Abstract
Introduction Straw return combined with rational nitrogen (N) fertilization plays a critical role in coordinating the transformation of soil organic carbon and nitrogen availability, thereby improving nitrogen use efficiency (NUE), crop yield, and soil fertility. However, the dynamics of soil carbon and nitrogen fractions under straw return with varying N inputs, and their specific contributions to NUE and yield, remain unclear. Methods A three-year split-plot field experiment was conducted in the Tumochuan Plain Irrigation District. The main plots included deep plowing with straw return (DPR) and no straw return (RT), while subplots comprised four N application rates (0, 210, 255, and 300 kg ha -1 ). Soil carbon and nitrogen fractions, maize yield, NUE, and partial factor productivity of nitrogen (PFPN) were assessed. Results Compared to RT, DPR significantly improved soil nutrient levels and labile C and N fractions in the 0–40 cm soil layer. Maize yield, NUE, and PFPN increased by 17.28%, 18.24%, and 17.88%, respectively. Under DPR, a linear-plus-plateau model estimated the optimal N rate at 237.3 kg ha -1 , reducing N input by 20.89% without compromising performance. Key contributors to NUE and PFPN included mineral nitrogen (MN), soil quality index (SQI), and dry matter accumulation (DMA), with relative contributions of 9.39%, 8.96%, and 8.49% to NUE, and 9.31%, 9.18%, and 8.99% to PFPN, respectively. Discussion Straw return enhanced soil nitrogen availability and maize productivity by improving MN and SQI. Even with a 15–20% reduction in N application, DPR sustained high soil C and N fractions, yield, and NUE. These results offer practical guidance for optimizing N management under long-term straw return, with significant implications for sustainable maize production and soil fertility enhancement.
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 14
Claim · model-written summary
Deep plowing with straw return significantly improved soil nutrient levels and labile carbon and nitrogen fractions over no straw return.
- Treatment
- deep plowing with straw returne1
- Outcome
- soil nutrient levels and labile C and N fractionse0
- Direction
- improvede0
- Qualifier
- 0–40 cm soil layere0
- Comparator
- no straw returne1
Zea maysOrganisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Compared to RT, DPR significantly improved soil nutrient levels and labile C and N fractions in the 0–40 cm soil layer.”
e1“deep plowing with straw return (DPR) and no straw return (RT)”
t0“maize”
Claim · model-written summary
DPR increased maize yield by 17.28% over no straw return.
- Treatment
- deep plowing with straw returne1
- Outcome
- yielde0
- Direction
- increasede0
- Value
- 17.28%e0
- Comparator
- no straw returne1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Maize yield, NUE, and PFPN increased by 17.28%, 18.24%, and 17.88%, respectively.”
e1“deep plowing with straw return (DPR) and no straw return (RT)”
Claim · model-written summary
DPR increased maize nitrogen use efficiency by 18.24%.
- Treatment
- deep plowing with straw returne1
- Outcome
- NUEe0
- Direction
- increasede0
- Value
- 18.24%e0
- Comparator
- no straw returne1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Maize yield, NUE, and PFPN increased by 17.28%, 18.24%, and 17.88%, respectively.”
e1“deep plowing with straw return (DPR) and no straw return (RT)”
Claim · model-written summary
DPR increased maize partial factor productivity of nitrogen by 17.88%.
- Treatment
- deep plowing with straw returne1
- Outcome
- PFPNe0
- Direction
- increasede0
- Value
- 17.88%e0
- Comparator
- no straw returne1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Maize yield, NUE, and PFPN increased by 17.28%, 18.24%, and 17.88%, respectively.”
e1“deep plowing with straw return (DPR) and no straw return (RT)”
Claim · model-written summary
A model estimated the optimal nitrogen rate under DPR at 237.3 kg ha -1.
Verbatim
e0“Under DPR, a linear-plus-plateau model estimated the optimal N rate at 237.3 kg ha -1 , reducing N input by 20.89% without compromising performance.”
Claim · model-written summary
The estimated optimal rate reduced nitrogen input by 20.89% without compromising performance.
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“reducing N input by 20.89% without compromising performance.”
t0“maize”
Claim · model-written summary
Mineral nitrogen contributed 9.39% to NUE.
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Key contributors to NUE and PFPN included mineral nitrogen (MN), soil quality index (SQI), and dry matter accumulation (DMA), with relative contributions of 9.39%, 8.96%, and 8.49% to NUE, and 9.31%, 9.18%, and 8.99% to PFPN, respectively.”
t0“maize”
Claim · model-written summary
Soil quality index contributed 8.96% to NUE.
