甘肃华亭侏罗系Phoenicopsis(Phoenicopsis) angustifolia Heer的表皮构造与碳同位素特征

Cuticular composition and carbon isotope characteristics of Jurassic Phoenicopsis(Phoenicopsis) angustifolia Heer from Huating in Gansu province,China

描述了甘肃华亭中侏罗世植物化石狭叶拟刺葵Phoenicopsis(Phoenicopsis)angustifolia Heer的角质层微细构造。利用化石的现存最近对应种Ginkgo biloba L。与化石Ph.(Ph.)angustifolia Heer的气孔比率,恢复的华亭中侏罗世的大气CO_2体积分数为1.274×10^(-3),这一结果与邻区兰州窑街银杏属化石植物恢复的中侏罗世CO_2体积分数相一致,表明拟刺葵属植物是恢复大气CO_2体积分数的良好材料。此外,利用Ph.(Ph.)angustifolia角质层碳同位素值估算了其水分利用率为223.0 mmol/mol,明显高于现代银杏的数值,表明当时气候比较湿润。

Fossil Phoenicopsis（Phoenicopsis） angustifolia Heer was collected from the middle jurassic of Huating Coal Mine, Gansu province. The cuticle was observed under a light microscope and a scanning electron microscope. Based on the stomatal ratio of the nearest living equivalent species Ginkgo biloba L. to the present fossil, the CO2 concentration in the middle jurassic at Huating was estimated at about 1.274×10^-3. The estimated value of CO2 concentration in the middle jurassic coincided with the results from the adjacent Yaojie area, which shows that the fossil plant of Phoenicopsis is suitable for paleoclimatic reconstruction. In addition, the water use efficiency of Ph.（Ph.） angustifolia is 223.0 mmol/mol, exceedingly higher than that of modern G. biloba, indicating a humid paleoclimate in the middle jurassic at Huating.