Distribution, Population Structure, Regeneration Limitations, and Conservation Measures for Cunninghamia konishii Hayata in Pu Mat National Park, Vietnam

Abstract

Cunninghamia konishii Hayata, a rare conifer belonging to the family Taxodiaceae, is known from only four isolated subpopulations within Pu Mat National Park (Khe Bu, Khe Tun, Khe Ngoa, and Pu Nhong), collectively covering approximately 7,167 hectares—equivalent to just 0.008% of the park's total area. The species occurs at elevations ranging from 960 to 1,500 meters on yellow feralit soils and typically forms clustered stands on steep slopes (35–45° inclination). Field surveys recorded mature individuals with diameters at breast height (DBH) ranging from 80 to 160 cm and heights between 30 and 50 meters, with some trees exceeding 60 meters. However, regeneration is critically limited, with seedlings found only in canopy gaps and along ravines, indicating serious recruitment failure. This study examines the species’ current distribution, population structure, and ecological constraints, and proposes integrated in-situ and ex-situ conservation strategies aimed at improving natural regeneration and enhancing the long-term viability of this endangered conifer.