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Carbon footprinting of New Zealand lamb from the perspective of an exporting nation

Carbon footprinting of New Zealand lamb from the perspective of an exporting nation Carbon footprinting of New Zealand lamb from the perspective of an exporting nation Stewart F. Ledgard,* Mark Lieffering,† Dan Coup,‡ and Ben O’Brien§ *AgResearch Ruakura Research Centre, Private Bag 3123, Hamilton 3240, New Zealand; †AgResearch Grasslands Research Centre, Palmerston North 4442, New Zealand; ‡Meat Industry Association, PO Box 345, Wellington 6140, New Zealand; and §Beef + Lamb New Zealand, PO Box 121, Wellington 6140, New Zealand most Chinese production is consumed domestically, whereas NZ exports about 92% of its total lamb production. Internationally, sheep production is Implications diverse and sheep are multi-purpose animals producing meat, milk, skins,  Contributors to the carbon footprint of New Zealand lamb ex- and wool, although meat production is their primary function (Zygoyiannis, ported to the United Kingdom across the life cycle were the 2006). Sheep are commonly grazed on native or introduced forages and are cradle-to-farm-gate (80%; mainly animal-related emissions), able to forage and survive in many areas where cattle perform poorly. processing (3%), retail/consumption/waste (12%), and ship- In NZ, sheep are typically farmed with beef cattle and sometimes with ping (a small component at 5%). deer on long-term perennial grasslands. These farms are predominantly  Sheep farming uses low inputs and all-year grazing of pe- located on hill or high country, and pressure from other greater profi tability rennial grasslands. Nevertheless, large effi ciency gains have farming systems, such as dairying, means that sheep numbers are decreasing occurred with a 22% smaller on-farm carbon footprint com- and they are increasingly being confi ned to more extensive steeper grassland pared with 1990 from increased lambing percentage and lamb areas. Poor economic returns from lamb and sheep coproducts over the past growth rates. decade have resulted in emphasis on the remaining farms to increase lamb  In the wider sustainability context of food production, sheep productivity and effi ciency to remain viable. have a low environmental impact and utilize grassland on hills Sheep farming systems in the temperate climate of NZ are based on all- and steepland that have limited other uses. year grazing of permanent perennial grass and white clover pastures, no use of brought-in feeds, and low inputs. Fertilizer nitrogen (N) use on NZ sheep −1 −1 and beef farms averages approximately less than 10 kg of N·ha ·year , and much of this is used for winter feed for cattle (B+LNZ, 2010). A key Key words: coproduct, grassland, life cycle assessment, reduction feature of farm management is the use of grazing practices that maintain high-quality pastures, particularly for fi nishing lambs at high growth rates. Introduction The average lambing from ewes is approximately 125%, and most lambs Sheep meat constitutes a relatively small proportion of the meats are fi nished to a fi nal live weight of 40 kg within 5 to 9 months. Lambing consumed globally (approximately 6%), and in developed countries it is a in early spring means that the pasture growth pattern matches feed demand niche product. New Zealand (NZ) is the world’s largest exporter of lamb and most lambs are processed in summer/autumn. After processing, most at more than 40% of total global exports (FAO, 2008). NZ lamb meat is shipped to the northern hemisphere in their winter/spring Lamb from NZ is exported widely and the main markets are in northern period, supplying the market during a period of low local lamb supply. hemisphere countries, with the largest single market being the United Kingdom (UK). This means a long transportation distance to markets with Why Undertake a Lamb Carbon associated costs and implications for “food miles” and related greenhouse Footprint Study? gas (GHG) emissions. This paper reports on a research study on the carbon footprint (i.e., Consumer awareness about carbon footprinting of products is high in total GHG emissions throughout the life cycle of a product) of NZ lamb certain markets, and this has been led by supermarkets, particularly in the exported and consumed in the UK. It also considers the wider implications UK. This has resulted in a demand for information on the carbon footprint and context for meat production and GHG emissions reduction. of products supplied to some major supermarket chains or to intermediate businesses that supply them. For NZ exporters, interest in footprinting has International and NZ Lamb Production been accentuated by NZ’s long distance from many markets