Biochar is widely used to improve crop productivity and soil health; however, its adoption remains limited due to insufficient quantification of benefits and unclear mechanisms, particularly within regenerative organic systems. We conducted a pot experiment applying biochar at 0 (control), 11.2, and 22.4 Mg ha⁻¹ to sandy loam and loam soils planted with sweet pepper (Capsicum annuum L.) and measured plant performance, microbial biomass, and soil organic carbon (SOC). Yield was higher in sandy loam than loam (282 vs. 146 g plant⁻¹). Biochar increased loam yield from < 100 g plant⁻¹ (control) to 240 g plant⁻¹ at 22.4 Mg ha⁻¹, while sandy loam yield plateaued beyond 11.2 Mg ha⁻¹. Microbial biomass was greater in sandy loam (6845 ng g⁻¹) than loam (3737 ng g⁻¹) and declined 17

Tillage and cover cropping influence N, crop yield, quality, and soil properties in organic systems. This study evaluated four N application rates (0, 50, 100, and 150 kg ha- 1) in two industrial hemp (Cannabis sativa L.) types (grain and fiber) under conventional till (CT) and no-till (NT), with and without a legume cover crop (CC), in rotation with malt barley (Hordeum vulgare L.) from 2021 to 2024. Measurements included hemp biomass, grain and fiber yield, barley yield and grain quality, soil health indicators, and N use efficiency. Tillage was instrumental to hemp establishment, as NT with cover crop residue (NTCC) resulted in severe stand loss, preventing yield gains despite modest improvements in soil health indicators such as permanganate oxidizable carbon (POXC) and soil protein (typically 10-30 mg kg- 1). Because all CCs were established under full tillage, CC biomass could not be compared across tillage systems. Under CT, CCs enhanced hemp biomass and grain yield, and N fertilization up to 100 kg ha- 1 improved performance, whereas higher N provided no additional benefit. Barley crude protein and germination were unaffected by CC or N rate, although barley grain yield increased where hemp followed CC or higher N input, reflecting residual N rather than changes in soil C. No statistically significant differences in N use efficiency indices were detected among N rates. Soil health gains under NT did not translate into agronomic viability for hemp. Cover cropping and tillage should be integrated to optimize N use, productivity, and crop quality in organic hemp-barley systems.

Intensification of US livestock production, generating an estimated 1.27 billion metric tons of manure per year from nearly 10 billion animals, presents both a nutrient resource and an environmental challenge. This technical review synthesizes current knowledge on manure's agronomic and soil health benefits versus its environmental risks. The study compares different management approaches, land application, stockpiling, lagoons, and critically assesses advanced treatment and valorization technologies, including anaerobic digestion, solid-liquid separation, nutrient recovery (struvite precipitation, ammonia stripping), biochar co-composting, and precision application tools (injection, variable-rate spreading, and real-time nutrient sensors). Adoption drivers such as regulatory frameworks (Clean Water Act, concentrated animal feeding operation permits, and California SB 1383), economic incentives (Environmental Quality Incentives Program [EQIP] cost-share and carbon and nutrient credit markets), and digital innovations are also evaluated alongside persistent barriers of high capital costs, logistical constraints in nutrient transport, knowledge gaps in emission quantification (CH4, N2O, and NH3), pathogen fate, and site-specific trade-offs among air, water, and soil quality. The review also outlines potential future scenarios, from incremental technology mainstreaming to integrated circular biorefineries, and highlights research priorities to optimize manure as a circular resource while safeguarding ecosystem and human health. By contextualizing manure management within a climate-resilient, circular agricultural economy, this review identifies the research gaps and informs researchers, extension agents, and policymakers on strategies to advance sustainable livestock systems in the United States and beyond.

