摘要
[目的]探讨不同植被类型土壤呼吸特征及其温度敏感性,为陆地生态系统碳循环研究提供理论支持。[方法]以太行山南麓裸地、草地、灌丛、林地为研究对象,采用长期定位观测和室内化验分析相结合的方法,研究不同季节土壤水热因素、呼吸特征及其温度敏感性。[结果]不同植被类型的土壤温度变化较大,均表现为1月初最低,8月下旬最高,8月以后土壤温度呈逐渐降低模式,相同月份土壤温度大致表现为:裸地>草地>灌丛>林地,局部有所波动。不同植被类型的土壤呼吸速率具有明显差异,季节变化特征一致;其中,土壤呼吸、异养呼吸和自养呼吸速率季节变化特征一致(倒V形变化规律),大致表现为:夏季>秋季>春季>冬季。不同植被类型的土壤呼吸湿度敏感性大致表现为:裸地<草地<灌丛<林地。由此说明植被类型是影响土壤呼吸温度敏感性的重要因素,并且夏季和秋季土壤呼吸Q 10显著高于春季和冬季。相关性分析表明土壤pH值与温度敏感性(Q 10)呈显著负相关(p<0.05),与有机碳含量呈显著正相关(p<0.05)。不同植被类型土壤异养呼吸夏季的贡献率最高,春季的贡献率最低,贡献率依次表现为:夏季>秋季>冬季>春季,自养呼吸贡献率随季节的变化呈逐渐增加趋势。[结论]异养呼吸对土壤总呼吸的贡献率大于自养呼吸,微生物参与下的异养呼吸成为土壤呼吸中最主要的组成部分。
[Objective]Soil respiration and its temperature sensitivity of different vegetation types were studied,in order to provide theoretical support for the assessment of terrestrial ecosystem carbon cycle.[Methods]Soil hydrothermal factors,respiration characteristics and temperature sensitivity in different seasons were studied in bare land,grassland,shrub and woodland at the southern foothill of Taihang Mountains by long-term location observation and laboratory analysis.[Results]Soil temperature of different vegetation types varied greatly with seasons,with the lowest value in the early January and the highest value in the late August.After August,soil temperature gradually decreased with time.The soil temperature in the same month was generally showed an oreder of bare land>grassland>shrubland>forestland,with the local fluctuations.Soil respiration rate of different vegetation types was significantly different and the seasonal variation characteristics were consistent.Among them,soil respiration,heterotrophic respiration and autotrophic respiration had the same seasonal variation characteristics(inverted V-shaped variation),which roughly showed as follows:summer>autumn>spring>winter.Soil respiration humidity sensitivity of different vegetation types was as follows:bare land<grassland<shrubland<forestland,indicating that vegetation types were the important driving factor for soil respiration temperature sensitivity.Q10 in summer and autumn was significantly higher than that in spring and winter.Correlation analysis showed that Q10 was significantly negatively correlated with pH value(p<0.05),and negatively correlated with the bulk density;Soil organic carbon was positively correlation with Q10(p<0.05).Moreover,the contribution rate of soil heterotrophic respiration was the highest in summer and the lowest in spring.The contribution rate of soil heterotrophic respiration was as follows:in summer>in autumn>in winter>in spring,and the contribution rate of autotrophic respiration gradually increased with season.[Conclusion]Heterotrophic respiration contributed more to soil respiration than autotrophic respiration,and soil heterotrophic respiration with microbial participation is the most important component of soil respiration.
作者
陈玮
Chen Wei(College of Resources and Environment, Shanxi Agricultural University, Taigu, Shanxi 030801, China)
出处
《水土保持通报》
CSCD
北大核心
2021年第2期92-98,共7页
Bulletin of Soil and Water Conservation
基金
山西农业大学科技创新基金项目“基于RS的太原矿山环境动态监测与评价研究”(2017007)。
关键词
土壤呼吸
季节动态
温度敏感性
太行山南麓
soil respiration
seasonal dynamics
temperature sensitivity
southern foothill of Taihang Mountains
