Abstract:

We analyzed the soil nutrient dynamics at different vegetation successional stages of Three Gorges reservoir area by space-time substitution. The results showed that the soil pH decreased with the development of positive vegetation succession and presented acidic property. The contents of soil organic matters and available phosphorus increased with the progress of positive vegetation succession. The change of soil organic matters was evergreen broad-leaved forest> coniferous forest> deciduous broadleaved forest> shrub > coniferous forest, while the change of hydrolyable nitrogen was coniferous forest> shrub> coniferous forest> deciduous broadleaved forest> evergreen broad-leaved forest. The contents of organic matters, hydrolytic nitrogen and available phosphorus appeared obvious accumulation in the surface layers of the soil at different vegetation successional stages. Correlation analysis indicated that there were extremely significant correlation between organic matter, hydrolytic nitrogen and available phosphorus which had extremely significantly negative correlative with soil layers. The different vegetation stages had extremely significantly negative correlation with soil pH and hydrolytic nitrogen, but had significantly positive correlative with available phosphorus.

Key words: Three Gorges reservoir area, vegetation succession, soil nutrient