Seasonal responses of soil respiration to elevated CO2and N additionin young subtropical forest ecosystems in southern China |
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| 出 版 社:Ecological Engineering |
| 发表时间:2013 |
| 台 站:
鼎湖山森林生态系统定位研究站
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| 作 者:邓琦,周国逸等 |
| 点 击 率:583663 |
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| 关 键 字(英文):Elevated CO2,Nitrogen deposition,Soil water feedback,Soil respiration,Soil carbon sequestration,Subtropical forest |
| 摘 要(英文):tAtmospheric carbon dioxide (CO2) concentration and nitrogen (N) deposition may interactively impactsoil respiration in terrestrial ecosystems. However, the effects of elevated CO2and N deposition on soilrespiration are not fully understood especially in subtropical forest ecosystems in southern China whereambient N deposition is high. In this study, we investigated the seasonal responses of soil respiration toelevated CO2and N addition in young subtropical forest ecosystems in southern China using open-topchambers. Two CO2treatment levels (i.e., ambient CO2and 700 mol mol−1) and two N levels (i.e., ambientand 100 kg N ha−1yr−1) were considered. Forty-eight 1–2 years old seedlings (eight seedlings per each of6 species) were planted in each chamber. In the wet season, soil respiration significantly enhanced underelevated CO2and N addition with no interactive effect. There was not significant relationship betweentreatment-enhanced soil respiration and soil moisture in the wet season, suggesting that increases in soilrespiration resulted in large part from treatment-induced increases in tree growth and C inputs. In the dryseason, soil respiration significantly enhanced under elevated CO2, but did not significantly change underN addition. The N-induced change in soil respiration negatively corrected with soil moisture in the dryseason, indicating that decrease in soil moisture under N addition, together with increase in tree growthinteractively resulted in negligible net change in soil respiration. Our results highlighted the seasonalimportance of environmental controls under elevated CO2and N deposition in the assessment of soil Csequestration potential in subtropical forest ecosystems in southern China. |
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邓琦-2013-Ecological Engineering-Seasonal responses of soil respiration to elevated CO2and N addition in young subtropical forest ecosystems in southern China.pdf |