不同粒级土壤团聚体呼吸特征及其对碳排放的贡献_王菁

植物科学学报2014，32（6）：586 593Plant Science Journal

DOI ：10.11913/PSJ.2095－0837.2014.60586

不同粒级土壤团聚体呼吸特征及其对碳排放的贡献

王菁

1，3

，陈防1，刘毅1，

2*

（1．中国科学院武汉植物园，中国科学院水生植物与流域生态重点实验室，武汉430074；2．中国科学院水利部水土保持研究所，黄土高原土壤侵蚀与旱地农业国家重点实验室，陕西杨凌712100；3．中国科学院大学，北京100049）

摘要：通过土盆培养试验研究了不同粒级黄棕壤团聚体呼吸特征及其对碳排放的贡献，结果表明：各粒级土壤

团聚体及原状土在培养初期土壤呼吸速率较高，之后逐渐降低。在整个培养期间原状土保持了最大的土壤呼吸速率；土壤团聚体类型对土壤呼吸速率影响较大，3种粒级团聚体土壤呼吸速率大小表现为（＞5mm ）＞（＜1mm ）≈（1 5mm ），其中以＞5mm 团聚体对土壤碳排放的贡献最大。相关性分析表明，指数模型能较好地描述不同粒级团聚体的土壤呼吸对温度变化的响应；Q 10值介于2.53 5.11之间且与土壤有机碳、全氮含量的变化规律基本一致，表现为＞1mm 团聚体有机碳、全氮含量和Q 10值较大，＞5mm 、1 5mm 团聚体有机碳、全氮含量和Q 10值相对较低，说明土壤团聚体粒级越小，其呼吸速率对温度越敏感。土壤有机碳、氮含量与土壤结构是影响土壤呼吸温度敏感性的重要因素。关键词：土壤团聚体；土壤呼吸；碳排放；温度敏感性中图分类号：S154.1

文献标识码：A

文章编号：2095-

0837（2014）06-0586-08收稿日期：2014-04-23，退修日期：2014-05-05。

基金项目：国家自然科学基金（31370529，

31100386）；黄土高原土壤侵蚀与旱地农业国家重点实验室开放基金（K318009902-1415）。作者简介：王菁（1989－），女，硕士研究生，主要从事农业生态学方面的研究（E-mail ：642380047@ ）。*通讯作者（

Author for correspondence.E-mail ：lyle3521@ ）。

Ｒespiration C haracteristics of Different S ized S oil A ggregates

and T heir C ontribution to C arbon E missions

WANG Jing 1，3，CHEN Fang 1，LIU Yi 1，

2*

（1．Key Laboratory of Aquatic Botany and Watershed Ecology ，Wuhan Botanical Garden ，Chinese Academy of Sciences ，

Wuhan 430074，China ；2．State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau ，

Institute of Water and Soil Conservation ，Chinese Academy of Sciences and Ministry of Water Ｒesources ，Yangling ，

Shaanxi 712100，China ；3．University of Chinese Academy of Sciences ，Beijing 100049，China ）

A bs tract ：The respiration characteristics of different sized yellow brown soil aggregates and their contribution to carbon emissions were assessed by soil pot experiment．Ｒesults showed that the respiration rates of aggregates and homogenized soil were highest at the beginning of the incubation ，and then showed a descending tendency during the period of incubation．During the incubation time ，the homogenized soil had the highest respiration rate．The respiration rates varied with aggregate size ：（＞5mm ）＞（＜1mm ）≈（1 5mm ）．This indicated that the largest macroaggregates （＞5mm ）had the highest contribution to carbon emissions．Correlation analysis showed that the respiration rates of different sized soil aggregates were significantly and exponentially correlated with soil temperature．The Q 10values ranged from 2.53to 5.11and had the same variation tendency in different aggregates with soil organic carbon （SOC ）and total nitrogen （TN ）．The ＜1mm aggregates had the highest Q 10value and SOC and TN contents ，while ＞5mm and 1 5mm aggregates had lower Q 10values and SOC and TN contents．Our results suggested that both the contents of SOC and TN and the soil structure affected temperature sensitivity of soil respiration．