论文部分内容阅读
以I-69杨(Populus deltoides Bartr.cv.‘Lux’)为研究对象,观测了不同冠层的小气候特征、叶片光合特性、光合叶面积和营养元素,并对不同冠层叶片生长状况作综合评价。结果表明,I-69杨光合特性在7、8月要好于5、9月,叶片净光合速率、平均单叶面积和单层叶面积都是冠层Ⅲ>冠层Ⅱ>冠层Ⅰ;不同冠层叶片营养元素含量随月份不同而发生变化,氮含量和磷含量从6月至10月整体上呈下降趋势,钾含量在8月前呈上升趋势,到8月后逐渐下降,钙含量则从6月至10月呈上升趋势;距离综合评价法算得冠层Ⅰ、Ⅱ、Ⅲ的相对接近度依次为0.163、0.625和0.785,表明不同冠层叶片生长状况差异显著,即冠层Ⅱ、Ⅲ叶片生长状况明显优于冠层Ⅰ。
The I-69 Populus deltoides Bartr.cv.’Lux ’was used as the research object to observe the microclimate characteristics, photosynthetic characteristics, photosynthetic leaf area and nutrient elements of different canopies and to make a comprehensive analysis of the growth status of different canopy leaves Evaluation. The results showed that the photosynthetic characteristics of I-69 were better than those of May and September in July and August, and the net photosynthetic rate, average single leaf area and single leaf area of canopy were in the order of canopy III> canopy II> canopy I; The content of nutrient elements in canopy leaves varied with the month. The content of nitrogen and phosphorus decreased from June to October in total. The content of potassium increased until August and gradually decreased after August, while the content of calcium decreased From June to October, the relative trend of canopy Ⅰ, Ⅱ and Ⅲ was 0.163, 0.625 and 0.785 respectively, which indicated that there were significant differences in the growth status of different canopy leaves, that is, canopy Ⅱ, Ⅲ Leaf growth was significantly better than canopy Ⅰ.