Search Results (1,774)

Pectin films are promising renewable materials for biodegradable coatings; however, their high hydrophilicity and limited resistance to ultraviolet (UV) radiation restrict practical applications. This work investigated the influence of kraft lignin (0–5 wt%) on the structure–property relationships of grape-derived pectin films before and after accelerated UV exposure. Structural organization (XRD and FTIR), photostability (CIELAB colorimetry and CIE chromaticity), wettability, water-vapor absorption, surface morphology, soil-burial disintegration, and integrated multifunctional performance were evaluated. Lignin improved resistance to UV-induced structural changes, reducing the relative loss of apparent crystallinity from 52.76% for neat pectin to less than 7% for films containing at least 0.1 wt% lignin, while substantially decreasing UV-induced color changes. Increasing lignin content also reduced surface wettability, water-vapor uptake, and soil-burial mass loss; nevertheless, all formulations exhibited more than 50% mass loss after 120 h of soil burial. Exploratory CRITIC–TOPSIS analysis identified Pec/Lig${}_1$ as the highest-performing formulation, whereas Pec/Lig${}_{0.1}$ provided the most compositionally efficient balance among photostability, moisture resistance, structural stability, soil-burial disintegration, and lignin consumption. These findings demonstrate that lignin governs the trade-offs among structural stability, photostability, moisture resistance, soil-burial disintegration, and additive consumption, establishing composition–structure–property–durability relationships that provide practical design guidance for candidate functional coatings for cellulose- and paper-based substrates. Full article

Intensive groundwater exploitation in the Wei River Basin (WRB) has caused severe depletion. While Gravity Recovery and Climate Experiment (GRACE) satellites monitor these changes, their coarse resolution fails to account for soil erosion-induced mass loss on the Loess Plateau limit basin-scale accuracy. To address this, we developed the groundwater storage model to dynamically downscale GRACE data to the resolution of 0.05° grid. This physically based model integrates Darcy’s law, water-balance principles, and an innovative correction for soil erosion mass migration. Validated against well data with maximum correlative coefficient of 0.73, the model reveals a severe groundwater decline of 55.89 × 10⁸ m³/year from 2003 to 2023. The high-resolution results successfully capture localized over-extraction hotspots in the Guanzhong Plain, showing a west-to-east decreasing gradient in groundwater storage along the Wei River channel. Furthermore, quantitative analysis indicates that human activities, including primarily agricultural and urban extraction, are the overwhelming drivers, accounting for over 80% of storage depletion. This framework provides a robust methodological reference for isolating groundwater signals in erosion-prone regions and supports refined water management in semi-arid basins. Full article

Saline water irrigation is a potential strategy to address agricultural water scarcity, but its effects on soil respiration and carbon balance are not well understood. To clarify these effects and promote the safe utilization of saline water resources, this study investigated five irrigation water salinity levels EC_iw: 1.3, 3.4, 7.1, 10.6, and 14.1 dS·m⁻¹ (i.e., 1, 2, 4, 6, 8 PSU; 1000, 2000, 4000, 6000, 8000 mg·L⁻¹) in a winter wheat–summer maize rotation during 2024–2025. The results indicated that saline water irrigation caused salt accumulation during the wheat season, whereas salt leaching occurred during the maize season. When EC_iw ≤ 3.4 dS·m⁻¹, no notable decreases were observed in dry matter accumulation, water productivity, and carbon emission efficiency for both crops. In contrast, when EC_iw > 3.4 dS·m⁻¹, the crop yields and net carbon input of the crop rotation system were suppressed to a considerable extent. Furthermore, under saline water irrigation, the average soil respiration rate decreased by 4.1–25.2% during the wheat growing season, while that for maize decreased by 7.4–30.7%. Soil respiration in wheat was negatively correlated with soil salinity and pH, and positively correlated with soil moisture (p < 0.01). In maize, soil respiration was negatively correlated with salinity (p < 0.01), and positively correlated with soil moisture (p < 0.05) and temperature (p < 0.01). The entropy-weighted TOPSIS model identified 3.4 dS·m⁻¹ as the appropriate irrigation salinity threshold for maintaining yield and carbon sink function in this rotation system. Full article

