论文部分内容阅读
2011年5月—2012年4月,利用Li-6400系统测定秦岭小陇山锐齿栎林皆伐迹地的土壤呼吸速率,研究锐齿栎林皆伐迹地土壤呼吸速率日动态、月动态和土壤温湿度以及土壤理化性质对土壤呼吸的影响.结果表明:皆伐迹地和锐齿栎对照林地的土壤呼吸日动态和月动态均表现为单峰曲线,与土壤温度变化趋势相似;皆伐迹地和对照林地土壤呼吸速率的月均最大值均出现在7月,分别为4.63和4.01μmol·m-2·s-1,月均最小值均出现在2月,分别为0.10和0.30μmol·m-2·s-1;皆伐后4~6个月,皆伐迹地土壤呼吸速率月均值大于对照林地,此后则小于对照林地;土壤温度、湿度及二者交互作用的多元回归模型能够解释皆伐迹地土壤呼吸速率变化的89.6%~90.8%,解释对照林地的94.7%~95.5%;利用指数方程计算两样地土壤呼吸的Q10值,皆伐迹地和对照林地土壤呼吸的Q10值分别为3.47~4.22和3.54~3.96;皆伐迹地和对照林地年土壤碳释放量分别为344.8和512.9 g·m-2,冬季土壤碳释放量分别为24.2和40.9 g·m-2,占全年的7.0%和8.0%.
From May 2011 to April 2012, the soil respiration rate of Clear cut sharptooth oak stands in the Mt.Xiaoluoling was measured by Li-6400 system. The daily and seasonal dynamics of soil respiration rate and monthly dynamics Temperature and humidity as well as soil physical and chemical properties on soil respiration.The results showed that both the daily respiration and the monthly dynamic of soil respiration in both the clear cut and the Quercus acutissima forest showed a unimodal curve similar to that of the soil temperature, The maximum values of monthly average soil respiration rate in control forestland occurred in July, which were 4.63 and 4.01μmol · m-2 · s-1, respectively. The minimum monthly mean values of soil respiration rate in February were 0.10 and 0.30μmol · m- 2 · s-1. After 4 to 6 months of clear-cutting, the average monthly soil respiration rate in clear-cut sites was larger than that in the control forestland and thereafter smaller than the control forestland. Multiple regression models of soil temperature and humidity and the interaction between them could explain clear-cut The soil respiration rate of trace sites varied from 89.6% to 90.8%, accounting for 94.7% ~ 95.5% of the control forest land. Q10 values of soil respiration were calculated using exponential equation. The Q10 values of soil respiration in both clear-cut and control sites were 3.47 ~ 4.22 And 3.54 ~ 3.96; clear cut and control forest Release of soil carbon were 344.8 and 512.9 g · m-2, soil carbon emission winter were 24.2 and 40.9 g · m-2, accounting for 7.0% and 8.0% of the year.