CAJ | 학술논문

对植物区系起源、分布和迁移过程的分析对我们更好地理解植被的发生、演化和分布具有重要意义.利用大尺度的植物区系分布信息,结合地理信息系统(GIS)空间分析和二元相关性统计分析,探讨了澜沧江流域(云南段)种子植物区系成分的纬度分布格局及河谷的“通道效应”.结果表明,研究区域内热带植物区系成分占主导地位,而温带区系所占比重则仅为1/3左右,故表现出明显的热带区系性质.其中,比较重要的区系成分主要包括热带亚洲分布(T7)(21.2%)、泛热带分布(T2)(16.5%)和北温带分布(T8)(11.7%)等.区系过渡性随着纬度的升高,从南到北呈先增强后减弱的单峰分布格局,纬度26o N左右出现峰值.这可能与其地处低纬度地区、紧邻古热带植物区的区系地理位置和南-北方向上海拔梯度有关.温带区系成分所占比重随着纬度的升高呈明显递增趋势,而热带区系成分所占比重则呈明显递减趋势,这与不同区系成分的生态特性和纬度梯度上的热量递减格局是一致的,同时也可能与澜沧江河谷在植物区系迁移过程中所发挥的“通道效应”有关.中国特有分布成分所占比重与表征地形复杂度的海拔高差之间存在明显的正相关关系,这可能意味着特有植物类群的形成和演化与地理隔离机制有关.
대식물구계기원、분포화천이과정적분석대아문경호지리해식피적발생、연화화분포구유중요의의.이용대척도적식물구계분포신식,결합지리신식계통(GIS)공간분석화이원상관성통계분석,탐토료란창강류역(운남단)충자식물구계성분적위도분포격국급하곡적“통도효응”.결과표명,연구구역내열대식물구계성분점주도지위,이온대구계소점비중칙부위1/3좌우,고표현출명현적열대구계성질.기중,비교중요적구계성분주요포괄열대아주분포(T7)(21.2%)、범열대분포(T2)(16.5%)화북온대분포(T8)(11.7%)등.구계과도성수착위도적승고,종남도북정선증강후감약적단봉분포격국,위도26o N좌우출현봉치.저가능여기지처저위도지구、긴린고열대식물구적구계지리위치화남-북방향상해발제도유관.온대구계성분소점비중수착위도적승고정명현체증추세,이열대구계성분소점비중칙정명현체감추세,저여불동구계성분적생태특성화위도제도상적열량체감격국시일치적,동시야가능여란창강하곡재식물구계천이과정중소발휘적“통도효응”유관.중국특유분포성분소점비중여표정지형복잡도적해발고차지간존재명현적정상관관계,저가능의미착특유식물류군적형성화연화여지리격리궤제유관.
Floristic origin, distribution and migration may have important implications in understanding the origin and formation and evolution of local vegetation. In this study, we examined the latitudinal patterns of floristic elements of seed plants in Lancang river in Yunnan and the river's corridor effects through spatial analysis and Pearson correlation analysis. Our results showed that tropical elements predominated over others, and the proportion of temperate elements was only around one third, suggesting strong topical characters of the flora in the studied area. The important elements mostly included elements from Tropical Asia (21.2%), Pantropic regions (16.5%) and North temperate regions (11.7%). With the increase of latitude, floristic transitions increased and then decreased, and reached its peak around 26oN latitude. It was consistent to its biogeographic location adjacent to ancient tropical regions and topographic patterns. With the increase of latitude, an increasing trend can be observed on the proportions of temperate elements, while those of tropical elements showed contrary patterns, which may be strongly correlated with their different ecological characters, decreasing trend of energy on the latitudinal gradient and the river's corridor effects. There were strong correlations between the proportions of the elements endemic to China and altitudinal range, which may imply that the formation of endemic plants may strongly correlate with local geographic isolations.