Federated Farmers conference �30^th June 2011

Dr Russel Norman

Green Party

Land use revolution 1990-2010

• Dairying more extensive
• Dairying more intensive
• Environmental impacts

Synthetic fertilizer use in New Zealand

NZ Fertilizer use

Global Fertilizer use

433 Gg in 2007

Prof David Hamilton

Figure from Paul White (GNS)

1990

2005

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Consented groundwater abstractions,

Canterbury region

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Dairy farms in Southland

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1992

2006

Nitrogen leaching

Prof David Hamilton

In a finite planet more extensive and intensive dairying has downstream environmental impacts

Redfin bully

Impact on Water Quality

Water Quality Trends

• SOURCE
• Water quality trends at National River Water Quality Network sites for 1989–2007
• Deborah J. Ballantine, Robert J. Davies-Colley
• NIWA

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Water Quality Trends

• ^{“There were strong increasing trends in four nutrients (total phosphorus, dissolved reactive phosphorus, oxidised nitrogen and total nitrogen).”}
• ^{“There are strong correlations between these trends and the percentage of catchment in pasture, which indicates deteriorating water quality is mainly attributable to expansion and intensification of pastoral agriculture.”}
• Water quality trends at National River Water Quality Network sites for 1989–2007, Deborah J. Ballantine, Robert J. Davies-Colley, NIWA

Water Quality Trends

^{“Overall, some aspects of water quality have deteriorated in rivers over the past 20 years mainly as a result of farming (pastoral land cover)}

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^{and environmental gains in terms of reduced ‘point’ pollution of waters in New Zealand are being overshadowed by increasing diffuse’ pollution.”}

• Water quality trends at National River Water Quality Network sites for 1989–2007, Deborah J. Ballantine, Robert J. Davies-Colley, NIWA

Impact on periphyton (nuisance algal growth)

Periphyton Growth

• “Mean filamentous periphyton cover was also strongly positively correlated with percentage pastoral land cover in the catchment”
• “More sites with decreasing cover than increasing cover. This encouraging finding was not expected given the increasing agricultural intensification and associated increase in nutrient inputs and instream concentrations over this period.
• Some of the trends of declining cover may be associated with improvements in point source effluent management (e.g., Mataura and Manawatu Rivers), but it appears that other factors may also be influencing periphyton cover at NRWQN sites.

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• ^{Trends in nuisance periphyton cover at New Zealand National River Water Quality Network sites 1990-2006 John M. Quinn, Ernst Raaphorst - NIWA}

Impact on Biodiversity

Biodiversity Impacts

• SOURCE
• “Conservation Status of NZ Freshwater Fish 2009”
• Richard Allibone, Bruno David, Rodney Hitchmough, Donald Jellyman, Nicholas Ling, Peter Ravenscroft & Jonathan Waters,
• New Zealand Journal of Marine and Freshwater Research Dec 2010

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Conservation Status of NZ Freshwater Fish 2009

• Two thirds of native fish are threatened or at risk.
• Dairy conversions were "leading to increased water demand, increasing habitat modification and potential declines in water quality”
• Richard Allibone, Bruno David, Rodney Hitchmough, Donald Jellyman, Nicholas Ling, Peter Ravenscroft & Jonathan Waters, New Zealand Journal of Marine and Freshwater Research Dec 2010

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Biodiversity Impacts

• SOURCE
• “Temporal and land-cover trends in freshwater fish communities in New Zealand’s rivers: an analysis of data from the New Zealand Freshwater Fish Database – 1970 – 2007” Prepared for the Ministry for the Environment March 2009
• Mike Joy Massey Uni

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Biodiversity

“Temporal and land-cover trends in freshwater fish communities in New Zealand’s rivers: an analysis of data from the New Zealand Freshwater Fish Database – 1970 – 2007” Prepared for the Ministry for the Environment March 2009 Mike Joy Massey Uni

Koaro

Giant bully

Impact on Lakes

NIWA – Lake Water Quality in NZ 2010

• "The most significant finding from this study … is that pastoral land use ..is associated with …ecological deterioration.”
• “The condition of some lakes currently in good condition is declining, likely as a result of nutrient enrichment from livestock farming.“�

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• SOURCE
• “Relationships between land use and nitrogen and phosphorus in New Zealand lakes”
• Jonathan M. Abell, Deniz Ozkundakci, David P. Hamilton and Steven D. Miller
• Marine and Freshwater Research, 2011, 62, 162–175

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Land Use and N and P in lakes

Land Use and N and P in lakes

• “high producing grassland (intensive pasture) was the best predictor of TN and TP”
• “Mitigating eutrophication in New Zealand lakes requires action to reduce nutrient export from intensive pasture”
• “Relationships between land use and nitrogen and phosphorus in New Zealand lakes”, Jonathan M. Abell, Deniz Ozkundakci, David P. Hamilton and Steven D. Miller, Marine and Freshwater Research, 2011, 62, 162–175

Abell, Ozkundakci and Hamilton (2010): Ecosystems

A comparison with N and P in lakes internationally

Is it all about P, not N?

• SOURCE
• “Nitrogen and Phosphorus Limitation of Phytoplankton Growth in New Zealand Lakes: Implications for Eutrophication Control”
• Jonathan M. Abell, Deniz Ozkundakci, and David P. Hamilton
• Ecosystems 13(7): 966-97

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Is it all about P not N?

