1 Introduction

Chrysanthemum (Chrysanthemum morifolium Ramat.) is one of the most important ornamental crops worldwide and also has medicinal and edible value, which makes stable flower yield and quality economically important in commercial production. Because chrysanthemum is a shallow-rooted and nutrient-demanding crop, its growth, flowering, and product quality depend strongly on timely and balanced nutrient supply rather than on soil reserves alone (Gouthami et al., 2026). Current chrysanthemum production therefore relies heavily on fertilizer management, especially the coordinated application of nitrogen, phosphorus, and potassium, to sustain vegetative growth, reproductive development, and marketable inflorescence traits. Experimental work in chrysanthemum has shown that balanced fertilization and stage-specific nutrient delivery can markedly improve plant height, flower traits, biomass accumulation, and soil nutrient status, indicating that fertilizer regime is a decisive management factor in this crop (Choudhary et al., 2022). Likewise, recent studies on medicinal and ornamental chrysanthemum indicate that optimized NPK supply or fertigation enhances flowering performance, chlorophyll accumulation, yield, and fertilizer-use efficiency, reinforcing the need to refine nutrient management strategies under intensive production systems (Jiang et al., 2024).

Despite the productivity benefits of mineral fertilization, chrysanthemum soils often experience nutrient decline and reduced crop performance after repeated cultivation, and this pressure commonly encourages growers to maintain or increase chemical fertilizer inputs. Such a strategy can become counterproductive because excessive nitrogen fertilization is recognized as a major threat to soil health and ecosystem sustainability in plant production systems (Tyagi et al., 2022). Broad evidence shows that chronic overuse of chemical fertilizers degrades soil quality by accelerating acidification, disturbing nutrient balance, reducing organic matter, and disrupting microbial communities that regulate nutrient cycling (Pahalvi et al., 2021). Long-term nitrogen fertilization in China has decreased soil pH by an average of 15.27% and reduced microbial diversity, confirming that heavy fertilizer inputs can weaken the biological basis of soil fertility over time. Excessive and disproportionate fertilizer use also contributes to soil crusting, physiological stress, greenhouse gas emissions, water and air pollution, and in some cases trace-metal accumulation, so maximizing chemical fertilizer input does not ensure sustained productivity and may instead undermine long-term cropping performance.

Against this background, partial replacement of chemical fertilizer with organic fertilizer has emerged as a promising strategy to balance crop nutrition with soil restoration. Across field cropping systems, partial substitution generally improves soil physical structure, raises soil organic carbon, enhances nutrient availability, and supports stable or higher yields compared with sole chemical fertilization (Jiang et al., 2026). Multi-site and long-term studies further suggest that moderate substitution rates are often more effective than either pure chemical fertilizer or complete organic replacement, because they maintain rapid nutrient supply while adding organic matter that supports microbial processes and soil aggregation (Li et al., 2024). In maize systems, relatively low-to-moderate substitution rates increased yield, water-use efficiency, and economic return, while in wheat-maize rotations a 45% substitution rate improved soil fertility and crop productivity and reduced yield-scaled nitrous oxide emissions. Similar benefits have also been reported in rice systems, where replacing 30%-70% of chemical nitrogen with organic nitrogen improved rice yield and soil biochemical indicators, indicating that partial substitution can simultaneously support production and environmental goals across intensive agroecosystems (Dai et al., 2021).

For chrysanthemum, the case for testing partial substitution is especially strong because the crop is frequently grown under intensive fertilization and repeated cultivation, where improvements in soil biological activity and edaphic condition could translate directly into better growth and floral quality. Recent chrysanthemum-specific evidence shows that replacing 20% or 40% of mineral fertilizer with residue-derived organic or bio-organic fertilizer increased plant biomass and quality, raised urease and β-glucosidase activities, alleviated acidification and compaction, and increased available phosphorus in continuously cropped soils (Wang et al., 2026). Organic-based nitrogen management has likewise improved chrysanthemum vegetative growth, with vermicompost plus Bio-NP increasing plant height, spread, and branching, which suggests that organic nutrient sources can effectively support crop development (Mahjoub and Allawi, 2022). Even so, the optimal degree to which chemical fertilizer can be replaced by organic fertilizer in C. morifolium while sustaining growth and improving soil fertility remains insufficiently defined. A study focused on partial chemical fertilizer replacement in chrysanthemum is therefore needed to identify substitution rates that maintain crop performance while promoting healthier and more sustainable soil conditions (Jiang et al., 2026).

2 Effects of Partial Chemical Fertilizer Replacement on Chrysanthemum Growth

2.1 Plant growth and biomass accumulation

Partial replacement strategies consistently enhanced vegetative growth and biomass accumulation in chrysanthemum when organic inputs were combined with reduced mineral fertilization rather than used as a simple full substitute. In a biennial cut-flower study, integrated nutrient management with 50% mineral fertilizer replacement plus organic N, seaweed extract, and a microbial consortium increased yield at harvest by 19%, leaf number by 33%, leaf area by 46%, and total aboveground dry weight by 40% relative to conventional mineral fertilization. In Chrysanthemum morifolium, low-proportion replacement also maintained productivity, and 14% organic fertilizer substitution increased flower yield by 8.3% compared with chemical fertilizer alone, indicating that modest substitution can sustain or improve biomass formation while reducing chemical input (Xu et al., 2021).

Related chrysanthemum studies using organic nutrient sources support the same growth pattern, even when the treatments were not framed as exact replacement ratios. Enriched FYM plus vermicompost and seaweed extract produced the tallest plants, widest spread, most branches, and highest leaf number in spray chrysanthemum, showing that multi-source organic supplementation can strongly stimulate canopy development. Likewise, bio-organic fertilizer and residue-based substitution improved plant biomass under continuous chrysanthemum monoculture, with shoot height rising by 31.4% in one greenhouse study and biomass increasing significantly in a two-year continuous-cropping system, suggesting that organic replacement is especially valuable where long-term mineral fertilization has degraded soil function (Wang et al., 2026).

2.2 Root development and nutrient uptake

Root responses are one of the clearest advantages of replacing part of the mineral fertilizer input with organic sources. Liquid organic fertilizers promoted chrysanthemum root growth by 10.2%-77.8% over chemical fertilizer, and the shrimp-extract treatment increased root dry weight, total length, surface area, volume, tips, and thick-root length more than the mineral NPK control. A chitosan organic water-soluble fertilizer produced a similar pattern at the seedling stage, where the optimal dilution increased total root length by 46%, root surface area by 62%, and root volume by 69%, alongside large increases in root and shoot fresh weight.