Abandoned floodplains are complex landscapes in boreal permafrost regions due to diverse biogeomorphic effects that are highly modified by permafrost aggradation and degradation. We compiled biophysical properties for 150 cores at 135 sites with depths up to ~4 m on the Tanana Flats in central Alaska and developed depth profiles for bulk density, moisture, organic carbon, pH, stable isotopes, radiocarbon age, and thaw strain. We found strong associations among biophysical components but also highly variable soil properties and ecological histories. We developed a conceptual model of the transition pathways and biophysical drivers among ecosystem types. Across sites, fluvial deposition was active from 9820 to 4290 ¹⁴C YBP, eolian silt and sand deposition prevalent from 3780 to 1890 YBP, and peat accumulation from 5330 YBP to present. Due to flat topography, water impoundment in depressions, groundwater, and ecological feedbacks, ecosystem-driven permafrost has a complex history of repeated aggradation and degradation resulting in highly fragmented landscapes. Recent thermokarst features had ages ranging from 20 to 920 YBP in collapse-scar bogs and from 50 to 250 YBP in collapse-scar fens. Abandoned floodplains with rapid thermokarst provide saturated environments for robust organic accumulation, with mean soil carbon stocks in the top 3 m being similar among thermokarst bogs (133 kg/m²), fens (108 kg/m²) and permafrost plateaus (115 kg/m²). This study contributes needed information on how permafrost dynamics and ground-ice characteristics influence landscape evolution and on the vulnerability of villages built on abandoned floodplains, infrastructure, and military use of training lands in boreal lowlands. Landscape fragmentation, complex palaeoecological histories, high spatial variability, and limited deep sampling of thermokarst features, however, restrict interpretation of how permafrost loss is affecting the soil carbon balance in an area where most permafrost will disappear in this century. Full article

This study examines how multiple dimensions of climate variability are associated with irrigation-related water productivity in the six Gulf Cooperation Council (GCC) countries over 2000–2023. Water productivity is measured as economic output generated per unit of freshwater withdrawal and is interpreted as an economy-wide proxy for water-use efficiency rather than a crop-specific biophysical measure. Using a balanced panel of 144 country-year observations, the study combines seven annual climate indicators from NASA POWER—temperature, precipitation, evapotranspiration, relative humidity, soil moisture, wind speed, and solar radiation—with socioeconomic and agricultural indicators from the World Bank. A two-way fixed effects model is estimated with controls for agricultural land, rural population, renewable energy consumption, carbon emissions, GDP per capita, and agricultural employment. The results show that temperature, evapotranspiration, wind speed, and solar radiation are negatively associated with water productivity, whereas precipitation, relative humidity, and soil moisture are positively associated with it. Soil moisture and temperature display the largest estimated effects among the climate variables in the baseline specification. The analysis further finds that the estimated climate–water-productivity relationship differs in magnitude between the pre-COVID (2000–2019) and post-COVID (2020–2023) periods. Interaction models indicate that soil moisture, precipitation, and relative humidity partially moderate the adverse effects of temperature and evapotranspiration. These findings remain broadly stable across alternative dependent variables, lagged climate specifications, alternative estimators, and leave-one-country-out analyses. The study contributes GCC-wide evidence on the joint and conditional effects of climate variability and highlights the importance of climate-informed irrigation scheduling, soil-moisture monitoring, and precision water-management technologies for strengthening agricultural resilience in arid environments. Full article