Industrial hemp (Cannabis sativa L.) is an emerging crop for renewable fiber materials. For farmers, finding a balance between agronomic performance and economic return is crucial, especially when targeting specific markets like the textile industry, which values not just fiber quantity, but overall quality. This field study, conducted at the Rodale Institute in Kutztown, Pennsylvania, assessed the effects of tillage (till vs. no till), cover crop (with cover vs. no cover), and nitrogen (N) rate (0, 50, 100, 150 kg ha-1) on hemp fiber yield, N concentrations in leaf and stalk, and mechanical performance under regenerative organic conditions. Fiber mechanical properties, including maximum load, tenacity, work of rupture, and modulus of elasticity were analyzed at Thomas Jefferson University. Results showed that biomass yield increased with N input, peaking at 9.2 Mg ha-1 under till systems with cover crop at 150 kg N ha-1 . However, fiber quality declined at higher N rates. The highest fiber quality metrics, including tenacity (610.5 MPa), modulus of elasticity (3.5 GPa), and work of rupture (31.4 newton mm-2) was achieved in no till system with cover crops and no N addition. A clear trade-off emerged: high N increased biomass yield but compromised fiber quality, while moderate input levels (e.g., till system with cover crop at 50 kg N ha-1) offered a balanced outcome. This suggests that regenerative practices not only support soil health but also improve fiber strength and flexibility. Farmers can tailor input strategies to match end-use goals: low-input systems for premium textile fibers and moderate inputs for bio-composite applications, supporting both ecologically sound and market demands.

Lettuce (Lactuca sativa L.) is a widely cultivated crop due to its short production cycle and high market demand. However, powdery mildew (Golovinomyces cichoracearum) poses a significant threat, reducing yields by up to 30% in various lettuce cultivars. This greenhouse study, conducted at the Rodale Institute in Pennsylvania, evaluated the impacts of pre-transplant UV light exposure and post-planting application of an OMRI-certified fungicide, potassium bicarbonate (MilStop), on powdery mildew infestation, yield, and nutritional quality of lettuce. The treatment included three factors: (a) UV-B (280 to 315 nm) exposure: treated vs. non-treated, (b) UV-C (100 to 280 nm) exposure: treated vs. non-treated, and (c) fungicide application: treated vs. non-treated, arranged in a factorial randomized complete block design with four replications. Lettuce seedlings (Salanova cultivar) were exposed to UV light before transplanting and later treated with MilStop. The results indicated that the combination of UV-B and MilStop significantly reduced powdery mildew infestation, while UV-C alone showed no significant effect. MilStop application enhanced lettuce yield, with treated plots showing a 44.8% increase in harvestable weight over control plots. While mineral and monosaccharide content were unaffected, UV-B exposure significantly increased total amino acid concentrations, including essential and non-essential amino acids. Pearson’s correlation analysis revealed a strong negative relationship between powdery mildew severity and harvestable weight, highlighting the importance of disease management. These findings highlight the potential of integrating UV light treatments and fungicide applications as effective, sustainable strategies for managing powdery mildew, improving lettuce yield, and maintaining nutritional quality in regenerative organic systems.

Soil nitrogen (N) is a crucial nutrient for agricultural productivity and ecosystem health. The accurate and timely assessment of total soil N is essential for evaluating soil health. This study aimed to determine the impact of bootstrapping techniques on improving the predictive accuracy of indirect total soil N in conventional wheat fields in Al-Muthanna, Iraq. We integrated a novel methodological framework that integrated bootstrapped and non-bootstrapped total soil N data from 110 soil samples along with Landsat 9 imagery on the Google Earth Engine (GEE) platform. The performance of the proposed bootstrapping-enhanced random forest (RF) model was compared to standard RF models for soil N prediction, and outlier samples were analyzed to assess the impact of soil conditions on model performance. Principal components analysis (PCA) identified the key spectral reflectance properties that contribute to the variation in soil N. The PCA results highlighted NIR (band 5) and SWIR2 (band 7) as the primary contributors, explaining over 91.3% of the variation in soil N within the study area. Among the developed models, the log (B5/B7) model performed best in capturing soil N (R2 = 0.773), followed by the ratio (B5/B7) model (R2 = 0.489), while the inverse log transformation (1/log (B5/B7), R2 = 0.191) exhibited the lowest performance. Bootstrapped RF models surpassed non-bootstrapped random forest models, demonstrating enhanced predictive capability for soil N. This study established an efficient framework for improving predictive capacity in areas characterized by limited, low-quality, and incomplete spatial data, offering valuable insights for sustainable nitrogen management in arid regions dominated by monoculture systems.

