Summer Soil Sampling – Natural Capital Accounting Project Update

This summer the Perth NRM team have been out soil sampling at properties participating in the Natural Capital Accounting (NCA) project.

Two properties were visited in recent weeks – one agroecological system in Kojonup, and one mixed livestock and horticulture enterprise in Manjimup.

In the agroecological system, which is also Certified Organic, the landholder incorporates regenerative agriculture practices, focussing on maintaining ecological balance on the property through allocated conservation areas, landscape rehydration work, mosaic-style paddocks that fit within the natural topography of the landscape, and tree plantations for carbon capture and storage.

The mixed horticulture and livestock producer in Manjimup runs cattle on pastures and silage and has an avocado plantation with pockets of remnant vegetation on the property. A mixed species pasture crop was trialled last year, and will be trialled again this year with leftover seed.

Both landholders have a similar ethos, centred on continual soil health work, nutrition and general sustainable land stewardship.

Soil sampling consists of collecting both top and sub soil samples for laboratory chemical analysis.

The team also conduct a Rapid Soil Assessment (RSA) – an in-paddock visual assessment of the soil condition and functionality which includes scoring groundcover, texture (Bolus test), pH, aggregate structure, porosity, slacking and dispersion.

Getting out on farm to conduct the Rapid Soil Assessments has proven to be a wonderful opportunity to see the vast range of soil types across different landscapes, across paddocks, and the different moisture levels sustained in the different subsoils. Soils ranged from gravelly sandy duplexes, to typical Wandoo duplex loams, brown deep sands and sandy clays.

The relationship of management practices to different soil characteristics, such as productivity and resilience, is often contested due to the complex, dynamic nature of agriculture.

No accepted standard has been yet developed that accounts for soil health, but the NCA project expects that extensive agronomic expertise and a new focus on national and state-based soil strategies will yield a practical solution.

This project is providing an opportunity to trial new methods and technologies for on-farm natural capital measurement, providing a systematic and efficient assessment process, that will reduce the cost of on-farm data collection and compilation over time.













Perth NRM acknowledge and appreciate the support of all project partners, supporters, funding bodies and sponsors.