According to Table I, it can be obs

According to Table I, it can be observed that C gradually
decreases with increasing a/b, i.e. the change of
the capacitance of the probe caused by the soil water
content change is reduced. In other words, the sensitivity
of the probe decreases as a/b increases. In addition, the
nonlinear relationship C−a/b, using the method of least
squares regression fitting, shows a good power function,
C = 6.5991 · (a/b)−0.2601, with the correlation coefficient
R2 = 1, as shown in Fig.4.