Objective The purpose of this study is to investigate the environmental factors affecting soil fertility in special habitats, and to provide basis and decision-making basis for vegetation restoration and ecological management in the Dry-hot valley of Jinsha River.

Method The surface soil fertility and their influencing factors were comparatively studied by field investigation, soil collection and laboratory analysis from 47 plots in the upper, middle and lower reaches in the Dry-hot valley of Jinsha River.

Result ① The soil fertility in the upper, middle and lower reaches in the Dry-hot valley of Jinsha River was affected by climate, vegetation and other environmental factors. The soil fertility in the upper reaches was better than that in the middle and lower reaches, and the soil fertility in the middle reaches was the worst; ② The soil fertility in the Dry-hot valley of Jinsha River was significantly affected by vegetation types. The soil porosity, organic matter, total nitrogen and total phosphorus contents of natural forest were significantly (P < 0.05) higher than those of savannah, and the soil fertility of artificial forest was also better than that of savannah; ③The increase of altitude in the Dry-hot valley of Jinsha River resulted in the decrease of ambient temperature, the increase of humidity, the gradual transition of vegetation from savanna to artificial forest and natural forest, and the soil fertility characteristics such as soil porosity and nutrient content increased significantly (P < 0.05) with the increase of altitude; ④The Dry-hot valley of Jinsha River was affected by light and water, which resulted in better soil fertility in the shade slope than in the sunny slope.

Conclusion The study showed that the soil fertility in the Dry-hot valley of Jinsha River was affected by environmental factors such as different sections, vegetation types, elevation and slope direction. There were regional differences in soil fertility. Therefore, the corresponding vegetation restoration management scheme should be formulated according to the environmental conditions such as different sections, vegetation types, elevations and slope direction in the practice of vegetation restoration and ecological management in the Dry-hot valley of Jinsha River, so as to obtain better vegetation restoration benefits.