云南热带、亚热带山地灌草丛植被特点及利用途径

灌草丛植被在云南的热带、亚热带山地广泛分布。这一植被类型主要由热带(或起源于热带)的禾草所组成，形成一个很明显的禾草草层，其上散生少数乔、灌木。现已分出5个植被亚型，12个群系和17个群丛。5个植被亚型是：热性灌草丛、干热性灌草丛、暖热性灌草丛、暖温性灌草丛和温凉性灌草丛。其中干热性灌草丛可认为是“半热带草原”或“次生热带草原”。在长期演替中，5个灌草丛可分别向5个最后的气候顶极演替。在开发利用上，山地坡度大于20˚者可发展林业，小于20˚者可发展畜牧业及其他种植业。在已划定的自然保护区(或点)内，必须严格保护，并可开展一些重要科研工作。

THE CHARACTERISTICS AND UTILIZATION OF SHRUB-GRASSLANDS IN TROPICAL AND SUBTROPICAL MOUNTAINS OF YUNNAN

Shrub-grasslands are widely distributed in tropical and subtropical mountains of Yunnan. This vegetation type consists mainly of tropical grass species (or originated from tropics), which make a very distint grass-layer, and above that a few shrubs and trees scattered. A classification system of these shrub-grasslands has already made to show that 5 vegetation-subtypes, 12 formations and 17 associations have been found now.The 5 vegetation-subtypes are hot shrub-grassland; dry-hot shrub-grassland; warm-hot shrub-grassland; warm-temperate shrub-grassland; temperate-cool shrub-grassland, among which, the dry-hot one may be recognized as semi-savanna or secondary savanna. In the long course of succession, the 5 vegetation-subtypes developed into 5 climax vegetations respectively, that is the tropical monsoon forest or tropical rain forest; river valley monsoon forest or monsoonal evergreen-deciduous mixed forest; monsoonal evergreen broad-leaved forest (through Pinus kesiya var. langbianensis forest); semihumid evergreen broad-leaved forest (through Pinus yunnanensis forest); mountainous humid evergreen broadleaved forest (through Pinus armandi forest or P. yunnanensis forest).In utilization and exploitation, it is important to bear in mind that where slope is over 20 degrees, forestry must be developed, and where it is under 20 degrees, animal husbandry and other plantations should be carried out. Areas or points already designated as reserves must be protected and many important scientific researches must also be conducted.