关键词: 新疆杨, 美青杨, 防护林体系, 比叶面积, 叶干物质含量

Abstract: Taking three poplar species(Populus alba var. pyramidalis Bge., two clones (93-8-6, 3-69) of  Populus deltoides ×Populus cathayana)  as the research object, this paper determined leaf traits of the three kinds of poplar, analyzed the correlation among leaf traits, such as leaf area, leaf dry matter content, etc., and explored the adaptability of three poplar species to Ulan Buh Desert. The results showed that: ① The rank of leaf area, leaf length, leaf width, leaf perimeter, leaf length and width ratio were Populus deltoides×Populus cathayana 93-8-6>Populus deltoides×Populus cathayana 3-69>Populus alba var. pyramidalis Bge., leaf factor was Populus alba var. pyramidalis Bge.>Populus deltoides×Populus cathayana 93-8-6> Populus deltoides×Populus cathayana 3-69. ② There were significant differences in specific leaf area and leaf dry matter content (P<0.05) among the three species. The specific leaf area of Populus deltoides×Populus cathayana 93-8-6, Populus deltoides×Populus cathayana 3-69 and Populus alba var. pyramidalis Bge. were 20.570±1.506, 17.562±2.827 and 13.347±0.824 m2·kg-1, respectively. The leaf dry matter content of three species were 220.748±4.493, 246.015±7.594 and 299.431±6.011 mg·g-1, respectively. ③ The specific leaf area was significantly and negatively related to the leaf dry matter content (P<0.05), which displayed an exponential function relationship (y=ae-bx). The dry leaf weight was significantly and positively related to the leaf area(P<0.05), which displayed a power function relationship (y=axb ). The dry leaf weight was significantly and negatively related to the specific leaf area(P<0.05), which displayed a linear function relationship (y=-ax+b). The adaptability to the infertility and drought was well reflected by specific leaf area and leaf dry matter content. Populus alba var. pyramidalis Bge. showed better adaptability to the infertility and drought environments in Ulan Buh Desert, so the proportion of Populus alba var. pyramidalis Bge. in the restoration of protection forest should be increased in Ulan Buh Desert Oasis.

Key words: Populus alba var. pyramidalis Bge., Populus deltoides×Populus cathayana, shelter forest system, specific leaf area；leaf dry matter content