关键词: 庐山国家级自然保护区, 球囊霉素相关土壤蛋白, 土壤因子, 丛枝菌根真菌, 根际土

Abstract: Forests in Lushan show obvious latitudinal zonality. The evergreen broad-leaved forest and evergreen and deciduous broad-leaved mixed forest are widespread in the central region of Lushan, with great significance in biodiversity and ecological services of Lushan. The dynamic of glomalinrelated soil protein (GRSP) is one of the important indices to evaluate and indicate soil quality. Exploring the distribution characteristics and influencing factors of GRSP would be helpful for the improvement of forest soil quality in Lushan. We collected rhizosphere soils of nine dominant tree species (Rhododendron simsii, Corylopsis sinensis, Lindera reflexa, Ligustrum lucidum, Ulmus pumila, Symplocos stellaris, Loropetalum chinense, Lindera glauca, Camellia cuspidate) on the north and south slopes of evergreen broad-leaved forest and evergreen and deciduous broad-leaved mixed forest in Lushan Nature Reserve. The colonization rate of arbuscular mycorrhizal (AM) fungi, spore density, total GRSP (T-GRSP) and easily extractable GRSP (EE-GRSP) contents were measured, and their relationships with soil physicochemical properties were analyzed. GRSP contents in rhizosphere were different among various dominant tree species. EE-GRSP (1.5 mg·g^-1) and T-GRSP (5.45 mg·g^-1) contents ofCorylopsis sinensis were the highest, while those (1.12 and 4.07 mg·g^-1) of Symplocos stellaris were the lowest. However, there was no difference in the ratio between EE-GRSP and T-GRSP among all the examined tree species. T-GRSP content of the same tree species was significantly higher in the north slope than in the south slope (P<0.05). The ratios of T-GRSP and EE-GRSP to soil organic carbon were 13.08% and 3.62%, respectively. Such values for Corylopsis sinensis and Lindera reflexainin the south slope were significantly higher than that in the north slope (P<0.05). Moreover, the average colonization rate and spore density of AM fungi were 35.43% and 117.2 ind·10 g^-1 (dry soil), respectively. In addition, GRSP contents were significantly positively correlated with total nitrogen, soil organic carbon, soil moisture, and colonization rate of AM fungi (P<0.01). The AM fungi colonization and GRSP distribution were detected in all the nine dominant tree species in Lushan. Moreover, GRSP content was closely related to multiple soil factors. These results indicate that GRSP can be used as an effective indicator to reflect forest soil quality in Lushan. Our findings supplement and improve the evaluation index system of forest soil in Lushan.

Key words: Lushan National Nature Reserve, glomalin-related soil protein, soil factor, arbuscular mycorrhizal fungi, rhizosphere soil.