Saffron (Crocus sativus L.) is a perennial, stem-less, fall-blooming geophyte in the Iridaceae family. Nicknamed “red gold”, saffron is consistently one of the most expensive spices by weight on the global market. Propagating exclusively through corms, its flowering occurs from mid-October to late November in the Northern Hemisphere, displaying violet-colored petals with dark red to reddish-brown stigmas and yellowish brown to yellowish orange styles. Saffron thrives in loose, well-drained, low-density, clay-calcareous soils with adequate organic matter. The major phytochemical components contributing to the distinctive color, taste, and aroma of the stigmas are crocin, picrocrocin, and safranal, respectively. There has been a recent surge in scientific interest in saffron, driven by its potential therapeutic applications against cancer cells, Alzheimer's disease, and cardiovascular disorders. Saffron cultivation does not require significant land or equipment investment, provides employment opportunities, and can serve as an additional income stream for small farms. However, global saffron cultivation is challenged by climate change, rising labor costs, global supply chain disruptions, and product adulteration, emphasizing the need for multi-disciplinary research to understand and maximize the potential of saffron production. Further research into mechanization, biotechnology, and the development and enforcement of authenticity and quality standards will be critical to maintain a sustainable global supply. This review synthesizes current knowledge on saffron, with a focus on its potential in the US and other emerging production regions. It addresses saffron's origin, biology, chemical composition, uses, and market adulteration, while identifying key research gaps and opportunities for expansion. Emphasis is placed on agronomic practices and climate-resilient farming to support informed decision-making and the sustainable development of the saffron industry.

Climate change, driven by rising atmospheric concentrations of greenhouse gases (GHGs) such as CO2, poses the most pressing environmental challenges today. Soil carbon (C) sequestration emerges as a crucial strategy to mitigate this issue by capturing atmospheric CO2 and storing it in soil organic carbon (SOC), thereby reducing GHG levels and enhancing soil health. Although soil is the largest terrestrial C sink, capable of storing between 1500–2400 petagrams (Pg) of C, the practical potential for SOC sequestration through regenerative practices is still widely debated. This review examines the biotic, abiotic, structural, physical, and chemical limitations that constrain soil C sequestration, along with the human dimensions that influence these processes. It explores the role of plant physiology, root architecture, microbial interactions, and environmental factors in determining the efficacy of SOC sequestration. Furthermore, it discusses the potential innovative strategies, including photosynthetic modifications, root system engineering, microbial bioengineering, and the application of advanced materials such as C-capturing minerals, poly-carboxylic compounds, and nanomaterials, to enhance C capture and storage in soils. By providing a comprehensive understanding of these factors, this review aims to inform future research and policy development, offering pathways to optimize soil C sequestration as a viable tool for climate change mitigation.

Limited phosphorus (P) availability and declining soil biological health are major constraints in intensive rice (Oryza sativa L.)—wheat (Triticum aestivum L.) systems. Rock phosphate–enriched compost (REC), combined with microbial inoculants, offers a sustainable strategy for improving soil biological functioning. A field experiment was conducted under a randomized block design with seven treatments involving different combinations of REC, chemical fertilizers, phosphate-solubilizing bacteria (PSB), and arbuscular mycorrhizal fungi (AMF). Post-harvest soil samples from rice and wheat were analyzed for microbial biomass carbon (MBC), microbial biomass phosphorus (MBP), enzymatic activities, microbial populations, root colonization, yield, and P uptake. The combined application of REC with PSB and AMF significantly enhanced soil biological parameters compared with recommended fertilizer doses. Under the REC + PSB + AMF treatment, dehydrogenase, acid phosphatase, and alkaline phosphatase activities increased by 77.4%, 24.8%, and 18.1%, respectively, while MBC and MBP improved by 51.6% and 106.6%. Bacteria, fungi, and actinomycete population increased by 55.0%, 76.7%, and 82.8%, respectively, as well as mycorrhizal root colonization increased by 18.7%. Grain yield of rice and wheat increased by 16% and 6%, respectively, along with higher P uptake. The integrated use of REC with PSB and AMF improved soil enzymatic activity, microbial biomass, and nutrient acquisition, leading to higher crop productivity. These results indicate that REC combined with PSB and AMF is an effective nutrient management strategy for improving soil biological health, P utilization, and crop productivity in rice–wheat systems.

