Dataset Information

Long-term N fertilization reduces uptake of N from fertilizer and increases the uptake of N from soil.

ABSTRACT: Long-term supply of synthetic nitrogen (N) has the potential to affect the soil N processes. This study aimed to (i) establish N response curves to find the best balance between inputs and outputs of N over four ratoons; (ii) use ¹⁵N-labeled fertilizer to estimate the N recovery efficiency of fertilizer applied in the current season as affected by the N management in the previous three years. Nitrogen rates (control, 60, 120, and 180 kg ha^-1 N) were applied annually in the same plots after the 1st, 2nd, 3rd, and 4th sugarcane cycles. Sugarcane yield, N uptake, and N balance were evaluated. In the final season, 100 kg ha^-1 of ¹⁵N was also applied in the microplots to evaluate the effect of previous N fertilization on N derived from fertilizer (NDF) and N derived from soil (NDS). Sugarcane yields increased linearly with the N rates over the four sugarcane-cycles. The best balance between the input of N through fertilizer and N removal by stalks was 90 kg ha^-1 N in both the 1st and 2nd ratoons, and 71 kg ha^-1 N in both the 3rd and 4th ratoons. Long-term application of N reduced NDF from 41 to 30 kg ha^-1 and increased NDS from 160 to 180 kg ha^-1 N. A key finding is that long-term N fertilization has the potential to affect soil N processes by increasing the contribution of soil N and reducing the contribution of N from fertilizer.

SUBMITTER: Joris HAW

PROVIDER: S-EPMC7606474 | biostudies-literature | 2020 Nov

REPOSITORIES: biostudies-literature

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Long-term N fertilization reduces uptake of N from fertilizer and increases the uptake of N from soil.

Joris Helio Antonio Wood HAW Vitti André Cesar AC Ferraz-Almeida Risely R Otto Rafael R Cantarella Heitor H

Scientific reports 20201102 1

Long-term supply of synthetic nitrogen (N) has the potential to affect the soil N processes. This study aimed to (i) establish N response curves to find the best balance between inputs and outputs of N over four ratoons; (ii) use <sup>15</sup>N-labeled fertilizer to estimate the N recovery efficiency of fertilizer applied in the current season as affected by the N management in the previous three years. Nitrogen rates (control, 60, 120, and 180 kg ha<sup>-1</sup> N) were applied annually in the ...[more]

PMID: 33139850

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Dataset Information

Long-term N fertilization reduces uptake of N from fertilizer and increases the uptake of N from soil.

Publications

Long-term N fertilization reduces uptake of N from fertilizer and increases the uptake of N from soil.

Similar Datasets

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