Search Results (2,514)

Although adding phosphorus (P) and zinc (Zn) fertilizers to rhizobial inoculation improves nutrient accumulation in chickpeas, it is unclear which is most effective. This study evaluated whether inoculating chickpeas grown in silty-loam or silty-clay-loam soil with liquid- or peat-based rhizobial inoculants, in addition to P and/or Zn fertilizer, alters shoot nutrient concentration. The following genotypes were used: ICCV3110, ICCV8101, ICCV97024 and ICCV92944. The following levels of fertilizer were used: no addition of fertilizer, 10 kg/ha Zn, 40 kg/ha P, and Zn plus P. The following combinations of fertilizer and rhizobial inoculation were used: Zn plus P (peat-based inoculant), denoted as Zn + P + R_P, and Zn plus P (liquid-based inoculant), denoted as Zn + P + R_L. Our results showed that ICCV97024 exhibited increased shoot P, Ca, Mg, Fe and Zn concentrations when grown in silty-loam soil and increased shoot Ca, Zn, Mn and B concentrations when grown in silty-clay-loam soil. Adding P, or P plus Zn, increased shoot P, while adding Zn, or Zn plus P + R_L, enhanced shoot P, Fe and B. Adding Zn increased shoot Zn, K and Ca, and adding Zn plus P + RP increased shoot Ca. Overall, chickpeas grown in silty-loam soil accumulated the most nutrients. Adding P, P plus Zn and Zn + P + R_L improved shoot P, while adding Zn and Zn + P + R_P enhanced shoot Zn and Ca, respectively. Full article

A two-year field experiment was conducted to clarify the regulatory effects of nitrogen (N), phosphorus (P), and potassium (K) combined with drip fertigation on the yield, yield components, and grain quality of winter wheat in lime concretion black soil (Calcaric Cambisols). The objective was to screen a sustainable fertilization model for coordinating high yield and quality in the Huang-Huai-Hai Plain. An L₁₆(4³) orthogonal design was adopted to investigate yield, protein content, wet gluten, test weight (TW), and grain hardness. Range analysis and ANOVA were used to evaluate factor effects and interactions. The results showed that N was the dominant factor affecting yield and quality (Rank 1), followed by K (Rank 2), while P showed the weakest effect. Compared to the control (N0P0K0), the optimized N–P–K combination increased grain yield by an average of 315.0% and enhanced grain crude protein by 55.3% over the two seasons. The optimal combination for maximum yield was N170P30K120 (kg/ha), which optimized the source–sink relationship by balancing spike density and 1000-grain weight. High N (220 kg/ha) combined with low P and high K achieved the best nutritional quality. The 3D response surface analysis confirmed significant synergistic interactions between N–K and N–P in promoting grain filling and protein synthesis. Rational NPK drip fertigation, particularly when synchronized with critical growth stages (jointing and grain filling), can simultaneously enhance grain yield and quality in this soil type. The optimized combination provides theoretical support and a robust fertilization strategy for green and efficient wheat production in the region. Full article

This study evaluates nitrogen (N) and phosphorus (P) pollution in the Ankara River Sub-basin, Türkiye, using the grey water footprint (GWF) approach. A Tier-1 GWF approach was applied, complemented by a sensitivity analysis to assess the influence of key parameters, including leaching–runoff fractions and water quality thresholds. The results should be interpreted as indicative rather than absolute values, as they depend on assumptions related to leaching fractions and background concentrations. By integrating data from agricultural diffuse sources and municipal wastewater treatment plants (WWTPs), the research identifies critical pollution hotspots and sectoral pressures on water resources, causing water quality degradation. The results reveal that P is the primary limiting pollutant governing GWF magnitudes across the sub-basin. The total GWF was estimated at 8294 million m³ yr⁻¹ in the sub-basin outlet. Approximately 10% and 31% of the basin-wide GWF were associated with fertilizer-based diffuse sources and WWTP1, respectively. The study demonstrates that regulatory compliance alone does not guarantee the protection of a river’s assimilative capacity. These results provide a basis for policy development, emphasizing the need to move beyond concentration-based regulations toward management frameworks that explicitly consider assimilative capacity and cumulative basin-scale impacts. Full article

