Keeping it in Kin Kin Project
by Rachel Lyons, Business Development Manager, Noosa & District Landcare
For the last 18 months, Noosa Landcare has been rolling out phase 1 of the Keeping it in Kin Kin Project. The project objectives include protecting the water quality and soil resources of the Noosa River system and Kin Kin Catchment.
To be the most efficient in our attempts to reduce soil erosion in the catchment, we needed to know precisely where the erosion hot-spots are, the scale of erosion we were dealing with and which erosive processes are contributing most significantly. In partnership with the Noosa Biosphere Reserve Foundation, Noosa Council, Healthy Land and Water, Noosa Parks Association, Noosa Integrated Catchment Association, Country Noosa, The Thomas Foundation and the Kin Kin community, funds were raised to undertake an analysis to answer these questions.
The technology that our steering committee selected to help answer our questions was LIDAR technology or Light Detection and Ranging topographic data. LIDAR is a remote sensing method where pulsed laser is used to measure the distance from the laser sensor (in a plane or drone) to the earth, to create accurate digital elevation models. Our analysis involved the comparison of a 2008 dataset to a 2015 dataset to identify areas that have had elevation change, both positive and negative, during that time. This analysis identified areas where soil loss and soil deposition had occurred.
The overall result of the analysis was staggering. The scale of erosion was greater than we had estimated for the relatively small (22,000ha) catchment. Over 2.4 million tonnes of soil was calculated to have been mobilised between 2008 and 2015. The equivalent of almost 191,284 large dual-axel soil delivery trucks of soil or 765 Olympic sized swimming pools filled with soil. This valuable soil is moving through our farms, down the catchment and into the Noosa River system.
We now have a better understanding of the sites where we are seeing the greatest soil movement occurring and the types of erosive processes involved. Landslips, gully and riparian erosion are the predominant processes occurring, much of which is the legacy of vegetation clearing of very steep slopes at the turn of last century and continuing unstable gully and riparian areas.
In addition to the LIDAR analysis, the Keeping it in Kin Kin project also included an on-ground landslip and riparian erosion restoration project on a cattle grazing property in Wahpunga Creek. The project successfully planted 2,200 trees and excluded cattle from unstable riparian areas by fencing.
The final major component of the project identified the value of keeping our current riparian vegetation in good condition, in particular from the threat of the highly invasive and ‘transformer’ weed, the Cat’s Claw Creeper Vine (Macfadyena unguis-cati). In partnership with Noosa Council and Healthy Land and Water, we surveyed over 80 lineal kilometres of creek line on foot, and over 470 hectares of rainforest, to map the extent of the nefarious vine. The survey was undertaken so that our efforts to control the weed into the future are the most targeted and efficient. Using a triage approach, we have planned and mapped our target areas for physical and biological weed control efforts.
If you want to learn more about the Keeping it in Kin Kin project and the results of the surveys and plans, we are holding a community workshop in Kin Kin on the 23rd April 2018 from 5.30pm. A light supper will be provided and we will have copies of maps and reports available to peruse and discuss. Bookings can be made via our office – firstname.lastname@example.org or by phoning 5484 2468.
Photo: Project Steering Committee, November 2017 – on a site visit to an on-ground erosion remediation demonstration site.