The 1997 report, The State of New Zealand’s Environment 1997, concluded that:
The main pressures on soil are from past deforestation of erodible land, localised accumulations of harmful chemicals or waste products, and the impacts of over-cultivation or overstocking on erosion-prone and compaction-prone land. …
Soil conservation is increasingly the land users’ responsibility. Forest planting, regeneration of native vegetation on some erosion-prone land, and the formation of landcare groups are the main response trend.
(Ministry for the Environment, 1997, chapter 10.)
As in 1997, New Zealanders today continue to rely heavily on the land for their economic, social, and cultural well-being.
The main pressures on New Zealand’s land today continue to be driven by the predominant land uses of agriculture, horticulture, and forestry.
Today, pastoral agriculture remains New Zealand’s main land use.
While the total area of New Zealand land in pasture has been decreasing since 1972, the area of land in dairy pasture has increased (Ministry of Agriculture and Forestry, pers comm).
Between 1997 and 2002, satellite measurements of the area of pasture (high-producing exotic grassland and low-producing grassland) show that:
in 1997, pasture covered almost 40 per cent of New Zealand’s total land area
in 2002, pasture covered just over 39 per cent – a decrease of 125,200 hectares (or almost 1 per cent).
As the extent of pastoral land shrank, its productivity grew. Economic drivers in our primary sector have seen a significant intensification of pastoral land use in New Zealand, particularly over the last decade. The average farm size has grown by 19 per cent since 1997, as has greater use of off-farm inputs, such as irrigation water and fertiliser (Organisation for Economic Co-operation and Development, 2007).
The shift to more intensive pastoral land use has placed greater pressures on the health of some soils, in turn affecting water quality. For example, dairy cows excrete almost seven times the amount of nitrogen and phosphorus in their faeces and urine as breeding ewes. Moderately compacted soils, nitrogen build-up, and high levels of available phosphate under some dairy pastures means the condition of pasture soils continues to have a major bearing on water quality nationally. In addition, with irrigation (primarily for agriculture) now using 80 per cent of all allocated water in New Zealand, intensification of land use has had a significant impact on water availability in some regions.
Changes in livestock numbers between 1996 and 2006 also reflect the recent trend towards intensification of land use.
Sheep numbers decreased from 47 million to 40 million (from a peak of 70 million in 1983).
Beef cattle numbers decreased from 4.8 million to just under 4.5 million.
Dairy cows numbers increased from just over 4 million to just over 5.2 million.
Deer numbers increased from 1.1 million to just over 1.5 million.
In 2006, numbers of livestock equated to 9.93 sheep, 2.39 cattle (1.29 dairy cattle and 1.09 beef cattle), and 0.39 deer for every person in New Zealand.
The increases in some herd sizes have also increased our total greenhouse gas emissions from agriculture. This is particularly so for larger-sized animals, which produce more greenhouse gases than smaller-sized animals.
The intensification of dairy and deer farming has been particularly notable in Canterbury and Southland.
Since 1997, while land in horticultural use is estimated to have remained relatively steady at just under 1.6 per cent of our total land area, horticultural land use in New Zealand has shown significant diversification. As an example, between 1997 and 2002, vineyards increased in area by 5,500 hectares (28 per cent). As the horticultural sector has diversified, export earnings have increased from $115 million in 1980 to $2.5 billion in 2006.
In addition, new emerging ‘niche’ crops are now being commercially grown. For example, olives, a number of new grape varieties, wasabi, hazelnuts, saffron, and truffles are all now commercially grown in New Zealand, despite little historical tradition of these crops. The area of land used for organic farming more than tripled over the same period (Organisation for Economic Co-operation and Development, 2007).
In part, diversification in the horticultural sector reflects changing land use in other sectors. For example, the arable cropping sector has increased its focus on producing maize silage for the dairy sector.
The expansion in recent years of urban growth and rural lifestyle subdivision is putting increasing pressure on soils of high value for mixed cropping and vegetable production (‘versatile soils’).
In 2006, exotic forestry covered 1.8 million hectares of New Zealand land. However, since 2004, replanting rates have declined. New planting rates have dropped from 60,000 hectares in 1997 to 5,000 hectares in 2006 (the lowest since 1959). An increasing proportion of exotic forests are not being replanted after harvesting with some of that land now being converted into pasture. If this trend continues, New Zealand’s total land area in commercially planted exotic forest will continue to decline from its post-1990 peak in 2003.
The reduction in exotic forest cover has implications for the sequestration of carbon dioxide (a greenhouse gas), and may affect hill-country erosion, and flood management. Agriculture on converted forestry land may also produce higher nutrient run-off and affect water quality.
However, farm forestry has remained popular over the last decade as farmers moved to further diversify their farms and benefit from other values that farm forestry provides. This includes planting for soil conservation on erosion-prone hill country.
Changing soil health
Today, as in 1997, our soils underpin food and fibre production in New Zealand. Seventeen per cent of New Zealand’s gross domestic product now depends on the top 15 centimetres of our soil. This percentage is likely to increase as primary land use continues to diversify and intensify (for example, more new niche crops or more intensive farms).
Over the last decade, soil monitoring shows there have been changes to the health of soils under New Zealand’s predominant land uses. Monitoring results show:
widespread moderate compaction under pastures and some cropping land uses
a loss of organic matter and soil structural stability under cropping
nitrogen build-up under some dairy pastures, coupled with high levels of available phosphate (Sparling, 2007).
Most declines in soil health are potentially reversible, but the shift to more intensive farming practices in many regions may make a reversal difficult to achieve for some soils.