The same root improvements translated into greater nutrient accumulation under integrated or partial replacement regimes. In the biennial integrated nutrient management trial, replacing half of the mineral fertilization with organic fertilizer, seaweed extract, and beneficial microbes increased root length by 174%, root volume by 167%, and root surface area by 165%, while also producing the greatest N accumulation at harvest. In field-grown C. morifolium, increasing organic substitution raised flower N and Mg contents, with Ca peaking at 56% replacement and P at 28% replacement, and the authors concluded that 28% substitution gave the best overall balance among yield, nutrient absorption, active compounds, and ecological performance (Xu et al., 2021).

2.3 Flowering characteristics and ornamental quality

Flowering responses indicate that partial replacement can improve both productivity and ornamental value when nutrient release is synchronized with crop demand. In C. morifolium, low-to-moderate organic substitution maintained yield and improved flower composition, while chlorogenic acid, luteolin, and 3,5-O-dicaffeoylquinic acid increased progressively with greater organic replacement; based on combined yield and quality indices, 28% substitution was judged optimal. In cut chrysanthemum, bio-organic fertilizer also improved ornamental traits under monoculture stress, increasing ray floret number by 26.1% while sharply suppressing Fusarium wilt, which links better floral display with healthier rhizosphere conditions (Chen et al., 2025).

Broader chrysanthemum fertilizer studies reinforce that organic enrichment often improves earliness, stem quality, flower size, and marketable yield, although responses vary by formulation. Jeevamrut plus Panchagavya accelerated first bud initiation, first flower opening, and full bloom, while also producing 35.52 flowers per plant, 141.39 g flower yield per plant, and 6.32 cm flower diameter (Pansuriya and Kumari, 2024). Organic matter combinations and recycled chrysanthemum residues also improved marketable flower weight and stem-related quality traits, with the best treatments increasing economic fresh flower weight by about 10-11% and raising stalk length, stalk weight, and flower diameter to commercial grade-A standards (Arjana and Andriani, 2025).

3 Effects on Nutrient Availability and Fertilizer Use Efficiency

3.1 Nitrogen, phosphorus, and potassium availability

Partial replacement of chemical fertilizer with organic inputs generally increases the available, rather than total, pools of nitrogen, phosphorus, and potassium in soil. In gray desert soil, three years of substitution increased soil available N, P, K, and organic matter with rising replacement ratio, with the strongest gains at the 18% and 24% substitution levels (Lu et al., 2024). A six-site Vertisol study similarly found that partial organic substitution kept total N, P, and K broadly comparable to NPK alone, but increased nutrient availability by 2.1%-23.7%, with available pools responding more strongly than total nutrient stocks (Jiang et al., 2026).

Evidence from chrysanthemum systems indicates that organomineral inputs can also sustain or enhance macronutrient availability under ornamental cultivation. In continuously cropped cut chrysanthemum soil, bio-organic fertilizer substitution produced the greatest fertility response, with soil available phosphorus peaking at 114.6 g/kg, while redundancy analysis identified soil pH and available phosphorus as major drivers of the reassembled soil community (Wang et al., 2026). In chrysanthemum cultivar Singelo, fertilization with ash-based organic or organomineral sources increased soil potassium by 77% relative to treatments without ash, and organomineral fertilizer was identified as a practical alternative for maintaining high soil macronutrient levels into a second crop cycle (Meneghetti et al., 2025).

Although nutrient availability usually improves, the most effective substitution ratio is not always the highest one. In Vertisols, 15% manure substitution often outperformed 30% substitution for available nutrient supply across sites, and 30% substitution occasionally fell below NPK, suggesting that excessive replacement can create local nutrient constraints despite gains in soil quality (Jiang et al., 2026). A long-term paddy-soil study reached a similar conclusion for nitrogen dynamics, showing that organic substitution enhanced N retention overall but that 50% substitution optimized both immobilization capacity and fertilizer utilization better than the highest organic share (Hou et al., 2024).

3.2 Nutrient uptake and utilization efficiency

Improved soil nutrient availability under partial substitution usually translates into higher plant nutrient uptake and better fertilizer use efficiency. In Chrysanthemum morifolium residue-based biofertilizer systems, organic substitution significantly enhanced plant biomass and quality while increasing urease and β-glucosidase activity, indicating a stronger biochemical basis for nutrient supply and crop acquisition under reduced mineral fertilization (Wang et al., 2026). In marigold, integrated nutrient management with vermicompost and biofertilizers plus 50% recommended fertilizer increased flower N, P, and K uptake and improved apparent P and K recovery, showing that ornamental crops can maintain high nutrient capture even when mineral inputs are partly reduced.

Broader crop evidence supports the same efficiency pattern and helps define its likely operating range. In wheat, integrated management with legume biomass or farmyard manure increased nitrogen use efficiency by 1.3-2.0-fold compared with full inorganic fertilization, while also providing a season-long N supply equivalent to or greater than 100% mineral fertilizer at several critical stages. In tea plantations, both partial and full organic substitution increased nitrogen utilization efficiency of young shoots, with the largest gain reaching 82.54% above conventional fertilization under a sheep-manure-based partial replacement treatment (Wang et al., 2024).

A moderate organic share often gives the best balance between nutrient recovery and immediate nutrient supply. In yam, the 25% organic + 75% chemical treatment produced the highest nitrogen accumulation and the greatest apparent N utilization, agronomic efficiency, and partial factor productivity, outperforming both sole organic fertilizer and higher substitution ratios. Strawberry results were more nuanced: integrated organic-inorganic fertilization improved apparent nutrient recovery overall, but the highest recoveries varied by nutrient, with K and Zn peaking under poultry manure plus high NPKSZnB, while N and P recovery remained highest under fully inorganic fertilization (Quddus et al., 2025).

3.3 Nutrient release and synchronization with chrysanthemum demand

The central mechanism behind higher efficiency in partial substitution systems is nutrient synchrony: mineral fertilizer supplies readily available nutrients early, while organic fertilizer prolongs release into later growth stages. Reviews of combined nutrient management identify synchronizing nutrient release with crop uptake as critical for reducing losses and improving efficiency, and describe the joint use of organic and inorganic fertilizers as effective because mineral fertilizer releases nutrients immediately while organic sources stagger supply later in crop development. Experimental evidence agrees that combined substrates improve N management by better matching plant uptake requirements across the growing season, with combination treatments doubling NUE and halving N runoff relative to inorganic fertilizer alone in one runoff study.

