Figure.7 Betweenness centrality of nodes in oasis transition
network during various periods
4.4 Oasis structural stability
analysis
The oasis structural stability was assessed by the average path length
for all the sub-periods in the oasis transition network. If the average
path length was longer, the transition between the oasis types was more
difficult, and the oasis had a stronger structural stability. In Table
2, the average path length of the oasis transition networks was all
shorter than 1.5 in the seven sub-periods, implying an unstable
structure of the oasis system. Additionally, the average path length of
the oasis transition network descended from 1.47 to 1.20 in 1990-2020,
which demonstrated the oasis system became increasingly unstable.
The average path length decreased by 5.44% between 1190-1995 and
1995-2000, and kept stable during 1995-2010. In this period, cropland
areas expanded significantly, and many efforts like planting. However,
the average path length decreased to 1.20 during 2010-2020, which
indicated transitions among different land types were easier and oasis
transition network was more complex.