and possible concern about the related transport GHG emissions. China is the world’s largest producer of sheep meat at nearly 2 Mt, Within NZ, the government has also initiated an emissions trading followed by Australia at 0.8 Mt and NZ at 0.6 Mt (FAO, 2008). However, scheme, which has put a charge on GHG emissions from fossil fuel and electricity use. In addition, animal-related emissions from agriculture © 2011 Ledgard, Lieffering, Coup, and O’Brien. doi:10.2527/af.2011-0010 are scheduled to be phased into the scheme (MfE, 2011). These market 40 Animal Frontiers Downloaded from https://academic.oup.com/af/article-abstract/1/1/40/4638598 by Ed 'DeepDyve' Gillespie user on 10 April 2018 and domestic policy drivers have resulted in the need for producers and containers, chillers/freezers, and retail and household refrigerated exporters to be aware of their contribution to the carbon footprint of cabinets) (Ledgard et al., 2009a). products and of footprint reduction opportunities. Primary data on energy use, consumables, refrigerant leakage, wastes, and effl uent processing were collected from lamb processing plants from throughout NZ (covering more than 40% of total lambs processed). Data Carbon Footprint Methodology on typical shipping distance to the UK (20,750 km) were combined with a An attributional life cycle assessment (LCA) approach (e.g., conservatively high emission factor for refrigerated container shipping of Thomassen et al., 2008) was used to estimate the carbon footprint of 0.05 kg of CO -equivalents (CO eq.)/tkm (including fugitive emissions 2 2 NZ lamb exported by ship to the UK, cooked, and consumed by a UK of refrigerants) to estimate shipping GHG emissions. Secondary data were household and including waste (uneaten lamb and sewage) stages (Figure used in estimating GHG emissions from retail (Carlsson-Kanyama and 1). The functional unit was 1 kg of processed NZ lamb meat purchased Faist, 2000), household (including cooking; Foster et al., 2006), and waste by a UK consumer. stages. Emissions associated with the production of capital items, transport Emphasis was on the whole life cycle and applying methods that of consumers to and from the point of retail purchase, and changes in soil complied with ISO14044 (BSI, 2006) and PAS2050 (BSI, 2008), carbon were all excluded (according to PAS2050; BSI, 2008). particularly since the UK is a major market for NZ lamb. To conform to PAS2050, customer travel was excluded but sensitivity analysis was used Main Findings and Life Cycle Implications to examine effects of its inclusion. Survey data from Beef + Lamb NZ (B+LNZ, 2010) covering more The carbon footprint averaged 19 kg of CO eq./kg of lamb meat, with than 400 sheep and beef farms throughout NZ was used to calculate GHG 80% from the cradle-to-farm-gate (mainly animal methane and nitrous emissions from different farm classes and to determine an NZ weighted oxide emissions), 3% from processing, 5% from all transportation stages average. Animal production data were used in an energy-based (tier 2) (predominantly from shipping), and 12% from retailer/consumer/waste model (Clark et al., 2003) to estimate dry matter intake for the sheep stages (dominated by retail storage and home cooking; Figure 2; Ledgard et breeding and lamb production system. Biophysical allocation (e.g., Flysjö al., 2009a, 2010). Thus, all stages throughout the life cycle contribute to GHG et al., 2011) was used to allocate GHG emissions between animal types, emissions and can contribute to reduction of the carbon footprint. Sensitivity and economic allocation (5-year average) was used to allocate between analysis was used to examine effects of alternative practices at all stages of the lamb, mutton, and wool production from sheep. New Zealand-specifi c life cycle. At the consumer stage, inclusion of consumer transport to purchase emission factors for methane (enteric and fecal), and nitrous oxide from the meat added up to 7% to the total carbon footprint depending on the mode excreta and leached N were used based on the NZ GHG Inventory (MfE, of transport and food purchasing practices. The method of cooking by the 2007). Other emissions accounted for included embodied CO emissions consumer was also important with cooking-related emissions being 20% from electricity and fuel use, CO from fertilizer production and urea greater by roasting the lamb compared with frying it. and lime application to soil, and refrigerant emissions (from refrigerated At an NZ lamb processor level, emissions were most dependent on energy source, energy use effi ciency, and effl uent processing system. For Figure 1. Simplifi ed system diagram showing the main life cycle stages, inputs, outputs, fl ows, and coproducts. July 2011, Vol. 