Search Results (181)

Vast areas of natural rangelands in the Kingdom of Saudi Arabia (KSA) suffer from deterioration due to the scarcity of vegetation cover and poor soil quality. Assessing soil quality in rangelands is crucial to identifying degraded lands and to implementing proper sustainable management practices. In this study, a total data set (TDS) containing 27 physical and chemical soil indicators was generated for three rangelands (Al-Fahyhyl, Al-Sahwa, and Al-Tamryate) in KSA. Principal component analysis (PCA) and analytic hierarchy process (AHP) analysis were employed to establish a minimum data set (MDS) and to evaluate key physical and chemical properties affecting soil quality, along with the associated weight factor for each indicator. Results indicated that the MDS represented ≥70% of the total variability of the TDS and accurately estimated the soil quality index (SQI) based on determined physical and chemical soil properties in the study regions. Linear regression indicated high correlation between SQI-TDS and SQI-MDS, with the R² ranging between 0.51–0.87. On the surface layer (0–30 cm), the MDS contained seven soil indicators (sand, dispersion ratio (DR), mean weight diameter (MWD), bulk density (BD), total organic carbon (TOC), available phosphorus (Pa), and available potassium (Ka)), whereas in the sub-surface layer it contained six indicators (sand, DR, MWD, BD, TOC, Pa, and Ka). In all regions, sand had the largest weight factor (0.4514–0.4835), followed by TOC (0.2441–0.2512). Under the arid climate present in all the study sites, sand and TOC levels are crucial for nutrient retention, soil structure, and water retention. Most of the study areas had very low and low SQI (Al-Fahyhyl, 74.4%; Al-Sahwa, 61.8%; and Al-Tamryate, 81.7%), indicating an immediate need for suitable agricultural practices such as reduced tillage, increased organic amendments, and proper water management. The outcomes of this study offer valuable insights for land managers, legislators, and agricultural stakeholders to pinpoint regions in need of development, conduct comprehensive and continuous monitoring of SQI in rangeland areas, and implement land management plans for rangeland rehabilitation and environmental sustainability. Full article

Cover crop management in vineyards under a semiarid Mediterranean environment needs strategies that enhance soil C and N status and microbial functioning without increasing disturbance. This study compared cover crops biomass incorporation (harrowing, HR; rotary tillage; RT) and non-incorporation (NI, residues left on the topsoil) into the soil in a 12-year Grecanico dorato vineyard. Traditional vineyard soil management (continuously tilled for weeds control) was also used as a control. Soil samples from 0 to 20 and 20 to 40 cm were analyzed for total organic carbon (TOC), total nitrogen (TN), microbial biomass carbon (MBC) and nitrogen (MBN), and enzyme activities. NI and HR raised TOC and TN in the topsoil versus TR, with NI frequently maintaining advantages at depth. NI also maximized MBC/MBN and reduced the metabolic quotient (qCO₂), indicating improved microbial C-use efficiency; RT showed intermediate chemistry but depressed subsoil MBC and altered MBC/MBN. Enzyme profiles reflected contrasting mechanisms: RT boosted β-glucosidase in the topsoil, TR peaked for urease and arylsulfatase but alongside lower biomass and higher specific enzyme activities, while NI supported greater overall functioning via larger biomass and lower per-C enzyme demand. The calculated geometric mean enzyme (GMea) index emphasized transient TR flush versus steadier conservation functioning. Strong vertical stratification occurred for all indices, yet NI transmitted some benefits to 20–40 cm. We conclude that residue retention or moderate incorporation promotes larger, more efficient microbial population and more balanced nutrient cycling, whereas repeated rotary tillage risks subsoil inefficiencies. In semi-arid Mediterranean vineyards, low-disturbance cover-crop incorporation (HR) or, preferably, residue retention at the topsoil (NI) offer a simple, scalable route to sustain soil quality and long-term fertility. Full article

