Aims: Understanding plant distribution pattern and floristic regionalization provides the basis for resource development, species introduction, diversity protection, and long-term planning. Here, the distribution pattern of wild seed plants and the diversity of genera and species in different areas of the Zhejiang Province were analyzed, and the floristic regionalization was discussed.
Method: Based on the distribution data of wild seed plants in Zhejiang, recorded in volumes 2-10 of the recently published Flora of Zhejiang (New Edition), the distribution pattern and floristic regionalization of wild seed plants in Zhejiang was conducted using statistical and analytical methods of species and genera in this study.
Results: Excluding infraspecies, there are 4,430 species of seed plants (representing 1,469 genera in 212 families) in Zhejiang Province, of which 3,344 species are native and wild (representing 1,085 genera in 190 families), including 1,405 species and 45 genera that are endemic to China. At the genus level, there are 548 genera that are widely distributed, which accounts for 50.5% of all wild seed plants in Zhejiang. The most genera are found in the Donggong Mountain area (851), the Southeast Zhejiang coastal area (822) and the Tianmu Mountain area (818) and the least in the North Zhejiang plain (only 411 genera). At the species level, the most are in the Donggong Mountain area (2,304), followed by the Tianmu Mountain and Xianxialing Mountain areas (more than 2,000 species each), and the least are in the North Zhejiang plain area (only 721 species).
Conclusions: According to the distribution of seed plants in Zhejiang, we identify four groups: widely-distributed species (904), common species (846), limited species (1,000), and area-unique species (594). Based on the distribution of 1,846 common and limited species, we recognize six distribution patterns: North Zhejiang (including 171 species), South Zhejiang (280 species), West Zhejiang (109 species), East Zhejiang (93 species), West to Southeast Zhejiang (98 species), and Northeast to Southwest Zhejiang (37 species). The others are s cattered or disjuncted in hills and mountains. According to the genera and species distribution of wild seed plants in Zhejiang and the results of previous studies on regionalization, the flora of Zhejiang is divided into two regions (East China and the Lingnan mountainous region), three subregions (Huang-Huai plain subregion, southern Zhejiang mountainous subregion and the Northern Fujian mountainous subregion), and five districts (North Zhejiang plain district, North to Central Zhejiang mountainous and hilly district, Northeast Zhejiang coastal district, South to Central Zhejiang mountainous and hilly district, and the Southeast Zhejiang coastal district).