Throughout the Saline Bush Foods project, two soil scientists have been carefully monitoring the environmental impact of the in-ground production systems – Wild Harvest and Plantation. The assumption was that improving productivity on these degraded soils would result in a positive health benefit also – the monitoring was to test that!

Dr Jolene Otway has been looking at soil carbon and nutrients, groundwater, habitat and salinity, and Dr Bede Mickan specialised in the soil DNA analysis. Their work has been brought together in a full report titled “Environmental Reporting for Saline Bush Foods Production”, with a shorter summary document, both available for download from the Katanning Landcare website.

In the Plantation site, the data indeed is showing a positive trajectory of improvement. Although there was significant disturbance to establish the site, soil carbon and other factors showed that recovery from the initial impact had occurred, and was continuing in an upward direction. Soil DNA showed a measured increase in species that are involved in carbon cycling (especially directly under the saltbush plants) and nitrogen fixation.

There was also a close relationship between soil nutrient content and the nutrient content of saltbush leaves, which varied across the site.

In the Wild Harvest site, monitoring showed that scarification was not a beneficial technique to support better growth and recovery. After an initial flush of growth fuelled by nutrients brought to the surface by the machine, the system collapsed and performed worse due to the now reduced amount of groundcover and plant biomass.

Un-scarified (control) areas showed high stability, and soil bacterial involved in carbon cycling were consistently present in higher numbers where plants are directly located.

No impact on groundwater levels by the increased production at the sites was able to be detected in the relatively short time-frame of the study.

Extensive data and analysis is provided in the full report.