1, No. 1 41 Downloaded from https://academic.oup.com/af/article-abstract/1/1/40/4638598 by Ed 'DeepDyve' Gillespie user on 10 April 2018 Figure 2. Relative contribution from the main life cycle stages to the carbon footprint of New Zealand (NZ) lamb consumed in the United Kingdom (UK; Ledgard et al., 2010). example, moving from an anaerobic waste water system to an aerobic Thus, the largest opportunity to reduce GHG emissions on-farm is to increase one could potentially decrease processing GHG emissions by up to 30%. the effi ciency of feed conversion into lamb meat. This has been occurring In practice, improvements at most NZ lamb processing plants have been steadily over time as evident from the reduction in methane emissions per made over time by shifting from anaerobic pond processing of effl uent kilogram of sheep meat produced in NZ (Figure 3). The main reasons for (with associated methane emissions) to land application and using the this are an increase in the lambing percentage of ewes (from about 100% in waste as a nutrient source for grass growth. Similarly, processors have early 1990s to 125% in 2008), increased growth rate of lambs, and fi nishing increased energy use effi ciency and moved away from burning coal to the lambs at heavier weights (Morris, 2009). Thus, in 2009, NZ sheep farms use of gas or other energy sources. One processor (Silver Fern Farms, NZ) produced slightly more lamb meat by weight compared with 1990, but from has recently switched to the use of a Bubbling Fluidised Bed boiler, which a 43% smaller national fl ock (B+LNZ, 2010). This has been estimated to is able to utilize sludge from waste water treatment and woodchips as fuel coincide with a reduction in GHG emissions from cradle-to-farm-gate by sources instead of coal, which had been used. approximately 22% (Ledgard et al., 2010). Ongoing improvement in the NZ Technological changes can affect the supply chain and the carbon sheep sector is also occurring through an increase in the proportion of ewe footprint. For example, lamb has traditionally been frozen and shipped to hoggets mated (again resulting in more lamb production for each kilogram the UK, but in the past decade there has been a large increase in vacuum- of feed eaten by the breeding fl ock). In practice, the main driver of these packed chilled lamb providing increased quality and shelf-life of up to 14 reductions in GHG emissions is the need for increased farm profi tability weeks. Sensitivity analysis indicated that the chilled lamb supply chain through increased on-farm effi ciency. used less energy compared with the freeze chain, but it only decreased the Sensitivity analyses indicated limited ability to reduce the carbon total carbon footprint by approximately 0.7%. footprint by targeting other sources of on-farm GHG emissions. One In the transportation stages, shipping was the main contributor to total possibility examined was to cease use of N fertilizer on farm because transport-related emissions. However, it was also identifi ed as being very it has high manufacturing-related emissions (e.g., Ledgard et al., 2011). effi cient, with emissions per ton per km (excluding refrigeration) at about However, bearing in mind the current very low N fertilizer use on NZ 0.01 kg of CO eq. compared with about 0.08 for trucking and 0.3 for farms and the reduced productivity from ceasing its use, the effect was a household car (based on various modeled analyses). In this study, a calculated to be a reduction in carbon footprint of <1%. Nevertheless, conservatively large emission factor was used for shipping refrigerated where N fertilizer use is signifi cant, the integration of clovers in pastures containers of 0.05 kg of CO eq. per ton per kilometer (including backhaul that can fi x atmospheric N and replace N fertilizer has the potential 2 2 of an empty container), whereas others have used values of less than one- to greatly reduce fossil fuel use and decrease the carbon footprint. For half of this (e.g., 0.018 by Williams et al., 2008). Thus, the food-miles example, Ledgard et al. (2009b) estimated a 12% reduction in carbon −1 −1 associated with transportation of product to market were only a minor footprint for an NZ dairy system receiving 160 kg of N·ha ·year by contributor to the total carbon footprint. substituting fi xed-N for fertilizer-N. Farm GHG Emissions and Reduction How Does the Carbon Footprint of NZ Lamb Opportunities Compare with That from Other Studies? There have been few other studies that have examined the carbon The cradle-to-farm-gate stage was the main contributor to the carbon footprint of lamb, and they have all stopped at the farm-gate or the retail footprint, and this was predominantly from animal-related methane and distribution center. For the carbon footprint from the cradle-to-farm-gate, nitrous oxide emissions (comprising 72% of the total carbon footprint). 