The growing environmental impact of petroleum-based plastic packaging has accelerated the development of biodegradable materials from renewable resources. In this study, cellulose extracted from wheat straw was regenerated into biodegradable films using calcium-ion crosslinking and glycerol plasticization. A Box–Behnken experimental design optimized cellulose content (0.35–0.5 g), calcium chloride concentration (200–800 nm), and glycerol concentration (0.5–1.5%) to produce films with balanced mechanical and barrier properties. The optimized film was characterized for its physicochemical, mechanical, optical, antioxidant, and biodegradation properties and evaluated for fresh grape packaging. The film exhibited favorable mechanical strength of 30.82 ± 4.70 MPa, controlled water vapor permeability of 0.59 ± 0.06 10⁻¹⁰ gm⁻¹ s⁻¹ Pa⁻¹, elongation at break of 4.36 ± 0.35%, moderate transparency of 22.95 ± 0.65% mm⁻¹ at 600 nm, and ultraviolet light-blocking capability, allowing only 9.57 ± 1.44% of UV-B at 300 nm, and an IC₅₀ value of 0.33, indicating moderate antioxidant potential, with 35% biodegradation after 37 days at a soil moisture of 24%. During ambient storage, grapes packaged with the film reached 15% weight loss by 13 days, while slowing changes in total soluble solids, pH, titratable acidity, total phenolic content, and vitamin C, and delaying visible quality deterioration. Compared with the uncovered control, packaged grapes maintained acceptable quality for approximately six additional days, reaching 15 days of storage. Unlike conventional polystyrene film, which promoted excessive gas accumulation and fruit cracking, the wheat straw cellulose film provided a semipermeable barrier that balanced moisture and gas exchange. The systematic optimization of these formulations, followed by comprehensive characterization of the optimized films, demonstrates the potential of wheat straw cellulose as a functional material for developing cellulose films as sustainable, biodegradable packaging materials for extending the postharvest quality of fresh produce. Full article

Warming is making drought and heat co-occur more often, intensifying compound stress on cropland in northern China’s drylands, where water scarcity makes further irrigation expansion untenable. On the Guanzhong Plain, a major grain-producing region, it remains unclear which irrigation conditions buffer cropland carbon–water productivity—the carbon assimilated per unit of water consumed—against such events. Using growing-season (March–October) remote sensing for 2016–2024, we identified the 2022 compound drought–heat event pixel by pixel and classified cropland as stable rainfed, transitional/mixed, or stable high-coverage irrigation from the pre-event (2016–2020) irrigated-area fraction and its persistence. In 2022, 88.9% of cropland experienced at least one compound dry–hot day, with dry–hot overlap 2.4 times the independence expectation. After balancing climate, terrain, soil, spatial position, and subpixel cropland fraction, stable high-coverage irrigation held no advantage in event-year resistance, post-event recovery, or overall resilience. Carbon assimilation remained above its pre-event level while carbon–water productivity fell, so the event cost water-use efficiency rather than carbon. Event-period root-zone soil-moisture change ranked first, and irrigated-area fraction last, among twelve random-forest predictors of resistance. We flagged 6722.3 km² of cropland for water-use audits and 2418.1 km² for supplemental irrigation; limited water should be allocated by realized moisture status, exposure, and resilience, not by irrigability. Full article

Water retention availability remains a primary constraint on both vegetation restoration and agricultural productivity across the Chinese Loess Plateau. Attapulgite (ATP) has considerable potential as a soil amendment for improving soil water retention and crop performance, yet its effectiveness is likely to depend on soil texture and climatic water availability. Here, we evaluated the effects of five ATP application rates (0%, 1%, 2%, 3%, and 4%, w/w) on soil hydraulic properties and maize (Zea mays L.) grain yield in three representative soils: clay loam, loam, and sandy loam. Soil water retention curves and field maize experiments were conducted to quantify the hydrological and agronomic responses to ATP addition. The classical van Genuchten (VG) model was further modified by incorporating ATP-dependent parameter relationships to better characterize the water retention behavior of ATP-amended soils. The modified model consistently provided a more accurate representation of the relationship between soil water content and matric suction than the original VG model. The derived soil hydraulic parameters were subsequently incorporated into the DSSAT cropping system model, which was calibrated and evaluated against field observations from Yangling in 2019 and 2020. The calibrated model was then used to simulate maize yield responses to ATP application from 2011 to 2020 at three representative sites: Yangling (clay loam), Changwu (loam), and Yan’an (sandy loam). Simulated yield responses varied markedly with soil texture and interannual climatic conditions. In clay loam, maize yield generally decreased with increasing ATP application, although positive responses occurred in relatively dry years. In sandy loam, ATP application generally increased maize yield across most years, whereas the loam soil exhibited stronger interannual variability in yield response. These contrasting responses indicate that the agronomic effectiveness of ATP is governed by the balance between enhanced soil water retention and local climatic water availability. Overall, the coupled soil hydraulic–crop modeling framework provides a mechanistic basis for developing site-specific ATP management strategies and highlights the importance of matching soil amendments to both soil texture and climatic conditions in water-limited agroecosystems. Full article