Monoculture plantations often face challenges of soil degradation and declining ecosystem services. Intercropping is beneficial to improving soil quality; however, the long-term effects of intercropping woody plants with medicinal herbs on soil ecosystems remain unclear. This study aimed to investigate the temporal effects of different durations of poplar intercropping with Aralia elata on soil physicochemical properties, enzyme activities, and soil microbial community structure. Soil samples were collected from the 0–20 cm soil layer, with composite samples obtained by mixing four soil cores per plot. We determined soil physicochemical properties, including pH, total carbon (TC), total nitrogen (TN), and total phosphorus (TP); soil enzyme activities, including invertase, urease, phosphatase, and β-N-acetylglucosaminidase (NAG); and soil microbial community structure using high-throughput sequencing of the bacterial 16S rRNA gene and fungal ITS region. Intercropping significantly affected soil chemical properties and enzyme activities in poplar plantations. Compared with the monoculture control (Y), TN (p < 0.01) and TC (p < 0.01) contents increased significantly in the 3- and 7-year intercropping treatments. The activity of β-N-acetylglucosaminidase (NAG) was enhanced following poplar–Aralia elata intercropping. In addition, intercropping significantly changed the composition and structure of soil microbial communities. In summary, introducing Aralia elata into poplar plantations can effectively improve soil fertility and reshape soil microbial community structure. This positive effect is time-dependent and becomes more significant with a 7-year intercropping duration. Poplar–Aralia elata intercropping represents a feasible management strategy to enhance ecological sustainability and soil health in plantation ecosystems of Northeast China. Full article

Rainfed wheat (Triticum aestivum L.) production in semi-arid regions is strongly influenced by precipitation variability, soil water availability, and crop management practices. This study evaluated the effects of nutrient management under uniform weed control on soil water dynamics, weed density, and grain yield of winter wheat grown under rainfed no-till conditions in southern Kazakhstan. Field experiments were conducted during the 2018–2021 growing seasons on gray soils characterized by low organic matter and limited nitrogen and phosphorus availability. Eight fertilization treatments, including phosphorus and nitrogen combinations and a micronutrient treatment, were arranged in a randomized complete block design. Soil moisture reserves, weed density, and grain yield were analyzed in relation to precipitation variability. Productive soil moisture reserves in the 0–100 cm layer at tillering (BBCH 21–25) ranged from 155 to 178.8 mm and were closely associated with overwinter precipitation. Balanced nitrogen–phosphorus fertilization reduced weed density from 38 plants m⁻² in the control to 16 plants m⁻² under the P₄₅N₇₀ treatment. Yield stability varied across dry, normal, and wet years, reflecting the influence of precipitation conditions on crop performance. Overall, the results suggest balanced fertilization in no-till systems contributes to improved resource use and more stable wheat production under variable precipitation. Full article

Returning spent mushroom substrate (SMS) to the field is an effective way to dispose of it. However, given the substantial nutrient consumption associated with Volvariella volvacea SMS, their effects on soil properties and crop performance warrant further investigation. By analyzing the effects of three different application rates of SMS on soil nutrients and lettuce (Lactuca sativa L.) quality, the results showed that the group with 1.5 kg m⁻² SMS addition improved the total nitrogen (+21.2%), and organic content (+27.9%) in soil, and it demonstrated particularly outstanding performance in enhancing the survival rate (+21.9%), average weight (+71.7%), chlorophyll content (+45.6%), and total phenolic content (+25.2%) of lettuce. By comparing the soil microbial communities in the control group, the SMS (1.5 kg m⁻²) treatment group, and the organic fertilizer treatment group, it was found that they were mainly composed of Group S1, S2, and S3 microorganisms, respectively. The microbial community evenness in the treatment groups was greater than that in the control group. Furthermore, the results also revealed that the microbial conversion efficiency of nitrogen and phosphorus in the SMS treatment group was higher than the control group, which promoted nutrient cycling and improved the quality of lettuce. Our analysis provides an environmentally friendly way for Volvariella volvacea SMS disposal. Full article