42 Animal Frontiers Downloaded from https://academic.oup.com/af/article-abstract/1/1/40/4638598 by Ed 'DeepDyve' Gillespie user on 10 April 2018 2-fold. Paradoxically, the least emissions were from Merino sheep produced on high country, even though they had the least effi ciency of productivity (i.e., least lambing percentage, lamb growth rates, and fi nishing body weights). This was simply an artefact of economic allocation being used, with greater allocation of total sheep emissions to wool (and therefore less to meat) for Merinos due to their much greater monetary returns per kilogram of wool compared with that for the strong wool (used for carpets) produced by other NZ sheep breeds. The magnitude of a carbon footprint will depend on the range of coproducts produced and their value or signifi cance or both. Lamb produces a range of coproducts including meat, wool, hide (used for making leather), blood, offal (some components representing delicacies for certain cultures, such as stomach lining or tripe), tallow (with a range of uses including for Figure 3. Calculated methane emissions from New Zealand average sheep meat biofuels), and renderable components that are processed into products, such based on B+LNZ (2010) data and use of the New Zealand greenhouse gas inventory as animal feeds. If the latter 4 coproducts were worthless and went to waste methodology (MfE, 2007). (e.g., to landfi ll or to the effl uent system, as had happened to a varying extent in the past), then a greater component of total lamb GHG emissions estimates for various studies in kilograms of CO eq. per kilogram of lamb would be allocated to meat. Whereas the use of economic allocation may body weight were 12.9 or 51.6 for 2 Welsh case study farms (Edwards- accentuate these differences, other allocation methods such as system Jones et al., 2009; the high value was due mainly to specifi c peat soil expansion will also be infl uenced by coproducts with other uses and value. N O emissions), 10 for an average Irish farm system (Casey and Holden, However, meat is the most valuable product from lamb and currently the 2005), and 8.6 in the current study. Williams et al. (2008) estimated GHG nonmeat coproducts may constitute about 50% or more of the body weight emissions to a UK retail distribution center for lambs produced in the UK but usually provide less than 20% of total economic returns. or NZ at 14.1 and 11.6 kg of CO eq./kg of lamb product, respectively. However, it must be noted that there were differences in methodology across How Does the Carbon Footprint of Lamb all of these studies, particularly for methane estimation method (e.g., tier 1 Compare with That of Beef or Other Meats? versus tier 2 methods; IPCC, 2006), different Intergovernmental Panel on Climate Change (IPCC) emissions factors, different system boundaries, Generic studies comparing meat types have generally shown much and different allocation methods. This means that the values outlined smaller carbon footprint values (by about 5- to 10-fold) for white meats above cannot be directly compared, although Williams et al. (2008) from nonruminants (pigs, poultry) than for red meat from ruminant applied the same methodology in comparing lamb from 2 countries. The animals (e.g., Dalgaard et al., 2007; Williams et al., 2008). A key factor in strong impact of methodology highlights the need for research papers to this difference is the enteric methane emissions from forage digestion by report all methods and data used so that others might recalculate a carbon ruminant animals. footprint for comparative purposes. There are many more published studies on the carbon footprint of More importantly, the variability between studies in the methods used beef than of lamb. For the cradle to-farm-gate stage, most beef studies emphasizes the desirability of defi ning and agreeing on a methodology are within the range of 7 to 19 kg of CO eq./kg of body weight, with such as through product category rules (BSI, 2008). This is particularly results infl uenced greatly by methodological differences as well as by important in methodology aspects for products where there is a strong farm system differences. The study of Williams et al. (2008) included infl uence on the fi nal carbon footprint value (e.g., for allocation between evaluation of the carbon footprint for UK beef and lamb based on coproducts). The International Dairy Federation recently released a generic models that accounted for the range of farm systems that exist. common methodology for dairy carbon footprinting through a common Their estimate for GHG emissions per