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Key contributors to NUE and PFPN included mineral nitrogen (MN), soil quality index (SQI), and dry matter accumulation (DMA), with relative contributions of 9.39%, 8.96%, and 8.49% to NUE, and 9.31%, 9.18%, and 8.99% to PFPN, respectively.”
t0“maize”
Claim · model-written summary
Dry matter accumulation contributed 8.49% to NUE.
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Key contributors to NUE and PFPN included mineral nitrogen (MN), soil quality index (SQI), and dry matter accumulation (DMA), with relative contributions of 9.39%, 8.96%, and 8.49% to NUE, and 9.31%, 9.18%, and 8.99% to PFPN, respectively.”
t0“maize”
Claim · model-written summary
Mineral nitrogen contributed 9.31% to PFPN.
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Key contributors to NUE and PFPN included mineral nitrogen (MN), soil quality index (SQI), and dry matter accumulation (DMA), with relative contributions of 9.39%, 8.96%, and 8.49% to NUE, and 9.31%, 9.18%, and 8.99% to PFPN, respectively.”
t0“maize”
Claim · model-written summary
Soil quality index contributed 9.18% to PFPN.
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Key contributors to NUE and PFPN included mineral nitrogen (MN), soil quality index (SQI), and dry matter accumulation (DMA), with relative contributions of 9.39%, 8.96%, and 8.49% to NUE, and 9.31%, 9.18%, and 8.99% to PFPN, respectively.”
t0“maize”
Claim · model-written summary
Dry matter accumulation contributed 8.99% to PFPN.
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Key contributors to NUE and PFPN included mineral nitrogen (MN), soil quality index (SQI), and dry matter accumulation (DMA), with relative contributions of 9.39%, 8.96%, and 8.49% to NUE, and 9.31%, 9.18%, and 8.99% to PFPN, respectively.”
t0“maize”
Claim · model-written summary
Straw return improved soil nitrogen availability and maize productivity through mineral nitrogen and soil quality index.
- Treatment
- Straw returne0
- Outcome
- soil nitrogen availability and maize productivitye0
- Qualifier
- improving MN and SQIe0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Straw return enhanced soil nitrogen availability and maize productivity by improving MN and SQI.”
Claim · model-written summary
DPR maintained soil C and N fractions, yield and NUE despite 15–20% less nitrogen.
- Treatment
- 15–20% reduction in N applicatione0
- Outcome
- soil C and N fractions, yield, and NUEe0
- Direction
- sustained highe0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Even with a 15–20% reduction in N application, DPR sustained high soil C and N fractions, yield, and NUE.”
t0“maize”
The same questions in other papers
organic · nutrient: efficiency · Zea mays (maize)Positive and negative results
13 papers in the same direction as this paper · 2 in the opposite direction
- no effect
- negative
- positive
12 papers more in this group
See all 16 papers →tillage · nutrient: efficiency · Zea mays (maize)Positive and negative results
18 papers in the same direction as this paper · 1 in the opposite direction · 1 reporting no difference from an alternative
- negative
- no effect
- positive
17 papers more in this group
See all 21 papers →organic · nutrient: content · Zea mays (maize)Positive and negative results
97 papers in the same direction as this paper · 22 in the opposite direction
- positive
- positive
- positive
116 papers more in this group
See all 120 papers →tillage · nutrient: content · Zea mays (maize)Positive and negative results
92 papers in the same direction as this paper · 33 in the opposite direction · 1 reporting no difference from an alternative
- negative
- no effect
- negative
123 papers more in this group
See all 127 papers →nitrogen · nutrient: efficiency · Zea mays (maize)Positive and negative results
141 papers in the same direction as this paper · 42 in the opposite direction · 10 reporting no difference from an alternative
- negative
- negative
- no effect
190 papers more in this group
See all 194 papers →organic · yield · Zea mays (maize)Positive and negative results
329 papers in the same direction as this paper · 32 in the opposite direction · 11 reporting no difference from an alternative
- positive
- positive
- positive
369 papers more in this group
See all 373 papers →tillage · yield · Zea mays (maize)Positive and negative results
811 papers in the same direction as this paper · 230 in the opposite direction · 57 reporting no difference from an alternative
- positive
- no effect
- negative
1,095 papers more in this group
See all 1,099 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.