This synchrony principle is directly relevant to chrysanthemum because its nutrient demand changes across vegetative growth, bud formation, and flowering, so a single fast-release source can miss later demand peaks. Organic fertilizers vary widely in short-term N release, from nearly zero mineral fertilizer equivalence in some composts to almost full equivalence in urine-based materials, making fertilizer quality and composition decisive for matching crop demand (Diener et al., 2026). In hydroponic lettuce, mismatches between organic nutrient release and plant demand reduced biomass under standard organic dosing, whereas a higher-dose customized organic mix restored yields close to conventional fertilization, illustrating how yield depends on aligning release rate with growth-stage demand (Son et al., 2026).

Studies that explicitly manipulated release timing show why synchronized fertilization can outperform conventional schedules. In banana, a fertilization program designed from crop uptake patterns and fertilizer release characteristics increased N, P, and K accumulation by 8.66%, 11.54%, and 19.55%, and raised nutrient use efficiency for all three nutrients over conventional fertilization. Controlled-release nitrogen studies reached the same conclusion mechanistically: when nitrogen release was synchronized with crop demand, later-stage soil inorganic N remained higher, post-anthesis dry matter increased, and NUE improved, supporting the idea that chrysanthemum should also benefit from partial replacement strategies that balance immediate mineral nutrition with slower organic release (Figure 1) (Quan et al., 2021).

Figure 1 Conceptual model of nutrient-release synchrony under mineral, organic, and combined fertilizer strategies

4 Effects on Soil Physical and Chemical Properties

4.1 Soil organic matter and soil structure

Partial replacement of chemical fertilizer with organic fertilizer generally increases soil organic matter and improves soil physical structure, which is a central mechanism linking fertilization strategy to better soil fertility. Across field studies, partial substitution reduced soil bulk density and increased soil organic carbon, while broader synthesis shows that organic inputs also improve aeration, water permeability, and porosity relative to chemical fertilizer alone (Chen et al., 2025). Evidence from aggregate-based studies shows that these structural gains extend beyond bulk density into more stable soil architecture. In tea plantation soil, 30% substitution with organic materials increased mean weight diameter and geometric mean diameter while reducing fractal dimension, disruption rate, and erodibility, and in anthropogenic-alluvial soil, organic substitution increased water-stable macroaggregates and raised mean weight diameter by 24.18%-30.22% in the final year (Huang et al., 2023).

Longer-term substitution also increases carbon-rich structural fractions that support soil stability. In wheat-maize rotation, partial substitution increased total organic carbon and, when combined with straw return, significantly improved soil fertility, while in sorghum soil, SOC rose progressively with substitution ratio and was 24.25% higher than chemical fertilizer under the 50% replacement treatment (Li et al., 2024). This pattern is relevant to Chrysanthemum morifolium because chrysanthemum continuous-cropping systems respond strongly to organic inputs through soil rehabilitation. In chrysanthemum residue-based fertilization, bio-fertilizer substitution showed the greatest potential for improving soil fertility, and in long-term tea soil the BFG and related substitution treatments increased soil organic matter by 13.22%-14.88%, indicating that partial replacement can rebuild depleted organic pools under intensive horticultural management (Pan et al., 2025).

4.2 Soil pH, electrical conductivity, and nutrient accumulation

Partial organic substitution often moderates adverse pH shifts caused by sole chemical fertilization, although the direction and magnitude depend on initial soil conditions and organic material type. Long-term wheat-maize evidence shows that chemical fertilizer alone acidified soil, whereas organic fertilizer application alleviated acidification, and paddy-soil results similarly found that substitution significantly increased pH relative to chemical fertilizer alone (Wei et al., 2025). At the same time, pH responses are not uniform across all systems. In maize rhizosphere soil, manure substitution reduced both pH and electrical conductivity while increasing nutrient levels, whereas in calcareous continuous-maize soil, one-third substitution maintained relatively stable pH but sole organic fertilization increased EC by 10.04%, showing that moderate replacement is usually safer than full substitution where salinity risk exists (Ren et al., 2021; Liu et al., 2026).

Nutrient accumulation under partial substitution is more consistent than pH behavior. In Vertisols, total N, P, and K remained comparable to NPK but nutrient availability improved by 2.1%-23.7%, while gray desert soil showed that available N, P, K, and organic matter all increased with substitution ratio after three consecutive years (Jiang et al., 2026). Rhizosphere-focused studies further show that nutrient enrichment is coupled to biologically favorable soil conditions. In Albic soybean soil, partial substitution significantly enhanced rhizosphere pH, organic matter, and available phosphorus, and in sorghum soil the medium substitution treatment increased TN, TP, AN, and AP while AP continued to rise with increasing substitution ratio (Nie et al., 2024).

4.3 Soil carbon and nutrient cycling

Partial substitution does not only add carbon to soil; it changes the way carbon is stored, transformed, and linked to nutrient turnover. A recent synthesis states that partial substitution increases SOC pool stability and nutrient utilization, and a soybean rhizosphere study similarly found that it enhances carbon sequestration capacity and stimulates enzymes critical to nutrient cycling (Pan et al., 2025). Active carbon fractions respond particularly strongly to these treatments. In a maize field study, 12.5% substitution increased easily oxidizable organic carbon, SOC, and particulate organic carbon, while deeper layers under 37.5% substitution gained microbial biomass carbon and hot-water-soluble carbon, indicating that even modest replacement can activate multiple carbon pools (Chen et al., 2025). Mechanistic studies also show that moderate substitution can slow carbon loss while enlarging active carbon reservoirs. In yellow paddy soil, replacing 50% of chemical N with organic fertilizer inhibited SOC mineralization and increased ROC and DOC relative to chemical fertilizer alone, and in northeast China higher manure ratios increased particulate organic carbon and total SOC while raising microbial biomass carbon by 18.3%-53.0% (Wei et al., 2025).

These carbon changes are tightly coupled to nutrient cycling through enzymes and microbial communities. Substitution treatments increased urease, phosphatase, and related enzyme activities in several systems, and a three-year ecosystem-function study identified 30% substitution as the optimal ratio because it enhanced nutrient content, enzyme activity, and beneficial microbial groups without requiring the highest organic input (Lu et al., 2024). For chrysanthemum production, this means that partial chemical fertilizer replacement is likely to improve soil function not only through higher nutrient stocks, but through more active and resilient carbon-nutrient cycling. The strongest evidence supports moderate substitution rates that improve SOM, stabilize structure, moderate pH and EC, and enhance biologically mediated nutrient turnover rather than complete replacement of mineral fertilizer.