kilogram of body weight for process involving international dairy companies and LCA researchers, the cradle-to-farm-gate stage for average UK lamb was only 57% of and this represents an ideal process. The International Meat Secretariat has that for the average UK beef. Similarly, our recent carbon footprint supported the same approach to be developed for a common methodology studies also showed smaller carbon footprint values for average NZ for lamb carbon footprinting, and this is currently underway. lamb than for NZ beef (average for traditional suckler breeding and bull beef systems), at 8.6 and 10.5 kg of CO eq./kg of body weight, What Factors Influence Variability respectively (Ledgard et al., 2010; M. Lieffering, S. Ledgard, M. Boyes, and R. Kemp, AgResearch, New Zealand, unpublished). This smaller Between Studies? carbon footprint for lamb can be attributed to greater fecundity in sheep As well as differences in methodology between studies, the carbon (e.g., 125% lambing by ewes compared with 95% calving by breeding footprint of lamb can vary with the farm system used and between cows), greater average growth rates in lambs, and wool as a coproduct individual farms. Similarly, there will be variation between different from sheep. However, it must also be recognized that in most countries processors’ contribution to the footprint (e.g., by about 2-fold per kilogram a signifi cant component of the beef is derived from cull dairy cows, of lamb processed in the current study) and at other stages, including in which have a small carbon footprint, and in NZ its inclusion brings the retail and consumer practices. weighted average carbon footprint for beef at the farm-gate down to the The few individual case farms and farm types examined in the current same value as that for lamb. This further highlights the importance of study showed variation in cradle-to-farm-gate GHG emissions of about July 2011, Vol. 1, No. 1 43 Downloaded from https://academic.oup.com/af/article-abstract/1/1/40/4638598 by Ed 'DeepDyve' Gillespie user on 10 April 2018 (Schipper et al., 2010), and similar conclusions were drawn from French accounting for whole production systems and coproducts when carrying research in temperate grasslands (Sousanna et al., 2004). More research out a carbon footprint analysis. is needed to better understand processes affecting this and the temporal The carbon footprint values outlined above all refer to averages for pattern of carbon accumulation so that it can be appropriately accounted different systems or countries. In practice, there is a large variation between for in carbon footprinting. Additionally, large losses of CO occur from individual farms within a farm system or country, and this variation is cultivation during crop production due to oxidation of soil carbon, likely to overlap the apparent differences between the published averages. whereas the carbon in grassland soils is important for carbon retention. Although some of this variation between farms is due to inherent site factors and therefore is unmanageable, much of it can be attributed to differences in farm management practices and provides opportunities for improvement. Concluding Comments Low environmental impacts, including a low carbon footprint, A Carbon Footprint Is Just One should be one goal in our quest for effi cient food production systems Environmental Indicator from our global landscapes. Sheep farming systems are important because they utilize diffi cult grassland landscapes with limited other Whereas lamb and other red meats have a greater carbon footprint than uses and the lamb produced from it is a valuable niche source of red white meats, there are context issues and other environmental indicators meat globally. From an exporting nation’s perspective, NZ provides that should be considered in assessing the wider sustainability of food a complementary out-of-season supply of quality lamb to northern products. Pigs and poultry are generally fed on grains from crops on hemisphere countries with effi ciency goals including a low total carbon land that could alternatively be used for crops for direct consumption footprint. From a global perspective of limiting GHG emissions, there by humans. In contrast, ruminants can utilize feed sources that cannot is a desire for low carbon footprint food systems irrespective of the be utilized by nonruminants, and in the case of sheep this is largely source of supply, provided other acceptable standards of food quality, grassland that is on land unsuitable for cropping. For example, in the UK environment, and welfare are met. This places pressure on exporters the latter includes upland and hill areas, whereas in NZ it also includes to be able to supply product into overseas