Abstract
To clarify how nitrogen (N) and water regulate the microbe mediated carbon (C) cycle in farmland, a 3-year experiment was conducted in a wheat–maize rotation at Jiaozhou Station, North China. Twelve treatments combined four drip irrigation regimes (T1: no irrigation; T2: 40 mm irrigation at flowering; T3: 40 mm irrigation at the grain filling stage; T4: both, 40 mm each) and three N levels (N0: 0 kgN·hm−2; N1: 92 kgN·hm−2; N2: 184 kgN·hm−2). In this study, we measured wheat yield and biomass, soil organic carbon and nitrogen content, soil respiration, soil microbial community, and C-metabolic genes. The results showed that wheat yield increased with N, peaking at 8949.81 kg·hm−2 in the N2T3 treatment, while irrigation had no significant independent effect on yield but interacted with nitrogen fertilization: under identical nitrogen levels (N1, N2), yields in the T1 and T2 treatments were significantly lower than those in the T3/T4 treatments. The soil organic carbon content in N2 was significantly higher; the soil C/N ratio was highest in N2, and T3 resulted in a significantly higher C/N ratio than T1 under the same N level; total soil respiration in N0 was significant lower, and T4 had higher respiration than T2 under the same N level. N addition increased Actinobacteriota, Chloroflexi, Gemmatimonadetes, and Ascomycota, while decreaing Proteobacteria and Acidobacteriota. No reduction in fungal phylum was observed with nitrogen addition. N application significantly upregulated key enzymes in the pentose phosphate pathway (e.g., transketolase K00615, transaldolase K00616), while irrigation increased phosphoserine aminotransferase (K00831) abundance and decreased methylmalonyl-CoA mutase (K01848) abundance. N2T3 maintains high SOC content while achieving maximum yield, promoting soil fertility retention. Compared to T4, N2T3 also enhances water use efficiency. The N2T3 treatment (high N and grain filling stage irrigation) achieved the optimal balance between high wheat yield and SOC sequestration.
Abstract from the paper’s OpenAlex record; open copy licensed cc-by. Read at the source ↗
The text the model read, with the source record’s inline markup (italics, sub- and superscripts) rendered and its character entities decoded; quote offsets refer to the raw text.
Claims 18
Claim · model-written summary
Wheat yield increased with nitrogen.
- Taxon
- wheat
Triticum aestivume0 - Treatment
- Ne0
- Outcome
- wheat yielde0
- Direction
- increasede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The results showed that wheat yield increased with N, peaking at 8949.81 kg·hm−2 in the N2T3 treatment, while irrigation had no significant independent effect on yield but interacted with nitrogen fertilization: under identical nitrogen levels (N1, N2), yields in the T1 and T2 treatments were significantly lower than those in the T3/T4 treatments.”
Claim · model-written summary
Wheat yield peaked at 8949.81 kg·hm−2 under N2T3.
- Taxon
- wheatTriticum aestivume0
- Treatment
- N2T3e0
- Outcome
- wheat yielde0
- Direction
- peakinge0
- Value
- 8949.81 kg·hm−2e0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The results showed that wheat yield increased with N, peaking at 8949.81 kg·hm−2 in the N2T3 treatment, while irrigation had no significant independent effect on yield but interacted with nitrogen fertilization: under identical nitrogen levels (N1, N2), yields in the T1 and T2 treatments were significantly lower than those in the T3/T4 treatments.”
Claim · model-written summary
Irrigation alone had no significant effect on wheat yield.
- Taxon
- wheatTriticum aestivume0
- Treatment
- irrigatione0
- Outcome
- yielde0
- Direction
- no significant independent effecte0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The results showed that wheat yield increased with N, peaking at 8949.81 kg·hm−2 in the N2T3 treatment, while irrigation had no significant independent effect on yield but interacted with nitrogen fertilization: under identical nitrogen levels (N1, N2), yields in the T1 and T2 treatments were significantly lower than those in the T3/T4 treatments.”
Claim · model-written summary
At equal nitrogen rates T1 and T2 yielded less than T3 and T4.
