Does the incorporation of dicyandiamide and hydroquinone with straw enhance the nitrogen supplying capacity in soil?

doi:10.1016/j.apsoil.2018.12.007

Applied Soil Ecology

Volume 136, April 2019, Pages 158-162

https://doi.org/10.1016/j.apsoil.2018.12.007 Get rights and content

Highlights

•
Effects of fixed NH₄⁺ on N conservation and supply were greater than that of SMBN.
•
Inhibitors regulated SMBN mineralization and fixed NH₄⁺ release, especially DCD.
•
Inhibitors increased crop yield in the absence of straw, which decreased crop yield.
•
The combination of DCD and straw further decreased N availability and crop yield.
•
Addition of HQ alleviated the decline of N availability caused by straw application.

Abstract

We conducted a pot experiment with spring wheat to examine the effects of microbial immobilization/mineralization and soil mineral fixation/defixation on nitrogen (N) conservation and supply and determine the influences of inhibitors and straw additions on these processes. Results showed that the effects of fixed NH₄⁺ pool on N conservation and supply were 3.1- and 2.2-fold, respectively, of the effects of soil microbial biomass N (SMBN) pool in the treatments without straw and 1.3- and 1.4-fold, respectively, of the effects of the SMBN pool in the treatments with straw application. In the absence of straw, the nitrification inhibitor (dicyandiamide, DCD) and urease inhibitor (hydroquinone, HQ) improved crop yield. Conversely, crop yield declined when straw was used especially in combination with DCD. Meanwhile, HQ alleviated the decrease in crop yield induced by straw application. These phenomena were attributed to the fact that DCD coupled with straw further enhances microbial immobilization and decreases N availability. HQ delayed the hydrolysis of urea, asynchronizing the microbial immobilization and NH₄⁺supply and consequently mitigating the decline in N availability. Both inhibitors regulated the fixed NH₄⁺ release, especially the DCD. In general, DCD tends to conserve N in soil and lowers N availability, whereas HQ is favorable for the maintenance of N in mineral forms and increasing its availability.

Introduction

Soil microorganism is the primary driving agent of nitrogen (N) cycling and an important N sink and source for crops (Nannipieri and Paul, 2009). To regulate N cycling, many researchers improve microbial activity by adding organic materials (Chen et al., 2014). The fixation and defixation of ammonium by soil clay minerals are also important processes for N cycling in soils, especially in 2:1 clay minerals (Nieder et al., 2011). More than 70% of applied fertilizer N can be fixed in some types of soil, and over 80% of recently fixed NH₄⁺ can be released after several weeks or during growing seasons (Ahmad et al., 1982, Matsuoka and Moritsuka, 2011). However, less attention has been given to the comparison between the effects of soil microbial biomass N (SMBN) pool on N conservation and supply and those of fixed NH₄⁺ pool.

For the amelioration of N use efficiency (NUE) and mitigation of environmental pollution, fertilizer N transformation processes in soil are usually regulated with inhibitors (Abalos et al., 2014), which alter the form of fertilizer N by retarding ammonium oxidation (nitrification inhibitors) or urea hydrolysis (urease inhibitors). The cationic form of fertilizer N can be enhanced and retained through inhibitor additions, which is the preferred source of N for microorganisms (Jansson, 1958) and can be fixed by soil clay minerals (Nieder et al., 2011). Kaye and Hart (1997) inferred that the competition for NH₄⁺ exists between microbial activity (immobilization or nitrificaton) and mineral fixation processes. Microbial activity is also a primary driving force of fixed NH₄⁺ release, and NH₄⁺ derived from organic N mineralization can be fixed by clay minerals (Nieder et al., 2011, Ma et al., 2015). Therefore, the relationship between SMBN and fixed NH₄⁺ pools should be clarified for the assessment of N availability and optimization of N management.

In the present study, a pot experiment was carried out with inhibitors and straw additions. The objectives were as follows: (i) to elucidate the synergistic effects of nitrification inhibitor (dicyandiamide, DCD), urease inhibitor (hydroquinone, HQ), and straw on N transformation; (ii) to compare the contributions of the SMBN and fixed NH₄⁺ pools to N supply; and (iii) to identify the effects on crop yield.

Section snippets

Experimental site, design, and treatments

Test soil (0–10 cm) without fertilization since 1990 was collected from a long-term experiment in Shenyang Experimental Station, Chinese Academy of Sciences. The study area and the test soil properties were described in detail by Ma et al. (2015).