Surface energy partitioning regulates heat and water exchange between land and atmosphere and reflects alpine ecosystem responses to meteorological variation. Using radiation and meteorological data from November 2022 to October 2023, we compared adjacent alpine shrubland (Hulu 1) and alpine meadow (Hulu 2) ecosystems in the Qilian Mountains. Surface energy fluxes were estimated with a combined method based on surface energy balance, then evaluated with eddy covariance measurements. Path models examined direct and indirect environmental effects on turbulent fluxes. Standardized sensitivity coefficients based on evaporative fraction (EF) assessed seasonal responses of energy partitioning to environmental variation. Both ecosystems showed similar seasonal patterns, although flux magnitudes differed. Net radiation (R_n) followed a unimodal annual cycle and averaged 107.69 W m⁻² in the meadow and 89.36 W m⁻² in the shrubland. Sensible heat flux (H) peaked in May, with annual means of 60.22 and 51.68 W m m⁻². Latent heat flux (LE) peaked in July and averaged 49.12 and 38.58 W m m⁻². Soil heat flux (G) varied least, averaging −21.64 and −0.89 W m⁻². Path analysis identified R_n as the strongest control on turbulent fluxes. Its effect on H was weaker in the shrubland (0.92) than in the meadow (0.97), whereas its effect on LE was stronger in the shrubland (0.94) than in the meadow (0.71). Wind speed was positively related to H but negatively related to LE, with a stronger effect on H in the shrubland. Vapor pressure deficit (VPD) was negatively related to H but positively related to LE. Soil water content (SWC) had limited direct effects on turbulent fluxes at both sites. Sensitivity analysis showed higher overall EF sensitivity to environmental variation in the meadow during the growing season (0.510 vs. 0.228). Meadow EF was more sensitive to soil temperature (T_s) and SWC, whereas shrubland EF responded more strongly to VPD. Over the whole period, overall EF sensitivity was higher in the shrubland than in the meadow (0.439 vs. 0.353). These findings show that vegetation type and local environmental conditions jointly shape surface energy balance and energy partitioning in alpine ecosystems. Full article

Plant-derived methane (CH₄) has already been reported, but the factors that regulate its production are not fully documented. Few studies have considered the effects of blue light on plant-derived CH₄, but the role of salicylic acid in the process has not been studied. We examined the effects of two blue light levels (0 and 4 mW cm⁻²) and two salicylic acid concentrations (0 and 100 μL of 1 mM solution every other day) on canola (Brassica napus) growth and CH₄ emissions by growing plants under the experimental conditions for 21 days. Blue light raised CH₄ emission by 184% and increased stem height, leaf area ratio, shoot–root mass ratio, nitrogen balance index, leaf water potential, soil water potential, and leaf water content, but decreased stem diameter, plant biomass, specific leaf mass, net CO₂ assimilation, photochemical quenching, photosynthetic pigments, flavonoids, and anthocyanins. Salicylic acid did not have a significant effect on plant traits. Methane had both positive and negative relationships with plant traits; for example, CH₄ was negatively correlated with plant dry mass (r = −0.776, p = 0.003), protective compounds (r = −0.914, p = 0.000) and stomatal density (r = −0.677, p = 0.016), but positively correlated with nitrogen balance index (r = 0.621, p = 0.031). Our findings suggest that blue light negatively affects canola growth but increases CH₄ emissions, whereas the application of salicylic acid, as described in this study, was insufficient for mitigating stress in plants. Full article

