Economy v Environment: Is fewer cows really the answer?

There's plenty of evidence that more farm production could actually help, not harm, efforts to protect the environment

New Zealand's future depends on production and protection - but the latter is not necessarily the same as preservation. These 'P-words' are getting as muddled as the 'E-words' of expertise, experience and enthusiasm.

Economics and environment are also part of that picture.

In discussing water quality, Parliamentary Commissioner for the Environment Dr Jan Wright has described New Zealand’s current predicament as a ‘classic economy versus environment dilemma. And because ‘discussion of farming’s effects on water quality is becoming too politicised’, Fish and Game New Zealand has called for an independent review of the direction of agriculture in New Zealand.

Rebecca Macfie’s article in The Listener (May 31st) covers the issues extremely well. On the Canterbury Plains the economy is booming because of dairy conversions and efficient use of water. This money is helping, with the Christchurch rebuild, to make the Canterbury region one of the most vibrant economically in the country.

The Ministry of Business, Innovation and Employment released the 2014 Regional Economic Activity Report last week. The Canterbury region is the largest in New Zealand, and contributes 13.4% of national GDP, 13.4% of national employment and is home to 12.7% of population. The report states that:

"There are a range of opportunities to sustain the growing economy. The dairy farming sector could still increase productivity, particularly through sustainable water management, adapting new technologies and expanding into new markets. There is also opportunity for more added-value processing of rural products."

While the dominance of the primary sector in the export economy is known, the importance in Gross Domestic Product is often overlooked. Agriculture, Forestry and Fishing has 6% of employment and 7.2% of GDP (in the MBIE report). Dairy farming alone has 1.5% of employment and contributes 3.2% of GDP. In some contrast, Horticulture (including viticulture) has 1.3% of employment and 0.6% of GDP.

In the Manufacturing sector, Food and beverage has 3.1% of employment and 4.2% of GDP.

The primary sector is vital.

And the primary sector acknowledges that it has had an impact on waterways. The dairying industry, for instance, is aware of its impacts and working towards mitigating them. DairyNZ spends 28% of its income levied from farmers (currently forecast to be $61 million for the 2013/14 season) on on research and development to increase farm profit and productivity. Other significant expenditure is to consulting officers and demonstration farms (12%) and training, education and leadership (10%).

This means approximately $25 million is spent on research, development and extension.

Independent evaluation of DairyNZ’s investment portfolio by NimmoBell rates "research on farming with environmental limits" as the most valuable project, returning $96/ha/yr for the average farm.

In Canterbury, concerns are focussed on increased nitrate loading in rivers, and confusion continues about the implications of nitrate in water.

Concerns about human health are not supported by a detailed review commissioned by the World Health Organisation. Dr Lorna Fewtrell’s review, entitled Drinking-Water Nitrate, Methemoglobinemia, and Global Burden of Disease: A Discussion and published in Environmental Health Perspectives in October 2004, concluded that:

  • No exposure–response relationship could be identified that related drinking-water nitrate level to methaemoglobinaemia.
  • It is currently inappropriate to attempt to link illness rates with drinking-water nitrate levels.

Environmental toxicity is, however, a different issue. Nitrate does affect the ability of freshwater organisms to grow and reproduce. This season "dairy farmers are getting praise from unlikely quarters after the largest number of salmon in 40 years have been seen spawning in a stream in the middle of dairying country". Fish & Game New Zealand has been reported to attribute the main reason for high salmon numbers to the work of dairy farmers in fencing, planting and protecting the stream, all of which take money.

Further south, record salmon catches are being made, as they were last year. Last year the whitebait season was not good, explained by the wet autumn (which could have washed away eggs during spawning) but the previous year was reported as ‘bumper’.

Increasing nutrient availability often supports increased biomass at various levels in the food chain. However, increased nutrient loading can create stress.

The recent Ruataniwha Dam ruling put a limit of 0.8mg/litre dissolved inorganic nitrogen (nitrate and ammonia) on water for the future. Immediately there have been statements from the productive sector of what this constraint will mean. NIWA has shown (in a map commissioned by IrrigationNZ) that many areas of New Zealand are already above this limit, meaning that further productivity, however much indicated as possible by the government, would not be permitted by the Environment Court.

Prime Minister John Key has been reported to say that nitrate levels set by the board of inquiry for the Ruataniwha Water Storage Scheme could undermine future schemes, and also to indicate that a legal challenge was likely.

Exactly what grounds the challenge will be made upon isn’t yet clear, but 0.8 has already been described as "devastating for farming".

It isn’t emotion, however, that should rule the day, devastating or not. Facts, evidence, data and logic are the way forward. Science must be involved and results interpreted dispassionately. And then the classic economics versus environment debate can occur.

A review of international literature and toxicological databases of nitrate toxicity to freshwater aquatic species was prepared for Environment Canterbury by NIWA researchers in 2009. The limitations of the review included that "a total of 20 species were used for the acute deviation, and only four of these are found in Canterbury’s water bodies". One was the Chinook salmon. The authors warned that the datasets used were ‘particularly lacking in species which are known to be of high sensitivities’ and ‘no information is available on the sensitivity of native fish species to nitrate’.

NIWA suggested guideline values of 1.0 mg N as nitrate/litre for high conservation systems – pristine environments with high biodiversity and conservation limits.

This value was for nitrate alone, whereas the 0.8 value in the Ruataniwha ruling was for nitrate and ammonia.

The NIWA researchers suggested for environments which are subjected to a range of disturbances from human activity, 1.7 mg nitrate per litre would give 95% protection.

For specific environments which received seasonally high elevated backgrounds for significant period s of the year, 2.4-3.6 mg N as nitrate /litre was given as the guideline value.

In the Thames, nitrate is reported by the OECD to be 7 mg N as nitrate/litre, the fish are back, and fishing has become a sport again.

Add to this confusion the challenge of what might actually happen with intensification and the modellers will start explaining the limitations and constraints of their models – and the significant uncertainties in any modelling exercise.

Using technologies such as barns, loafing areas, feed pads at certain times of the day and year, nitrate leaching from dairy cows can be reduced – even halved as suggested by research at Massey University.

Feeding supplements such as maize or palm kernel expeller also reduces the amount of N in the urine, allowing more to go into higher production of milk.

When farmers have a profitable business, they can invest – and fence and plant waterways as well. Increasing productivity from their land, which might mean changing type of stock (from beef, sheep or deer to dairy, for instance), or might mean increasing stock numbers, often makes business sense. Land that is suitable for dairying but is currently under beef and sheep has been estimated to bring in at least four times as much if converted. Water storage, and irrigation, is key.

Analysis in 2010 by NZIER estimated the economic impact of 14 irrigation schemes predominantly in the Canterbury, Hawkes Bay and Wairarapa regions would be an increase in GDP of 0.8%, and value of exports of $4 billion.

Land-use change would generate a net revenue gain of approximately $6,000 per hectare in Canterbury and $1,300 per hectare in Hawkes Bay at the farm-gate.

With economic growth driven by the regions, more can be invested in research and development to support the environment - to protect the 32% of New Zealand that is already in the conservation estate, and enable farmers to implement new technologies to reduce the impact of producing food.

Calls for a return to fewer cows and all grass-farming as in the 1980s overlooks the fact that water quality then was considerably worse than it is now. Considerable improvements have been made in stopping city effluent getting into rivers, enabled by economic growth, taxes and rates.

Facts, evidence and data make the logic clear: production enables protection.