Abstract
Atmospheric nitrogen input has been a severe challenge worldwide. The influences of N deposition on carbon cycling, loss, and storage have been recognized as a critical issue. This study aimed to assess the immediate responses of soil respiration to different N deposition treatments in radiata pine (Pinus radiata D. Don) and chestnut-leaved oak (Quercus castaneifolia C. A. Mey) plantations within 12 months. N treatments were performed monthly at levels of 0, 50, 100, and 150 kg N ha−1 year−1 from October 2017 to September 2018. Litterfall was collected and analyzed seasonally for its mass and C content. Within the 0–10 cm depth of mineral soil in both plantations, parameters such as total nitrogen, pH, microbial biomass carbon (MBC), organic carbon (OC), and fine root biomass were measured seasonally. Soil respiration (Rs) was determined through monthly measurements of CO2 concentration in the field using a portable, closed chamber technique. The control plots exhibited the highest Rs during spring (2.96, 2.85 μmol CO2 m−2 s−1) and summer (2.92, 3.1 μmol CO2 m−2 s−1) seasons in oak and pine plantations, respectively. However, the introduction of nitrogen significantly diminished Rs in both plantations. Moreover, N treatments caused a notable reduction of soil MBC and fine root biomass. Soil microbial entropy and the C/N ratio were also significantly decreased by nitrogen treatments in both plantations, with the most prominent effects observed in summer. The observed decline in Rs in N-treated plots can be attributed to the decrease in MBC and fine root biomass, potentially with distinct contributions of these components in the pine and oak plantations. Our findings suggested that N-induced alteration in soil carbon dynamics was more pronounced in the oak plantation, which resulted in more SOC accumulation with increasing N inputs, while the pine plantation showed no significant changes in SOC.
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
Oak control plots had the highest spring soil respiration, 2.96 μmol CO2 m−2 s−1.
QuercusOrganisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The control plots exhibited the highest Rs during spring (2.96, 2.85 μmol CO2 m−2 s−1) and summer (2.92, 3.1 μmol CO2 m−2 s−1) seasons in oak and pine plantations, respectively.”
Claim · model-written summary
Pine control plots had the highest spring soil respiration, 2.85 μmol CO2 m−2 s−1.
PinusOrganisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The control plots exhibited the highest Rs during spring (2.96, 2.85 μmol CO2 m−2 s−1) and summer (2.92, 3.1 μmol CO2 m−2 s−1) seasons in oak and pine plantations, respectively.”
Claim · model-written summary
Oak control plots had the highest summer soil respiration, 2.92 μmol CO2 m−2 s−1.
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The control plots exhibited the highest Rs during spring (2.96, 2.85 μmol CO2 m−2 s−1) and summer (2.92, 3.1 μmol CO2 m−2 s−1) seasons in oak and pine plantations, respectively.”
Claim · model-written summary
Pine control plots had the highest summer soil respiration, 3.1 μmol CO2 m−2 s−1.
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The control plots exhibited the highest Rs during spring (2.96, 2.85 μmol CO2 m−2 s−1) and summer (2.92, 3.1 μmol CO2 m−2 s−1) seasons in oak and pine plantations, respectively.”
Claim · model-written summary
Nitrogen significantly reduced soil respiration in oak plantations.
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The control plots exhibited the highest Rs during spring (2.96, 2.85 μmol CO2 m−2 s−1) and summer (2.92, 3.1 μmol CO2 m−2 s−1) seasons in oak and pine plantations, respectively. However, the introduction of nitrogen significantly diminished Rs in both plantations.”
t0“Pine and Oak Monocultures”
Claim · model-written summary
Nitrogen significantly reduced soil respiration in pine plantations.
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The control plots exhibited the highest Rs during spring (2.96, 2.85 μmol CO2 m−2 s−1) and summer (2.92, 3.1 μmol CO2 m−2 s−1) seasons in oak and pine plantations, respectively. However, the introduction of nitrogen significantly diminished Rs in both plantations.”
t0“Pine and Oak Monocultures”
Claim · model-written summary
Nitrogen reduced soil microbial biomass carbon in both plantations.
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“N treatments caused a notable reduction of soil MBC and fine root biomass.”
t0“Pine and Oak Monocultures”
Claim · model-written summary
Nitrogen reduced fine root biomass in both plantations.
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“N treatments caused a notable reduction of soil MBC and fine root biomass.”
t0“Pine and Oak Monocultures”
Claim · model-written summary
Nitrogen significantly decreased soil microbial entropy in both plantations.
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Soil microbial entropy and the C/N ratio were also significantly decreased by nitrogen treatments in both plantations, with the most prominent effects observed in summer.”
t0“Pine and Oak Monocultures”
Claim · model-written summary
Nitrogen significantly decreased the C/N ratio in both plantations.
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Soil microbial entropy and the C/N ratio were also significantly decreased by nitrogen treatments in both plantations, with the most prominent effects observed in summer.”
t0“Pine and Oak Monocultures”
Claim · model-written summary
Reduced microbial biomass carbon and fine root biomass may explain lower respiration.
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The observed decline in Rs in N-treated plots can be attributed to the decrease in MBC and fine root biomass, potentially with distinct contributions of these components in the pine and oak plantations.”
Claim · model-written summary
Nitrogen effects on soil carbon dynamics were more pronounced in oak than pine.
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“N-induced alteration in soil carbon dynamics was more pronounced in the oak plantation”
Claim · model-written summary
Soil organic carbon accumulation increased with nitrogen inputs in oak.
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“more SOC accumulation with increasing N inputs”
t0“Pine and Oak Monocultures”
Claim · model-written summary
Pine soil organic carbon did not change significantly with nitrogen.
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“more SOC accumulation with increasing N inputs, while the pine plantation showed no significant changes in SOC.”
The same questions in other papers
nitrogen · growth · PinusPositive and negative results
1 paper in the same direction as this paper · 3 in the opposite direction
- positive
- positive
- positive
1 paper more in this group
See all 5 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.