- Taxon
- wheatTriticum aestivume0
- Treatment
- T1 and T2 treatmentse0
- Outcome
- yieldse0
- Direction
- lowere0
- Qualifier
- under identical nitrogen levels (N1, N2)e0
- Comparator
- T3/T4 treatmentse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The results showed that wheat yield increased with N, peaking at 8949.81 kg·hm−2 in the N2T3 treatment, while irrigation had no significant independent effect on yield but interacted with nitrogen fertilization: under identical nitrogen levels (N1, N2), yields in the T1 and T2 treatments were significantly lower than those in the T3/T4 treatments.”
Claim · model-written summary
Soil organic carbon was higher under N2.
- Taxon
- wheatTriticum aestivumt0
- Treatment
- N2e0
- Outcome
- soil organic carbon contente0
- Direction
- highere0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The soil organic carbon content in N2 was significantly higher; the soil C/N ratio was highest in N2, and T3 resulted in a significantly higher C/N ratio than T1 under the same N level; total soil respiration in N0 was significant lower, and T4 had higher respiration than T2 under the same N level.”
t0“Wheat Fields”
Claim · model-written summary
Soil C/N was highest under N2.
- Taxon
- wheatTriticum aestivumt0
- Treatment
- N2e0
- Outcome
- soil C/N ratioe0
- Direction
- higheste0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The soil organic carbon content in N2 was significantly higher; the soil C/N ratio was highest in N2, and T3 resulted in a significantly higher C/N ratio than T1 under the same N level; total soil respiration in N0 was significant lower, and T4 had higher respiration than T2 under the same N level.”
t0“Wheat Fields”
Claim · model-written summary
T3 increased soil C/N over T1 at equal nitrogen.
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The soil organic carbon content in N2 was significantly higher; the soil C/N ratio was highest in N2, and T3 resulted in a significantly higher C/N ratio than T1 under the same N level; total soil respiration in N0 was significant lower, and T4 had higher respiration than T2 under the same N level.”
t0“Wheat Fields”
Claim · model-written summary
Soil respiration was lower under N0.
- Taxon
- wheatTriticum aestivumt0
- Treatment
- N0e0
- Outcome
- total soil respiratione0
- Direction
- lowere0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The soil organic carbon content in N2 was significantly higher; the soil C/N ratio was highest in N2, and T3 resulted in a significantly higher C/N ratio than T1 under the same N level; total soil respiration in N0 was significant lower, and T4 had higher respiration than T2 under the same N level.”
t0“Wheat Fields”
Claim · model-written summary
T4 raised soil respiration over T2 at equal nitrogen.
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The soil organic carbon content in N2 was significantly higher; the soil C/N ratio was highest in N2, and T3 resulted in a significantly higher C/N ratio than T1 under the same N level; total soil respiration in N0 was significant lower, and T4 had higher respiration than T2 under the same N level.”
t0“Wheat Fields”
Claim · model-written summary
Nitrogen addition increased four soil microbial groups.
- Taxon
- WheatTriticum aestivumt0
- Treatment
- N additione0
- Outcome
- Actinobacteriota, Chloroflexi, Gemmatimonadetes, and Ascomycotae0
- Direction
- increasede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“N addition increased Actinobacteriota, Chloroflexi, Gemmatimonadetes, and Ascomycota, while decreaing Proteobacteria and Acidobacteriota. No reduction in fungal phylum was observed with nitrogen addition.”
t0“Wheat Fields”
Claim · model-written summary
Nitrogen addition decreased Proteobacteria and Acidobacteriota.
- Taxon
- WheatTriticum aestivumt0
- Treatment
- N additione0
- Outcome
- Proteobacteria and Acidobacteriotae0
- Direction
- decreainge0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“N addition increased Actinobacteriota, Chloroflexi, Gemmatimonadetes, and Ascomycota, while decreaing Proteobacteria and Acidobacteriota. No reduction in fungal phylum was observed with nitrogen addition.”
t0“Wheat Fields”
Claim · model-written summary
Nitrogen addition did not reduce fungal phyla.
- Taxon
- WheatTriticum aestivumt0
- Treatment
- nitrogen additione0
- Outcome
- fungal phylume0
- Direction
- No reductione0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“N addition increased Actinobacteriota, Chloroflexi, Gemmatimonadetes, and Ascomycota, while decreaing Proteobacteria and Acidobacteriota. No reduction in fungal phylum was observed with nitrogen addition.”
t0“Wheat Fields”
Claim · model-written summary
Nitrogen upregulated pentose phosphate pathway enzymes.
