New report highlights importance of natural assets and infrastructure

• Our land 2024 full report
• Our land 2024 snapshot

Our land 2024 brings together recently updated Stats NZ indicator data, as well as insights from research literature.

The report shows how the ways we use land have wide-ranging effects on our diverse ecosystems and the biodiversity they support, with impacts on our economies, homes, resilience to disasters, cultural identity and public health.

The Ministry’s Deputy Secretary – Strategy, Stewardship and Performance, Natasha Lewis, says ecosystems, such as soil, indigenous forests, wetlands, flood plains and dunes, are foundational natural infrastructure that underpins our economy, helps to protect us against disasters and supports public health.

Services this infrastructure provides include supporting our food sector, reducing soil erosion, draining catchments and protecting coastal areas against storm surges and sea level rise. “We appreciate the benefits that built infrastructure provides, but many of us don’t think of, or value, natural ecosystems and landscapes in the same way,” she says.

Soil is crucially important because it is the foundation for other natural infrastructure. It also plays a vital role in our economy.

In the year ended June 2023, Aotearoa New Zealand’s food and fibre sector accounted for $55.3 billion in export revenues, which represented more than 75% of the nation’s export goods. “Soil is a strategic asset. A lot of our GDP is in the top 15 cm of the ground we walk on,” she says.

But degrading or developing over our natural infrastructure increases the food and fibre sector’s susceptibility to soil erosion, pests, diseases and the effects of climate change and extreme weather. Treasury has estimated that damage to the sector from Cyclone Gabrielle and the 2023 Auckland floods may total between $700 million to $1.1 billion in recovery costs.

A recently updated Stats NZ indicator in the report shows that 5 percent of our land is classified as highly erodible land and at risk of mass-movement erosion. “Topsoil is a finite resource, but 182 million tonnes of eroded soil entered our waterways in 2022,” she says.

Other threats to the primary food sector include loss of fertile land to urban expansion. Deloitte estimated in 2018 that fruit and vegetable prices could rise by up to 58 percent across the country by 2043 if fertile land at Pukekohe was developed. “This is important contextual information for decision-makers who decide where development can occur,” she says.

Other examples of natural infrastructure include urban green spaces which soak up stormwater, improve air quality and provide recreational areas that support our wellbeing.

In some major cities, the availability of public green spaces, such as parks and town belts, is not keeping pace with urban expansion.

Private green space is also declining, because of a shift towards denser infill housing and smaller sections. About 30 percent of Auckland’s urban area consists of private green space. Expected population growth and intensification could potentially reduce this area by 5–10 percent (3,000 hectares) over the next two decades.

“The ways we use land are 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 says.

The report brings together recently updated Stats NZ indicator data and insights from research literature to highlight pressures on land in Aotearoa New Zealand. These can cause, or contribute to, changes in the state of the environment, which have various impacts. Key insights from the report include:

Updated ‘Highly erodible land’ indicator

Highlights from the updated indicator:

• 5 percent (12,693 km²) of New Zealand’s 267,338 km² of land was classified as highly erodible land at risk of mass-movement erosion in 2022.
• 60 percent of the area at risk of mass-movement erosion was in the North Island, despite the North Island comprising only 43 percent of the total land area of New Zealand.
• Risk of erosion by landslide was the most common class of erosion risk, representing 75 percent (9,575 km²) of areas at risk of erosion, or 4 percent of New Zealand’s total land area.
• Manawatū-Whanganui had the largest area of highly erodible land at risk of mass-movement erosion; 2,208 km² or 17 percent of total highly erodible land in New Zealand.
• Of all regions, Gisborne had the highest proportion of its area classified as highly erodible land at risk of mass-movement erosion (15 percent, 1,280 km²).
• Many areas across New Zealand had significantly higher proportions of highly erodible land at risk of mass-movement than the country on average.  