5 Effects on Soil Biological Properties and Microbial Communities

5.1 Soil microbial biomass and enzyme activities

Partial replacement of chemical fertilizer with organic fertilizer generally increases soil biological activity by stimulating microbial biomass and key extracellular enzymes involved in carbon, nitrogen, and phosphorus turnover. In maize rhizosphere soil, organic manure substitution increased urease, invertase, and alkaline phosphatase activities together with nutrient levels, while a long-term wheat-rice rotation showed that organic inputs increased microbial biomass carbon relative to chemical fertilizer alone (Ren et al., 2021). This pattern is consistent with the view that organic amendments provide carbon and energy substrates that support microbial proliferation and biochemical activity, rather than acting only as slow nutrient sources. Rate effects are important, because biological gains do not always rise linearly with more organic substitution. In a mountain red soil maize system, cellulase, invertase, β-glucosidase, N-acetylglucosaminidase, urease, and leucine aminopeptidase increased with substitution ratio, but several enzyme activities peaked around 30% substitution, indicating a biological optimum below full replacement. A recent multi-year field study similarly found that partial substitution significantly increased soil nutrient content and enzyme activity, but higher organic substitution did not produce a significant further increase, with 30% replacement identified as the optimal proportion in that region (Lu et al., 2024).

Microbial biomass responses also extend into aggregate-scale soil organization, which is relevant to long-term soil fertility under intensive horticulture. In an eight-year gravel-mulched field, increasing the proportion of organic fertilizer raised microbial biomass carbon, microbial biomass nitrogen, phospholipid fatty acids, and related enzyme activities across aggregate size classes, especially when substitution exceeded 50% (Tang et al., 2024). In a 12-year rubber plantation, half substitution increased microbial biomass carbon together with labile carbon fractions such as particulate organic carbon and hot-water-extractable carbon, showing that microbial biomass expansion is closely tied to broader carbon pool enrichment (Xu et al., 2023). For chrysanthemum systems, these biological responses are important because enzyme activation and microbial biomass recovery help explain why organic substitution alleviates continuous-cropping stress. In cut chrysanthemum residue-based fertilization, bio-fertilizer substitution markedly increased urease and β-glucosidase activity and improved plant biomass and quality, indicating active microbial restoration of degraded soil function (Sun et al., 2024). A mild-substitution study in another cropping system reached a similar conclusion, with 20% substitution producing the strongest gains in alkaline phosphatase, urease, and invertase and simultaneously promoting beneficial taxa while suppressing pathogens (Wang et al., 2024).

5.2 Changes in soil microbial community structure

Partial chemical fertilizer replacement changes microbial community structure more consistently than it changes alpha diversity. In maize rhizosphere soil, substitution had a stronger effect on bacterial than fungal diversity and significantly altered community composition, particularly among dominant bacterial phyla such as Actinobacteria (Ren et al., 2021). A two-year field study similarly found that substitution did not significantly change alpha diversity but did reshape community composition, and the 40% treatment produced more pronounced enrichment of beneficial groups than 20% or 60% substitution (Sun et al., 2024). The taxa favored by substitution are often those associated with decomposition, nutrient release, and disease suppression. Organic fertilizer treatments enriched beneficial groups including Proteobacteria, Acidobacteriota, Basidiomycota, Vicinamibacteraceae, Botryotrichum, and Tausonia while suppressing Fusarium in one maize study. In chrysanthemum-related continuous-cropping recovery, bio-organic fertilizer reduced Fusarium wilt by 82.8%, supporting the idea that community restructuring under organic substitution can directly improve rhizosphere health as well as fertility (Lei et al., 2024).

Network-level evidence shows that substitution does not merely swap taxa; it often creates more connected and stable microbial assemblages. In soybean rhizosphere soil, partial substitution significantly strengthened bacterial interrelationships, increasing average degree and network density and producing a more compact and complex bacterial network (Pan et al., 2025). Long-term garlic fertilization showed the same pattern, with 40% substitution increasing bacterial and archaeal co-occurrence complexity and enriching beneficial microbes linked to nutrient cycling and plant growth. These shifts are not unlimitedly beneficial, and higher substitution rates can introduce new constraints. In an 11-year double-cropping system, 50% substitution increased SOM and available nutrients but reduced annual yield by 9.49%-16.78% because it suppressed keystone taxa associated with carbon enzyme activity and productivity (Lei et al., 2024). Facility-vegetable soils likewise showed that the best diversity and evenness depended on cultivation history, with 25% substitution outperforming higher ratios in older soils, indicating that the optimal microbial response is context dependent rather than universally maximal at the highest organic share (Guo et al., 2025).

5.3 Interactions between microorganisms, nutrient cycling, and plant growth

The main agronomic value of microbial change under partial substitution is that microorganisms mediate nutrient cycling rather than simply co-occurring with improved soil chemistry. Path analysis in sorghum showed that microorganisms influenced yield both directly through microbial community diversity and indirectly through effects on pH, bulk density, enzyme activities, and soil nutrients. In foxtail millet, bacteria and fungi also influenced yield indirectly via enzyme activity and nutrient interactions, while organic substitution improved soil carbon and nitrogen metabolism and increased plant nitrogen uptake (Nie et al., 2025). Several studies identify specific biological pathways linking microbial shifts to nutrient turnover. In saline-alkaline soil, structural equation modeling showed that organic substitution altered SOC, mineral N, salinity, and available phosphorus, which then regulated microbial carbon and nitrogen resource limitations and reshaped bacterial and fungal communities (Han et al., 2025). In apple orchard soil, higher SOM and C/N ratio changed the abundance of Proteobacteria, Ascomycota, and Crenarchaeota that were closely related to SOM and nitrogen decomposition and mineralization, while increased sucrase, urease, and phosphatase promoted nutrient conversion efficiency.

Organic substitution also improves the functional capacity of microbial communities to use carbon substrates and support fertilizer efficiency. In rain-fed wheat, substitution increased the partial productivity of fertilizer and altered microbial carbon-source utilization, with carbohydrates and amino acids showing the strongest treatment sensitivity and the highest substitution treatment promoting taxa such as Pseudomonas linked to nitrogen metabolism (Liu et al., 2023). A bio-organic fertilizer study reached a similar mechanistic conclusion: introducing functional microorganisms and organic matter optimized the soil microenvironment, increased organic nitrogen metabolism genes, reduced denitrification genes, and improved C/N use efficiency and plant growth. For Chrysanthemum morifolium, these findings support a clear interpretation: partial chemical fertilizer replacement improves soil biological fertility not only by increasing microbial abundance, but by fostering functionally favorable communities that accelerate nutrient turnover, suppress pathogens, and strengthen plant growth. The strongest evidence favors moderate substitution, because it usually delivers the best balance between enzyme activation, beneficial community restructuring, and stable crop performance without the ecological trade-offs sometimes seen at very high replacement ratios.

