In order to explore the changes of vegetation community characteristics and soil environmental factors in the 50 a plantation of Caragana korshinskii in the sqndy-hilly area of northwest Shanxi Province

the changes of growth characteristics

soil water content

soil nutrients and plant community characteristics of C. korshinskii were analyzed in 0 (abandoned land)

12

18

40 and 50 years. The results showed that: (1) With the increase of planting years of artificial C. korshinskii forest

the coverage and height of C. korshinskii increased significantly in the time gradient. Specifically

the coverage of C. korshinskii in the late planting period (40~50 years) was 1.98 times of that in the early planting period (0~12 years)

while the height was 1.48 times of that in the early planting period (0~12 years). However

the density of C. korshinskii decreased significantly with the increase of planting years

from 0.35 plants/m2 in the early planting period (0~12 years) to 0.11 plants/m2 in the late planting period (40~50 years). (2) Soil environmental factors gradually recovered with the increase of planting years of artificial C. korshinskii forest

which showed that the SOC

pH

AN

and AK increased on the time gradient

and the SW

SS

and AP decreased. The restoration degree of 0—20 cm surface soil was higher than that of 20—100 cm soil. (3) In the early stage (0~12 years)

the recovery rate of soil nutrients was significantly lower than that in the middle and late stage (12~50 years). The shrub had a significant enrichment effect on soil nutrients (0—20 cm). With the extension of the establishment time of the plantation

during the late planting period (40~50 years)

the area of islands of fertility extended to the shrub. (4) With the increase of planting years in artificial C. korshinskii forest

the soil environment improved

the species and quantity of herbaceous plants increased significantly

and the dominant species also changed

from the pioneer annual species (Artemisia dalai-lamae and Avena fatua) as the dominant species in the early planting period (0~12 years) to the dominant perennial herbaceous species (Elymus dahuricus) in the middle and late planting period (12~50 years). The natural semi-shrub (Artemisia gmelinii) invaded

and the simple artificial C. korshinskii forest changed to the complex shrub community. (5) Planting artificial C. korshinskii forest had an obvious role in promoting soil environmental factors and community diversity. Through different types of plant community and soil environmental factors of RDA constraint sorting analysis diagram

artificial forest of C. korshinskii

annual herb

perennial herb and natural subshrub and soil environmental factors (SW

soil nutrient index) showed significantly correlation. Different types of plant communities and soil environmental factors were interrelated and mutually restricted to form a relatively stable community structure. The planting of C. korshinskii forest has important reference value for community restoration and ecological environment reconstruction in arid and semi-arid areas.