markets with a low total steep hill country and high-altitude tussock country. This land is generally carbon footprint and consequently on achieving ongoing reductions in unsuitable for other food production purposes. the carbon footprint of their products. Life cycle assessment is widely used in determining the carbon The study of the carbon footprint of NZ lamb covered all the “cradle- footprint of products, but it is also a useful tool for examining resource use to-grave” stages, and more whole life cycle studies are required for other effi ciency and other environmental indicators. Food production based on animal and food options. The lamb study showed that GHG emissions low energy use, and particularly low fossil fuel use, is desirable to ensure are dominated by utilization of grassland by sheep at the farm stage. supplies of fossil fuels are available for other more critical requirements. However, it also showed that there have been large gains in effi ciency, Lamb production from long-term grasslands typically has low fossil fuel with a reduction in the carbon footprint over time at the farm level of over use compared with that from intensive agriculture such as dairy farming. 20% since 1990. Other contributors, including consumers, to the carbon For example, in the NZ lamb study the average fossil fuel use was 26 MJ/ footprint of the lamb life cycle can also reduce the footprint through kg of protein produced to the farm-gate stage in comparison with about improved technological, management, and behavioral practices. 210 MJ/kg of protein for milk produced in the Netherlands (Thomassen et al., 2008). Acknowledgments Lamb production on grasslands also has a low impact on water quality. In NZ the average N concentrations in waterways measured in sheep- The authors thank James McDevitt (Scion, Wellington, New −1 −1 dominant catchments equated to an N loss of 3 kg of N·ha ·year , which Zealand) and Mark Boyes (AgResearch, Hamilton, New Zealand) was less than that in catchments dominated by other livestock types, but for their contribution to life cycle assessment modeling; Robert Kemp −1 −1 greater than the 2 kg of N·ha ·year from forest catchments (McDowell for data collection; the New Zealand meat processing companies and and Wilcock, 2008). The average for NZ dairy catchments was about 27 Beef+LambNZ (Wellington, New Zealand) for data; and Ministry of −1 −1 kg of N·ha ·year , and NZ studies with cereal crops have shown similar Agriculture and Forestry (Wellington, New Zealand), Meat Industry N leaching rates to that for dairying. Although there was less difference Association (Wellington, New Zealand), Landcorp (Wellington, New across catchments and livestock types in phosphorus loss to waterways, Zealand), and Ballance Agri-nutrients (Mount Maunganui, New Zealand) sheep catchments again had the least losses (other than forests). for project support. Another feature of landscapes grazed by sheep is the relatively high biodiversity. In NZ, most sheep farms have signifi cant areas of Literature Cited native or planted trees, particularly on steeper and erosion-prone areas. B+LNZ. 2010. Compendium of New Zealand Farm Facts. 34th ed. April 2010. Although offsetting of GHG emissions is not included in carbon footprint Beef + Lamb New Zealand Publication No. P10013. analyses, at an individual farm and national GHG inventory level the BSI. 2006. EN ISO 14044:2006. International Standard. Environmental recently forested areas represent signifi cant carbon sinks. 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Holistic analysis of GHG emissions from Irish livestock production systems. Paper No. 54036. Am. Soc. Agric. Biol. About the Authors Eng., Tampa, FL, USA. Stewart Ledgard is a principal scientist with Clark, H., I. Brookes, and A. S. Walcroft. 2003. Enteric Methane Emissions AgResearch and an adjunct professor of the from New Zealand Ruminants 1990–2001 Calculated Using an IPCC Tier 2 Life Cycle Management Centre at Massey Approach. Report for the NZ Ministry of Agriculture and Forestry, Wellington, University in New Zealand. His research New Zealand. focus is the management of resource use and Dalgaard, R., N. Halberg, and J. E. Hermansen. 2007. Danish pork production: environmental impacts of pastoral farming An environmental assessment. DJF Animal Science, 82. University of Aarhus, systems. During the past decade, this has Denmark. 38p. involved application of life cycle assessment Edwards-Jones, G., K. Plassmann, and I. M. Harris. 2009. 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He is life cycle assessment of food commodities procured for UK consumption a member of the International Meat Secretariat’s Sustainable Meat Committee through a diversity of supply chains. DEFRA Project FO0103. and has an interest in promoting a single international greenhouse gas life cycle Zygoyiannis, D. 2006. Sheep production in the world and in Greece. Small Rumin. analysis methodology for lamb.  Res. 62:143–147. July 2011, Vol. 1, No. 1 45 Downloaded from https://academic.oup.com/af/article-abstract/1/1/40/4638598 by Ed 'DeepDyve' Gillespie user on 10 April 2018 http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png Animal Frontiers Oxford University Press