6 Case Study: Partial Chemical Fertilizer Replacement in Chrysanthemum Production

6.1 Experimental design and fertilizer replacement treatments

A representative chrysanthemum case-study design is the two-year trial in 12-year continuously cropped soil, where 20% and 40% of mineral fertilizer were replaced on an equivalent nitrogen basis with either chrysanthemum-residue compost or Bacillus subtilis-inoculated bio-organic fertilizer (Wang et al., 2026). This design is methodologically consistent with broader substitution experiments that compare several graded replacement levels against a full chemical-fertilizer control, as in the field framework using 20%, 40%, and 60% organic substitution under an equivalent nitrogen principle with balanced phosphorus and potassium supply across fertilized treatments.

Another chrysanthemum-based design comes from Chrysanthemum morifolium trials using five replacement ratios: 0%, 14%, 28%, 56%, and 84% organic fertilizer substitution for chemical fertilizer, allowing simultaneous assessment of agronomic traits, nutrient absorption, and quality indices across a wide substitution gradient (Xu et al., 2021). Complementary production-oriented studies also used randomized block layouts with multiple organic input combinations and repeated applications over the season, such as the 14-treatment chrysanthemum experiment based on Jeevamrut and Panchagavya schedules, and the 10-treatment nitrogen-management trial designed to identify the best organic source plus bio-input combination (Pansuriya and Kumari, 2024).

6.2 Responses of chrysanthemum growth and soil fertility

Across chrysanthemum studies, partial substitution generally improved plant performance relative to chemical fertilizer alone, especially under low-to-moderate replacement. In C. morifolium, combined organic and chemical fertilization maintained yield, and the 14% replacement treatment increased yield by 8.3%, while in continuously cropped cut chrysanthemum, organic substitution significantly enhanced plant biomass and quality parameters, particularly under the higher-rate bio-organic fertilizer treatment in the second year (Xu et al., 2021). Similar positive responses were also seen in chrysanthemum systems using alternative organic inputs, where liquid organic fertilizers promoted root and aboveground growth by 10.2%-77.8% and 10.7%-33.3%, and where optimized Jeevamrut plus Panchagavya treatment maximized vegetative growth, flowering, and flower yield per plant (Pansuriya and Kumari, 2024).

Soil fertility responses were equally important in these case studies because partial replacement consistently alleviated degradation associated with intensive chrysanthemum production. In the residue-derived biofertilizer study, organic substitution increased soil pH by 18.0%-21.4%, reduced compaction, and raised available phosphorus to 114.6 g/kg under the biofertilizer treatments (Wang et al., 2026). The same pattern of soil improvement appears in other chrysanthemum-focused systems: shrimp-extract liquid organic fertilizer increased rhizosphere nutrient contents and altered the functional microbial community, while Chinese herbal compound fertilizer changed soil physical and chemical properties and increased chrysanthemum yield and tea quality (Figure 2).

Figure 2 Effects of partial substitution of chemical fertilizer with organic inputs on growth, biomass accumulation, flowering, and yield of chrysanthemum

6.3 Determination of an appropriate replacement ratio

The most appropriate replacement ratio in chrysanthemum appears to be moderate rather than maximal, but the exact optimum depends on the production goal. For medicinal and quality-oriented C. morifolium, the most comprehensive chrysanthemum-specific evidence supports 28% substitution, because that treatment gave the best overall balance among yield, nutrient absorption, active ingredient content, antioxidant activity, and ecological performance (Xu et al., 2021). For continuous-cropping remediation in cut chrysanthemum, stronger substitution with bio-organic fertilizer was more effective for restoring soil function and suppressing Fusarium oxysporum, indicating that a somewhat higher ratio can be justified when the main objective is soil rehabilitation rather than only short-term yield (Wang et al., 2026).

Broader ratio-comparison studies help explain why chrysanthemum optima cluster in the low-to-moderate range. Across crops, the best-performing treatments were often 8-45% substitution rather than the highest rates, including 8% in maize for yield, soil fertility, and low pollution risk, and 30% in Vertisols for the most consistent gains in soil quality and yield stability (He et al., 2022; Jiang et al., 2026). Evidence from other long-term systems points in the same direction: 45% substitution improved soil fertility, yield, and N₂O mitigation in wheat-maize rotation, whereas 50% substitution optimized nitrogen immobilization and fertilizer utilization in paddy soil, supporting the conclusion that chrysanthemum production should generally target a moderate partial replacement range and refine it according to whether the priority is flower yield, medicinal quality, or recovery of degraded continuous-cropping soil (Hou et al., 2024).

7 Mechanisms and Sustainable Implications of Organic Fertilizer Substitution

7.1 Plant-soil feedback under integrated fertilization

Under integrated fertilization, plant-soil feedback is strengthened because organic inputs improve rhizosphere structure, nutrient retention, and microbial activity while mineral fertilizer supplies readily available nutrients during early growth. In rhizosphere-focused work, partial substitution enhanced pH, organic matter, and available phosphorus, and these changes were linked to a healthier inter-root environment that supports nutrient conversion and root acquisition (Pan et al., 2025). This feedback is biologically mediated as much as chemically mediated. Partial substitution altered microbial community composition more strongly for bacteria than fungi and changed enzyme activity indirectly through microbial shifts, showing that plant performance depends on how fertilization reorganizes the rhizosphere biota rather than only on nutrient inputs (Ren et al., 2021). The interaction is reinforced by evidence that beneficial taxa enriched under substitution promote nutrient cycling and that yield is positively associated with available phosphorus, potassium, total nutrients, and urease activity (Lu et al., 2024).

In chrysanthemum-relevant terms, this means that partial replacement does not act as a simple nutrient swap but as a root-soil regulation strategy. Integrated nutrient supply can maintain a more continuous release pattern across crop development, while organic matter inputs improve the physical and biological environment in which chrysanthemum roots absorb nutrients and resist continuous-cropping stress. Long-term half-substitution also increased pH, available phosphorus and potassium, microbial biomass carbon, and several labile carbon pools, indicating that feedbacks between roots, microbes, and carbon turnover become more favorable under mixed fertilization than under mineral fertilizer alone (Xu et al., 2023). These mechanisms help explain why moderate substitution often outperforms both extremes. In a six-site study, yield gains were mediated mainly through improved nutrient availability, soil quality, and stoichiometric balance, while in wheat-rice rotation partial substitution restored bacterial richness and produced the highest yields over seven years (Jiang et al., 2026). The linkage between aggregate formation, microbial biomass, and enzyme activity is especially clear in long-term aggregate analyses, where larger, more stable aggregates co-occurred with higher microbial carbon and hydrolytic enzyme activity.

