Jeffries D L, Link S O, Klopatek J M
Division of Science and Mathematics, University of the Ozarks, Clarksville, Arkansas 72830.
Pacific Northwest Laboratory, Richland, Washington 99352.
New Phytol. 1993 Oct;125(2):391-396. doi: 10.1111/j.1469-8137.1993.tb03891.x.
The carbon dioxide exchange of Microcoleus- and Scytonema-dominated cryptogamic crusts as related to dehydration was measured in the laboratory with a modified discrete sampling technique and infrared gas analysis. The dehydration curves predicted that carboxylation and dark respiration rates for both crust types would become zero at from 4 to 5% water content (W) (approximately 16-23% soil saturation), with the water contents at which the rates became zero significantly lower in the second treatment cycle than the first. The dehydration curves predicted that net photosynthesis rates would become zero at 6.7-11.2% W (27-44% soil saturation), with the water contents at which the rates became zero significantly higher in the second cycle of treatment than the first.
在实验室中，采用改良的离散采样技术和红外气体分析法，测量了以微鞘藻属和席藻属为主的隐花植物结皮的二氧化碳交换与脱水的关系。脱水曲线预测，两种结皮类型的羧化作用和暗呼吸速率在含水量（W）为4%至5%（约为土壤饱和度的16%-23%）时将变为零，且在第二个处理周期中速率变为零的含水量显著低于第一个周期。脱水曲线预测，净光合速率在含水量为6.7%-11.2%（土壤饱和度的27%-44%）时将变为零，且在第二个处理周期中速率变为零的含水量显著高于第一个周期。
