Search Results (117)

Climate change is expected to increase the frequency of extreme soil moisture events, such as winter waterlogging followed by spring drought, particularly in temperate regions of Europe, North America and Northeast China. While N₂O emissions from paddy soils under waterlogging and subsequent drainage have been widely studied, knowledge of upland arable soils under wheat cultivation remains limited. We hypothesized that: (1) in upland soils, combined waterlogging and drought reduces N₂O emissions compared to continuous waterlogging, and (2) plant presence mitigates soil nitrate accumulation and N₂O emissions across different moisture regimes. A greenhouse experiment was conducted using intact upland soil cores with and without wheat under four moisture treatments: control (60% water-holding capacity, WHC), drought (30% WHC), waterlogging, and waterlogging followed by drought. Daily and cumulative N₂O fluxes, soil mineral nitrogen (NH₄⁺-002DN and NO₃⁻-N), and total nitrogen uptake by wheat shoots were measured. Prolonged waterlogging resulted in the highest cumulative N₂O emissions, whereas the transition from waterlogging to drought triggered a sharp but transient N₂O peak, particularly in soils without plants. Wheat presence consistently reduced N₂O emissions, likely through nitrate uptake, which limited substrate availability for incomplete denitrification. Moisture regimes strongly affected nitrate dynamics, with drought promoting nitrate accumulation and waterlogging enhancing nitrate loss. These findings highlight the vulnerability of upland soils in regions prone to seasonal moisture extremes. Effective management of soil moisture and nitrogen, including the promotion of plant growth, is essential to mitigate N₂O emissions and improve nitrogen use efficiency under future climate scenarios. Full article

Water scarcity poses a critical constraint to sustainable agriculture, particularly in small-scale systems that rely on traditional irrigation methods. Although organic matter (OM) is known to enhance soil structure and water-holding capacity, quantitative evidence regarding optimal OM levels and their interaction with microbial activity in agroecological contexts remains limited. This study evaluates the effect of different OM contents (2.37%, 3.42%, 5.55%, 7.89%, and 9.43%) on infiltration, moisture retention, and microbiological dynamics in 129 agroecological plots located in the northern highlands of Ecuador. Field and laboratory assessments revealed that intermediate OM levels (between 3.42% and 5.55%) optimize available water retention (up to 14.78%) and stabilize infiltration. In contrast, excessive OM levels (>7.9%) decrease retention efficiency and increase leaching risk. Microbial activity showed a positive correlation with OM up to a certain threshold, beyond which fungal and yeast activity declined under field conditions. The results underscore the importance of managing OM within an optimal functional range to improve irrigation efficiency, enhance microbial resilience, and support water sustainability in agroecological production systems. Full article

In the ecologically fragile western Shanxi Loess region, stand density regulation of artificial Robinia pseudoacacia L. forests plays a crucial role in sustaining the water regulation functions of the litter-soil system, yet multi-scale mechanistic analyses remain scarce. To address this gap, we established six stand density classes (ranging from 1200 to 3200 stems/ha) and quantified litter water-holding traits and soil physicochemical properties. We then applied principal component analysis (PCA) and structural equation modeling (SEM) to examine density-litter-soil relationships. Low-density stands (≤2000 stems/ha) exhibited significantly higher litter accumulation (6.08–6.37 t/ha) and greater litter water-holding capacity (maximum 20.58 t/ha) than the high-density stands (p < 0.05). Soil capillary water-holding capacity decreased with increasing density (4702.63–4863.28 t/ha overall), while non-capillary porosity (5.26–6.21%) and soil organic carbon (~12.5 g/kg) were higher in high-density stands (≥2800 stems/ha), reflecting a structural-carbon optimization trade-off. PCA revealed a primary hydrological function axis with low-density stands clustering in the positive quadrant, while high-density stands shifted toward nutrient-conservation traits. SEM confirmed that stand density affected soil capillary water-holding capacity indirectly through litter accumulation (significant indirect path; non-significant direct path), highlighting the central role of litter quantity. When density exceeded ~2400 stems/ha, litter decomposition rate decreased by ~56%, coinciding with capillary porosity falling below ~47%, a threshold linked to impaired balance between water storage and infiltration. These findings identify 1200–1600 stems/ha as the optimal density range; in this range, soil capillary water-holding capacity reached 4788–4863 t/ha, and available phosphorus remained ≥2.1 mg/kg, providing a density-centered, near-natural management paradigm for constructing “water-conservation vegetation” on the Loess Plateau. Full article