Soil erosion in vineyards is a major environmental problem, particularly in hilly Mediterranean environments. Our study evaluated the effectiveness of permanent grass cover (PG), continuous tillage (CT), and green manure (GM) in reducing soil erosion. Furthermore, a new software tool (ISUMmate_1.1.xlsm), based on the improved stock unearthing method (ISUM), was developed and tested to quantify soil mobilization between successive transects along vineyard inter-row. The field trial was carried out over a three-year period in a Tuscany (Italy) vineyard. The results showed that PG significantly improved aggregate stability and soil organic carbon (SOC) content, while exhibiting the lowest erosion rates. In contrast, GM showed the highest erosion rates as a result of soil disturbance associated with cultivation operations and the occurrence of unexpected intense rainfalls. ISUMmate_1.1 has proven to be a reliable tool for monitoring both water- and tillage-induced erosion, providing valuable information for sustainable vineyard management. Full article

Soil salinization poses a severe threat to agricultural sustainability in the Yellow River Delta, where conventional spectral indices are limited by vegetation interference and seasonal dynamics in coastal saline-alkali landscapes. To address this, we developed an inversion framework integrating spectral indices and vegetation temporal features, combining multi-temporal Sentinel-2 optical data (January 2024–March 2025), Sentinel-1 SAR data, and terrain covariates. The framework employs Savitzky–Golay (SG) filtering to extract vegetation temporal indices—including NDVI temporal extremum and principal component features, capturing salt stress response mechanisms beyond single-temporal spectral indices. Based on 119 field samples and Variable Importance in Projection (VIP) feature selection, three ensemble models (XGBoost, CatBoost, LightGBM) were constructed under two strategies: single spectral features versus fused spectral and vegetation temporal features. The key results demonstrate the following: (1) The LightGBM model with fused features achieved optimal validation accuracy (R² = 0.77, RMSE = 0.26 g/kg), outperforming single-feature models by 13% in R². (2) SHAP analysis identified vegetation-related factors as key predictors, revealing a negative correlation between peak biomass and salinity accumulation, and the summer crop growth process affects soil salinization in the following spring. (3) The fused strategy reduced overestimation in low-salinity zones, enhanced model robustness, and significantly improved spatial gradient continuity. This study confirms that vegetation phenological features effectively mitigate agricultural interference (e.g., tillage-induced signal noise) and achieve high-resolution salinity mapping in areas where traditional spectral indices fail. The multi-temporal integration framework provides a replicable methodology for monitoring coastal salinization under complex land cover conditions. Full article

Returning crop residues to soil is fundamental to sustainable agriculture, yet its adoption in cold-climate regions is hampered by an agronomic paradox: surface mulching conserves water but suppresses the spring soil temperatures required for crop establishment. In the present study, through a nine-year field experiment in a Mollisol under continuous maize cultivation, it was demonstrated that the method of maize straw incorporation, not merely its rate, is the decisive factor in resolving this conflict. While surface mulching maximized water conservation, it induced severe soil cooling and showed minimal gains in soil fertility. In contrast, incorporation via rotary tillage or deep plowing mitigated this cooling effect and proved superior for nutrient cycling. Among all strategies, rotary tillage of 50% residue (ROT-50) delivered the most balanced performance: it achieved the highest total nitrogen, substantially increased soil microbial biomass, and maintained one of the highest levels of Shannon diversity among incorporation treatments. These biogeochemical enhancements were driven by a fundamental, method-induced shift in the bacterial community from an oligotrophic to a copiotrophic structure. These findings shift the paradigm from a focus on residue quantity to one on incorporation method, providing a robust framework for reconciling crop productivity with long-term soil health in temperate agroecosystems. Full article

Introduced in the present study is a novel method for measuring soil density during standard tillage operations. The methodology involves the use of a strain gauge to measure the surface tensions of the plough body stem, reflecting the resistance force in the soil, through which the calculation of the density becomes feasible. The sensor is conveniently mounted above the contact area with the soil, allowing for easy replacement as required. Due to the small forces of surface deformation in the metal, a weight sensor with a capacity of 300 grams is used. The measurement process is continuous, and all plough bodies can be equipped with sensors. The results obtained demonstrate a high level of accuracy, with a Multiple R = 0.95 and R Square = 0.90 compared to tests conducted with a standard penetrometer, confirming the effectiveness and appropriateness of the proposed method. Full article