Rice is a staple grain crop central to China’s food security. As the core production region of single-cropping rice, the middle and lower reaches of the Yangtze River face escalating high daytime and nighttime temperatures and compound drought–heat stress amid global warming. The accurate assessment of heat hazards is therefore pivotal for regional yield stability and disaster mitigation. Based on meteorological, remote-sensing, and soil data, together with county-level rice yield statistics from 150 major producing counties spanning 1991 to 2024 (5009 county-year calibration units), we first constructed a composite heat damage index (CHI) by integrating daytime harmful accumulated temperature (Ha), nighttime harmful accumulated temperature (HNa), and the Vegetation Health Index (VHI). We then implemented a gradient boosting decision tree (GBDT) machine learning framework in which yield loss was imposed as a physical constraint. This framework was benchmarked against convolutional neural network (CNN), random forest (RF), and support vector machine (SVM) models, with the Shapley additive explanations (SHAP) method used for attribution analysis and an independent temporal partitioning strategy applied for model validation. The results indicate the following: (1) compared to the single daytime heat damage index, the CHI elevated the yield correlation coefficient from 0.52 to 0.63; (2) with yield constraint calibration, the model attained a balanced accuracy of 92.6% and 94.0% consistency with historical disaster records; (3) regional heat hazard presents a spatial pattern of “high in inland areas and low in coastal areas,” with the heading–flowering stage as the critical sensitive period; and (4) high nighttime temperature accounts for approximately 20% of the model’s relative importance, with higher discriminative sensitivity for high-grade hazards, while the amplifying effect of water deficit on heat stress maintains a stable relative importance of around 16%. In this study, the coupled optimization of traditional assessment paradigms and data-driven approaches is achieved, providing a methodological reference for refined growth stage–specific heat hazard assessment. Its cross-regional portability and independent predictive validity require further validation. Full article

Giant foxtail is a common weed in foxtail millet fields, and continuous cropping of foxtail millet increases its occurrence. Rotating foxtail millet with sorghum is a major practice in the dry farming regions of northern China. Given this situation, this study combined Petri dish germination tests with pot experiments to clarify the allelopathic effects of water extracts from different sorghum parts on giant foxtail. Distilled water (SCK) was used as the control, and treatments included stock solution (S1), as well as 10× dilution (S2), 50× dilution (S3), and 100× dilution (S4) of water extracts prepared from sorghum roots, stems, leaves, and rhizosphere soil. The results showed that water extracts from all sorghum parts exhibited promotion of giant foxtail seed germination at higher dilutions and inhibition at lower dilutions. The S3 treatment of rhizosphere soil extract achieved a germination rate of 62.22%, which was significantly higher than that of the SCK by 40.00%. The germination energy of root extract S1 was only 4.00%, which was significantly lower than that of the SCK by 86.67%. The S3 treatment showed the strongest allelopathic promotion effect. All dilution treatments promoted the plant height, stem diameter, and above ground fresh and dry weight of giant Foxtail, and these effects increased initially and then stabilized over time. The root extract exhibited higher allelopathic activity than the other extracts. The activities of superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) first increased and then decreased as the dilution factor increased, while the S1 treatment inhibited enzyme activities and caused an imbalance in the antioxidant system. Sorghum root water extract had a significant effect on CAT activity in giant foxtail, with an increase of 98.82% under the S3 treatment compared with the SCK at 40 d. Malondialdehyde (MDA) content increased with decreasing dilution factor, and the undiluted extract induced membrane lipid peroxidation damage. In conclusion, the allelopathic effects of sorghum extracts on giant foxtail were closely related to the dilution level. Higher dilutions activated the antioxidant defense system and promoted growth, while lower dilutions disrupted enzyme system balance and exacerbated membrane damage. These findings provide basic data and theoretical support for the development and utilization of sorghum allelochemicals and for the green control of giant foxtail. Full article

Salinity is a growing problem for cereal cultivation because it imposes multiple stresses, including osmotic, ionic, nutritional, and oxidative constraints, on the crop. Sorghum (Sorghum bicolor L. Moench) is considered a climate-smart C4 cereal for food, feed, fodder, forage, and bioenergy, but recent studies indicate that salinity continues to hinder establishment, biomass formation, reproductive growth, and yield. This review compiles the literature on the impacts of salinity on sorghum from 2021 to 2026, with a focus on germination, vegetative growth, physiological and biochemical responses, ion homeostasis, genetic control, productivity, mitigation, and future breeding priorities. In total, 160 records were identified, 118 records were screened after duplicate removal, and 44 recent sources were included in the synthesis. Across comparable sorghum studies, saline/NaCl treatments of approximately 60–200 mM commonly reduced germination by about 20–40%, root and shoot elongation by 25–50%, and biomass by 20–55%, while tolerant genotypes generally maintained higher K⁺/Na⁺ balance, 40–60% greater biomass retention, or two- to five-fold stronger ion homeostasis indicators than sensitive lines under similar conditions. Salt stress also lowers leaf expansion, chlorophyll stability, gas exchange, dry matter accumulation, panicle fertility, and grain filling. Tolerant genotypes show greater antioxidant potential, osmotic adjustment, photosynthetic stability, and root system resilience. Recent omics and genome-wide association studies suggest that salinity tolerance in sorghum is polygenic and involves genes related to ion transport, stress signalling, antioxidant regulation, osmolyte metabolism, and growth maintenance. This review recommends a shift from descriptive trait lists to full-cycle field validation, multi-trait selection indices, and integrated packages combining breeding with seed priming, soil water management, amendments, and beneficial microorganisms. Full article