The pot experiment was conducted with spring wheat (Triticum aestivum L.) from April 6 to July 4, 2013 in a net house, which was furnished with a rainproof shelter. Nine treatments were performed, namely, (1) control (CK), (2) urea (U), (3)

Result

Soil mineral N (NH₄⁺-N plus NO₃⁻-N) was significantly influenced by the inhibitors and straw additions (Fig. 1a, b). In the absence of straw, the NH₄⁺-N levels in the treatments that received DCD remained high relative to that in the U treatment. The SMBN and fixed NH₄⁺ increased respectively by 4.0 mg kg⁻¹ (25.5%) and 15.7 mg kg⁻¹ (7.4%) in the DCD treatment and 6.2 mg kg⁻¹ (39.3%) and 4.1 mg kg⁻¹ (1.9%) in the DCD + HQ treatment, compared with the U treatment (Fig. 1c, d). However, the peaks

Discussion

Nitrogen was immobilized in the present study by microorganism approximately equal to 16.4% of the applied fertilizer N in the treatments without straw. Both inhibitors raised the average level of SMBN, especially when DCD was coupled with HQ. Xu et al. (2001) obtained parallel result and pointed out that inhibitors, particularly DCD, prolong the presence of NH₄⁺, facilitating microbial immobilization (Jansson, 1958). When straw was applied, SMBN significantly increased, accounting for 39.0% of

Conclusion

In the absence of straw, inhibitor addition increased N supplying capacity in soil and crop yield. The most evident increase was observed when both HQ and DCD were used. The addition of straw, along with DCD, significantly decreased N supply in current season and crop yield. The decreases were attributed to drastic microbial immobilization and subsequent slow remineralization, which weakened the synchrony of the N supply with crop demand. However, urease inhibitor can be utilized for the

Acknowledgements

This work was financially supported by the National Natural Science Foundation of China (grant numbers 41471250, 41877106, 41877107), National Key Technology R&D Program (grant number 2015BAD05B01), and Doctoral Research Fund of Liaoning Province, China (grant number 20180540071).

References (22)

D. Abalos et al.
Meta-analysis of the effect of urease and nitrification inhibitors on crop productivity and nitrogen use efficiency
Agric. Ecosyst. Environ.
(2014)
P.C. Brookes et al.
Chloroform fumigation and the release of soil nitrogen: a rapid direct extraction method to measure microbial biomass nitrogen in soil
Soil Biol. Biochem.
(1985)
J.P. Kaye et al.
Competition for nitrogen between plants and soil microorganisms
Trends Ecol. Evol.
(1997)
Q. Ma et al.
Responses of biotic and abiotic effects on conservation and supply of fertilizer N to inhibitors and glucose inputs
Soil Biol. Biochem.
(2015)
P. Nannipieri et al.
The chemical and functional characterization of soil N and its biotic components
Soil Biol. Biochem.
(2009)
F.F. Pan et al.
Do organic amendments improve the synchronism between soil N supply and wheat demand?
Appl. Soil. Ecol.
(2018)
S.M. Shen et al.
Mineralization and immobilization of nitrogen in fumigated soil and the measurement of microbial biomass nitrogen
Soil Biol. Biochem.
(1984)
W. Yu et al.
Alterations of pathways in fertilizer N conservation and supply in soils treated with dicyandiamide, hydroquinone and glucose
Appl. Soil. Ecol.
(2016)
N. Ahmad et al.
Crop utilization and fixation of added ammonium in soils of the West Indies
Plant Soil
(1982)
B. Chen et al.
Soil nitrogen dynamics and crop residues. A review
Agron. Sustain. Dev.
(2014)

S.L. Jansson

Tracer studies on nitrogen transformations in soil with special attention to mineralization-immobilization relationships

Ann. R. Agric. College Sweden

(1958)

Cited by (9)