This study developed an innovative model integrating straw subsoil deep burial (SD) and mixing plow to mitigate albic soil’s physical and chemical constraints and enhance crop yield. A field experiment with four treatments, including conventional tillage (CT), straw mulching (SM), straw subsoil deep burial (SD), and straw burning (SR), was conducted to assess impacts on soil enzyme activity, nutrient dynamics, crop yield, and soil physical properties. Results showed that SD treatment significantly improved albic soil properties compared to conventional tillage: catalase activity in the albic horizon decreased by 13.51%, reducing peroxide toxicity. In the albic horizon, alkaline hydrolysis nitrogen, total nitrogen, available phosphorus, total phosphorus, available potassium, total potassium, and organic matter increased by 29.98%, 58.70%, 36.86%, 20.46%, 5.00%, 21.70%, and 40.46%, respectively. Correspondingly, maize and soybean yield under SD reached 8686.6 kg/ha and 2245.3 kg/ha, increasing by 15.39% and 19.94% compared to CT, respectively. Additionally, SD treatment improved physical properties of the albic horizon: soil hardness reduced by 43.56%, with enhanced water-holding capacity, permeability coefficient, porosity, and hydraulic conductivity. Its findings not only boost agronomic productivity by improving crop yields but also support environmental sustainability by enhancing soil fertility, which is of great significance for ensuring food security. Full article

Biochar (BC), a carbonaceous material derived from biomass pyrolysis, exhibits a wide range of physicochemical properties, including a high cation exchange capacity, porosity, and specific surface area, which make it a highly valuable amendment for soil enhancement and environmental sustainability. As BC has shown strong potential to remediate soils, enhance their fertility, and increase crop productivity, it can successfully be used as a soil remediation factor. Additionally, it can play a critical role in carbon sequestration and climate change mitigation, revealing a high sorption capacity, multifunctionality, and long-term persistence in soils, where it can remain stable for hundreds to thousands of years. The present systematic review aims at presenting the dynamics of BC when incorporated into a soil system, focusing on its pH, water-holding capacity, aeration, microbiota, and carbon and nutrient availability across various case studies, particularly in acid, saline/sodic, and heavy metal-contaminated soils. Given the variability in BC performance, robust, long-term field-based research is essential to validate the current findings and support the development of targeted and sustainable biochar applications. Full article

Manure-derived biochar is a promising soil amendment, though its effectiveness is often constrained by limited structural stability and inconsistent nutrient retention. This study evaluated how the pyrolysis method (pre- vs. post-pyrolysis) and rate (5%, 10%, 20%, and 30% w/w) of bentonite incorporation influence the physicochemical properties, nutrient availability, and carbon stability of manure-derived biochar. Scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS) analyses revealed that pre-pyrolysis addition enhanced mineral integration, with silicon and aluminum contents increasing by up to 500% and 600%, respectively, while carbon content decreased by up to 34%. Water holding capacity (WHC) improved by approximately 102% with 5–10% bentonite, and carbon stability more than doubled (≥100% increase) at moderate application rates under pre-pyrolysis treatment. However, nitrate (NO₃⁻) and potassium (K) availability declined by up to 89% and 47%, respectively, in pre-pyrolysis treatments due to strong nutrient immobilization. In contrast, post-pyrolysis bentonite addition increased NO₃⁻ by ~44% and K by ~29%, while phosphorus (P) availability rose by 133% at 30% bentonite. Principal component analysis (PCA) showed a clear distinction between pre- and post-pyrolysis bentonite-treated biochar. Pre-pyrolysis treatments were linked to higher pH, WHC, and carbon stability, while post-pyrolysis treatments were associated with greater nutrient availability (e.g., NO₃⁻, and K levels) and higher EC. These findings underscore the importance of the pyrolysis method, showing that pre-pyrolysis bentonite incorporation strengthens biochar’s structural integrity and long-term carbon sequestration potential, whereas post-pyrolysis addition enhances immediate nutrient availability. This duality enables the development of targeted biochar formulations tailored to specific agronomic needs—whether for sustained soil improvement or rapid fertility enhancement in climate-smart and sustainable land management systems. Full article

