The New Zealand Soil Science Society conference was held in Rotorua in December 2024 and Erin McIlmurray, our Market Sector Manager - Agriculture, attended for the first time. She took away some new learnings and discovered some valuable insights.
I thoroughly enjoyed Hon. Penelope Wensley’s plenary speech on “Thinking big about soil”. The Hon. Wensley eloquently described the process of improving soil health through policy, from global strategy to regional action plans, putting into perspective the global network of passionate people influencing and implementing initiatives for positive change.
I learnt that attention to soil emerged in 2022, through agriculture and the importance of biodiversity. The elevation of soil biodiversity underpins its fundamental role in resilient and sustainable food systems. And while terrestrial micro plastic pollution is something I am familiar with, the scale of the problem being four times worse than in the sea was a shock.
While there were some confronting messages, being surrounded by passionate soil folk on World Soil Day was fantastic. The enthusiasm is contagious. I walked away with a list of ideas a mile long and I am looking forward to getting stuck in this year.
What gets measured, gets managed is a famous phrase from the well-known management guru Peter Druker. What we measure, by default becomes what we focus on. The awareness of healthy soils is growing and testing can provide insights into the effects of management practices on soil health. Hot Water Extractable Carbon (HWEC) and Hot Water Extractable Organic Nitrogen (HWEON). These two tests help support environmental stewardship and maintaining healthy soils.
HWEC measures the labile organic carbon pool in soil and provides an indication of soil health due to its high correlation with soil microbial biomass carbon and aggregate stability. This test has been well received by the market. More information can be found here.
The HWEON test has been shown to closely correlate with the nitrogen mineralisable potential of soil, which refers to the amount of nitrogen likely to be available to crops throughout the growing season, released from soil organic matter through microbial activity.
In New Zealand, we are fortunate to have soils with relatively high levels of organic matter. However, intensification of farming practices can threaten the retention of this organic matter. Certain cropping methods can negatively impact soil carbon (and nitrogen) storage, while climate factors also play a significant role. By using soil testing tools like HWEC and HWEON alongside standard soil fertility tests, farmers can adapt their practices to better retain soil carbon and improve the efficiency of fertilizer nitrogen use.
To learn more about our soil health and other tests, please contact 0508 Hill Lab (44 555 22) or email ag.csm@hill-labs.co.nz or refer to our technical notes.
