文献类型：期刊文献

中文题名：模拟氮沉降对长江中下游滩地杨树林土壤呼吸各组分的影响

英文题名：Effects of simulated nitrogen deposition on the each component of soil respiration in the Populus L. plantations in a riparian zone of the mid-lower Yangtze River

作者：吴迪[1,2] 张蕊[3] 高升华[4] 付晓[3] 邓红兵[3] 邵国凡[1] 张旭东[4]

第一作者：吴迪

机构：[1]中国科学院城市环境研究所;[2]中国科学院大学;[3]中国科学院生态环境研究中心,城市与区域生态国家重点实验室;[4]中国林业科学研究院林业研究所

年份：2015

卷号：35

期号：3

起止页码：717-724

中文期刊名：生态学报

外文期刊名：Acta Ecologica Sinica

收录：CSTPCD;;Scopus;北大核心:【北大核心2014】；CSCD:【CSCD2015_2016】；

基金：国家“十二五”农村领域科技计划子课题(2011BAD38B0405)

语种：中文

中文关键词：土壤呼吸;氮沉降;杨树;滩地;长江中下游

外文关键词：soil respiration; nitrogen deposition; Populus plantation; riparian zone; the mid-lower Yangtze River

分类号：S792.11

摘要：土壤呼吸是土壤碳库向大气输出碳的主要途径,也是大气CO2重要的源。活性氮的生成和沉降速率的增加影响了生态系统的碳循环,研究氮沉降量增加对土壤呼吸各组分的影响,对于了解土壤呼吸在气候变化中的作用有重要意义。以长江中下游滩地杨树人工林为对象,通过定位模拟氮沉降实验,研究了滩地杨树人工林生态系统土壤呼吸的变化特征和土壤呼吸各组分对几种氮沉降量浓度的响应。结果表明:土壤呼吸及其各组分均有明显的季节变化特征,由于试验地发生淹水现象而呈现双峰曲线特征;模拟氮沉降显著抑制了杨树人工林土壤呼吸作用。对照组、低氮水平处理组、中氮水平处理组和高氮水平处理组的土壤总呼吸速率的年均值分别为3.21、2.82、2.82、2.72μmol m-2s-1,相当于每年排放出的CO2的量分别为42.06、37.06、36.20、35.69 t/hm2;各组土壤微生物呼吸的年均值分别为2.12、2.05、1.96、1.99μmol m-2s-1,模拟氮沉降抑制了土壤微生物呼吸作用,但其影响不显著;各组根呼吸的年平均值分别为1.09、0.77、0.86、0.75μmol m-2s-1,模拟氮沉降对根系呼吸有显著的抑制作用。
Continuous increasing production and deposition of nitrogen will have a significant impact on carbon cycling of ecosystems. Soil respiration is the important component of carbon cycling in terrestrial ecosystems, the only way to release carbon into atmosphere from soil carbon, and an important source of atmospheric CO2. Study on the response of soil respiration to nitrogen deposition is significant for understanding the role of soil respiration in the mitigation of climate change. By using the experimental method of positioning the simulated nitrogen deposition, this research was focused mainly on the variations in soil respiration, and the short-term response of each component of soil respiration to different levels of nitrogen deposition, and revealed the relationship between carbon and nitrogen cycling of Populus L. plantations in a riparian zone of Yangtze River. We found that： （1） Soil respiration and its components had significant seasonal variations, presenting bimodal curves because of seasonal flooding. Soil respiration rate showed a downward trend because of rising of groundwater level in June and July, reached the maximum in August and the minimum in December and January. （2） The average of annual total soil respiration of control, low-nitrogen, medium-nitrogen and high-nitrogen treatments in the poplar plantations were 3.21, 2.82, 2.82 μmol m-2 s-1 and 2.72 μmol m-2 s-1 of CO2, respectively, equivalent to 42.06, 37.06, 36.21 t/hm2 and 35.69 t/hm2 of = CO2 released annually. The annual amounts of CO2 released from low-nitrogen, medium-nitrogen and high-nitrogen treatments were reduced by 12.35%, 14.45% and 15.73%, respectively. Nitrogen deposition significantly restrained the function of total soil respiration. （3） The average of annual soil microbial respirations of control, low-nitrogen, medium-nitrogen and high-nitrogen treatments in the poplar plantations were 2.12, 2.05, 1.96 μmol m-2 s-1 and 1.99 μmol m-2 s-1, respectively, equivalent to 27.85, 26.98, 25.24 t/hm2 and 25.95 t/hm2 of CO2 released per annual. The annual amount of CO2 released from low-nitrogen, medium-nitrogen and high-nitrogen treatments were reduced by 3.23%, 9.70% and 7.07%, respectively. The magnitude of the decreases was significantly lower than that for the total soil respiration. Nitrogen deposition restrained the function of soil microbial respiration, and this action is not significant. （4） The average of annual root respirations of control, low-nitrogen, medium-nitrogen and high-nitrogen treatments in the poplar plantations were 1.09, 0.77, 0.86 μmol m-2 s-1 and 0.75 μmol m-2 s-1, respectively, equivalent to 14.22, 10.08, 10.96 t/hm2 and 9.97 t hm-2 of CO2 released annually. The annual amount of CO2 released from low-nitrogen, medium-nitrogen and high-nitrogen treatments were reduced by 30.31%, 23.81% and 31.07%, respectively. Such levels of decreases were significantly higher than those for the total soil respiration and the soil microbial respiration. Nitrogen deposition significantly restrained the root respiration.