The application of soil organic amendments is a well-established approach to enhancing soil fertility; yet the effects of poultry feather hydrolysate (PFH) on temperate coarse-textured agricultural soils remain underexplored. A six-month microcosm experiment was conducted to determine the effects of PFH in different states (liquid or solid) and addition rates (none, low, or high; i.e., 0, 4, or 8 t dw ha⁻¹, respectively) on microbial activity, nutrient availability and retention, and organic matter (OM) stabilization in two coarse-textured soils (loamy sand or sandy loam). Sandy loam soil exhibited a stronger response to PFH application, supporting 20% higher microbial activity, 35% higher nutrient retention, and 89% higher OM content in soil aggregates compared to loamy sand soil, reflecting enhanced OM stabilization. Moreover, PFH in the liquid state demonstrated more prolonged microbial activity and more sustained release of nutrients compared to the solid state. Finally, at the end of incubation, the high addition rate of PFH significantly increased soil nutrient content by 106%, while the low addition rate limited the increase to 39%, both compared to the no addition rate. Overall, the results suggest that PFH, particularly in the liquid state and at the high addition rate, serves as an effective soil organic amendment, enhancing microbial activity and soil fertility while emphasizing the importance of soil texture in optimizing its application. Full article

In arid agricultural production, exploring suitable water-saving irrigation strategies and analyzing their water-saving mechanisms are of great significance. Alternating partial root-zone drying irrigation (APRI), a water-saving strategy, enhances the water use efficiency (WUE) of alfalfa (Medicago sativa L.) This paper aims to clarify the physiological mechanisms by which the APRI method enhances the physiological WUE of alfalfa, as well as the differences between this water-saving irrigation strategy, conventional irrigation (CI), and their water deficit adjustments, in order to seek higher water use efficiency for alfalfa production in arid regions. In this experiment, alfalfa was used as the research subject, and three irrigation methods, CI, fixed partial root-zone drying (FPRI), and APRI, were set up, each paired with three decreasing moisture supply gradients of 90% water holding capacity (WHC) (W1), 70% WHC (W2), and 50% WHC (W3). Samples were taken and observed once after every three complete irrigation cycles. Through a comparative analysis of the growth status, leaf water status, antioxidant enzyme activity, and osmotic adjustment capabilities of alfalfa under different water supplies for the three irrigation strategies, the following conclusions were drawn: First, the APRI method, through artificially created periodic wet–dry cycles in the rhizosphere soil, provides pseudo-drought stress that enhances the osmotic adjustment capabilities and antioxidant enzyme activity of alfalfa leaves during the early to middle phases of irrigation treatment compared to CI and FPRI methods, resulting in healthier leaf water conditions. Secondly, the stronger drought tolerance and superior growth conditions of alfalfa under the APRI method due to reduced water availability are key factors in enhancing the water use efficiency of alfalfa under this strategy. Full article

Coal gangue is a fine-grained mineral with nutrient content, which can be used as a potential soil amendment. Nevertheless, current research on using coal gangue to improve soil water and support plant growth is still insufficient. In this study, coal gangue powder (CGP) was added to aeolian sandy soil. We compared the soil hydraulic properties and plant growth of original aeolian sandy soil (CK) and different CGP application rates (10% and 20%). The results indicated that the application of CGP transformed the soil texture from sandy to loamy, significantly reduced soil bulk density and saturated hydraulic conductivity (Ks) values, altered the soil water characteristic curve, enhanced soil water-holding capacity, and increased plant-available water. Compared with the CK group, the emergence rate of alfalfa seeds increased from approximately 50% to over 70% after CGP application. During the growth process, CGP application significantly elevated the net photosynthetic rate, transpiration rate, and stomatal conductance of alfalfa leaves. Rapid fluorescence kinetics monitoring of leaves demonstrated that alfalfa treated with CGP had a higher efficiency in light energy utilization. However, the photosynthetic capacity of leaves did not improve as the CGP application rate increased from 10% to 20%, suggesting that excessive CGP addition did not continuously benefit plant gas exchange. In conclusion, CGP application can improve the soil hydraulic properties of aeolian sandy soil and support plant growth and development, which is conducive to reducing the accumulated amount of coal gangue, alleviating plant water stress, and promoting ecological restoration in arid mining areas. We recommend a 10% addition of coal gangue powder as the optimal amount for similar soils. Full article

