黑河中游湿地胡杨蒸腾速率与叶性状的关联性分析

干旱区湿地植物叶片蒸腾作用与叶性状的关联性研究,对揭示植物叶片叶脉网络性状、叶片形态构建模式与植物体内水分平衡间的内在联系至关重要.以黑河中游湿地胡杨(Populus euphratica)为研究对象,按胡杨林距离水域的远近分别设置:I(离水域30～110 m,土壤含水量(SMC)58.23％)、II(离水域160～2...

Studies of correlation between the transpiration rate and leaf traits of Populus euphratica in the middle reaches of the Heihe River wetland

Study of the correlation between transpiration and vein characters in wetland plants in arid regions is of great importance in understanding the internal relationship between vein network characters,leaf morphology,and water balance in plants.Our aim was to examine the correlation between the transpiration rate and the leaf traits of Populus euphratica at different levels of soil moisture content(SMC).Our study area was in the middle reaches of the Heihe River wetland,Gansu Province,China(98°25′56.98″E,39°54′10.55″).We divided the sample area into three levels based on the distance from water:Plot Ⅰ(30-110 m from water,SMC 58.23%),plot Ⅱ(160-240 m away from water,SMC 40.53%),and plot Ⅲ(290-370 m from water,SMC 28.36%).The findings revealed that as the SMC decreased,the crown density,diameter at breast height,plant height,vein diameter,leaf area,and specific leaf area of P.euphratica decreased gradually,whereas the opposite was the case for leaf thickness,vein density,PAR,Pn,Tr,Gs,and Ci.There was a highly significant positive correlation between Tr and vein density at three plots(P<0.01),and the opposite correlation was seen between leaf area and specific leaf area.There was a highly significant negative correlation between Tr and vein diameter in plots Ⅰ and Ⅲ(P<0.01),whereas there was a significantly negative correlation between Tr and vein diameter in plot Ⅱ(P<0.05).To adapt to the gradient change of soil water,P.euphratica populations regulated the water consumption due to leaf transpiration by optimizing the resource input of leaf vein characters to realize effective utilization of soil water and reasonable distribution of photosynthetic carbon assimilation products;this reflected the ecological adaptation mechanism of inland river wetland plants in arid areas to special habitats.