7.2 Balancing chrysanthemum productivity and soil fertility

The main agronomic challenge in chrysanthemum is to reduce chemical fertilizer without weakening flower yield and quality, and the broader evidence indicates that this balance is usually achieved at moderate substitution ratios rather than maximum replacement. Partial substitution has been explicitly described as a strategy that balances yield increase with soil fertility improvement, but higher substitution ratios can cause nutrient-release mismatch, salinity risk, or lower immediate fertilizer efficiency. In maize and Vertisol studies, the best-performing treatments were commonly around 30%-40% substitution, which improved soil nutrients, organic matter, and yield more consistently than either full chemical fertilizer or higher replacement levels. Long-term evidence also shows why “more organic” is not always better. In an 11-year double-cropping system, 30% substitution preserved soil fertility and microbial function with stable yield, whereas 50% substitution increased SOM and available nutrients but reduced yield by suppressing keystone microbial species tied to carbon enzymes and productivity (Lei et al., 2024). A mild-substitution study similarly found that 20% replacement gave the strongest improvements in enzyme activity and beneficial taxa while maintaining yield, supporting the idea that biological optimization can occur below the highest organic input level (Wang et al., 2024).

For Chrysanthemum morifolium, these patterns support using replacement ratios that match the production goal rather than assuming a universal optimum. Where the priority is routine flower production, moderate substitution is most likely to maintain productivity while rebuilding soil organic matter, nutrient availability, and rhizosphere biological activity. Where the priority is rehabilitation of degraded continuous-cropping soil, somewhat stronger bio-organic input may be justified because substitution can stimulate enzyme activity, beneficial microbes, and soil ecosystem functions that chemical fertilizer alone does not restore (Lu et al., 2024). The balancing mechanism is therefore a trade-off management problem rather than a single-input problem. Moderate substitution tends to synchronize nutrient release with crop demand, increase soil quality index and nutrient-use pathways, and support yield stability across sites. By contrast, sole organic fertilization often cannot meet high-yield demand, while excessive substitution can weaken short-term crop response even if some soil indicators continue to rise (Wang et al., 2024).

7.3 Environmental and economic benefits

The clearest sustainable implication of partial substitution is that it can reduce the environmental burden of intensive fertilization while maintaining or increasing returns. In vegetable systems, partial substitution lowered N₂O emission, N leaching, and runoff because inorganic nitrogen surplus was reduced, and the same study reported 37%-46% higher economic benefit per unit area with lower input and environmental costs per unit product (Tang et al., 2021). Life-cycle evidence likewise showed that mixed organic-inorganic strategies reduced carbon footprint by 17.0%-21.8% and reactive nitrogen footprint by 34.1%-43.0%, while improving net ecosystem economic benefits. These benefits depend on proportion. In summer maize, 15%-30% substitution increased yield, water-use efficiency, and net benefit, whereas 45%-60% substitution did not improve returns over chemical fertilizer alone. In dryland wheat, manure reduced the synthetic N needed to reach maximum yield, increased net economic benefit by 10.2%, and improved water storage in ways that promoted N uptake and reduced reactive N losses (Li et al., 2024).

The same logic is relevant to chrysanthemum production systems, where profitability depends not only on flower yield but also on preserving soil function in intensive, repeated cultivation. Partial substitution has been framed as a circular economy strategy because it recycles organic wastes into nutrient sources while improving soil properties and sustaining crop yields (Chen et al., 2025). In greenhouse muskmelon, which is agronomically closer to high-input horticulture than grain systems, 15%-30% substitution increased soil nutrients and net benefit by 5.60%-14.9%, suggesting that intensive chrysanthemum systems could realize similar economic gains when moderate replacement reduces fertilizer dependence without sacrificing marketable output. A broader ecosystem-service perspective also supports partial substitution over sole chemical fertilizer. In peri-urban vegetable production, partial replacement increased annual yield and SOC sequestration while cutting greenhouse-gas emissions and total reactive nitrogen losses, producing higher net economic benefit despite added labor or organic-input costs. Overall, for Chrysanthemum morifolium, the most sustainable path is likely moderate partial replacement that preserves flower productivity, improves soil fertility, and lowers long-term environmental and economic risk rather than maximizing either chemical or organic fertilizer alone.

8 Conclusions and Future Perspectives

Partial replacement of chemical fertilizer with organic fertilizer consistently improved soil fertility, nutrient availability, and biological activity relative to sole chemical fertilization, while also supporting stable or higher crop productivity under moderate substitution rates. In chrysanthemum systems, this pattern was directly reflected by better plant biomass and quality, reduced soil acidification and compaction, and higher available phosphorus under bio-organic substitution in continuously cropped soil. The underlying benefits appear to arise from simultaneous improvement of soil physical, chemical, and microbial functions rather than from nutrient addition alone. Chrysanthemum-specific evidence also shows that integrating organic fertilizer can maintain yield while improving medicinal quality traits, with increases in chlorogenic acid, luteolin, and related bioactive compounds across substitution treatments. Moderate substitution also tends to strengthen soil carbon pools and nutrient cycling, which helps explain its longer-term fertility effects. In older chrysanthemum fertilization work, organic manures increased soil organic carbon and light-fraction organic carbon and improved humus composition more effectively than chemical fertilizer, indicating that the soil-restorative effect is relevant to this crop as well as to field crops. At the same time, the evidence does not support unlimited increases in organic substitution. Full or excessive substitution can reduce short-term yield or weaken fertilizer efficiency because nutrient release may not match crop demand as closely as integrated fertilization does. This trade-off is consistent with chrysanthemum observations showing that low-to-moderate replacement maintained or improved yield, whereas the best treatment depended on whether the target was yield, quality, or soil rehabilitation.

