南沙群岛自然区划

本文综述了自然区划的一般原则和方法，以南沙群岛为例，论述了海陆兼备的区域自然区划，但这里存在深海区的垂直带谱问题。文中提出了南沙群岛地区自然区划方案，同中国科学院的全国自然区划的五级方案衔接，在三级区域下划分２个四级区域，再细分４个五级区域。

INTEGRATED RHYSICOGEOGRAPHCAL REGIONALIZATION OF THE NANSHA ISLANDS

ccording to the hierarchic system of integrated physicogeographical regionalization in physical of China edited by Chinese Academy of Sciences(1985), the 5 grading units from high to low are great nature area, nature area, natUre region, nature sub-region and nature minor-region. The Nansha Islands is in the South China Sea Tropical Islands Evergreen Forest Nature Region (the third grade region), which belongs to the South China Tropical Humid Area (second grade region) in the Eastern Monsoon Area (first grade region). Nansha Islands area may also be divided into 2 regions of fourth grade and 4 regions of fifth grade. The two nature subregions (fourth grade region)are: I1 The Equatorial Shelf Shallow Sea and Coral Reef Nature Subregion in South Nansha Islands. I2 The Tropical Deep Sea and Limesand Islet Evergreen Forest NatureSub-region in North Nansha Islands. The four natural minor- regions (fifth grade region) are I1-1 The Coral Reef Region in South Nansha Islands. I1-2 The Equatorial Shelf Shallow Sea Region in South Nansha Islands. I2-1 The Limesand Islet Evergreen Forest Region in North Nansha Islands. I2-2 The Tropical Deep Sea Region in North Nansha Islands.A map of physicogeographical regionalization of the Nansha Islands is drawn. The principal characters of the nature sub-regions and nature minor-regions are described. And the vertical zonality from surface to bottom in deep sea is preliminarily discussed.