Roderick Michael L, Berry Sandra L
Ecosystem Dynamics Group and C. R. C. for Greenhouse Accounting, Research School of Biological Sciences, Institute of Advanced Studies, The Australian National University, Canberra ACT 0200, Australia.
New Phytol. 2001 Mar;149(3):473-485. doi: 10.1046/j.1469-8137.2001.00054.x.
• An hydraulic model of a tree stem is presented to help understand how the carbon storage in ecosystems varies with changing environmental conditions. • The model is based on the assumption that a tree stem is a collection of parallel pipes and was used to (qualitatively) predict how the mass concentration of dry matter ([D]) would vary with water temperature (via changes in viscosity), nitrogen supply and atmospheric CO . • There was qualitative agreement between model predictions and observed gross trends. The model predicted that the flow rate would be relatively insensitive to variations in [D] in angiosperm stems; this was consistent with observations. It is concluded that other factors need to be considered to explain variations in [D] in angiosperm wood. The flow rate of water through gynmosperm stems was predicted to be very sensitive to variations in [D] and the model explained why [D]; decreases with decreases in water temperature, decreases with increases in nitrogen supply and increases with elevated CO . • The model captured some of the important underlying relations linking water transport with wood density and environment and qualitative testing of the model is recommended.
• 提出了一种树干的水力模型，以帮助理解生态系统中的碳储存如何随环境条件的变化而变化。• 该模型基于这样的假设：树干是一组平行管道，并被用于（定性地）预测干物质的质量浓度（[D]）如何随水温（通过粘度变化）、氮供应和大气CO₂而变化。• 模型预测与观察到的总体趋势之间存在定性一致性。该模型预测，流速对被子植物茎中[D]的变化相对不敏感；这与观察结果一致。得出的结论是，需要考虑其他因素来解释被子植物木材中[D]的变化。预测通过裸子植物茎的水流速对[D]的变化非常敏感，并且该模型解释了为什么[D]会随着水温降低而降低，随着氮供应增加而降低，随着CO₂升高而增加。• 该模型捕捉到了一些将水分运输与木材密度和环境联系起来的重要潜在关系，建议对该模型进行定性测试。
