A multichannel automated chamber system for continuous measurement of forest soil CO2 efflux
A multichannel automated chamber system for continuous measurement of forest soil CO2 efflux
复制标题
DOI：
10.1093/treephys/23.12.825
复制
发表时间：
2003-08-01
期刊：
影响因子：
4
通讯作者：
Fujinuma, Y
中科院分区：
文献类型：
--
作者：
Liang, NS;Inoue, G;Fujinuma, Y
我们开发了一种快速响应的多室系统，用于测量土壤表面CO2排放（F.）。腔室（90 x 90 x 50 cm，L x W x H）具有自动打开和关闭的盖子，并与配备有16通道气体采样器的单个CO2分析仪并联连接。在测量之间，将箱盖升高以允许降水和落叶到达封闭的土壤表面。当腔室关闭时，用缓冲良好的环境空气（125 1 min（-1））通风，环境空气通过腔室一侧侧壁上的入口进入，并通过相对侧壁上的大通风口排出。腔室内部和外部之间的压力差小于0.22 Pa。两个额外的混合风扇在土壤表面以上20 cm处保持0.3 +/- 0.1 in s（-1）的空气速度。从每个腔室的入口和出口连续抽出空气，并依次进料至红外CO2分析仪。利用该系统，对40年生温带赤松（Pinus densiflora Sieb. & Zucc. 2001年2月8日至5月30日的森林。平均F，从2月初的0.9 mumol m（-2）s（-1）稳步增加到5月底的4.6 mumol m（-2）s（-1）。F-c与土壤表层温度呈显著正相关（r = 0.896; P < 0.0001），Q（10）值为2.8。F-c的空间变异在非生长季大于生长季。测量没有被雨或雪中断。
We developed a fast-response multi-chamber system for measuring soil-surface CO2 efflux (F.). The chambers (90 x 90 x 50 cm, L x W x H) had lids that opened and closed automatically, and were connected in parallel to a single CO2 analyzer equipped with a 16-channel gas sampler. Between measurements the chamber lids were raised to allow precipitation and leaf litter to reach the enclosed soil surface. When a chamber was closed, it was ventilated with well-buffered ambient air (125 1 min(-1)) that entered by an inlet on one chamber sidewall and exited through a large vent on the opposite sidewall. The pressure difference between the inside and outside of the chamber was less than 0.22 Pa. Two additional mixing fans maintained an air speed of 0.3 +/- 0.1 in s(-1) at 20 cm above the soil surface. Air was withdrawn continuously from the inlets and outlets of each chamber, and fed sequentially to an infrared CO2 analyzer. With this system, we measured F-c in a 40-year-old temperate Pinus densiflora Sieb. & Zucc. forest from February 8 to May 30, 2001. Mean F, increased steadily from 0.9 mumol m(-2) s(-1) at the beginning of February to 4.6 mumol m(-2) s(-1) by the end of May. There was a statistically significant correlation between F-c and surface soil temperature (r = 0.896; P < 0.0001), and the Q(10) value was 2.8. Spatial variation of F-c was higher in the non-growing season than in the growing season. Measurements were not interrupted by either rain or snow.