MLOC affected SOC, HCPMI, and MCPMI in the soil layers at both 0–20 cm and 20–40 cm, and thus can be regarded as sensitive indicators reflecting the dynamic changes in SOC and soil quality. Therefore, the combination of subsoiling and liquid manure injection can promote labile OC transformation, SOC retention, soil quality, and yield sustainability, providing an effective management strategy for the achievement of sustained agricultural production in the NCP or other regions with similar conditions.

Abstract Fogs formed by aerosol activation in supersaturated air often cause extremely poor visibility, yet accurate prediction remains challenging and models typically account for only fog droplet extinction. The role of fog interstitial aerosols has remained largely unexplored due to limited observational capabilities. Here, we developed an advanced optical instrument capable of online measurements of scattering and hygroscopic properties for both interstitial and activated aerosols, enabling direct determination of aerosol hygroscopicity and effective supersaturation in fogs and clouds. A new method is together proposed to quantify the light scattering enhancement of interstitial aerosols under supersaturation. Observations on the North China Plain reveal that hygroscopic growth of interstitial aerosols dominates fog visibility degradation, contributing on average >85% of total extinction, depending on fog water content. These results highlight the critical role of interstitial aerosols in fog visibility reduction and their potentially significant contribution to radiative effects in clouds with low water content.

Winter wheat is a major food crop in China, with the North China Plain (NCP) serving as the primary production region and playing a critical role in national food security. However, long-term, high-resolution winter wheat maps for this region remain limited. This study presents a 30 m resolution winter wheat distribution dataset for the NCP (WheatMapNCP) from 2000 to 2024, generated by combining automated training sample generation with a random forest (RF) classifier. A stratified random sampling framework was used to estimate unbiased winter wheat area. Validation results show that the produced maps achieved an average overall accuracy (OA) of 95.98 ± 1.15%, and an average F1 score of 86.4%. The estimated planted areas show a consistent temporal trend with official statistics, and the mapped areas show strong correlation to statistics at the provincial (R² = 0.97-0.98) and municipal (R² = 0.84-0.96) levels. The dataset not only provides long-term, high-quality support for monitoring winter wheat dynamics, but also offers a reliable approach for generating timely, transparent wheat area estimates based on satellite data.

Agricultural soils are vital for reducing atmospheric CO2; however, the effectiveness of farmland carbon sequestration, including soil organic carbon (SOC) and inorganic carbon (SIC), typically requires a lengthy period and varies with different farming practices. In a long-term study on the North China Plain, SOC and SIC changes due to farming practices involving N fertilization, organic materials, irrigation, and no-tillage were tracked. Four experimental treatments, including no N fertilizer input (CK), local farmer operation (FRM), optimized farming (OPT), and no-tillage (NoT), were selected for the study. From 2008 to 2024, the fertilized treatments sequestered SOC at rates of 0.35-0.63 Mg C ha-1 yr-1 in the 0-20 cm layer, which quadrupled in the 0-100 cm layer. Long-term high irrigation with N fertilization accelerated the leaching of SIC into the subsoil, and SIC losses ranged from 0.46 to 0.71 Mg C ha-1 yr-1 at 0-20 cm and from 1.88 to 2.42 Mg C ha-1 yr-1 at 0-100 cm. Organic materials and N fertilization interactively help sequester SOC, but excessive organic material input results lower conversion efficiency. Crucially, the substantial depletion of SIC across the whole profile largely counteracted the observed SOC gains, leading to a diminished or even negative net carbon balance. Ultimately, this study reveals that failing to account for whole-profile SOC-SIC co-dynamics leads to an overestimation of carbon sequestration in intensive agricultural systems, highlighting the necessity of integrated accounting for accurate climate mitigation assessments.