Reaching food security: harnessing urease inhibitors to meet the challenges of growing global population
2024, Ureases
Food security is challenging considering the expectations of a world population of over 9 billion people by 2050. Urease inhibitors as additives in urea-based fertilizer formulations may comprise a strategy to increase food supply in the coming years. When applied to soil, the worldwide used nitrogen fertilizer urea is rapidly converted to ammonia and carbon dioxide by the action of extracellular soil ureases. Such a reaction on the soil surface results in N losses to the atmosphere due to the gaseous nature of ammonia. The N-(butyl)thiophosphoric triamide (NBPT), a well-known competitive urease inhibitor, has been widely investigated in the field with respect to its ability to overcome N losses and improve urea efficiency in the soil. However, the window-narrowed effect of NBPT as a urease inhibitor and the shelf life of NBPT-containing urea formulations require further investigations aiming for improvements in the NBPT action and/or the search for other substances with increased effectiveness regarding the inhibition of soil ureases. This chapter presents the current knowledge on the use of NBPT in the field to boost crop production. The findings obtained using other urease inhibitors and biological matrices are also discussed.
Straw amendment and nitrification inhibitor controlling N losses and immobilization in a soil cooling-warming experiment
2023, Science of the Total Environment
It is common practice in agriculture to apply high‑carbon amendments, e.g. straw, or nitrification inhibitors (NI) to reduce soil nitrogen (N) losses. However, little is known on the combined effects of straw and NI and how seasonal soil temperature variations further affect N immobilization. We conducted a 113-day mesocosm experiment with different levels of ¹⁵N-fertilizer application (N0: control; N1: 125 kg N ha⁻¹; N2: 250 kg N ha⁻¹) in an agricultural soil, amended with either wheat straw, NI or a combination of both in order to investigate N retention and loss from soil after a cooling-warming phase simulating a seasonal temperature shift, i.e., 30 days cooling phase at 7 °C and 10 days warming phase at 21 °C. Subsequently, soils were planted with barley as phytometers to study ¹⁵N-transfer to a following crop.
Straw addition significantly reduced soil N-losses due to microbial N immobilization. Although carbon added as straw led to increased N₂O emissions at high N fertilization, this was partly counterbalanced by NI. Soil cooling-warming strongly increased ammonification (+77 %), while nitrification was suppressed, and straw-induced microbial N immobilization dominated. N immobilized after straw addition was mineralized at the end of the experiment as indicated by structural equation models. Re-mineralization in N2 was sufficient, but still suboptimal in N0 and N1 at critical times of early barley growth. N-use efficiency of the ¹⁵N tracer decreased with fertilization intensity from 50 % in N1 to 35 % in N2, and straw amendment reduced NUE to 25 % at both fertilization rates. Straw amendment was most powerful in reducing N-losses (−41 %), in particular under variable soil temperature conditions, but NI enforced its effects by reducing N₂O emission (−40 %) in N2 treatment. Sufficient N-fertilization coupled with straw application is required to adjust the timely re-mineralization of N for subsequent crops.
Enhanced-Efficiency Nitrogen Fertilizers Coated with Sulfur, Inhibitor, and Epoxy Resin: Preparation and Effects on Maize Growth and Nitrogen Utilization
2023, Journal of Soil Science and Plant Nutrition
Nitrate Supply Affects Copper Nanoparticle Accumulation by Maize Plant and Availability of Nutrients in Rhizosphere and Bulk Soil
2022, Journal of Soil Science and Plant Nutrition
Effects of combined nitrification inhibitors on soil nitrification, maize yield and nitrogen use efficiency in three agricultural soils
2022, PLoS ONE
Effects of Combined Nitrification Inhibitors on Nitrogen Transformation, Maize Yield and Nitrogen Uptake in Two Different Soils
2022, Communications in Soil Science and Plant Analysis

View all citing articles on Scopus

View full text

Short communicationDoes the incorporation of dicyandiamide and hydroquinone with straw enhance the nitrogen supplying capacity in soil?

Highlights

Abstract

Introduction

Section snippets

Experimental site, design, and treatments

Result

Discussion

Conclusion

Acknowledgements

Agric. Ecosyst. Environ.

Soil Biol. Biochem.

Trends Ecol. Evol.

Soil Biol. Biochem.

Soil Biol. Biochem.

Appl. Soil. Ecol.

Soil Biol. Biochem.

Appl. Soil. Ecol.

Crop utilization and fixation of added ammonium in soils of the West Indies

Plant Soil

Soil nitrogen dynamics and crop residues. A review

Agron. Sustain. Dev.

Tracer studies on nitrogen transformations in soil with special attention to mineralization-immobilization relationships

Ann. R. Agric. College Sweden

Short communication
Does the incorporation of dicyandiamide and hydroquinone with straw enhance the nitrogen supplying capacity in soil?