We are collaborating with Plant & Food Research, AgResearch, the University of Waikato, the University of Auckland, and Auckland University of Technology to better understand soil health and resilience. In the field we have sampled and are analysing more than 150 different soil profiles (many down to more than 60 cm deep) from land use comparisons and long-term experiments. We are investigating how land use affects changes in soil carbon and soil chemistry and how those in turn affect other soil properties such as soil aggregation and microbial activity. In collaboration with the S-map Next generation Endeavour funded project, we are researching how a soil’s physical condition affects soil hydrology and soil function. Recent work undertaken in the Waikato region has compared pasture and maize cropping on a range of soil orders, e.g. Allophanic, Gley, Granular, and Ultic soils. Different soils have different properties and intensification affects these soils differently (Figs 1 and 2). These studies will allow us to better measure land use intensification effects on different soils, particularly below the topsoil where soil health effects have typically not been measured.
Māori research in this programme is focused on developing a Māori perspective of soil health by working with a large range of collaborators and partners, including Māori organic growers, land-owners (e.g. Trusts, Incorporations), iwi/hapū groups, Government, Tumu Paeroa, communities and schools, Māori knowledge experts (e.g. koroua, kuia, tohunga), and Maori scholars working in this area. Our findings show that soil has a strong Māori ancestry, connecting to Polynesian migration, knowledge, history, settlement, and gardening and we have found hundreds of soil names locally and nationally. Māori gardeners have at least 60 names for types of soil, for example, onehunga is sea sand, keretū is clay, and tuatara wawata is brown friable fertile soil suitable for kumara (also see Table 1 below).
Table 1. Examples of Māori soil classifications and interpretations
|Māori soil classifications and interpretations|
|Onematua||Loam, fertile soil of silt and sand containing humus||Parakiwai||Silt, sediment from flood|
|Onemata||Dark fertile soil||Kere, Hāmoamoa||Clay|
|Oneone||Sand||Uku||White clay used for soap and pottery|
|Taipū, Tāhuahua||Sand due, sand hill,||Keretū||Heavy clay|
|Kenepuru||Fresh alluvial deposit, silt, muddied||Kākaramea||Red clay, coloured with ochre|
Belief systems and values provide a basis for explaining soil health from a traditional and historical perspective. These values still resonate strongly today, and Māori position themselves as being part of the soil ecosystem with strong links between soil health, human well-being, and healthy foods. Some of the core values and principles generated from this work to understand Māori soil health perspectives, include: Mana, Mauri, Mahinga kai, Oranga, Whakapapa, Wairua, and Taonga Tuku Iho (see Table 2 and Fig. 3).
Table 2 - Māori core values and principles for soil health
|Māori core values and principles|
|Mana||Authority and rights to manage land, soil, and resources. To exercise mana and kaitiakitanga over resources. Recognition of the Treaty of Waitangi – Māori land versus tribal interests from local to national rights and interests.|
|Mauri||Life force or energy, vitality and continuing capacity of the soil to sustain/support life, health, and well-being. Strong connection between soils and people.|
|Mahinga kai||Ability of the soil to provide sustenance, food sovereignty and prosperity.|
|Oranga ora||Ability of the soil to provide and ensure health and well-being in accordance with tikanga and kawa e.g. no human waste or contaminants.|
|Whakapapa||Ancestral links between people and place. Kaitiakitanga is practised over nature resources/whenua.|
|Wairua||The spiritual dimension/domain important to local people – helps to maintain or strengthen mana and mauri to achieve a well-balanced, functioning soil ecosystem.|
|Taonga Tuku Iho||Soil health is maintained in areas for future generations. Wise land use options to sustain the soil.|
These principles are now being used to form a framework in which we can develop and identify Māori soil health indicators that could potentially be used alongside science-based indicators. Some of our findings are encapsulated in the following interview extract from Kiri Reihana’s 2017 interview with Hema Wihongi:
Whakapapa defines what a healthy soil is, it comes from our whakapapa, we define ourselves from our pepeha, our land. So whatever happens to the soil happens to me, when we are disenfranchised from our soil, our land, it also affects our physical and mental health...The indicators and measures of soil health can be seen in the place names, the geographical whakapapa.
Much of this information on Māori soil health is being documented in a book on Māori perspectives of soil health, Oneone ora Tangata Ora: A Māori soil Sovereignty handbook, edited by Jessica Hutchings and Jo Smith, to be published in 2020.
To understand what is driving New Zealand’s soil management and policy, a workshop was held in Wellington in May 2019, with representatives from regional and central Government, science organisations, and the agricultural sector. Participants identified a wide range of soil issues, including land use changes and fragmentation, the suitability of soil types, urban development, climate change, soil loss through erosion, a reduction in soil carbon and biomass, compaction and contamination, soil being undervalued, cultural changes, complex farming systems & farming profitability, and surveillance and monitoring of soil. This workshop reiterated the need to address the breadth of these issues in a more integrated and holistic way to include Te Ao Māori concepts, and both land and water policies. There was a sense that a value shift in soil is needed because soil matters and is integral to our well-being. Workshop participants saw a strong need for a Soil Health Champion, a National Soil Management Group, and clear, action-based terminology to link standardised public policy outcomes with soil security. A poster of this workshop can be found on the Soil Health Policy Workshop webpage.
We are also connected to several international programmes that involve soil health. The Soil Health Institute in the United States is testing a number of new indicators. including biological indicators across a wide range of climates, land uses, and soils to determine which are most useful. The concept of Soil Security is also emerging from Australia as a framework for sustainable and regenerative land-use management by tying together soil capability, condition, capital, connectivity and codification. This approach fits well with both Treasury well-being indicators and New Zealand’s commitment to reporting on UN Sustainable Development Goals.