摘要
研究模拟氮沉降增加对土壤呼吸温度敏感性的影响可以降低全球变化条件下土壤碳收支评估的不确定性。本研究用meta分析方法探讨了模拟氮沉降增加对中国陆地生态系统土壤呼吸温度敏感性(Q_(10))的影响。结果发现:模拟氮沉降增加整体上对Q_(10)影响不显著(0.49%),但显著降低了高原气候带生态系统Q_(10)(16.32%),显著增加了沼泽Q_(10)(38.19%)。效应大小与试验模拟的氮沉降量有一定关系,模拟氮沉降量小于50 kg·hm^(-2)·a^(-1)时Q_(10)增加2.59%,模拟氮沉降量为50～150和大于150 kg·hm^(-2)·a^(-1)时Q_(10)分别降低4.33%和1.61%。使用只含硝态氮的氮肥显著增加了Q_(10)(34.33%),而施加尿素的生态系统Q_(10)则显著降低(8.11%)。模拟氮沉降的时间超过15个月显著降低Q_(10)(19.24%)。模拟氮沉降影响土壤呼吸温度敏感性可能是由于氮通过影响土壤养分而影响了根系和土壤微生物的新陈代谢,进而影响土壤呼吸,使土壤呼吸对温度的敏感性不同。
Understanding the effects of simulated N deposition on temperature sensitivity of soil respiration(Q10)can reduce the uncertainty in the assessment of soil carbon budget under global change scenarios.In this study,60 literatures on the effects of simulated N deposition on Q10 in China’s terrestrial ecosystems were investigated by meta analysis.The results showed that the effects of simulated N deposition on Q10 were not significant(0.49%).Nitrogen deposition had negative effects on Q10 in the plateau climate zone(16.32%)and positive effects on that in marsh(38.19%).The effect size was related to the dosage of simulated N deposition.When simulated N deposition dosage was less than 50 kg·hm-2·a-1,Q10 increased by 2.59%;when the dosage was 50-150 kg·hm-2·a-1 and greater than 150 kg·hm-2·a-1,Q10 decreased by 4.33%and1.61%,respectively.The deposited nitrate nitrogen significantly increased Q10(34.33%),while urea application significantly decreased Q10(8.11%).Moreover,simulated N deposition with a duration over 15 months significantly reduced Q10(19.24%).The alteration of Q10 by simulated N deposition may be due to the alteration of the metabolism of roots and soil microbes.
作者
徐丽
杨雁茹
张军辉
冯月
XU Li;YANG Yan-ru;ZHANG Jun-hui;FENG Yue(Shenyang Jianzhu University,Shenyang 110168,China;Shenyang Institute of Applied Ecology,Chinese Academy of Science,Shenyang 110016,China)
出处
《生态学杂志》
CAS
CSCD
北大核心
2019年第5期1560-1569,共10页
Chinese Journal of Ecology
基金
国家自然科学基金项目(41675150和41430639)资助
关键词
模拟氮沉降
土壤呼吸
温度敏感性
META分析
simulated N deposition
soil respiration
temperature sensitivity
meta analysis