More frequently extreme precipitation delayed sowing window of winter wheat (Triticum aestivum L.) in North China Plain (NCP), which could change wheat phenological development, threatening yield formation. Widely, increased seeding rates were a proposed strategy to maximize potential yields. There is a clear need to examine the effects of delayed sowing and increased seeding rates on key wheat parameters, including phenology, growth and development. A 2-year field experiment was conducted with three sowing dates (conventional date, Con; delayed 7 days, D7; delayed 14 days, D14) and two seeding rates (250 seeds m-2, Nor; 310 seeds m-2, Inc). Results showed that without abundant pre-winter photothermal resources, yields under delayed sowing decreased by 7.60% (D7) and 18.04% (D14) compared with Con. However, Inc could alleviate and even reverse the yield loss caused by delayed sowing, which primarily was due to 29.95% higher pre-winter population and 9.40% more final spikes than Nor. Additionally, post-winter thermal accumulation under delayed sowing increased by 24.57-72.62 d °C compared to Con, which ensured higher tillers improvement from overwintering to jointing, increased relative growth rate by 38.52-109.69% compared to Con after jointing and prolonged effective grain-filling duration. Notably, compared with Nor-Con, the Inc-D7 effectively balanced crop population and individual characteristics, thereby achieved a 101.82% reversal in aboveground biomass accumulation and a 7.03% yield increase. Inc-D7 combination established yield resilience by establishing optimal population and adaptive growth regulation, which provided valuable information to secure production stability in the NCP agricultural system to cope with climate changes. © 2026 Society of Chemical Industry.

As water resources are becoming increasingly scarce in the North China Plain, irrigation strategies that simultaneously improve grain yield and reduce irrigation water input are needed for winter wheat (Triticum aestivum L.) production. Current irrigation decision rules are based either on fixed soil moisture thresholds or on evapotranspiration (ET)-based ratios applied uniformly across the growing season, limiting their flexibility for growth stage-specific irrigation management. In this study, a multi-objective simulation optimization framework was developed to jointly optimize soil moisture lower control limits (irrigation trigger thresholds) and evapotranspiration-based irrigation replenishment ratios across key winter wheat growth stages. The framework integrated the AquaCrop-OSPy crop model with the PyFAO56 soil moisture balance, irrigation scheduling model and the NSGA-II evolutionary optimization algorithm. A field experiment was conducted during the 2024–2025 growing season in Laoling City, Shandong Province, China, employing a four-dense–one-sparse strip cropping pattern with two irrigation treatments: T1 (subsurface sprinkler irrigation) and T2 (shallow subsurface drip irrigation). The AquaCrop-OSPy model was calibrated and validated using measured canopy cover, aboveground biomass, grain yield, and soil moisture content in the 0–60 cm soil layer. Simulated canopy cover and grain yield showed good agreement with observations, with the coefficient of determination (R2) ranging from 0.87 to 0.94. For grain yield, the normalized root mean square error (NRMSE) ranged from 2.24% to 3.75%, and the root mean square error (RMSE) ranged from 0.29 to 0.54 t·ha−1. For aboveground biomass, R2 was 0.99, while RMSE ranged from 1.02 to 1.11 t·ha−1, and NRMSE ranged from 14.25% to 15.49%. The PyFAO56 irrigation strategy model simulated average root-zone soil-moisture dynamics with satisfactory accuracy, with an R2 of 0.86 and an RMSE of 5%. Multi-objective optimization (maximizing yield while minimizing irrigation volume) generated 23 Pareto-optimal irrigation strategies, with irrigation volumes ranging from 51 to 128 mm, corresponding yields ranging from 9.8 to 10.8 t·ha−1, and irrigation water use efficiency (IWUE) ranging from 0.08 to 0.19 t·ha−1·mm−1. Correlation analysis within the Pareto set indicated that soil-moisture control lower limits during the regreening–jointing stage and higher soil-moisture control lower limits during the flowering–maturity stage were key controlling factors for achieving high yields and irrigation water use efficiency. The Entropy-Weighted Ranked Minimum Distance method identified an optimal irrigation scheme involving two irrigations (one at the end of the jointing stage and another at the beginning of the grain filling stage) involving an irrigation depth of 75 mm, achieving a simulated yield of 10.4 t·ha−1 and an IWUE of 0.16 t·ha−1·mm−1. The proposed AquaCrop-PyFAO56-NSGA-II framework provides a flexible, process-based workflow for jointly optimizing irrigation control thresholds and evapotranspiration-based irrigation replenishment ratios across different winter wheat growth stages. Under the monitored conditions of the 2024–2025 wet season, the framework identified a two-irrigation strategy that balanced grain yield and irrigation input. This study should, therefore, be regarded as a proof-of-concept evaluation conducted in a well-instrumented single-site field setting rather than as a universally transferable recommendation. Because model calibration, within-season validation, and optimization were all based on one wet growing season at one site, the derived stage-specific thresholds, Pareto front, and S5 recommendation are most applicable to hydro-climatic conditions similar to the study year and should be further tested across contrasting year-types and locations before broader extrapolation.

