15 enthusiasts of citizen science (out of ~8000 reached by Facebook Ad) came on 16 August 2015 to Anstey Keane Bush Forever Site (number 342) to participate in the open research on how disturbance affects soil quality and plant diversity. The event was carried out in the form of a bushland hike, led by the president of Murdoch Branch that is me 🙂 . Participants were assigned to five teams. Each team collected one soil sub-sample from three different locations:
1. Invasive plants only,
2. Invasive and natives,
3. Orchids and natives only
The soil analysis cost us nearly $1200 which is 85% of the grant. The content of total Nitrogen, Phosphorus + heavy metals: Cadmium, Molybdenum, Cobalt, Selenium, Lead, Chromium & Arsenic in the soil we tested. At some point in time we will also have an access to data on soil microbes from Microblitz Team. The soil results are already available online at Data.
If you look at the concentration of the heavy metals in the soil you immediately see the pattern of decreasing concentration as we move away from the invaded site. One can rethink the role of weeds in the disturbed areas. The invasive species were the only plants that could tolerate a high bush soil disturbance level along the busy Anstey Road. The concentration of the heavy metals were relatively high but reached no dramatic ecological investigation levels according to Assessment Levels for Soil, Sediment and Water guideline issued in 2010 by Department of Environment and Conservation (DEC). Nonetheless as low as 25um/dL of lead (Pb) in blood can lead to Nausea, vomiting & encephalopathy (headache, seizures, ataxia, obtundation). As the heavy metals tend to accumulate in plant tissues too growing vegetable along the Anstey road is not recommendable.
Not surprisingly Total Nitrogen and Total Phosphorus were the highest in the most disturbed soil as these vital micro-nutrients, that build Plant’s DNA & Cells, are being allocated across much wider spectrum of living organisms in the undisturbed ecosystem: