Systems for soil microclimatic manipulation and high frequency monitoring of decomposition rates

迫切需要进行实地研究，以确定土壤碳储量对气候变化的实际而非理论的原位反应。 这一研究领域的主要挑战是解决和/或控制变量，以保持参数（如水分）恒定，以便准确评估导致土壤有机质损失或储存的驱动和限制因素。 土壤碳研究领域的另一个实地挑战是量化不同碳库之间的分解率，这一点至关重要，因为据认为，深层的、难消化的土壤有机质拥有大部分长期固碳能力。通过使用地下，高时间分辨率的监测方法，结合小气候操作技术借用污染物生物修复研究，它是可能的测试新的问题，在土壤碳稳定性，即许多物理参数的影响，而不是在自然环境中的土壤碳损失的温度。 迄今为止，还没有使用现场实验方法来明确测试这些物理因素的重要性，但已知它们在许多地区（特别是高纬度地区）起作用，以稳定土壤碳并保护其免受分解。 我建议建立四个一次性系统的自动化控制和高频监测土壤分解率的土壤物理因素，特别是水分，氧合和温度的操纵。 实际上，这些系统中的每一个都构成了“实地实验室”。 我请求四个系统在加拿大大西洋地区的主要森林生物群落中进行操纵实验--北方森林、亚北方森林、安第斯森林和圣劳伦斯大湖。

Field studies are sorely needed to establish the actual, rather than theoretical, in-situ response of soil carbon stocks to climate change.  The major challenge in this area of research is resolution and/or control of variables to hold parameters (e.g. moisture) constant for accurate assessments of driving and limiting factors that contribute to loss or storage of soil organic matter.  Another in-situ challenge in the area of soil carbon research lies in the quantification of decomposition rates among different carbon pools, which is critical since deeper, recalcitrant soil organic matter is thought to hold the majority of long-term sequestration capacity. By using a subsurface, high-temporal resolution monitoring methodology in conjunction with microclimatic manipulation techniques borrowed from contaminant bioremediation studies, it is possible to test new questions in soil carbon stability, namely the effect of the numerous physical parameters other than temperature on soil carbon loss in natural settings.  To date, an in-situ experimental approach has not been used to explicitely test the significance of these physical factors, but it is known that they act in many areas (especially high latitudes) to stabilize soil carbon and protect it from decomposition.  I propose to construct four one-off systems for automated control and high frequency monitoring of soil decomposition rates in response to manipulations of soil physical factors, in particular moisture, oxygenation, and temperature.  In effect, each of these systems constitutes a "field laboratory".  I am requesting four systems to perform manipulative experiments in each of Atlantic Canada's major forest biomes - Boreal, Sub-Boreal, Acadian Forest and Great-Lakes St. Lawrence.