In the North China Plain (NCP), wind and rain during the grain-filling period of winter wheat can cause lodging. The second basal internode (I2), a key load-bearing structure, plays a central role in yield stability. This study, under a constant nitrogen (N) application rate of 270 kg ha-1, aimed to clarify how nitrogen basal-to-topdressing ratios regulate I2 characteristics to balance lodging resistance and yield increase. Field experiments were conducted across two seasons with three cultivars and three nitrogen split ratios (5:5, CK; 3:7, N1; and 7:3, N2). Dynamic measurements of I2 mechanical properties, morphology, anatomy, and composition were taken, and structural equation modeling (SEM) was used for analysis. Results showed that the culm lodging resistance index (CLRI) decreased by 41.8% from flowering to milk stage under all treatments, with CLRI at the milk stage of lodging treatments between 0.11 and 0.15. SEM supported a composition-structure-lodging resistance-yield chain, with CLRI as the key mediator. The N1 treatment significantly improved CLRI at all stages and increased yield by 12.2% compared to CK, making it a recommended nitrogen strategy for improving both yield and lodging resistance. These findings provide agronomically applicable nitrogen management guidelines for high-yield winter wheat systems.

A multiyear concentration and flux-based O3 risk assessment of winter wheat in China: Trends and drivers.

Changes in human diets and cropping systems have led to a growing global dependence of agriculture on pollination, but pollinators are experiencing decline worldwide. Key stressors contributing to pollinator decline include natural habitat loss, a reduction in flower resources, and exposure to pesticides. In this study, we investigated effects of land use and estimated agrochemical use (fertilizer, biocides and plant growth regulators) on the abundance and diversity of pollinators across 24 landscape sites in the North China Plain using data from pan trapping across three seasons. We quantified agrochemical use as the average use intensity in agricultural production land (comprising arable land, orchards, agroforestry, and planted trees) and the landscape-wide exposure. The most abundant potential pollinators were bees (mainly Halictidae) and flies (mainly Muscidae and Syrphidae). Pollinator abundance, diversity and species composition were significantly affected by sampling season, with higher abundance and species diversity in autumn than in spring and summer. Pollinator abundance was positively associated with the proportion of arable land but negatively related with the proportion of orchard land and the agrochemical use intensity in agricultural production land and to the landscape-wide agrochemicals use. Overall, this study uncovered a weak signal of agrochemical use but a strong effect of season on pollinator diversity in the landscape setting of the North China Plain. Lower agrochemical use and a greater proportion of arable land were associated with higher abundance of some pollinator species in this intensive cereal production region. Results suggest that in the context of the North China Plain, pollinator abundance might be shaped more by aphid populations that support dominant species of hoverflies and by bare soil that favours nesting of wild bees, rather than by floral resources. Findings suggest that reducing agrochemical use intensity in agricultural production land, especially in orchards and other systems with trees, might facilitate pollinator conservation.

How does peanut yield fluctuate under irrigation practices and precipitation anomalies? Modelling insights from the North China plain

Insights into the accumulation and potential risks of metal(loid)s in Flos Sophorae Immaturus in a typical non-ferrous metal smelting region in the North China Plain

Irrigation-induced changes in rhizosphere and bulk soil properties shape microbial communities and functions in a winter wheat–summer maize system

Distinct molecular characteristics of humic-like substances (HULIS) in cloud water under land and marine influences.