Environment New Zealand 2007 questions and answers: Key findings - Land
Environment New Zealand 2007 publications
What are the key findings on land in the report?
In a nutshell
- Agriculture remains our largest human land use.
- While the total area in pasture has decreased slightly in recent years, the area in dairy pasture and the national dairy herd have both increased. This intensification of land use has led to increases in fertiliser use, water use and greenhouse gas emissions.
- Urban areas have increased slightly in recent years.
- Horticultural land area has largely stayed the same, but there has been diversification of horticultural crops.
- The area in exotic forest cover has increased, although rates of new planting are the lowest in many decades, and replanting rates have tailed off.
- Soils under cropped (horticultural) land and agricultural land are generally in poorer condition than under other land uses, with higher levels of compaction, build up of nitrogen and phosphates, and lower levels of organic carbon.
- During the 1990s, hill country erosion eased in some regions, as some pasture on erosion-prone land was planted into forestry or left to revert to scrub.
Facts and figures
- Agricultural land use has intensified. The total area of New Zealand land in pasture has decreased since 1972 (it is now just under 40 per cent of New Zealand’s total land area), however land in dairy pasture has increased. In addition, today’s national dairy herd has grown by 24 per cent since 1996.
- Between 1997 and 2002, pastoral land cover decreased by just over 1 per cent (or 125,200 hectares); human settlements increased by about 2.5 per cent (or 5,500 hectares); and exotic forest cover increased by about 8 per cent (or 139,500 hectares).
- Horticultural land use has diversified: for example, the area of land in vineyards grew by 28 per cent between 1997 and 2007.
- In addition, new ‘niche’ crops such as olives, wasabi and saffron are being commercially grown.
- Since 1998, the rate of new exotic forest plantings has declined to the lowest level since 1959.
- In 2004, a new trend of not replanting exotic forestry after harvesting became apparent.
- Soil monitoring results show widespread moderate compaction of soils under pastures and horticultural land.
- Soil compaction is caused by farm animals treading on pastures, and vehicle traffic and cultivation on croplands.
- Nitrogen and potentially mineralisable nitrogen were highest under pastures than any other land uses.
- Average levels of nitrogen in dairy soils were 70 per cent higher than in soils under native forests and 125 per cent higher than in soils under tussock grasslands.
- Dairy pasture levels of potentially mineralisable nitrogen were 60 per cent higher than native forests and 72 per cent higher than tussock grasslands.
- Phosphate levels were also high under some dairy farming soils.
- About 10 per cent of New Zealand is classed as severely erodible.
- Between 1997 and 2002, there was a 36,400-hectare reduction in pasture on erosion-prone hill country at the national level. 36,300 hectares were converted to exotic forestry or retired and left to revert to scrub.
What is the government doing to improve the quality and management of New Zealand’s land and soil?
A number of initiatives which are relevant to land are underway and under development. Examples include: