Schwarz P A, Fahey T J, Dawson T E
Department of Natural Resources, Fernow Hall, Cornell University, Ithaca, New York 14853, USA.
Tree Physiol. 1997 Mar;17(3):187-94. doi: 10.1093/treephys/17.3.187.
Net photosynthesis and stomatal conductance were measured in ten red spruce (Picea rubens Sarg.) saplings, growing near Ithaca, New York, throughout the early spring and late-fall growing periods. Gas exchange and daily minimum and maximum soil and air temperatures were also measured. Linear regression analysis showed that rates of net photosynthesis were positively correlated with both minimum daily soil and air temperatures but that minimum soil temperature was a better predictor of net photosynthesis. Moreover, net photosynthesis was more sensitive to changes in soil temperature than to changes in air temperature, and photosynthesis was approximately twice as sensitive to temperature changes during the fall than during the spring.
在纽约伊萨卡附近生长的10株红云杉（Picea rubens Sarg.）幼树的整个早春和秋末生长期间，测量了其净光合作用和气孔导度。还测量了气体交换以及每日土壤和空气的最低和最高温度。线性回归分析表明，净光合作用速率与每日土壤和空气最低温度均呈正相关，但土壤最低温度是净光合作用的更好预测指标。此外，净光合作用对土壤温度变化比对气温变化更敏感，并且秋季光合作用对温度变化的敏感性约为春季的两倍。
