10 Apr 2024

More productive land being used for urban development, study finds

10:50 am on 10 April 2024

Study funds jump in amount of productive land being used for urban development and increase in amount of highly erodible land.

A view of the lower Wanganui River in South Westland showing the line of silt and debris left from where the river broke breached a stop bank and flowed across farmland towards Lake Ianthe, in the distance. Much of that farmland is reclaimed riverbed.

Five percent of the country's soil is highly erodible, the majority of that in the North Island. Photo: Supplied / West Coast Regional Council

More productive soil is eroding away or being used for urban development a new snapshot of land use has found.

The Ministry for the Environment and Stats NZ has [https://mcusercontent.com/ebebf9501bcd56a598aa9f357/files/1840ea79-6e45-3dc2-d0b0-e2cf189e2e34/EMBARGO_Our_land_2024_snapshot.pdf

just published the latest three yearly update] about the state of land around the country.

It shows 5 percent of the country's soil was classified as highly erodible in 2022 - of that 60 percent was in the North Island.

And despite soil being a finite resource, approximately 182 million tonnes eroded into our rivers in the same year.

"Our activities on land have compromised both the quality and quantity of our soils through deforestation, urban sprawl and intensification, and agricultural intensification.

"Climate change is adding to these pressures, exacerbating flooding, landslides and erosion," the report said.

It pointed out how vital soil was for New Zealand's agricultural and horticultural economy which was worth $55.3 billion in the year to June 2023.

"For many Māori soil is also of great cultural significance, fundamental to māra kai and viewed as a living entity with deep connections to whakapapa, ancestral lineage."

The report said there was a 54 percent increase in highly productive land being used for urban or residential purposes between 2022 and 2019.

The snapshot pointed out that reducing the land available for horticulture could have consequences for food prices.

"The reduced availability of highly productive land in the Auckland and Waikato District could contribute, alongside other factors, to an increase in fruit and vegetable prices of up to 58 percent across the

country by 2043."

Ministry for the Environment deputy secretary Natasha Lewis said ecosystems, such as soil, indigenous forests, wetlands, flood plains, and dunes were the foundation natural assets and infrastructure that underpinned our economy.

"Soil is crucially important because it is the foundation for other natural infrastructure. It also plays a vital

role in our economy, soil is a strategic asset.

"A lot of our GDP is in the top 15cm of the ground we walk on," she said.

Lewis said the ways we use land were placing our natural infrastructure under pressure.

"Accounting for the full range of benefits that nature provides will help us to develop enduring solutions for the way we manage land," she said.

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