For Chrysanthemum morifolium production, the most defensible strategy is a moderate, nitrogen-equivalent partial replacement of chemical fertilizer with well-characterized organic inputs rather than either sole chemical fertilizer or complete substitution. Chrysanthemum-specific trials support this approach: 14% substitution increased yield, while 28% substitution gave the best overall balance among nutrient uptake, active ingredients, antioxidant activity, and ecological performance. Where the production goal is early vegetative establishment or rhizosphere activation, liquid organic sources can be integrated strategically at specific growth stages. Where the goal is flower yield and vegetative growth under practical horticultural conditions, organic input schedules such as Jeevamrut and Panchagavya combinations also performed well, indicating that replacement design should consider fertilizer form and application timing, not only substitution percentage. For degraded continuous-cropping chrysanthemum soils, somewhat stronger bio-organic substitution may be justified because the objective extends beyond immediate yield to recovery of soil ecological function. Even so, the broader literature suggests that optimization should remain cautious and site-specific, since the agronomic optimum in many systems falls in the low-to-moderate range, often around 15%-40%, rather than at the highest replacement ratio. A practical chrysanthemum fertilization strategy should therefore match substitution ratio to production objective, soil condition, and organic fertilizer quality. For routine commercial production, moderate substitution appears most likely to preserve flower yield while improving soil organic matter, nutrient availability, and microbial activity over time.

Future research should move beyond simple yield comparisons and resolve how organic fertilizer type, substitution ratio, and crop growth stage interact in chrysanthemum systems. This is especially important because current chrysanthemum studies span residue composts, bio-organic fertilizers, liquid extracts, and traditional organic inputs, but still provide limited side-by-side evidence on which materials best match nutrient demand across vegetative growth, budding, and flowering. Longer-term chrysanthemum experiments are also needed to identify whether the best short-term ratio remains optimal after repeated cultivation and whether benefits saturate over time. Multi-year trials should include continuous-cropping soils, because current chrysanthemum evidence already shows that bio-organic substitution can reorganize microbial networks and suppress Fusarium under long-term soil stress. Another priority is to integrate agronomic, ecological, and quality endpoints in one evaluation framework rather than optimizing a single output. For medicinal chrysanthemum in particular, future studies should jointly quantify flower yield, active constituents, nutrient-use efficiency, soil quality, and economic return so that recommended substitution ratios reflect the crop’s dual role as an ornamental and medicinal plant. Environmental assessment should also become routine in chrysanthemum fertilization research. Broader evidence shows that partial substitution can reduce N₂O emissions and N losses, but greenhouse-gas responses depend on substitution rate, organic C content, and production system, so chrysanthemum-specific life-cycle and emission data are still missing. Economic analysis is equally necessary, because adoption will depend on whether soil and quality benefits offset the higher handling or material costs of organic inputs under commercial floriculture conditions.

Acknowledgments

I extend my sincere gratitude to the anonymous reviewers for their valuable and insightful comments, which have greatly strengthened this paper.

Conflict of Interest Disclosure

The author affirms that this research was conducted without any commercial or financial relationships that could be construed as a potential conflict of interest.

References

Arjana I.G.M., Sudewa K.A., and Andriani A.P.R., 2025, Utilization of combinations of organic matter in chrysanthemum plant cultivation, AJARCDE (Asian Journal of Applied Research for Community Development and Empowerment), 9(1): 229-235.

https://doi.org/10.29165/ajarcde.v9i1.510

Chen Q., Xie J.H., Li L.L., Khan K.S., Wang L., Chang L., and Du C.L., 2025, Partial substitution of chemical fertilizer with organic fertilizer: a promising circular economy approach for improvement soil physical and chemical properties and sustainable crop yields, Frontiers in Plant Science, 16: 1565081.

https://doi.org/10.3389/fpls.2025.1565081

Choudhary A., Kumar A., Kumar U., Choudhary R., Kumar R., Jat R., Nidhibahen P., Hatamleh A.A., Al-Dosary M.A., Al-Wasel Y.A., Rajagopal R., and Ravindran B., 2022, Various fertilization managements influence the flowering attributes, yield response, biochemical activity and soil nutrient status of chrysanthemum (Chrysanthemum morifolium Ramat.), Sustainability, 14(8): 4561.

https://doi.org/10.3390/su14084561

Dai X., Song D., Zhou W., Liu G., Liang G., He P., Sun G., Yuan F.S., Liu Z., Yao Y., and Cui J., 2021, Partial substitution of chemical nitrogen with organic nitrogen improves rice yield, soil biochemical indictors and microbial composition in a double rice cropping system in south China, Soil and Tillage Research, 205: 104753.

https://doi.org/10.1016/j.still.2020.104753

Diener M., Agostini L., Argento F., Bünemann E.K., Walter A., Mayer J., and Liebisch F., 2026, Linking organic fertilizer properties to in-season N dynamics using multispectral UAV imagery, Precision Agriculture, 27(4): 115.

https://doi.org/10.1007/s11119-026-10414-w

Gouthami B., Gurjar D.S., Brahmanand P.S., Tiwari A.K., Singh M.C., Babu S., Prasad S., Reddy S.B., Alekya M., Rajput J., and Dodewar P.G., 2026, Optimization of irrigation and fertigation interactions for enhanced growth dynamics and floral quality in chrysanthemum (Chrysanthemum morifolium Ramat.) cultivars, Discover Sustainability, 7(1): 884.

https://doi.org/10.1007/s43621-026-03059-2

Guo Y., Zhao C., Liu X., Dong Y., Liu W., Chen Q., Ding S., Zhang J., Guo B., and Gao X., 2025, The impact of organic fertilizer substitution on microbial community structure, greenhouse gas emissions, and enzyme activity in soils with different cultivation durations, Sustainability, 17(10): 4541.

https://doi.org/10.3390/su17104541

Han Y., Ma Z., Chen R., Wen Y., Liang Y.H., Zhang J.Z., Li W.-H., and Wang Z.H., 2025, Organic substitution regulated the soil microbial communities by modifying nutrient limitations in saline-alkaline soils, Agricultural Water Management, 316: 109586.

https://doi.org/10.1016/j.agwat.2025.109586

He H., Peng M.W., Ru S.-B., Hou Z.N., and Li J.H., 2022, A suitable organic fertilizer substitution ratio could improve maize yield and soil fertility with low pollution risk, Frontiers in Plant Science, 13: 988663.

https://doi.org/10.3389/fpls.2022.988663

Hou H.Q., Ji J.H., Lan X.J., Drosos M., Liu X.M., Lv Z.Z., Liu Y.R., Cheng Z., and Zhou W., 2024, Organic fertilizers as partial substitutes for chemical fertilizers enhance nitrogen immobilization and optimize nitrogen fate in paddy soils, Agriculture, 14(12): 2300.

https://doi.org/10.3390/agriculture14122300

Huang C.Y., Zhang K.R., Guo W., Huang H.J., Gou Z., Yang L., Chen Y., Oh K., Fang C., and Luo L., 2023, The effects of partial substitution of fertilizer using different organic materials on soil nutrient condition, aggregate stability and enzyme activity in a tea plantation, Plants, 12(22): 3791.

