不同C4植物叶片N、P质量分数变化及科、种间差异比较

为了解不同C4植物叶片中N、P质量分数的变化,对已报道的10科34种植物叶片中的N、P质量分数进行了统计和分析。结果表明:不同科、种间叶片的N、P质量分数存在差异,但呈现一定的规律性分布。N质量分数在1.5%～2.0%的植物种类最多,约占总数的29.41%。N质量分数在1.0%～1.5%和2.0%～2.5%范围内的植物数量相近,分别占总数17.65%和20.59%。而N质量分数在3.5%～4.0%和大于4.0%的范围内的植物种类很少,分别占总数的2.94%和2.91%。叶片中P质量分数在(0.75×10-3～1.25×10-3)范围内的植物数量最多,大约占总数的23.53%,而P质量分数在小于0.25×10-3的范围内植物数量最少,约占总数的2.92%。叶片N/P比值在10～15内,植物数量最多,约占总数的29.41%。不同科之间的比较发现,藜科植物叶片中N质量分数较高,达到3.33×10-2,蒺藜科和豆科植物叶片中N元素平均质量分数次之(3.0%～3.1%),最低的为禾本科,仅有1.557×10-2。叶片中P的平均质量分数在蒺藜科中达到最高,约为2.91×10-3,蔷薇科和禾本科次之,分别为2.32×10-3和1.67×10-3,最低的为莎草科,仅有0.74×10-3。藜科植物的N/P最高,达到44.85,豆科植物叶片中N/P次之,为27.45。而蒺藜科的N/P最小,为10.84。以上结果对于探讨C4植物化学计量生态学差异提供了基础统计数据。

Variations of N and P Contents in Different C4 Plant Species and Their Inter-family Differences

The contents of N and P in 34 plant species of 10 families which have been reported in some references were analysed in order to understand the variations of N and P contents in leaves of different C4 plants.Results showed that the N,P contents exhibited certain regularity though the contents were various in different species.Many plant species had moderate leaf N content ranging from 1.5 percent to 2.0 percent,accounting for 29.41 percent of the total 34 species.The numbers of plant species with N content ...