4个树种木质部栓塞与N素营养关系的研究

以刺槐、白榆、元宝枫及女贞等4个树种的1年生枝条为对象,采用盆栽控水的方法,研究4个树种在2个水分水平,2种N肥处理下,木质部栓塞的程度与N素营养的关系.结果表明,干旱胁迫下,N肥可以减小苗木木质部栓塞的发生.正常生长时,N肥能够加剧栓塞的程度.因树种自身耐旱方式不同,其栓塞发生对N素营养的敏感性也各异.木质部栓塞发生,不仅受N素营养的影响,同时是水势、大气温度、相对湿度等多个生理生态因子共同影响的结果.

Relationships Between Xylem Embolism and Nitrogen Fertilization in Four Woody Plants

Relationships between degree of xylem embolism and nitrogen fertilization in four woody plants under two soil water horizons and two nitrogen treatments were studied by controlling soil moisture of potted plant. The results showed that, under drought stress nitrogen could decrease the degree of xylem embolism, but contrary was observed under enough water supplies. Because of different drought-resistant strategy, the sensitivity of the trees to nitrogen was different. However, the degree of xylem embolism was influenced not only by nitrogen fertilization, but also by common effects of several ecophysiological indexes such as water potential, air temperature, relative humidity, etc.