https://doi.org/10.3390/plants12223791

Jiang F.H., Han S., Cheng W.L., Song L., Tang S., Wang H., Bu R.Y., Li M., Zhu R., Islam M.U., and Wu J., 2026, Soil quality, elemental stoichiometry and crop yield under partial substitution of chemical fertilizers with organic inputs in Vertisols: a six-site field study, Frontiers in Plant Science, 16: 1742932.

https://doi.org/10.3389/fpls.2025.1742932

Li W., Wang K., Feng T., Miao P., Zheng Z.X., Zhang X.C., Zheng W., Li Z., and Zhai B., 2024, Optimizing combination of chemical nitrogen fertilizer and manure can increase yield and economic benefits of dryland wheat while reduce environmental risks, European Journal of Agronomy, 159: 127272.

https://doi.org/10.1016/j.eja.2024.127272

Liu X., Wang C.B., Bai Y.S., Huo L., Wen M.J., and Wang M.C., 2026, Effect of organic fertilizer substitution on soil fertility and yield in a continuous maize cropping system: evidence from an eight-year long-term field experiment, Frontiers in Plant Science, 17: 1824928.

https://doi.org/10.3389/fpls.2026.1824928

Lu W., Hao Z., Ma X., Gao J., Fan X., Guo J., Li J., Lin M., and Zhou Y., 2024, Effects of different proportions of organic fertilizer replacing chemical fertilizer on soil nutrients and fertilizer utilization in gray desert soil, Agronomy, 14(1): 228.

https://doi.org/10.3390/agronomy14010228

Mahjoub D.R., and Allawi M.M., 2022, The effect of bio-fertilizers and bio-stimulants on the growth and flowering of Chrysanthemum morifolium, Biochemical and Cellular Archives, 22(2): 4171.

https://doi.org/10.51470/bca.2022.22.2.4171

Meneghetti L.A.M., Bonfim-Silva E.M., Araújo da Silva T.J., de Oliveira N.P.R., Costa Custódio A.S., Campos e Silva I.A., Bonfim-Silva T.H., da Silva Rocha R.A., Schlichting A.F., Guimarães S.L., Koetz M., de Amorim Teixeira Santos D., dos Santos Guedes P.O.A., and da Silva P.F., 2025, Effects of organic, organomineral, and mineral fertilization on soil macronutrients in chrysanthemum cultivar Singelo cultivation, Horticulturae, 11(6): 567.

https://doi.org/10.3390/horticulturae11060567

Nie M., Gao X., Zhao L.J., Han G., Duan Y., Han R.H., Dong S.Q., Li Y., Du H.L., Yuan X.Y., and Yang Y.J., 2025, Organic substitution enhances soil quality, soil microbial community stability, foxtail millet productivity, and grain quality in North China, Journal of Environmental Management, 384: 125613.

https://doi.org/10.1016/j.jenvman.2025.125613

Pahalvi H.N., Rafiya L., Rashid S., Nisar B., and Kamili A.N., 2021, Chemical fertilizers and their impact on soil health, Microbiota and Biofertilizers, 2021: 1-20.

https://doi.org/10.1007/978-3-030-61010-4_1

Pan X., Yu H.J., Zhang B., Guan Y., Zhang N., Du H.L., Liu F.M., Yu J., Wang Q., and Liu J., 2025, Effects of organic fertilizer replacement on the microbial community structure in the rhizosphere soil of soybeans in albic soil, Scientific Reports, 15(1): 12271.

https://doi.org/10.1038/s41598-025-96463-z

Pansuriya B.J., and Kumari K., 2024, Effect of liquid organic inputs on growth, flowering and yield of chrysanthemum (Chrysanthemum morifolium Ramat.) and soil properties, Asian Journal of Soil Science and Plant Nutrition, 10(3): 319-326.

https://doi.org/10.9734/ajsspn/2024/v10i3343

Ren J.H., Liu X.L., Yang W.-P., Yang X., Li W., Xia Q., Li J., Gao Z.Q., and Yang Z., 2021, Rhizosphere soil properties, microbial community, and enzyme activities: short-term responses to partial substitution of chemical fertilizer with organic manure, Journal of Environmental Management, 299: 113650.

https://doi.org/10.1016/j.jenvman.2021.113650

Son S., Hoagland L., Deering A., Wei-Kocsis J., and Nemali K., 2026, Nutrient release and yield comparison between customized organic and conventional fertilizers in hydroponic lettuce production, Frontiers in Plant Science, 17: 1785126.

https://doi.org/10.3389/fpls.2026.1785126

Sun C., Zheng H., He S.X., Zhao Q., Liu Y., and Liu H., 2024, Partial substitution of chemical fertilizer by organic fertilizer increases yield, quality and nitrogen utilization of Dioscorea polystachya, PLOS ONE, 19(4): e0301108.

https://doi.org/10.1371/journal.pone.0301108

Tang C., Du S.-P., Ma Z.M., Xue L., Chen J., and Hai L., 2024, Effects of the replacement of chemical fertilizers with organic fertilizers in different proportions on microbial biomass and enzyme activities of soil aggregates in gravel-mulched field, Sustainability, 16(6): 2483.

https://doi.org/10.3390/su16062483

Tyagi J., Ahmad S., and Malik M., 2022, Nitrogenous fertilizers: impact on environment sustainability, mitigation strategies, and challenges, International Journal of Environmental Science and Technology, 19(11): 11649-11672.

https://doi.org/10.1007/s13762-022-04027-9

Wang B., Wang S., Li G., Fu L., Chen H., Yin M., and Chen J.F., 2025, Reducing nitrogen fertilizer usage coupled with organic substitution improves soil quality and boosts tea yield and quality in tea plantations, Journal of the Science of Food and Agriculture, 105(2): 1228-1238.

https://doi.org/10.1002/jsfa.13913

Wei J., Yang S., Wang X., Duan J., Mei T., Li M., Yang S., and Wang F., 2025, Effects of organic fertilizer replacing chemical fertilizer on organic carbon mineralization and active carbon fractions in yellow paddy soil of Guizhou Province, PLOS ONE, 20(5): e0323801.

https://doi.org/10.1371/journal.pone.0323801

Xu W., Liu W.J., Tang S., Yang Q., Meng L., Wu Y.Z., Wang J., Wu L., Wu M., Xue X.X., Wang W.B., and Luo W., 2023, Long-term partial substitution of chemical nitrogen fertilizer with organic fertilizers increased SOC stability by mediating soil C mineralization and enzyme activities in a rubber plantation of Hainan Island, China, Applied Soil Ecology, 182: 104691.

https://doi.org/10.1016/j.apsoil.2022.104691