"Our Land" on International Earth Day
As the world marks International Earth Day, the “ Our Land 2021 ” report by Statistics New Zealand and the Ministry for the Environment is still being digested here.
The report was released late last week and is the latest in a series of environmental reports looking at air, marine, freshwater, and climate issues here in Aotearoa.
Key takeaways from the report highlight the loss of productive food growing land to urban sprawl, an eroded environment under pressure from more cows and increased intensification.
The Our Land 2021 report was compiled by Statistics NZ and the Ministry for the Environment.
Our land 2021 explores the impact of New Zealand’s growing population, export-driven economic growth, and the demand for housing in the future.
The report authors say while urban land cover continues to make up one percent of total land area in New Zealand they can see urban and residential development is moving onto productive land, which creates tension between the use of land for housing and land for agriculture.
“This results in a complex trade-off, as using land that is not highly productive for food growing results in lower yields unless more intensive land management approaches are used. Intensive land management brings with it the risks of degrading the quality and health of the soil and the wider environment.”
Secretary for the Environment Vicky Robertson says the report shows how the health of our land impacts on the health of our rivers, lakes, oceans, air, indigenous biodiversity, climate - and our own wellbeing.
“Land is central to our identity as people of Aotearoa New Zealand. It is our tūrangawaewae, our place to stand.
“The choices we make for where we build, what we grow for ourselves, and what we export are creating tensions for the best use of available land. Climate change and a growing population are only going to make future choices more difficult.” she says.
“For Our land 2021, we have made great strides in bringing together data from a range of other agencies, and adding value through our analysis, interpretation and presentation,” Government Statistician Mark Sowden says.
“In particular, we have developed new and updated indicators that provide invaluable information on changes to New Zealand’s land and soil.”
Key facts from the report are;
The number of consumers in New Zealand is projected to reach 6.8 million by 2073 having passed 5 million in June 2020. This will continue to drive the demand on land to supply food, housing, and opportunities for recreation.
About half of the total land area in New Zealand is used for agriculture, forestry, and housing: land cover exotic grassland 40%, exotic forestry 8%, cropping & horticulture 2%, urban 1%, native land cover 49%. (Note: These percentages exclude lakes and rivers.)
87 percent of the population live in towns and cities. About 80 percent of our population growth for 2018–43 is expected to be in the main urban centres.
15 percent of land is particularly good for food production. This highly productive land has a good climate, suitable soil, and is flat or gently sloping. Here, less irrigation and fertiliser is needed to grow food than in other areas. Highly productive land is often on the fringes of our cities.
Highly productive land became more fragmented between 2002 and 2019, especially through residential development of land sized 2–8 hectares (lifestyle blocks are about 5 hectares on average). The area of highly productive land that was unavailable for agriculture (because it had a house on it) increased by 54 percent during this period, from 69,920 hectares in 2002 to 107, 444 hectares in 2019.
The total area of land used for agriculture and horticulture has been decreasing since 2002 with an overall reduction of 1,878,409 hectares (14%) between 2002 and 2019, and a reduction of 207,747 hectares (2%) between 2017 and 2019, and the number and size of farms has decreased during the same period, with a reduction of 19,980 farms (29%) and 2,028,710 hectares (13%) between 2002 and 2019. However, the export income from farming products has increased, from $23 billion in 2010 to $44 billion in 2019 (primary industries export revenue excluding seafood)
Dairy cattle numbers have more than doubled since the 1980s, rising from 3 million to almost 7 million in 2015, with more than 6 million in 2019.
The use of irrigation, especially on land used for dairy farming, has nearly doubled since 2002. In 2019, 5 percent (735,073 hectares) of agricultural land in New Zealand was irrigated, with dairy farming making up 58 percent of irrigated agricultural land 2019.
The sale of phosphorus fertiliser peaked in 2005 at 219,000 tonnes per year. It has reduced since then, with 154,000 tonnes sold in 2019. The sale of nitrogen fertiliser increased sharply from 62,000 to 452,000 tonnes per year between 1991 and 2019.
Nationwide, 80 percent of monitoring sites failed to meet the targets for at least one soil quality indicator. No declining or improving trend in soil quality was observed for 1994–2018.
Macroporosity - a measure of pore spaces in soil and a potential indicator of soil compaction - was below the target range in 65 percent of dairy farming sites, 48 percent of drystock farming sites and 46 percent of orchard/vineyard sites sampled between 2014 and 2018. No decreasing trend or improvement in macroporosity was found in drystock farming or in dairy farming from 1995 to 2018.
Levels of Olsen phosphorus, an indication of soil fertility, were above the recommended target range for 61 percent of the dairy farming and cropping sites, and 46 percent of orchard/vineyard sites sampled between 2014 and 2018. High levels of Olsen phosphorus in the soil indicate that too much fertiliser has been applied.
A range of events are being held around the world to mark earthday.org