Classification of T aiwan forest vegetation

Aim We identify the main forest vegetation types in T aiwan, provide their formal definitions and describe their species composition, habitat affinities and distribution. Location Taiwan. Methods A data set of 9822 vegetation plots with environmental characteristics recorded in the field or derived from digital maps in GIS was compiled from historical literature and an extensive field survey. Using expert knowledge, 6574 of these plots were used to build a classification into broad vegetation types. The units of the resulting classification were formally defined using a C ocktail determination key, which can be used for the automatic assignment of new vegetation plots to these vegetation types. Results Twelve vegetation types of zonal forests and nine types of azonal forests were distinguished. Zonal types in the subtropical region, from high mountains to foothills, are J uniperus subalpine coniferous woodland, A bies– T suga upper‐montane coniferous forest, C hamaecyparis montane mixed cloud forest, F agus montane deciduous broad‐leaved cloud forest, Q uercus montane evergreen broad‐leaved cloud forest, M achilus– C astanopsis sub‐montane evergreen broad‐leaved forest, P hoebe – M achilus sub‐montane evergreen broad‐leaved forest and F icus – M achilus semi‐evergreen foothill forest. Zonal types in the tropical region, from high mountains to foothills, are P asania – E laeocarpus montane evergreen broad‐leaved cloud forest, D rypetes – H elicia sub‐montane evergreen broad‐leaved forest, D ysoxylum– M achilus foothill evergreen broad‐leaved forest and A glaia – F icus foothill evergreen broad‐leaved forest. Azonal types are I llicium – C yclobalanopsis tropical winter monsoon forest, P yrenaria – M achilus subtropical winter monsoon forest, D iospyros – C hampereia tropical rock‐outcrop forest, Z elkova– Q uercus subtropical rock‐outcrop forest, P inus successional woodland, A lnus successional woodland, T rema– M allotus successional woodland, S caevola– H ibiscus seashore woodland and K andelia mangrove. Conclusions The diversity of forest vegetation in T aiwan is strongly structured by the temperature and moisture gradient. Along the temperature gradient, five altitudinal zones can be recognized. Azonal forest types develop at sites affected by the winter monsoon, on steep slopes, rocky soils, in seashore saline habitats and in places disturbed by fire, landslides and human activities. Zonal vegetation contains a higher ratio of endemic and P acific species and occurs in wetter habitats, whereas azonal vegetation contains co‐existing species from different regions and usually occurs in drier habitats.