Performance of Solid‐State Sensors for Continuous, Real‐Time Measurement of Soil CO₂ Concentrations

Abstract

Recent advances in sensor technology provide a robust capability for continuous measurement of soil gases. Th e performance of solid-state CO 2 sensors (Model GMM220 series, Vaisala, Inc., Helsinki, Finland) was evaluated in laboratory, greenhouse, and irrigated winter wheat (Triticum aestivum L.). In ambient CO 2 concentration, the GMM222 sensor averaged 427 ± 8.3 μL L −1 . Under variable CO 2 concentrations, the sensor was slightly lower than concentrations measured with an infrared gas analyzer (IRGA). In greenhouse pots planted with triticale (Triticale hexaploide Lart.) and an agricultural fi eld of irrigated winter wheat, soil CO 2 concentration exceeded the 10,000 μL L −1 limit of the GMM222. Alternatively, the GMM221 sensor, designed to measure between 0 and 20,000 μL L −1 , showed soil CO 2 concentrations were between 14,000 and 16,000 μL L −1 . Th e GMM222 accurately measures real-time soil CO 2 concentrations under fi eld conditions that were within the sensor detection limit. However, periods of high biological soil activity require the GMM221 sensor with a higher detection limit.

Vertical partitioning and controlling factors of gradient-based soil carbon dioxide fluxes in two contrasted soil profiles along a loamy hillslope

“…1). This tubing method is an adaptation of the technique presented by Young et al (2009). We inserted these tubes vertically into the soil, after creating boreholes with a diameter that equals the diam- eter of the PVC tubes.…”

Quantitative estimation and vertical partitioning of the soil carbon dioxide fluxes at the hillslope scale on a loess soil

“…The CO 2 sensor in the probe is based on the CARBOCAP lene) membranes and encapsulated in a tube to avoid soil particles entering the sensor and to limit water infiltration. This tubing method is an adaptation of the technique presented by Young et al (2009). These tubes were inserted vertically into the soil, after augering holes with a diameter that equals the diameter of the PVC tubes.…”

“…Davidson et al, 2002) or such 20 as the non-dispersive infra-red (NDIR) probes (e.g. Young et al, 2009) can be used. However the support scale and spatial resolution of these devices are often too small to make robust large scale assessment of C exchanges across the soil atmosphere interface.…”

Progress in the theory, hypothesis and application of the methods measuring soil CO₂ flux gradient

“…www.plant-ecology.com 中的根系分布、水分含量等因素(Wolf et al, 2011; 2 浓度的测定(Vargas et al, 2010)。这类探头可以安装于重新填埋的土壤洞穴内(Daly et al, 2009;Maier et al, 2010), 或放置于垂直地表的采样 管(Young et al, 2009;Sullivan et al, 2010)。包裹探 头的防水透气盖子能够让土壤气体与探头测量箱里 的气体达到平衡。这种进步使得土壤CO 2 浓度的连 续测量成为可能(Baldocchi et al, 2006;Vargas et al, 2011), 但连续测量时, 探头可能会加热土壤, 需要 注意探头测量间隔时间(Hirano et al, 2003; Jassal et 导致比箱式通量法得到更高或更低的土壤呼吸量 (Tang et al, 2003;Pingintha et al, 2010;Sullivan et al, 2010;Wolf et al, 2011), 需要将D s 模型的参数进行 本地化处理(Pavelka et al, 2018)。最近用箱式通量法 观 测 结 果 来 反 算 土 壤 有 效 扩 散 系 数 (Sánchez-Cañete et al, 2017;Yang et al, 2018), 土壤通量梯度 法与箱式通量法均取得较好的效果。通常基于测量 参数进行D s 模拟, 并利用模拟后的D s 作为土壤梯度 法的计算参数进行通量计算, 此时, 土壤梯度法与箱式通量法的测量结果较一致(de Jong et al, 1979; Liang et al, 2004 Liang et al, , 2010 Jassal et al, 2005; Kusa et al,天 呼 吸 δ 13 C 平 均 值 为 -24.8‰, 夜 间 的 平 均 值 为 -26.9‰, 体现了自养呼吸和异养呼吸的时间变异特 征(van Asperen et al, 2017)。通过对德国森林样地 0-100 cm 土 壤 的 研 究 , 发 现 欧 洲 水 青 冈 (Fagus sylvatica)林地随土壤深度增加, 土壤CO 2 δ 13 C逐渐 增加, 变异区间范围为-22‰--21‰, 而欧洲赤松 (Pinus sylvestris)林地表是-19.2‰, 在10-20 cm随 着 深 度 从 -22‰ 增 加 到 -19‰ (Jochheim et al,…”