Conventional tillage and monocropping are common practices employed for cotton production in the Southern Great Plains (SGP) region, but they can be detrimental to soil health, crop yield, and water resources when improperly managed. Regenerative practices such as cover crops and conservation tillage have been suggested as an alternative. The proposed shift in management practices originates from the need to make agriculture resilient to extreme weather events including intense rainfall and drought. The objective of this study is to test the effects of these regenerative practices in an environment with limited rainfall. Runoff volume, nutrient and sediment concentrations and loadings, and surface soil moisture levels were compared on twelve half-acre (0.2 hectare) cotton plots that employed different cotton seeding rates and variable winter wheat cover crop presence. A winter cover implemented on plots with a high cotton seeding rate significantly reduced runoff when compared to other treatments (p = 0.032). Cover cropped treatments did not show significant effects on nutrient or sediment loadings, although slight reductions were observed in the concentrations and loadings of total Kjeldahl nitrogen, total phosphorus, total solids, and Escherichia coli. The limitations of this study included a short timeframe, mechanical failures, and drought. These factors potentially reduced the statistical differences in several findings. More efficient methods of crop production must continue to be developed for agriculture in the SGP to conserve soil and water resources, improve soil health and crop yields, and enhance resiliency to climate change. Full article

Urbanisation and land-use change are among the main pressures on soil health in periurban areas, but the multifunctionality of grassland soils is still not sufficiently recognised. In this study, the physical and chemical properties of soils under grassland, forest and croplands in the periurban area of Zagreb were investigated in a two-year period. Grasslands consistently exhibited multifunctional benefits, including high organic matter content (4.68% vs. 2.24% in cropland), improved bulk density (1.14 vs. 1.24 g cm⁻³) and an active carbon cycle indicated by increased CO₂ emissions (up to 1403 kg ha⁻¹ day⁻¹ in 2021). Forest soils showed the highest aggregate stability (91.4%) and infiltration (0.0006 cm s⁻¹), while croplands showed signs of structural degradation with the highest bulk density and lowest water retention (39.9%). Temporal variation showed that grassland was particularly responsive to favourable climatic conditions, with soil porosity and water content improving yearly. Principal component analysis showed that soil structure, biological activity and moisture regulation were linked, with grassland plots favourably positioned along the axes of resilience. The absence of tillage and the presence of permanent vegetation cover contributed to their high capacity for climate and water regulation and carbon sequestration. These results emphasise the importance of protecting and managing grasslands as an important component of urban green areas. Practices such as mulching, minimal disturbance and continuous cover can maximise the ecosystem services of grassland soils. In addition, the results highlight the potential risk of trace metal accumulation in cropland and grassland soils located near urban and farming infrastructure, underlining the need for regular monitoring in periurban environments. Integrating grassland functions into urban planning and policy is essential for improving the sustainability and resilience of periurban landscapes. Full article

Straw row grouping is vital in conservation tillage for precision seeding, and accurate centerline extraction of the seedling bands enhances agricultural spraying efficiency. However, the traditional single-threshold Otsu segmentation struggles with adaptability and accuracy under complex field conditions. To overcome these issues, this study proposes an adaptive multi-threshold Otsu algorithm optimized by a Simulated Annealing-Enhanced Differential Evolution–Whale Optimization Algorithm (SADE-WOA). The method avoids premature convergence and improves population diversity by embedding the crossover mechanism of Differential Evolution (DE) into the Whale Optimization Algorithm (WOA) and introducing a vector disturbance strategy. It adaptively selects thresholds based on straw-covered image features. Combined with least-squares fitting, it suppresses noise and improves centerline continuity. The experimental results show that SADE-WOA accurately separates soil regions while preserving straw texture, achieving higher between-class variance and significantly faster convergence than the other tested algorithms. It runs at just one-tenth of the time of the Grey Wolf Optimizer and one-ninth of that of DE and requires only one-sixth to one-seventh of the time needed by DE-GWO. During centerline fitting, the mean yaw angle error (MEA) ranged from 0.34° to 0.67°, remaining well within the 5° tolerance required for agricultural navigation. The root-mean-square error (RMSE) fell between 0.37° and 0.73°, while the mean relative error (MRE) stayed below 0.2%, effectively reducing the influence of noise and improving both accuracy and robustness. Full article