- Taxon
- WheatTriticum aestivumt0
- Treatment
- N applicatione0
- Gene
- transketolase K00615e0
- Outcome
- key enzymes in the pentose phosphate pathwaye0
- Direction
- upregulatede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“N application significantly upregulated key enzymes in the pentose phosphate pathway (e.g., transketolase K00615, transaldolase K00616), while irrigation increased phosphoserine aminotransferase (K00831) abundance and decreased methylmalonyl-CoA mutase (K01848) abundance.”
t0“Wheat Fields”
Claim · model-written summary
Irrigation increased phosphoserine aminotransferase abundance.
- Taxon
- WheatTriticum aestivumt0
- Treatment
- irrigatione0
- Gene
- phosphoserine aminotransferase (K00831)e0
- Outcome
- phosphoserine aminotransferase (K00831) abundancee0
- Direction
- increasede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“N application significantly upregulated key enzymes in the pentose phosphate pathway (e.g., transketolase K00615, transaldolase K00616), while irrigation increased phosphoserine aminotransferase (K00831) abundance and decreased methylmalonyl-CoA mutase (K01848) abundance.”
t0“Wheat Fields”
Claim · model-written summary
Irrigation decreased methylmalonyl-CoA mutase abundance.
- Taxon
- WheatTriticum aestivumt0
- Treatment
- irrigatione0
- Gene
- methylmalonyl-CoA mutase (K01848)e0
- Outcome
- methylmalonyl-CoA mutase (K01848) abundancee0
- Direction
- decreasede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“N application significantly upregulated key enzymes in the pentose phosphate pathway (e.g., transketolase K00615, transaldolase K00616), while irrigation increased phosphoserine aminotransferase (K00831) abundance and decreased methylmalonyl-CoA mutase (K01848) abundance.”
t0“Wheat Fields”
Claim · model-written summary
N2T3 maintained high soil carbon while attaining maximum wheat yield.
- Taxon
- WheatTriticum aestivumt0
- Treatment
- N2T3e0
- Outcome
- maximum yielde0
- Direction
- maximume0
- Qualifier
- high SOC contente0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“N2T3 maintains high SOC content while achieving maximum yield, promoting soil fertility retention. Compared to T4, N2T3 also enhances water use efficiency. The N2T3 treatment (high N and grain filling stage irrigation) achieved the optimal balance between high wheat yield and SOC sequestration.”
t0“Wheat Fields”
Claim · model-written summary
N2T3 improved water use efficiency relative to T4.
- Taxon
- WheatTriticum aestivumt0
- Treatment
- N2T3e0
- Outcome
- water use efficiencye0
- Direction
- enhancese0
- Comparator
- T4e0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“N2T3 maintains high SOC content while achieving maximum yield, promoting soil fertility retention. Compared to T4, N2T3 also enhances water use efficiency. The N2T3 treatment (high N and grain filling stage irrigation) achieved the optimal balance between high wheat yield and SOC sequestration.”
t0“Wheat Fields”
Claim · model-written summary
The authors identify N2T3 as the best balance of yield and soil carbon sequestration.
- Taxon
- WheatTriticum aestivumt0
- Treatment
- N2T3 treatmente0
- Outcome
- optimal balance between high wheat yield and SOC sequestratione0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“N2T3 maintains high SOC content while achieving maximum yield, promoting soil fertility retention. Compared to T4, N2T3 also enhances water use efficiency. The N2T3 treatment (high N and grain filling stage irrigation) achieved the optimal balance between high wheat yield and SOC sequestration.”
t0“Wheat Fields”
The same questions in other papers
irrigation · yield · Triticum aestivum (wheat)Positive and negative results
190 papers in the same direction as this paper · 798 in the opposite direction
- positive
- positive
- positive
985 papers more in this group
See all 989 papers →nitrogen · yield · Triticum aestivum (wheat)Positive and negative results
1,736 papers in the same direction as this paper · 285 in the opposite direction · 39 reporting no difference from an alternative
- negative
- negative
- negative
2,057 papers more in this group
See all 2,061 papers →Claims are grouped by organism, treatment and what was measured or targeted. A paper counts as positive when any of its claims in the group is positive.