西藏及其东南地区被子植物与其不同生活型的果实类型分析

Fruit Types of Angiosperm and Their 4 Life Forms in Tibet and Its Southeastern Region

统计了分布在西藏自治区的被子植物及各生活型果实的类型及比例,并与藏东南地区做了比较。结果如下,西藏自治区果实以蒴果为主(占37.74%),其次为瘦果、坚果、浆果等;干果的比例远远大于肉果;不同生活型的果实类型谱差异较大,乔木中核果的比例最高,藤本中浆果比例最高,灌木中瘦果比例最高,草本中蒴果占优势;4个生活型中,肉果的比例乔木为最高,其次为藤本、灌木、草本。藏东南地区植物的果实类型也以蒴果为主,其次为瘦果、浆果、核果等;藏东南乔木中核果比例最高,藤本中浆果比例最高,灌木和草本植物以蒴果占优势;乔木肉果的比例最高,其次为藤本、灌木、草本。藏东南肉果比例大于全藏区,而干果比例则相反。果实类型的这些性状特征与各自的环境相适应,是植物长期适应自然环境的进化结果,该研究对于理解植物果实对生态环境的长期适应进化具有一定的意义。

This article calculated the percentages of different fruit types of total angiosperms （5810 species, 28 varieties） and their life forms （trees, shrubs, herbs and lianas） distributed in Tibet and southeastern Tibet. The results showed that in Tibet capsule is the dominant fruit type （37.74%）, followed by achene, nut and berry. The percentage of dry fruits is far bigger than that of fleshy fruits in Tibet. There are great variations in 4 life forms in fruit type spectrum. Drupe is dominant in tree, berry in liana, achene in shrub, and capsule in herb. Tree possesses the greatest percentage of fleshy fruit in 4 life forms, followed by liana, shrub and herb. In southeastern Tibet, capsule is also the dominant fruit type （37.54%）, followed by achene, berry, drupe, nut and caryopsis. The larger differences occur among the percentages of various fruit types. Drupe is dominant in tree, berry in liana, capsule in shrub and in herb. In the 4 life forms tree .possesses the largest percentage of fleshy fruits followed by liana, shrub and herb. The percentage of fleshy fruits is higher in southeastern Tibet than in the whole Tibet, and on the contrary, dry fruits is not. Such fruit characteristics are adapted to their environment and are results of long-term evolution. This study can help us in understanding a long term adaptation and evolution of fruits to their ecological environment.