6. Conclusion
In this study, oasis spatial-temporal variations in Tuha Basin were
first analyzed for the further transition investigation over the past 30
years. All the oasis types increased from 1990 to 2020, and the natural
oasis expanded the most. Oasis transition processes, key land type and
oasis structural stability were then depicted using the constructed
oasis transition network. We concluded that the oasis transition
relationship among different oasis types became more complicated in 2020
than that was in 1990. Grassland, shrubland, forest and cropland changed
the most during the study period, and grassland was viewed as the key
land type due to the high out-degree, in-degree values and betweenness
centrality. The oasis structural stability calculated from the network
showing declining trend from 1990 to 2020. To explore the driving forces
of oasis changes, correlation analysis between the natural and human
factors and oasis changes was conducted using the Pearson coefficient.
Among the natural driving factors, temperature correlated positively
with natural oasis changes, and had insignificant effects on artificial
oasis. In human driving factors, population, the total power of
agricultural machinery, raw coal production, and the total agricultural
output improved the growth of shrubland and the artificial oasis;
built-up showed the most positive response to human driving factors. The
study clarified the oasis transition pattern and process, and provided
scientific reference for future oasis study and management.