Vegetation dynamics during different abandoned year spans in the land of the Loess Plateau of China.

In this semi-arid area, many studies focused on the two-phase vegetation pattern were carried out to explore a changing vegetation trajectory on degraded land. However, this study conducted an analysis of a two-phase vegetation pattern and explored the successional vegetation trajectories in a positive succession without disturbance. In this work, 60 randomly distributed plots (1 × 1 m) were invested on four abandoned land areas (4-, 12-, 22-, and 50-year abandoned land) to determine attributes of vegetation, and soil physical and nutritional properties. It was found that vegetation distribution development went from homogeneous on 4-year abandoned land to heterogeneous on 50-year abandoned land, with a positive succession. Meanwhile, there was a significant difference in soil physical and nutritional properties for the inside and outside of vegetation patches. Vegetation patches can supply better soil physical and nutritional properties for vegetation than bare patches along the abandoned time. Vegetation diversity changes without a regular trend which may be due to the effect of environment and interspecies competition. This work picked up the slack for vegetation patterns succession research and provided a quantitative analysis approach.