Updated ‘Estimated long-term soil erosion’ indicator

Highlights from the updated indicator:

• In 2022, an estimated 182 million tonnes of eroded soil entered Aotearoa New Zealand’s rivers. Of all regions, the West Coast (48 million tonnes) and Gisborne (36 million tonnes) had the highest levels of sediment movement into waterways. 
• Between 2016 and 2022, hot spots were identified in Northland, the east coast of the North Island, Taranaki, Waikato, and the West Coast regions, representing statistically significant clusters of locations with high rates of soil erosion compared to the national average. 

Pressures on our land

• It is highly likely that urban densification will increase pressure on urban green spaces, while urban expansion will continue to put pressure on highly productive land (moderate confidence).
• Agricultural expansion and intensification put pressure on soil health, water quality and indigenous biodiversity.
• It is highly likely that the area of exotic forest plantation will increase by 2030, with a growing proportion being managed for carbon sequestration (moderate confidence).
• Development on and near floodplains in coastal areas exposes many communities and infrastructure to flooding risk. It is almost certain that pressures on flooding protection measures and coastal dune systems will increase under climate change (high confidence).
• It is almost certain that climate change will put increasing pressures on the ecosystems and biodiversity that underpin the functioning of our natural infrastructure (high confidence).
• It is highly likely that pressures from pests and diseases will increase, threatening our biodiversity and putting our vulnerable ecosystems at risk (moderate confidence).
• Waste and contaminants from activities on land, including landfills, industry and agriculture, are polluting our soil and water.

State of our land

• Soil quality is not always within target ranges on land that supports our primary industries.
• The availability of highly productive land has decreased. Should present trends persist, it is highly likely that the availability of highly productive land will continue to decrease (moderate confidence).
• The area of exotic land cover has expanded, mostly with conversion from exotic grassland to exotic forest.
• Indigenous forest, scrub and tussock is particularly vulnerable in lowland areas, with some ecosystems fragmented and in poor condition.
• Natural erosion varies across Aotearoa New Zealand, though erosion rates have accelerated due to deforestation, grazing animals, and intensive land use. Climate change is likely to spur an increase in mass-movement erosion in some areas, particularly in soft-rock hill country (moderate confidence).
• Floodplains and braided rivers are important habitats but have lost area to urban and rural development.
• Wetlands and dunes are among our most depleted ecosystems and continue to be lost.
• It is highly likely the quantity and quality of urban green space will continue to decline in some cities over the next two decades (high confidence).
• Many indigenous species are at risk.

Impacts 

• The reduced availability of highly productive land can challenge types of food production.
• Damage to our natural infrastructure can incur high costs and cause significant economic losses. Land-based industries will almost certainly experience increased economic risks due to degrading natural infrastructure (high confidence).
• It is highly likely that the degrading state of our natural infrastructure will reduce the regulating and flood protection services provided to surrounding communities and built infrastructure (high confidence).
• The health of our natural infrastructure affects the wider environment, including the climate, and freshwater and coastal ecosystems.
• Our physical health reflects the health of the environment that we spend time in. For example, urban areas produce and absorb more heat than outlying areas. Urban heat can exacerbate air pollution and worsen certain health conditions, particularly for older people.
• As urban green space declines and demand for it increases, it is likely that these changes will alter our connection to urban green space and, consequently, the recreational and mental health benefits it provides (moderate confidence).
• Loss and degradation of te taiao results in a loss of Māori knowledge, practices and culture.

Waikato University's Science Learning Hub has produced learning resources about land for teachers and students to complement the official report.  

• Our land 2024
• Land-use decisions and extreme weather
• Restoring Te Auaunga – Oakley Creek
• Environmental monitoring – ao Māori perspectives

For further information and requests for comments about the report, contact the Ministry for the Environment media team:

• 027 231 6930 
• media@mfe.govt.nz

For technical information about the environment indicators, contact the Stats NZ media team: 

• 021 285 9191
• media@stats.govt.nz