Michelia macclurei, a valuable native broad-leaved species with good ecological and economic benefits and a key afforestation tree in South China, is facing progressive stand degradation and soil fertility decline with age. To investigate age-dependent dynamics of stand structure and soil properties, this study examined five stands (5, 10, 15, 20, and 42 a) in Yunfu City, Guangdong Province. The results revealed that (1) spatial distribution shifted from aggregated in young stands (5–10 a) to random in mature stands (42 a), with diameter and height class distributions becoming more diverse with age. Notably, topsoil (0–20 cm) in near-mature stands (15–20 a) exhibited not only significantly higher capillary porosity, non-capillary porosity, and water-holding capacity compared to young stands but also increased bulk density, indicating soil physical degradation. (2) Soil nutrient decline was observed in over-mature stands (42 a), characterized by a reduction in soil total nitrogen to 1.08 ± 0.06 g·kg⁻¹ and total phosphorus to 0.16 ± 0.02 g·kg⁻¹ in the topsoil (0–20 cm layer), suggesting age-related soil nutrient degradation. (3) Correlation analysis revealed a significant negative correlation between total potassium content and crown uniformity indices (p < 0.01), while available phosphorus was significantly positively correlated with crown and tree growth (p < 0.05). These findings provide critical insights for developing stage-specific management strategies in Michelia macclurei plantations. Full article

Ornamental plant growing is carried out in relatively small areas compared to other agricultural production areas, but the use of basic inputs such as water and fertilizer is intensive. Quality in cyclamen and for other similar ornamental plants is related to the amount and quality of the flowers. Irrigation and fertilization are very effective applications of these parameters. This study was conducted in Türkiye to detect the effects of different irrigation programs and nitrogen doses on Cyclamen persicum Mill. in 2023–2024. There were 12 treatments in total. Three different irrigation programs were used. When 20% (I₁), 40% (I₂), and 60% (I₃) of the available water holding capacity (AWHC) in the mixed soil were used, the irrigation water was applied in each irrigation until the available soil water reached the field capacity. There were four nitrogen doses for each irrigation program: N₀: 0, N₁: 10 kg N da⁻¹, N₂: 20 kg N da⁻¹, and N₃: 30 kg N da⁻¹. All the parameters were affected negatively by water stress. The 20 kg da⁻¹ nitrogen doses increased the number of flowers. Increasing water stress levels negatively affected the Pn. The zero nitrogen dose treatments (N₀) provided the lowest average Pn with 7.53 μmol m⁻² s⁻¹. The I₁ (frequency irrigation) irrigation program and N₃ nitrogen dose can be applied together to obtain the best vegetative growth. As another option to obtain the most generative growth, the I₁ (frequency irrigation) irrigation program and the N₂ nitrogen dose can be applied together. Full article

Within-field soil physical and chemical heterogeneity may affect spatio-temporal crop performance. Managing this heterogeneity can contribute to improving resource use and crop productivity. A simulation experiment based on comprehensive soil and crop data collected at the patchCROP landscape laboratory in Tempelberg, Brandenburg, Germany, an area characterized by heterogeneous soil conditions, was carried out to quantify the impact of within-field soil heterogeneities and their interactions with interannual weather variability on crop yield variability in summer and winter crops. Our hypothesis was that crop–soil water holding capacity interactions vary depending on the crop, with some crops being more sensitive to water stress conditions. Daily climate data from 1990 to 2019 were collected from a nearby station, and crop management model inputs were based on the patchCROP management data. A previously validated agroecosystem model was used to simulate crop growth and yield for each soil auger profile over the 30-year period. A total of 49 soil auger profiles were classified based on their plant available soil water capacity (PAWC), and the seasonal rainfall by crop was also classified from lowest to highest. The results revealed that the spatial variability in crop yield was higher than the temporal variability for most crops, except for sunflower. Spatial variability ranged from 17.3% for rapeseed to 45.8% for lupine, while temporal variability ranged from 10.4% for soybean to 36.8% for sunflower. Maize and sunflower showed a significant interaction between soil PAWC and seasonal rainfall, unlike legume crops lupine and soybean. As for winter crops, the interaction was also significant, except for wheat. Grain yield variations tended to be higher in years with low seasonal rainfall, and crop responses under high seasonal rainfall were more consistent across soil water categories. The simulated results can contribute to cropping system design for allocating crops and resources according to soil conditions and predicted seasonal weather conditions. Full article