Integrating biochar with plant growth-promoting rhizobacteria (PGPR) is a promising strategy for sustainable soil management; however, the synergistic mechanisms governing rhizosphere microbial assembly remain inadequately understood. In this study, we investigated the combined effects of maize biochar (YM) and Bacillus amyloliquefaciens (BA) on tomato performance, soil physicochemical properties, and bacterial community dynamics via a controlled pot experiment. The results demonstrated that the synergistic treatment (YMBA) significantly enhanced tomato yield by 18.3% compared to the control, outperforming individual applications. This promotion was coupled with a comprehensive improvement in soil fertility, characterized by significant increases in soil organic matter (SOM), available nutrients (N, P, and K), and the activities of urease and acid phosphatase. High-throughput sequencing revealed that YMBA treatment significantly restructured the rhizosphere bacterial community, significantly increasing microbial richness and diversity. Notably, the synergistic application promoted the recruitment of beneficial taxa, particularly within the phylum Pseudomonadota. Mantel test analysis further elucidated that SOM and available phosphorus (AP) were the primary environmental drivers shaping the bacterial community turnover. Our findings suggest that biochar acts as a functional niche that facilitates B. amyloliquefaciens colonization and modulates the indigenous microbiota, providing a theoretical framework for utilizing cross-trophic synergies to optimize crop productivity and soil health. Full article

This study evaluated the use of visible and near-infrared (Vis-NIR) spectroscopy combined with machine learning (ML) algorithms to predict soil fertility-related properties in two contrasting agroecological regions of Peru: the Highlands and the Rainforest. A total of 297 soil samples were analyzed using portable spectroradiometers covering a spectral range of 350–2500 nm, applying transformations such as Savitzky–Golay smoothing, first derivative, and band depth. Predictive models were developed using PLSR, Random Forest, Support Vector Machines, and neural networks. Results show variable predictive performance across soil properties and ecosystems. Organic matter in Highland soils and calcium in Rainforest soils achieved the strongest test-set accuracy (R² > 0.70), while pH and texture fractions showed moderate performance (R² = 0.42–0.67), and mobile nutrients including phosphorus, potassium, and sodium showed limited predictive accuracy due to their weak spectral expression. Spectral predictions were further integrated into a structured nutrient balance framework to assess agronomic reliability. Nitrogen fertilizer recommendations showed the strongest agreement between observed and predicted values across both ecosystems, whereas K₂O and CaO recommendations in Highland soils were substantially underestimated, demonstrating that property-level statistical performance does not guarantee agronomic reliability. These findings confirm that Vis-NIR spectroscopy combined with ML represents a fast, cost-effective, and sustainable alternative to conventional soil analysis, especially in rural areas with limited laboratory infrastructure. Expanding regional calibration datasets and exploring mid-infrared FTIR spectroscopy as a complementary technology are identified as priority directions for improving predictions of agronomically critical nutrients. Full article

The severe continuous cropping obstacles in Morchella cultivation, driven primarily by soil microecological imbalance, critically constrain the sustainable development of the industry. To address this challenge, this study evaluated the efficacy of rotary tillage, calcium cyanamide (CaCN₂), and organic fertilizer, applied individually and in combination, in mitigating these obstacles and explored the underlying microbial mechanisms. The soil was treated on 5 August 2024, and soil samples were collected on 5 October 2024. Four treatments were established: continuous cropping control (CK), rotary tillage (XGX), rotary tillage combined with calcium cyanamide (MPD), and rotary tillage combined with calcium cyanamide and organic fertilizer (MPX). Soil chemical properties were analyzed in conjunction with metagenomic sequencing to characterize the responses of soil properties and microbial communities, including both eukaryotic and bacterial taxa. The results indicated that the MPD treatment showed a relatively pronounced effect in enhancing key soil fertility indicators, including soil organic matter (OM), total nitrogen (TN), available nitrogen (AN), available potassium (AK), and total phosphorus (TP). All amendments significantly altered microbial community structures. Specifically, the integrated MPX treatment effectively reduced the relative abundance of the pathogenic fungus Olpidium while maintaining higher overall microbial diversity. It also significantly promoted the abundance of Morchella itself and beneficial bacterial phyla such as Actinomycetota and Pseudomonadota. Redundancy analysis identified AN and AK as the primary drivers of eukaryotic community variation, whereas Availa-ble phosphorus (AP) and potential of hydrogen (pH) were the key factors shaping the bacterial community. The results indicated that MPD was the showed relatively pronounced effectiveness in rapidly improving soil fertility and suppressing pathogenic fungi. In contrast, MPX showed relatively better performance in optimizing microbial community structure, enhancing microbial diversity, and strengthening overall ecological stability. These two treatments exhibited distinct advantages in soil chemical improvement and microbial community regulation, respectively, thereby providing alternative practical strategies and a theoretical basis for the ecological management of continuous-cropping obstacles in Morchella cultivation. It should be noted that this study did not include treatments with calcium cyanamide alone, organic fertilizer alone, or their combined application without rotary tillage. This is primarily because rotary tillage is a standard land preparation practice in Morchella cultivation, and the use of soil amendments without accompanying tillage is rarely adopted under practical production conditions. Full article

