Research has shown that New Zealanders would need at least two Earth planets to sustain our current lifestyles compared with a ‘fair Earth share’ of one. Some estimates put this number as high as five Earths.
Two papers released today by the Royal Society of New Zealand explore how many people, and to what standard of living, can New Zealand support sustainably. The papers argue that sustainability is not a simple trade off between the economy and the environment.
The papers explore a number of areas where the issue of sustainability is a factor and that might constrain our ability to create ever-more well-being: climate change, food production, water quality, native biodiversity, transport and fisheries.
The Society’s Chief Executive, Dr Di McCarthy, says the papers offer a framework for looking at how New Zealand generates well-being for New Zealanders and our trading partners, and presents strategies for how to operate within the constraints in our resources. The framework allows New Zealanders to consider the risks to well-being faced due to our dependence upon these finite resources.
“The use of our land, water and other resources, and our levels of well being and prosperity are not simple tradeoffs between the economy and the environment. Instead, the relationships are complex and interwoven.”
When managing a river, for example, there is not a simple trade off between the economy and the environment through taking the water out for irrigation and leaving it in for recreational users.
Different user groups will value the water differently. Raft companies may wish to see a year-round consistent flow to continue their tourism operations; recreational kayakers may value peak flows for challenging paddles; anglers may wish to see minimum flows maintained to ensure fish survival; iwi and environmental groups may want annual flushing to remove algae to ensure river health; farmers may want flow available in spring and summer for irrigating pastures. Sustainable management of the river will take into account the viewpoints of all user groups.
Dr Suzie Greenhalgh, Portfolio Leader of Governance and Policy for Landcare Research, and speaker at the launch of the paper at the Royal Society of New Zealand said: “Our responses to constraints in our natural resources must recognise that there are many connections between the economy and the environment.
“Each connection has its own characteristics, leading to its own tool-kit of responses to ensure continued or even increasing benefits. Setting environmental limits and trading within those limits is only one approach. Other approaches include optimising for co-production of benefits, managing resources with the aim of maximising total value produced, and optimising management for many different values.”
“For freshwater, increases in pastoral agriculture have resulted in a seven-fold increase in the use of nitrogenous fertiliser over the past twenty years, and the volume of water allocated for irrigation has reached or exceeded current limits in many areas. Both of these are affecting our freshwater lakes, rivers and streams.”
New Zealand currently produces enough calories for 20 million people and enough protein for 45 million people. The overall well-being that New Zealand can generate using the finite resources available to us depends upon how we manage and use those resources. For example, shifting dairying off leaching-prone land and onto more suitable land can reduce overall nitrogen pollution without reducing overall output and farm profitability. A study to model land use north of Lake Taupo found that nitrate leaching could be reduced by 8% and soil erosion by 14% with no change to farm income and food, wool and wood production by moving dairying off leaching-prone land.
Despite options for better performance, our progress towards better use of those resources is, in many cases, slow. While New Zealand’s economy has grown by 68% over the past twenty years, our greenhouse gas emissions have only increased by 20%, so some progress is being made in decoupling economic growth from emissions. However, this progress is not rapid enough yet to halt the growth of our overall greenhouse gas emissions, despite our extensive potential supplies of renewable energy.
