Soil Health - The Importance of Testing

Date: 5 Feb 2020
Author: Hill Laboratories

All life is dependent on the soil’s continued ability to provide a wide range of ecosystem functions to produce food, fibre, feed, fuel, and foundations for construction. One of the five “Pillars of Action” under the United Nations FAO Global Soils Partnership is to “promote sustainable management of soil resources for soil protection, conservation and sustainable productivity”. Every year on December 5th, World Soils Day is celebrated amongst the international soil science community, with groups actively working towards soil health.

Soil health is a product of chemical, biological and physical factors – all underpinned by carbon as “Soil Carbon transcends all three indicator categories and has the most widely recognized influence on soil quality as it is linked to all soil functions”. (UNFAO Soils Portal)

Hill Laboratories recently started offering the Hot Water Extractable Carbon (HWEC) test to our customers, as researchers have shown this test to be a good indicator of soil health due to its high correlation with soil microbial biomass Carbon and also aggregate stability.

Along with HWEC, we are now excited to additionally provide it’s partner test, Hot Water Extractable Organic Nitrogen (HWEON). The HWEON test has been demonstrated to very closely relate to the nitrogen mineralisable potential of a soil i.e. the amount of nitrogen most likely to be available to growing crops over the growing season, as released from soil organic matter by microbial activity.

In New Zealand we are fortunate to have relatively high levels of organic matter in our farmed soils, however intensification can put the retention of this organic matter at risk. Some cropping practices can be detrimental to the retention of soil carbon (and nitrogen) and climate effects are also important. Using soil test tools such as HWEC and HWEON along with the routine tests for soil fertility will help in adapting farm practices to retain soil carbon and to also be efficient in the use of fertiliser nitrogen. These two new tests are therefore helpful in environmental stewardship and promotion of healthy soil.

For more information, please view our Technical Notes or call one of our helpful Agriculture Client Services Managers.