Korean pine (Pinus koraiensis) nut-timber plantations are important for both timber and seed production, yet optimal water and fertilizer management for mature cone-bearing stands remains poorly understood. A two-year field experiment was conducted to evaluate the effects of three fertilization levels (F1, F2, and F3, corresponding to N:P₂O₅:K₂O application rates of 50:75:25, 100:150:50, and 150:225:75 kg ha⁻¹, respectively) and three soil moisture regimes corresponding to 80%, 60%, and 40% of field capacity (W1, W2, and W3, respectively) on tree growth, cone yield, and soil physicochemical properties in approximately 35-year-old Korean pine plantations established on Albeluvisol at Maoer Mountain, northeastern China. Tree growth and cone yield generally followed the order F2 > F3 > F1 and W2 > W1 > W3, with F2W2 (N:P₂O₅:K₂O = 100:150:50kg ha⁻¹ and 60% of field capacity) consistently producing the best performance. Compared with the control (CK, no fertilizer application, rainfed under natural ambient conditions), F2W2 increased height, diameter, and crown width increments by 46.2%, 71.4%, and 65.6%, respectively, in 2023. Per-tree cone number, total cone mass, and total pine nut mass increased progressively across years, reaching increases of 88.5%, 100.6%, and 132.4%, respectively, in 2024. In contrast, thousand-seed weight showed relatively small changes and a delayed water–fertilizer interaction. Water–fertilizer coupling significantly altered soil physicochemical properties by reducing soil pH under the optimal treatment, while also regulating inorganic nitrogen availability and soil nutrient distribution. Nitrate nitrogen was highest under W2, whereas ammonium nitrogen peaked under W1. Total nitrogen was highest under F3W1, while available phosphorus and potassium accumulated under high fertilization combined with non-optimal soil moisture, but were lowest under F2W2, indicating enhanced nutrient uptake under the optimal treatment. Cluster analysis showed that nitrate nitrogen was positively associated with growth and yield variables. Overall, F2W2 provided the most favorable balance between stand productivity and soil nutrient status, representing an effective water–fertilizer management strategy for mature Korean pine nut-timber plantations on Albeluvisol. These findings provide a scientific basis for precision water and nutrient management in northeastern China. Full article

Atmospheric deposition in industrial basins of Central Asia is strongly influenced by local emissions and wintertime dispersion conditions. This study characterized snowpack at 63 sampling stations across Ust-Kamenogorsk, Kazakhstan, including operational background station 1, on 24–26 February 2025 after a 116-day accumulation period. Major ions were determined in a spatially distributed exploratory subset of 16 samples, and trace elements were measured in samples from all 63 stations by means of inductively coupled plasma mass spectrometry and optical emission spectrometry. Mean meltwater pH and total dissolved solids were 6.55 ± 0.34 and 37.3 ± 18.0 mg L⁻¹, respectively. Charge-balance errors for the 16 hydrochemical samples ranged from −0.3% to +0.7%. Using the contamination index based on exceedances of the current Kazakhstan water-quality thresholds, 48 stations had CI < 1, seven had CI = 1–3, and eight had CI > 3; the highest value (60.21) occurred at station 26. Principal component analysis showed that the first three components explained 53.6% of the variance and separated a broad mineral/industrial aerosol association from a Pb–Cd–Zn association consistent with non-ferrous metallurgy and mixed urban sources. Cadmium was therefore interpreted as the principal contributor to the MPC-normalized index at the most affected stations, rather than as the dominant component by absolute concentration. The dissolved fraction can be mobilized during spring melt, indicating a potential pathway to soils and receiving waters, although direct ecological or human-health risk was not quantified. Station-level point mapping and projection along the NW–SE axis showed localized multi-element maxima rather than a monotonic citywide gradient. Full article