Sustainable land management
A notable change since 1997 is growing awareness, both domestically and internationally, of the environmental impacts of land use, including for food production.
In response, a wide range of groups have implemented initiatives for sustainable land management and primary production. A number of key sector groups have also adopted formal environmental management systems.
Soil conservation programmes
Since 1997, land owners and users have increasingly taken responsibility for soil conservation, including soil health, and soil erosion. Voluntary and government-subsidised soil conservation programmes, including the East Coast Forestry Project, have achieved localised reduction in soil erosion on hill-country farmlands over the past 10 or more years. Budget 2007 announced a commitment of $10 million for the next four years to continue this work and to manage hill-country erosion under the Sustainable Land Management Framework and Fund.
The Sustainable Management Fund (established in 1996) and Sustainable Farming Fund (established in 2002) continue to support land-care groups and farming-related projects. Over 45 projects have been funded since 1997 and just over $8.5 million has been made available specifically for sustainable land management projects to address:
flood prevention and management
poor soil health.
New national-level monitoring information about freshwater quality has helped target soil conservation and sustainable land-management efforts in catchments where water quality has been degraded. This information has aided the development of integrated catchment management programmes. The need for better regional soil mapping information has also been highlighted as a critical information need for effective sustainable land management planning.
Regional council programmes
Regional councils around the country continue to work with land-care groups and farmers to encourage best environmental management practices on rural land in their regions. This work has included:
programmes that promote revegetation of river and stream banks to enhance water quality, which also benefits soil conservation and biodiversity
the National Land Monitoring Forum completing a soil quality monitoring protocol and beginning a soil erosion monitoring protocol
involvement in the 2005–2006 Envirolink initiative, which supports regional council research into environmental management and sustainability, for example, to fill knowledge gaps about the soils in their regions and assist better decision-making about sustainable land use.
Environmental management systems and codes of practice
Since 1997, increasing numbers of farm, horticulture, and forest operators have adopted environmental management systems (EMS) and codes of practice, for example:
Sustainable Winegrowing New Zealand (490 members in 2006)
Forest Stewardship Council standards (covering 42 per cent of New Zealand’s commercial plantation forests)
Market Focused (a dairy farmers’ EMS initiative in 2001)
Official Organic Assurance (as of 2003, 800 farms were either certified organic or converting to organic status) (Organisation for Economic Co-operation and Development, 2007).
Dairying and Clean Streams Accord
In 2003, the Dairying and Clean Streams Accord was agreed between Fonterra Cooperative Group (which represents over 95 per cent of New Zealand’s dairy farm milk producers), regional councils, and the Government.
The Accord includes five targets aimed to achieve clean healthy water in streams, rivers, lakes, groundwater, and wetlands in dairying areas. Progress against the Accord targets is measured by the results of an independently audited On-farm Environmental and Animal Welfare Assessment. Results for 2005/2006 show progress towards the Accord’s five targets has been steady, although not all targets have been met.
New Zealand Forest Owners’ Association code of practice
In August 2007, the New Zealand Forest Owners’ Association released its new Environmental Code of Practice for Plantation Forestry.
This new code is a practical guide to forest operations throughout the life cycle of a forest crop. The code helps forest owners identify and manage the environmental values that plantation forestry provides:
stable water flows
carbon storage and oxygen exchange
recreational areas for people to enjoy.
(New Zealand Forest Owners’ Association, 2007).
Funding for agri-environmental research
Between 1997 and 2004, public science funding for agri-environmental research in the agricultural and forestry sectors grew from $136 million to $193 million (Organisation for Economic Co-operation and Development, 2007).
Contamination of localised sites around the country as a result of past horticultural, forestry, and agricultural practices has left New Zealand with a suite of ‘legacy’ land-use pressures on the environment.
Since 1997, local government has continued to work to identify contaminated sites and ensure contaminated land is appropriately managed. A total of 4,424 sites have now been screened across the country. To date, 559 high-risk sites have been identified. Of these, 56 per cent have already been cleaned up or have a clean-up or management programme in place.
Several tools have been developed in the last decade to accelerate and improve the identification, management, and remediation of contaminated sites in New Zealand. They include government and industry-based guidelines, funds to assist local government investigate and clean-up sites, and tax deductions for business related clean-up costs.
In 2005, the Resource Management Act 1991 was amended to include a definition of contaminated land.
Pests and diseases brought into New Zealand have the potential to seriously damage natural resources and to threaten our land-based economy. Some successes have been achieved in eradicating unwanted pests, such as the white-spotted tussock moth. However, new invasive species such as the varroa bee mite, didymo, and the clover root weevil have become established since 1997 (Organisation for Economic Co-operation and Development, 2007, Ministry of Agriculture and Forestry, pers comm.).
With the flow of goods and people into New Zealand increasing every year, biosecurity is now as much about preventing unwanted pests and diseases from arriving in New Zealand as it is about controlling or eradicating them once they are here.
This widening focus for biosecurity led to the formation of Biosecurity New Zealand in 2004. Biosecurity New Zealand, a division of the Ministry of Agriculture and Forestry, has the lead role in:
preventing unwanted pests and diseases from reaching New Zealand
controlling, managing, or eradicating them should they arrive.
In the future, the focus on land management in New Zealand is likely to intensify on how to:
continue to minimise the impacts of intensified land use on our soils and waterways
identify and manage land contaminated by historical agricultural and industrial activities
continue to manage hill-country erosion
continue to manage biosecurity risks to New Zealand’s primary production sector and native species
meet growing consumer demand for sustainably produced agricultural, horticultural, and forestry products.