Figure 30 . presents the TSS and TN data collected at the control and treatment sites over the last five years . The pre-treatment data allows additional statistical analysis to be performed to evaluate the effect of the treatment . The results from 2019-20 showed that there was a statistically significant improvement in the concentration of TSS and TN at this site following the implementation of the hillslope treatments . This has also been associated with a large reduction in runoff as well as TSS and TN loads at the treatment site . These improvements have come via mechanical intervention on the hillslope which has starved the active gully of runoff ( albeit in a below average rainfall year ). A comparison of the TSS concentration data for the 2020-21 wet season showed that the TSS concentrations were significantly lower at the treatment site compared to the control site ( p < 0.001 ) ( Figure 30 . A ). Overall , however , despite the first year after treatment looking like the treatment at Strathbogie was effective , following the second year , there is no statistical difference in the TSS values at the treatment site ( p = 0.962 ).
73