AbstractIndustrial hemp (Cannabis sativa L.), displaying more than 25,000 products, has been grown in North America since the 16th century. However, knowledge gaps persist in optimizing agronomic practices, including precision nitrogen (N) management, which is crucial for yield and phytochemical quality, for example, delta‐9‐tetrahydrocannabinol (THC) and cannabidiol (CBD). Addressing these gaps, a 2‐year field trial (2022 and 2023) was conducted at the Rodale Institute‐Pocono Organic Center in Blakeslee, PA, aiming to optimize CBD hemp production through precision N management. Forty experimental plots were established, with each assessing two main factors: (i) N rate: 0, 56, 112, 168, and 224 kg N ha−1 using an OMRI‐listed fertilizer, blood meal (12% N) and (ii) application method: banding and broadcasting. The 3‐week‐old hemp seedlings were transplanted into main plots, followed by fertilizer application and drip irrigation. Parameters including plant height, bud weight, biomass, and CBD yield were assessed, alongside CBD and THC concentrations in floral components and N concentration in leaves and flowers. There was a significant interaction of N rate and application method, impacting biomass yield, while the N rate also influenced CBD concentration. Blood meal supplied at 224 kg N ha−1 yielded the highest biomass and elevated CBD and THC concentrations; however, this did not differ significantly from 168 kg N ha−1 application. Therefore, the recommended optimal N fertilizer rate for Northeastern CBD hemp production is 168 kg N ha−1, with an upper limit of 224 kg N ha−1. Furthermore, the banding method of fertilizer application was more effective than broadcasting.

Industrial hemp ( Cannabis sativa L.) is a versatile crop with applications in fiber, seeds, and medicine. Recent legalization has renewed interest in industrial hemp in the United States, particularly in fiber production, which has a critical role in carbon (C) sequestration and various industries, including textiles and construction. A 2‐year field experiment (2022–2023) was conducted at Rodale Institute—Pocono Organic Center, Blakeslee, PA, evaluating the performance of four hemp varieties (MS 77, Futura 75, Santhica 27, and Han NE) under regenerative organic systems. Seed rates were considered as 73 kg ha −1 for Santhica 27 and Futura 75, 135 kg ha −1 for MS 77, and 270 kg ha −1 for Han NE, targeting a plant population of 2.47 million plant ha −1 across varieties. Data on canopy cover, plant height, yields (biomass, stem, leaf, and flower), and cannabinoids were collected to assess the effects of variety and environmental conditions on growth and yield. Root samples from 2023 were also analyzed for arbuscular mycorrhizal fungi (AMF) colonization. Han NE demonstrated the highest growth, yields, and canopy cover, followed by MS 77, with more favorable growing conditions in 2023. Additionally, AMF colonization was consistent across varieties, reporting a higher colonization in MS 77 (45.37%), suggesting enhanced nutrient uptake and stress tolerance. Based on the results, Han NE and MS 77 are promising hemp varieties for fiber production in this region. Further research is required to explore the impact of mycorrhizal colonization on hemp production under varying nutrient conditions for sustainable production.

Industrial hemp ( Cannabis sativa L.) production is expanding in the United States, generating sustained interest in this multipurpose crop, though the optimal agronomic conditions (e.g., row spacing, planting density, and nutrient management) for maximizing fiber yield remain unclear in many regions. Key factors like row spacing not only affect resource utilization but also play a crucial role in weed suppression, especially in regenerative organic systems. This research at the Rodale Institute, Kutztown, PA, examined the effects of row spacing (19 cm narrow vs. 38 cm wide) and fertilization treatments (control, blood meal containing 12% N at 112 kg ha −1 and 224 kg ha −1 , and compost at 60 t ha −1 ) on yield and chemical composition of industrial hemp seed (cultivar: Canda) over two growing seasons (2019 and 2020). The narrow row spacing increased plant and stalk density, boosting bast fiber yield, while wider spacing promoted weed biomass due to reduced crop competition. Higher temperatures in the late growing season in 2020 led to 3.5 times increase in biomass yield and improved grain protein content. Principal component analysis indicated that compost influenced nutrient availability and heavy metal uptake more strongly than row spacing or blood meal treatments. Blood meal had limited effects, likely due to insufficient application rates, but showed promise for minimizing heavy metal uptake compared to compost. Optimal crop performance depends on the interaction between climatic conditions and agronomic practices. Selecting appropriate row spacing and nutrient sources is essential for enhancing hemp production while reducing input costs and minimizing environmental impact.