• “We examine macronutrient limitation in NZ lakes.
• “A review of published results of nutrient enrichment experiments showed that N more frequently limited lake productivity than P
• “Dual control of N and P should be the status quo for lacustrine eutrophication control in New Zealand and more effort is needed to reduce P inputs.
• “Nitrogen and Phosphorus Limitation of Phytoplankton Growth in New Zealand Lakes: Implications for Eutrophication Control”, Jonathan M. Abell, Deniz Ozkundakci, and David P. Hamilton, Ecosystems 13(7): 966-97

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NIWA – “What the science really says”

• NRWQN – National River Water Quality Network
• “The overall picture emerging from the NRWQN is that our water quality, while generally good by international standards, is declining”.
• “Trends in NRWQN data between 1989 and 2007 show an overall degradation in water quality in our major rivers”

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NIWA – “What the science really says”

• Nitrogen increased by about 1.4% per annum over most of the country, but remained steady at pristine sites like Haast River”
• “Trends for phosphorous were mostly up”
• “Upward trend for temperature, nitrogen and phosphorous have strengthened in recent years compared with 1989-2003”

Trends in Nitrogen

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National River Water Quality Network

NIWA 2010

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NIWA – “What the science really says”

• “The NRWQN monitoring… show that diffuse pollution from land use is overwhelmingly the main cause of water quality degradation in NZ today”
• “Pastoral farming… is undoubtedly the main source of diffuse pollution”

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NIWA – “What the science really says”

• “Between 1992 and 2002 the number of cows in the Waikato increased by 37%; during the same period the nitrogen levels in the region’s streams increased by 40% and phosphorous levels went up by 25%”

NIWA – “What the science really says”

• “There is no doubt that our declining river water quality over the last 20 years is associated with the intensification of pastoral farming and the conversion of drystock farming to dairy farming particularly in Waikato, Southland and Canterbury”

Trout

• Do have a significant impact on native fish
• But like native fish are intolerant of poor water quality
• Cannot be primary reason for increase in algae and degraded water quality since 1990
• The increase in algae has occurred against a backdrop of static or declining trout numbers

Trout – AD Huryn 1998

• The comparative study of ecosystem characteristics of the streams used in the present study, however, does not provide a definitive statement regarding the effect of the introduction of trout on New Zealand streams.
• Although the ecosystem-level characteristics of Sutton Stream and Stony Creek support predictions about differences in trophic dynamics between streams with trout or native fish based on experimental studies (Flecker and Townsend 1994; McIntosh and Townsend 1996), firm conclusions are obscured by fundamental differences between the streams.
• Alexander D. Huryn, Ecosystem-level evidencef or top-down and bottom-up control of production in a grasslands stream system, Oecologia (1998) 115:173 183

Landcare Research Annual Report

• “Agricultural intensification over the past 10 years has led to the highest rate of native vegetation loss since European colonisation.”
• Landcare Research Annual Report 2009

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Giant

Kokopu

Attacking the scientists

• “We have jaundiced freshwater ecologists blaming land based industries”
• “It's much easier to blame farmers if you happen to be running a separate agenda.”
• “Bad science is not science, but opinion dressed in impressive clothing.”
• Lachlan Mackenzie, Fed Farmers

Conclusions

• Are freshwater scientists conspiring to attack farmers?
• No, they are doing their job
• Is there good science behind the claim that intensive agriculture leads to water pollution and ecological decline
• Yes, it is overwhelming and well understood
• Does it help farmers if the Feds attack the scientists?
• No, it is embarrassing and is leaving farmers isolated

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20 year land use revolution

• Money, jobs, profits, exports
• Nitrogen use and leaching increase massively
• Biodiversity collapse in pastoral catchments
• Dangerous groundwater pollution
• Faecal contamination of waterways
• Rapid native bush clearance
• Public backlash

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We must reduce the environmental footprint of dairying

Must reduce intensity

Business case for lower intensity

• Profits roughly similar
• Maybe lower output overall
• Save money on inputs
• Protect, enhance ‘clean green and safe’ brand
• Maintain and enhance market access to
• higher value markets concerned with enviro & safety
• lower value markets concerned with food safety

• “Case study has indicated potential to reduce nitrogen leaching considerably to low levels (26 kg N/ha/yr) with varying impacts on profitability
• “In some cases, low leaching systems are more profitable than the base line.
• Upper Waikato Nutrient Efficiency Study 2009

Bluegill bully

• High value markets increased sensitivity to environmental issues
• Especially on carbon, welfare and water eg Waitrose, Tescos labelling

Dairy Exports

Why? Melamine. NZ is clean green safe

Lake Taihu, China

• Need strong environmental regulation
• To set standardised environmental bottom lines
• To create a level playing field
• For long term benefit of dairy

Land Price effects

• Global resources grab
• Uncertain impact on NZ so far
• But heading our way

“We’re seeing a change in the ownership structure of larger scale farms, and while the family farm is still very significant in that, we’re seeing a major increase in the private companies which are often called equity partnerships.”

FarmRight Chief Exec

One of the major changes in New Zealand dairy farming has been … in the transition from traditional owner-operator dairy farmers to syndicate farm ownership and other structures such as limited liability companies.

Dairy NZ

• Challenging the loss of the family farm
• Capital adequacy ratios
• Counter cyclical capital adequacy ratios
• Stop foreign ownership
• Capital gains tax excluding family home

Mat Allan