significant difference was in the percentage cover between the control and treatment sites on the gully floor / channel ( p < 0.001 ).
The land condition at the treatment site improved from being 93 % ‘ D ’ Condition and 7 % ‘ C ’ Condition in April 2019 , and is now 6 % B condition , 81 % C condition and only 12 % in D condition . Land Condition includes metrics such as species diversity , litter and grass basal area . Therefore , despite reasonably good cover and biomass at this site , the dominance of the pasture species Indian couch reduces the overall long term land condition at this site .
( A ) ( C )
( B ) ( D )
Figure
25 . Mt Pleasant Treatment gully site setup ( A and B ). The same system was set up at the control site . ( C ) is the control site during an event in March 2021 and ( D ) is the treatment site in March 2021 .
In 2019-20 , the median TSS value at the Mt Pleasant control site was 60 mg / L , and at the treatment site it was 48 mg / L . The median TN concentration was ~ 1,408 ug / l at the control site and ~ 1,397 ug / l at the treatment site . This is also lower than the median for most other sites ( Figure 26A ). This was the lowest median sediment concentration of any of the study sites ( Figure 17 ). In 2020-21 , the values increased slightly at both the treatment and control site . These are still extremely low median TSS values for gully sites , and interestingly there was still not significant difference between the control and treatment sites in 2020-21 for either TSS ( p = 0.0.118 ) or TN data ( p = 0.583 ), despite the large initial ponding and backwatering that was created by the treatment structures . The most surprising result was how low the TSS concentrations were at the control site that had not been treated . This lack of difference in the TSS and TN data may be due to the relatively good condition that the catchment is in relative to other sites , as the
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