Sandy calcareous soils in arid regions suffer from low phosphorus (P) availability due to high fixation rates, limiting crop productivity. This study investigates a novel hybrid smart fertilizer (BN) composed of olive pomace biochar (BC) and nano-hydroxyapatite (nHAP). BN was synthesized and characterized using XRD, FTIR, SEM/TEM, and zeta potential analysis. Its P release kinetics were modeled, and its agronomic performance was assessed on faba bean (Vicia faba L.) in a pot experiment under sandy soil conditions with and without wood vinegar (WV). The 1:1 BC:nHAP formulation showed a two-stage release profile: a rapid initial burst (Higuchi model, R² = 0.86) followed by sustained zero-order release (R² = 0.80). In the pot experiment, BN combined with WV significantly increased plant height by 36%, shoot fresh weight by 232%, and available soil P by 39% compared to conventional SSP (p < 0.05). This synergistic treatment also improved root nodulation and nutrient (N, P, K) uptake. The BC-nHAP hybrid coupled with WV acts as an efficient P delivery system, improving soil fertility in arid environments based on circular economy principles, aligning with SDGs 2, 12, and 15. Full article

Efficient soil fertility monitoring is essential for sustainable agriculture, food security, and environmental management across Africa, yet conventional laboratory methods remain prohibitively costly and slow for continental-scale applications. Soil spectroscopy is considered as a rapid, non-destructive alternative with transformative potential. This review provides a systematic synthesis of spectroscopic applications across Africa, encompassing laboratory, field, airborne, and satellite-based platforms, while examining major data sources including the Africa Soil Information Service (AfSIS) and GEO-CRADLE spectral libraries. We critically evaluate the evolution of modeling approaches, revealing that Partial Least Squares Regression (PLSR) dominates, but a shift toward advanced frameworks like hybrid physically based models, ensemble learning and deep neural networks is essential. Critically, we identify a pronounced imbalance wherein laboratory spectroscopy prevails while imaging and satellite-based approaches remain comparatively underutilized, despite their unparalleled potential for scaling point measurements to continental extents. The review consolidates findings on key soil properties, demonstrating consistent successes for primary constituents with direct spectral responses (i.e., organic carbon), while revealing relative uncertainty for properties inferred indirectly via covariance (e.g., available phosphorus, potassium). Despite significant local and regional progress, the absence of a standardized pan-African spectral library and the intractable transferability problem remain formidable barriers. Future research must pivot decisively toward imaging spectroscopy and satellite platforms, mitigating PLSR dominance through systematic adoption of ensemble methods, transfer learning, and model harmonization frameworks to fully operationalize these technologies in support of Africa’s sustainable development goals. Full article

Availability of phosphorus (P) is thought to limit bole growth in wet tropical forests, raising concern that removing P through repeated logging in P-limited stands may be unsustainable. Motivated by a study in Indonesia, we analyzed Olsen extractable and total soil P in the upper 10 cm in paired samples we collected under vs. near decaying boles of two contrasting species in a wet tropical forest in Puerto Rico. Guarea guidonia had higher wood and leaf P concentrations than Dacryodes excelsa. G. guidonia colonized valleys with higher soil P concentrations than ridge sites dominated by D. excelsa. We used two age cohorts of trees > 30 cm diameter, felled by hurricanes Hugo in 1989 (11 years old) and Georges in 1998 (1.5 years old), but soil P did not differ with age. Soil Olsen P concentrations were significantly higher under versus away from boles of both species. Paradoxically, augmentation of soil P was greater under boles of D. excelsa than G. guidonia despite having lower wood P. Soil % C and Olsen P were strongly positively correlated in D. excelsa but not in G. guidonia, suggesting that regulation of soil P-availability differs between ridges and valleys. Both soil C and P may be critical for maintaining soil fertility on ridges in a wet tropical forest. Our results are discussed in the context of prior experiments at our site, including two where bole growth increased with wood addition and/or decreased after removal of woody debris. These studies in Puerto Rico, together with others elsewhere, suggest that reduced forest productivity could potentially result from repeated logging of forest stands on ridges with low P-availability in humid tropical areas since decaying wood could directly and indirectly maintain P-availability in sites with low soil P-availability. We suggest several hypotheses on P-cycling in montane humid tropical forests that need further research to elucidate mechanisms controlling soil P-availability and identify sites where repeated logging is likely to be unsustainable. Full article