The use of water-efficient soil amendments has gained increasing importance in agriculture, particularly in regions facing water scarcity. So, this study evaluates the impact of silica and nano-silica hydrogels on soil water retention, crop yield, and crop water productivity under variable irrigation regimes. Using a randomized complete block design with furrow irrigation, the experiment tested different hydrogel application rates and irrigation levels in rice (Oryza sativa L.) and clover (Trifolium alexandrinum L.) across two growing seasons. Statistical tests, including ANOVA and t-tests, confirm that nano-silica hydrogel significantly improves soil properties, yield, and crop water productivity (CWP), especially at moderate irrigation levels (70–90% of water requirements). In the first season, nano-silica hydrogel enhanced rice yield, with a maximum yield of 10.76 tons ha⁻¹ with 90% irrigation and 119 kg ha⁻¹ of hydrogel compared with other treatments. In the second season, clover yields were also positively affected, with the highest fresh forage yield of 5.02 tons ha⁻¹ with 90% irrigation and 119 kg ha⁻¹ nano-silica hydrogel. Despite seasonal variation, nano-silica hydrogel consistently outperformed silica hydrogel in terms of improving soil water retention, reducing bulk density, and enhancing hydraulic conductivity across different irrigation levels. Principal Component Analysis (PCA) revealed that nano-silica hydrogel significantly improved soil water retention properties, including the water-holding capacity (WHC), field capacity (FC), and available water (AW), and reduced the wilting point (WP). These improvements, in turn, led to increased crop yield and water productivity, particularly at moderate irrigation levels (70–90% of the crop’s total water requirements. These findings highlight the potential of nano-silica hydrogel as an effective amendment for improving soil water retention, enhancing crop productivity, and increasing crop water productivity under reduced irrigation conditions. Full article

Chile holds ~50% of temperate forests in the Southern Hemisphere, thus constituting a genetic–ecological heritage. However, intense anthropogenic pressures have been inducing distinct forest structural-regeneration patterns. Accordingly, we evaluated 22 soil properties at 0–5 and 5–20 cm depths in two protected sites, with similar perturbation records but contrasting post-disturbance regeneration stages: long-term secondary forest (~50 y) (SEC_FORST) (dominated by Chusquea sp.-understory) and a short-term forest after disturbance (~5 y) (FAD_IST) within a Nothofagus spp. forest to determine the potential of these soils to promote nutrient availability, water cycling, soil organic carbon (SOC) sequestration (CO₂→SOC), and microbiome. Results detected 93 correlations (r ≥ 0.80); however, no significant differences (p < 0.05) in physical or chemical properties, except for infiltration velocity (+27.97%), penetration resistance (−23%), SOC (+5.64%), and % Al saturation (+5.64%) relative to SEC_FORST, and a consistent trend of suitable values 0–5 > 5–20 cm were estimated. The SOC→CO₂ capacity reached 4.2 ± 0.5 (FAD_IST) and 2.7 ± 0.2 Mg C y⁻¹ (SEC_FORST) and only microbial abundance shifts were observed. These findings provide relevant insights on belowground resilience, evidenced by similar ecosystem services provision capacities over time, which may be influenced progressively by opportunistic Chusquea sp. Full article

The common bean (Phaseolus vulgaris L.) is a global staple, but to guarantee its provision, the crop water supply must be adequate, and bioinput application can benefit plants under drought. The objective was to evaluate the common bean’s response to bioinput application when it was cropped in soils with different water holding capacities submitted to a drought period. The greenhouse experiment used sandy loam and clayey soils. Seeds were sown, and 10 days after emergence (DAE), the treatments were applied: (i) no bioinput application or (ii) bioinput application (Priestia aryabhattai, re-applied at 46 DAE). The first plant growth evaluation was performed at 40 DAE. The irrigation maintained the crops’ needs until the beginning of flowering for all the treatments, when the irrigation was differentiated (for 10 days): (i) maintenance of irrigation or (ii) a drought period. A biochemical analysis was performed of superoxide dismutase activity [SOD], hydrogen peroxide [H₂O₂], peroxidase activity [POD], and malonaldehyde [MDA] production at 52 DAE. At 57 DAE, the second plant growth evaluation was performed, and the irrigation differentiation ended. Grain harvest followed physiological maturation. Priestia aryabhattai mitigated the drought stress in the common bean cropped in sandy soil by reducing the SOD, H₂O₂, and MDA production in comparison to no bioinput application. When it was cultivated in the clayey soil, the water availability was maintained for longer, reducing the plant’s dependency on bacteria for stress mitigation. Full article