陕北沙地3种典型灌木根木质部解剖结构及水力特性

应用生态学报

陕北沙地3种典型灌木根木质部解剖结构及水力特性

艾绍水¹,李秧秧^2,3**,陈佳村³,陈伟月^1

(¹西北农林科技大学林学院, 陕西杨凌 712100; ²西北农林科技大学水土保持研究所，陕西杨凌 712100； ³中国科学院水利部水土保持研究所，陕西杨凌 712100)

出版日期:2015-11-18 发布日期:2015-11-18

Root anatomical structure and hydraulic traits of three typical shrubs on the sandy lands of northern Shaanxi Province, China.

AI Shao-shui¹, LI Yang-yang^2,3, CHEN Jia-cun³, CHEN Wei-yue^1

(¹College of Forestry, Northwest A&F University, Yangling 712100, Shaanxi, China; ^2Institute of Soil and Water Conservation, Northwest A&F University, Yangling 712100, Shaanxi, China; ^3Institute of Soil and Water Conservation, Chinese Academy of Sciences and Ministry of Water Resources, Yangling 712100, Shaanxi, China)

Online:2015-11-18 Published:2015-11-18

摘要/Abstract

摘要： 比较了陕北沙地沙柳、柠条和沙棘3种典型灌木不同土壤深度(0～20和30～50 cm)根木质部解剖结构和水力特性.结果表明：沙柳具有较高的叶水势，根木质部导管平均最大直径(d_max)、平均最小直径(d_min)、平均导管面积(A_lum)以及导管面积占木质部面积比例(A_ves/A_xyl)显著高于柠条和沙棘，根导管密度(VD)与沙棘相当但显著高于柠条；沙柳根的比导水率分别为柠条和沙棘的5.0和2.8倍；沙柳根栓塞脆弱性指数与柠条根相当，但显著高于沙棘根.表明沙柳属耗水型水分利用策略，而柠条和沙棘属节水型水分利用策略，且柠条更耐旱.3种灌木在2个土层深度的d_max、d_min和A_lum无显著差异，但30～50 cm土层根VD和A_ves/A_xyl显著高于表层；30～50 cm土层根比导水率显著高于表层根，但脆弱性指数小于表层根，深层根具有高的水分传输效率和低的水力脆弱性.

Abstract: Root xylem anatomical structure and hydraulic traits of three typical shrubs, i.e., Salix psammophila, Caragana korshinskii and Hippophae rhamnoides, within two soil layers (0-20 cm and 30-50 cm) were compared. The results showed that S. psammophila had a higher leaf water potential than C. korshinskii and H. rhamnoides, the average maximum and minimum lumen diameter (d_max and d_min, respectively), the average lumen area of vessels (A_lum) and the ratio of lumen area of all vessels to xylem area (A_ves/A_xyl) in S. psammophila roots were also significantly higher than those in C. korshinskii and H. rhamnoides, and the root vessel density (VD) in S. psammophila was the same as that in H. rhamnoides but significantly higher than that in C. korshinskii. Root hydraulic conductivity in S. psammophila was 5 times of C. korshinskii and 2.8 times of H. hamnoides. The vulnerability index in S. psammophila roots was similar to that in C. korshinskii but higher than that in H. hamnoides. S. psammophila belonged to a waterspending species, whereas both C. korshinskii and H. rhamnoides were watersaving species, and C. korshinskii was more droughtresistant than H. rhamnoides. There was no difference of d_max, d_min and A_lum between roots in two soil layers, but roots within in the 30-50 cm soil layer had larger VD and A_ves/A_xyl. The root specific hydraulic conductivity within the 30-50 cm soil layer was significantly higher than within the surface soil layer, whereas the vulnerability index within the 30-50 cm soil layer was smaller, indicating roots in deep soil layers had higher hydraulic transport efficiency and lower hydraulic vulnerability.

艾绍水1,李秧秧2,3**,陈佳村3,陈伟月1. 陕北沙地3种典型灌木根木质部解剖结构及水力特性[J]. 应用生态学报.

AI Shao-shui1, LI Yang-yang2,3, CHEN Jia-cun3, CHEN Wei-yue1. Root anatomical structure and hydraulic traits of three typical shrubs on the sandy lands of northern Shaanxi Province, China.[J]. Chinese Journal of Applied Ecology.