Soil nitrous oxide (N2O) emissions exhibit high variability in intensively managed cropping systems, which challenges our ability to understand their complex interactions with controlling factors. We leveraged 17 years (2003-2019) of measurements at the Kellogg Biological Station Long-Term Ecological Research (LTER)/Long-Term Agroecosystem Research (LTAR) site to better understand the controls of N2O emissions in four corn-soybean-winter wheat rotations employing conventional, no-till, reduced input, and biologically based/organic inputs. We used a random forest machine learning model to predict daily N2O fluxes, trained separately for each system with 70% of observations, using variables such as crop species, daily air temperature, cumulative 2-day precipitation, water-filled pore space, and soil nitrate and ammonium concentrations. The model explained 29%-42% of daily N2O flux variability in the test data, with greater predictability for the corn phase in each system. The long-term rotations showed different controlling factors and threshold conditions influencing N2O emissions. In the conventional system, the model identified ammonium (>15 kg N ha-1) and daily air temperature (>23°C) as the most influential variables; in the no-till system, climate variables such as precipitation and air temperature were important variables. In low-input and organic systems, where red clover (Trifolium repens L.; before corn) and cereal rye (Secale cereale L.; before soybean) cover crops were integrated, nitrate was the predominant predictor of N2O emissions, followed by precipitation and air temperature. In low-input and biologically based systems, red clover residues increased soil nitrogen availability to influence N2O emissions. Long-term data facilitated machine learning for predicting N2O emissions in response to differential controls and threshold responses to management, environmental, and biogeochemical drivers.

In recent years, the soil has garnered significant attention for conservation, food security, and ecosystem services. Soil health has declined over the years compared to native states due to the intensive agricultural production system. Scientific communities and producers have significantly considered soil health improvement by incorporating different sustainable and regenerative agricultural practices. Evaluation of improvements in soil health management requires up-to-date, high-quality, high-resolution, spatiotemporal, continuous soil and environmental data coupled with agronomic features. It is critical to obtain both temporally and spatially large-scale data for accurate and precise soil health assessments. However, current soil testing methods are expensive, time-consuming, and lack broad-scale spatiotemporal variables. Improvements in satellite-based remote sensing, cloud-based robust image processing software, statistical methods, and machine learning models have stimulated broad-scale resource assessment. Remote sensing has been successfully applied to measuring soil moisture, salinity, organic carbon, and evapotranspiration. Remote sensing can help develop rapid soil health assessments and mathematical models with spatial information on soil properties and management practices. This chapter will discuss remote monitoring technologies that substantially improve our ability to measure and manage soil health.

In this study, the complex interactions between soil types, compaction, and moisture on nitrogen (N) transformation processes such as ammonia (NH3) volatilization, ammonification, nitrification, and denitrification were examined over a 30-day period using a simulated column approach. Two soil types: loam, and sandy loam, were subjected to three compaction treatments—control, surface, and sub-surface compaction—and two moisture regimes, dry and wet. Liquid urea ammonium nitrate (32-0-0) was used as the N fertilizer source at a rate of 200 kg N ha-1. Key indicators of N transformations were measured, including residual concentrations of ammonium (NH4-N) and nitrate (NO3-N), NO3-N leaching, NH3 volatilization, and nitrous oxide (N2O) emissions. Findings revealed that compaction significantly increased residual NH4-N concentrations in deeper soil profiles, with the highest 190.80 mg kg-1 recorded in loam soil under sub-surface compaction and dry conditions. Nitrification rates decreased across both soil types due to compaction, evidenced by elevated residual NH4-N levels. Increased NO3-N leaching was observed in loam soil (178.06 mg L-1), greater than sandy loam (81.11 mg L-1), due to initial higher residual NO3- in loam soil. The interaction of compaction and moisture most affected N2O emissions, with the highest emissions in control treatments during dry weather at 2.88 kg ha -1. Additionally, higher NH3 volatilization was noted in moist sandy loam soil under control conditions at 19.64 kg ha -1. These results highlight the necessity of considering soil texture, moisture, and compaction in implementing sustainable N management strategies in agriculture and suggest recommendations such as avoiding broadcast application in moist sandy loam and loam soil to mitigate NH3 volatilization and enhance N use efficiency, as well as advocating for readjustment of fertilizer rate based on organic matter content to reduce potential NO3-N leaching and N2O emissions, particularly in loam soil.