Climate change-induced variability in temperature and precipitation increasingly constrains crop production on sandy-textured soils with low water-holding capacity and limited nutrient retention. Such soils, classified as Brunic Arenosols, are widespread across the temperate climate zone of Central Europe, particularly in post-glacial landscapes, where they constitute a significant proportion of marginal agricultural lands. This study evaluated the relative influence of growing-season weather conditions and selected soil physicochemical properties on the yield of Camelina sativa and Brassica carinata cultivated under low-input management on Brunic Arenosols in northwestern Poland during the 2023 season. Yields varied markedly among sites. Camelina sativa produced yields from 300 to 930 kg ha⁻¹, with the highest yield recorded at the site characterized by higher BS and phosphorus availability. Brassica carinata produced yields from 0 to 370 kg ha⁻¹, including complete yield loss at one location due to severe pathogen infestation. Spearman’s correlation analysis revealed that temperature was a key determinant for both crops (r = 0.77 for C. sativa; r = 0.82 for B. carinata). For Camelina sativa, yield was strongly associated with BS (r = 0.80) and available P (r = 0.69), whereas Brassica carinata was more sensitive to climatic variability, showing a negative relationship with precipitation (r = −0.63). The results indicate species-specific responses to soil fertility and weather conditions under water- and nutrient-limited conditions typical of Central European sandy soils. While Camelina sativa performance was more closely linked to soil chemical status, Brassica carinata appeared predominantly climate-driven. These findings highlight the broader relevance of the study for temperate regions of Central Europe and support the integration of soil fertility management with climate-adaptive strategies when introducing alternative oilseed crops to marginal lands. Full article

The occurrence and concentration of potentially toxic elements (PTE) in fertilizers are a concern in tropical regions, and soil properties affect their bioavailability for crops. Cadmium is the most easily bioavailable for plants and so the food chain, and it represents a stepping-stone toward safe food production. So, this study aimed to evaluate the ionomics, metabolism, and growth of potato, tobacco, and rice in response to liming and to monoammonium phosphates (MAP) from different geographic origins and PTE contents (MAP 1, MAP 2, MAP 3). For this, independent experiments were conducted with each crop using MAP fertilizers as a phosphorus source applied to a Red-Yellow Latosol, with and without liming. Our findings indicated that physiological changes were primarily influenced by liming rather than PTE. Most acidic soils negatively impacted plant growth and sugar content and induced metabolic adjustments related to proline. The higher level of Cd in MAP 3 reduced manganese and zinc and increased sugar in plant shoots. Rice also had a lower Cd bioaccumulation than potato and tobacco, followed by a higher tolerance to acidic soil. The concentrations of As, Cd, and Cr present in fertilizers did not impair the growth and life cycle of the evaluated plants; however, metabolic adjustments were observed. Full article

Phosphorus is an essential and finite resource critical for global food production, yet its inefficient use and discharge from wastewater systems contribute to eutrophication and resource depletion. The transition from conventional wastewater treatment plants to water resource recovery facilities has intensified interest in technologies that enable phosphorus recovery within a circular economy framework. This review provides a critical and up-to-date synthesis of phosphorus recovery strategies from wastewater, with primary emphasis on struvite (MgNH₄PO₄·6H₂O) crystallization as one of the most mature and practically implemented recovery routes. The occurrence and chemical forms of phosphorus in wastewater streams are discussed alongside conventional approaches, such as enhanced biological phosphorus removal and chemical precipitation, in order to position struvite recovery within the broader phosphorus management landscape. In addition to struvite crystallization, selected competing and complementary recovery pathways, including electrochemical systems, biochar-assisted processes, and sludge ash recovery, are discussed to compare technological maturity, recovery potential, and practical applicability. Particular attention is given to reactor configurations, full-scale applications, and commercial technologies to assess operational reliability, recovery performance, and fertilizer product quality. Life-cycle assessment results and regulatory developments are also discussed to contextualize sustainability claims, technology selection, and market integration. The review identifies key technical and economic challenges, particularly regarding magnesium supply, competing ions, wastewater matrix effects, and the feasibility of mainstream application. Overall, controlled sidestream struvite crystallization appears to offer the most favorable balance between recovery efficiency, operational reliability, and fertilizer product quality under suitable plant conditions. Full article