圆柏属常绿木本植物元素含量的季节动态

Seasonal changes of element concentrations in the leaves of Sabina

测定分析了圆柏属2种常绿木本植物叶片干物质含量、叶绿素含量及N、P、K、Na、Ca、Mg等元素含量的季节变化和元素间的关系。结果发现,两种圆柏叶片N含量与叶绿素含量正相关,反映了其一年四季的生长情况;两树种N和K含量的季节变化趋势相似,夏、秋季高于冬、春季,表明两树种夏、秋季富集的营养物质较多,与夏、秋季较高的生物量一致;而P、Ca、Mg和Na含量是冬、春季较夏、秋季高,表明圆柏属植物通过积累这些无机渗透调节剂来增强其对低温的抗性。两树种叶片对N和K同步积累,对P、Na和Mg同步积累,但在元素积累模式上也存在一定的差异,元素间的关系也要复杂得多。

The seasonal changes of dry matters, chlorophyll contents and N, P, K, Na, Ca and Mg concentrations in the leaves of S. przewalskii and S. chinensis were studied, the relations among these elements were also discussed. The results showed that N concentrations were positively correlated with chlorophyll contents, reflecting seasonal changes of growth of the evergreen woody plants of Sabina. N and K concentrations in summer and autumn were higher than that in winter and spring, indicating that two species enriched abundant nutrient matters in summer and autumn, which were identical with accumulating higher biomass in these two seasons. P, Ca, Mg and Na concentrations in winter and spring were higher than that in summer and autumn, and this indicated that two species could accumulate abundant inorganic osmotica to adapt itself to low temperature. N and K were accumulated synchronously, P, Na and Mg were accumulated synchronously, however, two species were different in the patterns of element accumulation and seasonal changes, and the relations among elements were very complicated.