Sustainable use of croplands is facing a challenge to maintain organic carbon (C) in soil. Pyrolyzed coal or coal char (CC) is a porous C material produced from the pyrolysis of coal containing high organic C, large surface area, and low bulk density like biochar (BC). This study evaluates corn (Zea mays L.) grain yield and selected soil properties in soil amended with CC and BC at two rates (22 and 44 Mg ha−1) with farmyard manure (FM) (66 Mg ha−1) and without FM addition. This field experiment was performed in sandy loam soil at the University of Wyoming’s Sustainable Agricultural Research and Extension Center (SAREC), Lingle, WY, USA. Two years of field study results indicated CC and BC applied at 22 Mg ha−1 with FM resulted in significantly greater average corn grain yields (13.04–13.57 Mg ha−1) compared to the no char’s treatment (11.42 Mg ha−1). Soil organic matter (SOM) content was significantly greater in the higher application rates of CC and BC than in treatments without chars. Overall, soil nitrate nitrogen (NO3-N), phosphorous (P), and potassium (K) were found significantly greater in CC and BC co-applied with FM treatments. Soil water-holding capacity (WHC) significantly improved in sandy loam soil (up to 27.6% more than the no-char treatment) at a greater concentration of char materials. This study suggests that char materials applied at a moderate rate (22 Mg ha−1) with FM can improve soil properties and crop yield.

Organic farming, which is deeply rooted in traditional agricultural practices, has witnessed a profound evolution over the last century. Transitioning from a grassroots initiative resisting the industrialization of agriculture to a global industry, organic farming now plays a pivotal role in addressing contemporary challenges related to environmental health, sustainability, and food safety. Despite the growing consumer demand for organic products and market access, organic farming has its challenges. This paper discusses the origin and evolution of organic farming with an emphasis on different types of organic fertilizers, benefits, and challenges. Nutrient variability and the slow-release nature of organic fertilizer often do not meet crop demands and can substantially reduce yield. Some organic fertilizers, like manure and biosolids, can provide a higher yield benefit, but there are environmental and health risks associated with them. Weed and pest management in organic farming can be labor-intensive and increase costs. Inefficient planning of organic farming and rapid transition can also create food insecurity. This paper also gives a brief account of the current certification process for organic fertilizers and their technicalities. It showcases how the holistic approach of organic farming extends beyond production, including strategies like reducing food waste and building self-sufficient farming communities. These practices contribute to a more sustainable agricultural system, reducing environmental impacts and supporting local economies. Future technological innovations, especially in precision agriculture and bio-physicochemical models, can help in formulating targeted organic fertilizers.

Abstract Soil profile distribution of soil organic carbon (SOC) in different soil types provides information about the carbon (C) dynamics in terrestrial ecosystems, and is also important for understanding climate feedback mechanisms and for developing a proper farm level SOC management decision. However, there are limited studies on it when we consider soil horizons of dominant soil orders of Nepal, which mostly use a fixed depth approach rather than horizon-based approach while studying profile SOC distribution. We collected soils from master horizons (0 to 100 cm) of three dominant soil orders (Alfisols, Entisols, and Inceptisols) in Chitwan district of Nepal, to understand the controlling factors of SOC accumulation. Dominant soil order regions were identified using a soil map prepared by the National Land Use Planning Project where a pit of 1 m3 was dug for each soil order and replicated four times. The highest SOC concentration (10.1 ± 0.6 g kg−1) was found in Alfisols followed by Entisols (8.8 ± 0.3 g kg−1) and Inceptisols (7.2 ± 8.9 g kg−1). Similarly, the highest SOC stock was found in the soil profile of Alfisols (200.01 ± 15.97 t ha−1) followed by Entisols (124.67 ± 12.20 t ha−1) and Inceptisols (113.27 ± 10.30 t ha−1) horizons. Surface (A) horizons of all three-soil order had significantly higher SOC than sub-surface (B and C) horizons. Regression analysis showed significant variability in SOC to clay content (R2 = 0.45, p < 0.0001), sand (R2 = 0.19, p < 0.001), and total nitrogen (N; R2 = 0.835, p < 0.001). Principal component analysis showed that the controlling edaphic factors differ with the soil types considering SOC change in the whole soil profile. Overall, we found that soil pH, N, clay and sand contents are the major controlling factors that drive the SOC accrual in dominant soil orders of Nepal. Graphical Abstract