LiDAR measurements and intensive water quality monitoring at gully outlets ? -What is the best way to sample and assess the soil / sediment material physicochemical and spatial variability to an acceptable confidence and rigor ? What statistical and modelling methods could be employed to do this ? - What is the best way to compare techniques in a scientifically rigorous manner requiring replication and controls ? How will inter-gully variability and seasonal variability be incorporated into any assessment of technique assessment ? - Developing locally specific pioneer species for the effective gully restoration .
These outcomes are directly relevant to the design and implementation of the BMIP for the treatment of large scale alluvial gullies .
6.2 Current adoption estimates
There is considerable uncertainty in the knowledge of current adoption of improved management practices in grazing lands in the GBR catchments , including the Burdekin Region , largely due to poor spatial coverage of landholder surveys . The primary dataset is from the Paddock to Reef Program which reports adoption annually but only for a portion of the regionError ! Reference source not found .. This data is spatially extrapolated in the Source Catchments model to provide an estimate of management practice adoption across the Region by correlating it with remotely sensed ground cover data and therefore is important for the load estimates . As at 2014 , it was estimated for the BBB catchment that the following areas were in A and B class management practices :
• Pasture management : 9 %
• Riparian management : 44 %
• Gully management : 24 %
Modelling scenarios were completed in 2014 to estimate the sediment reduction outcomes from shifting a major of grazing lands in the region to A or B class practices ( reported in Waterhouse et al . 2016 ). The estimated reductions are shown in Figure 22 and indicate that a reduction of 31 % and 29 % in TSS load is predicted by shifting to 100 % A and B class practices respectively ( counting all erosion sources ). This highlights the need to go beyond the management practices in the Paddock to Reef Water Quality Risk Framework to the meet end of catchment load reduction targets defined for the Burdekin Basin or the BBB catchment more specifically ( see Brodie et al . 2016 adopted in the Burdekin WQIP , NQ Dry Tropics 2016 ).
Figure 22 . Modelled scenarios of TSS loads from management practice changes in grazing lands . Derived from Source Catchments 2013 baseline estimates , DNRM 2015 .
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