In Northeast China, due to long-term, high-intensity continuous cultivation of black soil, the practice of “overuse with insufficient nurturing” has led to severe degradation of the black soil. Straw return is a crucial strategy for enhancing soil organic matter (SOM). However, the mechanism of combing straw return with different tillage methods on black soil microbial community structure and soil organic carbon (SOC) fractions remains unclear. A field experiment was conducted in black soil using four tillage treatments: conventional tillage without straw return (CK), no tillage with straw incorporation (NTS), rotary tillage with straw incorporation (RTS), and deep tillage with straw incorporation (PTS). Corn yield and the contents and fractions of SOC were measured, whereas the microbial structure at different soil depths was assessed by high-throughput sequencing technology. Meanwhile, the correlations between microbial diversity, changes in SOC fractions, and corn yield were analyzed. As a result, the straw return treatments significantly increased the contents of SOC in the 0–20 cm soil layer (up to 19.82 g kg⁻¹ under RTS) and its labile fractions, enhanced soil microbial diversity (with a 7.03–25.14% increase in the Bacterial Chao1 index), and optimized the microbial community structure. Fungal diversity under PTS was the most prominent in the 20–40 cm depth. Correlation analysis indicated that the active SOC fractions and microbial diversity jointly explain the yield variation. The conclusions of this study will provide a theoretical foundation for developing scientifically sound straw return strategies in agricultural production. Full article

Maize (Zea mays) is one of the most cultivated crops in South Africa, serving as a staple food, stock feed, and a key element in several industrial applications. It contributes significantly to the growth of the South African agricultural economy. The cultivation of maize generates a large amount of agricultural waste, mainly in the form of maize stover (MS), which encapsulates leaves, stalks, cobs, and husks. Approximately 5.15 metric tons (Mt) yr⁻¹ of MS are generated in South Africa. This corresponds to an energy potential of 94 PJ. There is immense potential to surpass the annual yield of MS by 126% up to about 11.66 Mt yr⁻¹ through practices such as zero tillage and improved agricultural production systems. MS may pose a serious threat to the environment if not managed in a sustainable and eco-friendly manner. Valorization of MS into biogas presents an excellent opportunity to effectively control biomass waste while contributing to renewable energy production and mitigating dependence on depleting fossil fuels. However, MS continues to be overlooked as a sustainable bioenergy resource due to its lignocellulosic structure. This study explores the potential of converting MS into biogas for heat and power generation, addressing both energy needs and waste management in South Africa. The purpose is to provide knowledge that will inform researchers, innovators, industrialists, policy makers, investors, and other key stakeholders interested in renewable energy systems. Collaborative efforts among multiple stakeholders are vital to leverage biogas as a technology to promote socio-economic development in South Africa. Full article

Long-term no-till systems have led to shifts in weed communities and reduced the effectiveness of herbicide-based control. Occasional tillage is proposed as an alternative strategy to disrupt weed emergence patterns by redistributing seeds within the soil profile. This study aimed to evaluate the impact of occasional tillage on weed seedbank composition and vertical distribution of viable weed seeds and propagules within the soil profile, after more than 20 years of continuous no-till. A paired-plot experiment was conducted in Carlos Casares, Buenos Aires, Argentina, with three replications. Treatments included continuous no-till and occasional tillage (two disk harrow passes in August 2022 and April 2023) combined with three soil depths (0–5, 5–10, and 10–15 cm). Soil samples were collected in spring 2022 and fall 2023, and weed emergence was recorded under semi-controlled conditions. Overall species richness did not differ significantly between tillage treatments but was consistently greater in the upper 0–5 cm soil layer. Weed abundance also declined with depth. Five species, Chenopodium album, Stellaria media, Eleusine indica, Oxybasis macrosperma, and Heliotropium curassavicum, were frequent across treatments. Some species were exclusive to either no-till or tilled plots, for example, Datura ferox, Poa annua, and Veronica peregrina were found only in tilled plots, while Portulaca oleracea, Medicago lupulina, and Trifolium repens were exclusive to no-till plots. These results indicate that occasional tillage alters species composition and vertical seed distribution in the seedbank without significantly reducing total richness or abundance, offering an additional, but not always effective, tool to influence weed community structure in no-till systems. Full article