Carbon footprinting of New Zealand lamb from the perspective of an exporting nation

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© 2011 Ledgard, Lieffering, Coup, and O'Brien
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2160-6056
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2160-6064
DOI
10.2527/af.2011-0010
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Abstract

Carbon footprinting of New Zealand lamb from the perspective of an exporting nation Stewart F. Ledgard,* Mark Lieffering,† Dan Coup,‡ and Ben O’Brien§ *AgResearch Ruakura Research Centre, Private Bag 3123, Hamilton 3240, New Zealand; †AgResearch Grasslands Research Centre, Palmerston North 4442, New Zealand; ‡Meat Industry Association, PO Box 345, Wellington 6140, New Zealand; and §Beef + Lamb New Zealand, PO Box 121, Wellington 6140, New Zealand most Chinese production is consumed domestically, whereas NZ exports about 92% of its total lamb production. Internationally, sheep production is Implications diverse and sheep are multi-purpose animals producing meat, milk, skins,  Contributors to the carbon footprint of New Zealand lamb ex- and wool, although meat production is their primary function (Zygoyiannis, ported to the United Kingdom across the life cycle were the 2006). Sheep are commonly grazed on native or introduced forages and are cradle-to-farm-gate (80%; mainly animal-related emissions), able to forage and survive in many areas where cattle perform poorly. processing (3%), retail/consumption/waste (12%), and ship- In NZ, sheep are typically farmed with beef cattle and sometimes with ping (a small component at 5%). deer on long-term perennial grasslands. These farms are predominantly  Sheep farming uses low inputs and all-year grazing of pe- located on hill or high country, and pressure from other greater profi tability rennial grasslands. Nevertheless, large effi ciency gains have farming systems, such as dairying, means that sheep numbers are decreasing occurred with a 22% smaller on-farm carbon footprint com- and they are increasingly being confi ned to more extensive steeper grassland pared with 1990 from increased lambing percentage and lamb areas. Poor economic returns from lamb and sheep coproducts over the past growth rates. decade have resulted in emphasis on the remaining farms to increase lamb  In the wider sustainability context of food production, sheep productivity and effi ciency to remain viable. have a low environmental impact and utilize grassland on hills Sheep farming systems in the temperate climate of NZ are based on all- and steepland that have limited other uses. year grazing of permanent perennial grass and white clover pastures, no use of brought-in feeds, and low inputs. Fertilizer nitrogen (N) use on NZ sheep −1 −1 and beef farms averages approximately less than 10 kg of N·ha ·year , and much of this is used for winter feed for cattle (B+LNZ, 2010). A key Key words: coproduct, grassland, life cycle assessment, reduction feature of farm management is the use of grazing practices that maintain high-quality pastures, particularly for fi nishing lambs at high growth rates. Introduction The average lambing from ewes is approximately 125%, and most lambs Sheep meat constitutes a relatively small proportion of the meats are fi nished to a fi nal live weight of 40 kg within 5 to 9 months. Lambing consumed globally (approximately 6%), and in developed countries it is a in early spring means that the pasture growth pattern matches feed demand niche product. New Zealand (NZ) is the world’s largest exporter of lamb and most lambs are processed in summer/autumn. After processing, most at more than 40% of total global exports (FAO, 2008). NZ lamb meat is shipped to the northern hemisphere in their winter/spring Lamb from NZ is exported widely and the main markets are in northern period, supplying the market during a period of low local lamb supply. hemisphere countries, with the largest single market being the United Kingdom (UK). This means a long transportation distance to markets with Why Undertake a Lamb Carbon associated costs and implications for “food miles” and related greenhouse Footprint Study? gas (GHG) emissions. This paper reports on a research study on the carbon footprint (i.e., