Communications in Soil Science and Plant Analysis

Kaur, Gurleen; Kaur, Harleen; S., Sreethu; Chhabra, Vandna

doi: 10.1080/00103624.2026.2684009pmid: N/A

Agricultural carbon sequestration is an important nature-based strategy for climate mitigation and soil health improvement. This review synthesizes key mechanisms, management practices, and limitations influencing carbon sequestration in agricultural systems. It examines how carbon inputs and stabilization processes regulate long-term SOC storage. Field evidence shows that conservation tillage, residue retention, diversified cropping systems, agroforestry, and biochar application can enhance SOC, but their effectiveness depends strongly on soil type, climate, management duration, and sampling depth. The review also discusses major limitations, including SOC saturation, greenhouse-gas trade-offs, variability in carbon accounting methods, and adoption constraints. Overall, integrated and site-specific management strategies are needed to improve long-term SOC storage while maintaining agricultural productivity and ecosystem resilience.

M, Ramya; P, Nideesh

doi: 10.1080/00103624.2026.2687106pmid: N/A

Humic acid is a complex substance formed from fully decomposed organic matter and contains numerous negatively charged functional groups that hold nutrient ions in the soil. Besides, it forming stable soil aggregates, improves soil aeration, water and nutrient retention and root penetration and is also an ideal food source for soil microbes. Humic acid helps to displace sodium in salt affected soils by allowing calcium and magnesium to take its place, further leaching out the sodium ions. It acts as cementing agent by forming an insoluble three-dimensional structure around the soil particles and helps in resisting soil erosion. Higher resident time of humic acid in soil imparted its further transformation, thus increasing the number of functional groups available for activity of humic acid for soil stabilization. Increase in bioaccumulation of heavy metals during phtoremediation has been widely documented following the addition of humi acid. Its ability to stimulate root growth and enhance nutrient uptake efficiency makes it a superior alternative to many chemical amendments and fertilizers. Integration of humic acid into soil increases crop productivity and minimizes environmental impacts. Optimum dose of humic acid helps in the reclamation of various problematic soils. Due to the low cost and easy availability of humic acid, its usage in agriculture becomes economically feasible. This review aims to demonstrate the superiority of humic acid as a soil amendment by emphasizing its role in enhancing soil health and promoting environmental sustainability.

Aslan, Mehmet Ufuk; Yarsi, Garip; Arslan, Hakan

doi: 10.1080/00103624.2026.2684014pmid: N/A

With rising populations, boosting agricultural productivity is essential. Although chemical fertilizers are common, excessive use increases costs and harms the environment. Zeolite offers an alternative due to its porous structure and cation exchange capacity. In this study, ammonium nitrate was loaded into natural zeolite from Manisa/Türkiye, and the nitrogen content of the fertilizer was 5.80%. Raw zeolite and zeolite-based fertilizer samples were characterized using Brunauer-Emmett-Teller (BET), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR) techniques. The zeolite-based fertilizer was tested on lettuce (Lactuca sativa L) plants in a greenhouse experiment and its usability as a fertilizer and its effect on yield were investigated. According to the results obtained, while the length, leaf number, head diameter, and head weight data of the ZN25 (187.5 ppm Nitrogen) group containing zeolite-based fertilizer were measured as 31.28 cm, 28.88, 16.83 cm and 135.10 g, respectively, for the pure ammonium nitrate applied group (N50; 375 ppm Nitrogen), the related parameters were measured as 29.53 cm, 26, 12.87 cm and 106.80 g, respectively, and it is clear that ZN25 provided better efficiency than N50. Additionally, because of the greenhouse experiment, it was observed that there was a correlation between nitrogen and chlorophyll contents in the application groups. The nitrogen and chlorophyll contents of the ZN25 and N50 groups were measured as 4.29%, 38.14 soil plant analysis development (SPAD) and 5.97%, 43.38 SPAD, respectively. According to these results obtained, zeolite-based fertilizer increased crop yield by using less nitrogen and has the potential to be used in agriculture.

Pramanik, Madhusri; Ghorai, Subhadwip; Biswas, Avijit; Dutta, Abhrajeet; Chatterjee, Avishek; Mukhopadhyay, Ankur

doi: 10.1080/00103624.2026.2687099pmid: N/A

The efficiency of nitrogen (N) and phosphorus (P) use in agriculture remains critically low. While microbial nitrogen fixation and phosphorus solubilization are understood independently, their biological interdependency is frequently overlooked, limiting the development of climate-resilient biofertilizers. This review clarifies the biological mechanisms linking the N and P cycles. At the cellular level, nitrogen fixation is highly energy-intensive, making it strictly dependent on available phosphorus. Conversely, a reciprocal feedback loop exists: as microbes assimilate nitrogen, their growth accelerates, triggering a higher biological demand to scavenge for phosphorus. In soil ecosystems, this mutual dependence creates obligatory partnerships among microbial functional groups, driven by plant root carbon exudates acting as primary metabolic fuel. However, environmental stressors, viz. moisture shifts, salinity, and redox fluctuations, rapidly disrupt these integrated pathways. When these microbial networks fragment, nutrient sharing stops, explaining why traditional, single-function inoculants frequently fail in field conditions. By synthesizing molecular energetics, microbial network ecology, and plant-microbe interactions, this review proposes a community-based approach to biofertilizer design. Sustaining this N-P coupling offers an innovative and sustainable pathway to improve nutrient cycling efficiency in global agriculture.

Asif, Sk Md; De, Parijat; Bhowmick, Udayan Rudra; Dasgupta, Subhadip; Saha, Sushanta; Sen, Arup

doi: 10.1080/00103624.2026.2682382pmid: N/A

Legacy phosphorus (P), accumulated through long-term fertilizer and manure surpluses, represents both a potential nutrient reserve and an environmental concern in agricultural soils. This review synthesizes current understanding of the mechanisms controlling legacy P accessibility, evidence from long-term field studies, and implications for soil diagnostics and adaptive nutrient management strategies. Accessibility of legacy P is regulated by interacting chemical, biological, and physical processes governing phosphate retention and rhizosphere resupply. Evidence from long-term studies indicate that legacy P primarily functions as a finite buffering reserve rather than a fully accessible substitute for fertilizer inputs, with responses varying among soils, climates, and management systems. Current evidence also suggests that crop accessibility to legacy P is governed more strongly by rhizosphere-scale resupply dynamics and soil buffering behavior than by total soil P stocks alone. Conventional soil P tests often inadequately predict crop responses during prolonged fertilizer drawdown because static extractants incompletely represent soil P resupply dynamics. Dynamic and plant-based diagnostic methods may improve assessment of functional P availability under legacy-P conditions, although practical and calibration limitations remain. Effective management of legacy-P-rich soils therefore requires adaptive, site-specific strategies integrating gradual fertilizer drawdown, biologically supportive practices, diagnostic-guided management, and environmental safeguards.

Alam, S M Shamiul; Wei, Lin; Wu, Yajun; Ozor, Tochukwu; Rubel, Robiul Islam; Cidreira, Anne; Shrestha, Manish Man

doi: 10.1080/00103624.2026.2683124pmid: N/A

Heavy reliance on synthetic nitrogen (N) fertilizers has resulted in soil degradation, declining soil productivity, and lower N use efficiency (NUE). Sustainable alternatives such as biochar (BC) and biofertilizers (BFs) offer promising solutions to enhance soil health and support yield improvement. This study investigates the individual and combined effects of BC and microbial BFs on soil properties, corn growth, and yield under controlled greenhouse conditions. A randomized experiment with seven treatments consisting of granular urea, BC, BFs, and their combinations were conducted using clay loam soil. Soil samples collected at four growth stages were analyzed for inorganic N forms, including ammonium-N (NH4 +–N) and nitrate-N (NO3 −–N), as well as organic matter (OM), phosphorus (P), potassium (K), and other physicochemical properties, while plant growth traits, chlorophyll content, biomass, and grain yield were measured. Treatments containing BC and/or BFs significantly increased soil OM and nutrient availability, including N, P, and K. In addition, these treatments improved plant height, leaf number, and chlorophyll concentration, resulting in 14–17% greater biomass and 14–19% higher yield compared to the control. Notably, the integrated application of BC, BFs, and 50% urea treatment increased yield and biomass by 25% and 28%, respectively, values comparable to full urea application, indicating that N fertilizer use can be reduced without compromising productivity. Overall, the results highlight strong synergistic benefits of BC and BFs for sustainable corn production.