Crop rotation and simplified tillage affect soil properties and consequently crop yields. The use of heavy machinery in the tillage can affect soil degradation and reduce soil productivity. The aim of this study was to investigate the effect of soil packing and different soil tillage methods applied before the sowing of maize cultivated after grassland and in monoculture on soil compaction, soil organic carbon content, and maize yield. A strip–split–plot experiment was conducted on-farm in northeastern Poland from 2017 to 2021. The soil compaction was measured in the soil layers: 0–10, 10–20 and 20–30 cm in the leaf development stage (BBCH 19), the flowering stage (BBCH 67) and the maize kernel development stage (BBCH 79). The experimental factors were as follows: 1. preceding crop—grassland, maize; 2. degree of soil packing—without soil packing, soil packing after harvesting the preceding crop; 3. different soil tillage—conventional plough tillage method, reduced tillage method. Maize cultivation following a multi-species grassland resulted in a modest 1.47% increase in soil organic carbon content compared to continuous maize monoculture. In monoculture maize, all investigated reduced tillage methods led to increased soil compaction by 0.61–0.67 MPa. However, this adverse effect was mitigated by prior grassland cultivation. Maize grown after a multi-species grassland exhibited 14% higher silage mass yields. Considering the reduction in soil compaction and the enhanced yield potential, this preceding crop is recommended for maize cultivation. Although soil packing did not significantly impact maize yields, reduced tillage methods, such as subsoiling at 40 cm, medium ploughing at 20 cm, and passive tillage, led to a significant reduction in silage mass compared to other treatments. Full article

No-tillage (NT) is a key practice in conservation agriculture that minimizes soil disturbance, thereby enhancing soil structure, porosity, and overall quality. However, its long-term effects on soil pore networks and hydro-physical functions remain underexplored. This study evaluated the impacts of NT and conventional tillage (CT) on soil hydro-physical properties using undisturbed soil columns, X-ray computed tomography, and standard physical measurements. A field experiment was conducted under an eight-year continuous cropping system, with a four-year rotation [winter wheat (Triticum aestivum L.)—maize (Zea mays L.)—sunflower (Helianthus annuus L.)—peas (Pisum sativum L.)], comparing NT and CT treatments with three replications. Soil parameters including bulk density (BD), moisture content, total porosity (SP), water-stable aggregates (WSA), and saturated hydraulic conductivity (Ksat) were measured. Results showed that NT increased BD (1.45 g/cm³) compared to CT (1.19 g/cm³), likely due to reduced soil disturbance. Moisture content under NT was up to 78% higher than CT. Saturated hydraulic conductivity was also higher in NT, with 17% and 43% increases observed at harvest in 2022 and 2023, respectively, except in the 0–30 cm layer immediately after sowing. Micro-CT analysis revealed a 34–115% increase in macropores (>1025 μm) under NT at 10–40 cm depth. These findings demonstrate that long-term NT improves key soil hydro-physical properties, supporting its integration into sustainable farming systems to balance productivity and environmental stewardship. Full article

Long-term intensive agricultural management practices have led to a continuous decline in farmland soil quality, posing a serious threat to food security and agricultural sustainability. Green manure, as a natural, cost-effective, and environmentally friendly cover crop, plays a significant role in enhancing soil quality, ensuring food security, and promoting sustainable agricultural development. The improvement of soil quality by green manure is primarily manifested in the enhancement of soil physical, chemical, and biological properties. Specifically, it increases soil organic matter content, optimizes soil structure, enhances nutrient cycling, and improves microbial community composition and metabolic activity. The integration of green manure with agronomic practices such as intercropping, crop rotation, conservation tillage, reduced fertilizer application, and organic material incorporation demonstrates its potential in addressing agricultural development challenges, particularly through its contributions to soil quality improvement, crop yield stabilization, water and nutrient use efficiency enhancement, fertilizer input reduction, and agricultural greenhouse gas emission mitigation. However, despite substantial evidence from both research and practical applications confirming the benefits of green manure, its large-scale adoption faces numerous challenges, including regional variability in application effectiveness, low farmer acceptance, and insufficient extension technologies. Future research should further clarify the synergistic mechanism between green manure and agronomic measures such as intercropping, crop rotation, conservation tillage, reduced fertilization and organic material return to field. This will help explore the role of green manure in addressing the challenges of soil degradation, climate change and food security, develop green manure varieties adapted to different ecological conditions, and optimize green manure planting and management technologies. Governments should comprehensively promote the implementation of green manure technologies through economic incentives, technology extension, and educational training programs. The integration of scientific research, policy support, and technological innovation is expected to establish green manure as a crucial driving force for facilitating the global transition towards sustainable agriculture. Full article