Sonneratia ovata is an important tree species for ornamental, economic, ecological, and medicinal value and is identified as an endangered species. There are very few studies on the reproductive traits, genetic diversity, and population structure of S. ovata. Therefore, it is urgent to accurately understand its genetic background and reproductive status in order to better conserve and manage S. ovata. S. ovata has a mixed mating system, is partially self-compatible and needs pollinators, according to the outcrossing index, pollen–ovule ratio, pollination treatment results and outcrossing rate. Natural populations maintained high outcrossing coupled with inbreeding and low genetic diversity (H_e = 0.215), and the population DC was regarded as the center of genetic diversity. The Mantel test showed that there existed a positive correlation between geographic and genetic distance among populations, which was in line with the IBD model. Molecular variance was largely confined to within-population differences (75.4%), while inter-population differences accounted for 24.6%. Structure and PCoA analysis supported the UPGMA cluster. This study is the first to investigate reproductive traits, genetic diversity, and population structure through SSR. The results provide a scientific basis for cross breeding, conservation, and management of this species. In future, it is necessary to increase relevant research (human, environment, habitat factors, etc.) to better protect and utilize this species.

Soil fungi play vital roles in the forest soil ecosystems through the nutrient cycle and organic substance decomposition, so the distribution of fungi at different altitudes has attracted increasing attention. However, their abundance, diversity, and community structure at different altitudes in temperate deciduous forests have rarely been studied. In this study, the fungal communities around two dominant trees (Quercus aliena var. acutiserrata and Carpinus turczaninowii Hance) in temperate deciduous forests at different altitudes (low altitude, medium altitude, high altitude) in the Taihang Mountains were identified via Illumina high-throughput sequencing according to the UNITE database. The soil chemical properties (soil pH value, soil available potassium, alkaline hydrolyzed nitrogen, soil available phosphorus contents, soil total nitrogen, and carbon contents) were also measured. The results revealed that the dominant genera around the tree species were Russula, Tylopilus, Sebacina, Saitozyma, Mortierella, Amanita, and Descolea. The highest relative abundance of fungi occurred at the lowest altitude. The species richness index and diversity index of fungi around Carpinus turczaninowii at low altitudes were the highest. The soil pH, available potassium content, and alkaline hydrolyzed nitrogen content played a crucial role in the composition and diversity of the fungal communities at different altitudes. Therefore, soil physicochemical properties were the important factors in forming fungi composition and diversity at different altitudes in the temperate forest.