Vegetation community characteristics and edaphic factors in 40 years fire protection of dwarf deciduous dipterocarp forest, Phae Muang Phi Forest Park, Phrae Province

Abstract

The study of plant community characteristics related to environmental factors may help emphasize of forest ecosystem management. This study is aimed to study the structure and species composition of trees based on edaphic factor gradient in the fire prevention dwarf deciduous dipterocarp forest, Phae Muang Phi forest park, Phrae province. Fifteen plots with size 20 m x 20 m based on purposive sampling were set up. Species composition and soil nutrients were collected to analyze the relationship between plant community and soil factors. The result showed that, 60 species 54 genera and 28 family of all 1,457 trees. The cluster analysis showed 3 sub-community: Shorea obtusa community (SOC), Shorea siamensis community (SSC), and Suregada multiflorum community (SMC). The SOC showed that 34 species 32 genus from 19 family and species diversity index was 1.70, the important species such as Shorea obtusa, Dipterocarpus obtusifolius, and Shorea siamensis. The SSC showed that 34 species 31 genus from 18 family and species diversity index was 2.59, the important species such as Shorea siamensis, Pterocarpus macrocarpus, and Vatica harmandiana. The SMC showed 49 species 43 genus from 24 family and species diversity index was 3.13, the important species such as Suregada multiflorum, Cratoxylum cochinchinense, and Phanera bracteate. The dominant species of SOC positively determined by phosphorus. While, species composition of SSC community was determined by clay texture and soil nutrients such as potassium, magnesium, calcium, nitrogen, and organic matter. Simultaneously, the dominant species of SMC community were controlled by sand texture, and it had lowest nutrients deposition compare to others. The result suggested that after long-term of forest fire protection, causing the trees species composition changed from the dwarf deciduous dipterocarp forest based on increasing of soil nutrient accumulation. Thus, fire protection leads to high soil nutrient accumulative which induced high establishment of evergreen species into the community.

Keywords: species diversity; forest fire preventing; plant community changing; protected area