The formation-types are first rearranged into four major biochoresforest, savanna, grassland, and desert . 首先把群系型重新排列成四個主要的生態區森林、稀樹草原、草地和荒漠。
Some systems for the classification of climates seek to define climatic units that will correspond to major formation-types . 一些對氣候的分類系統傾向于以相應的主要群系型來范定氣候的單位。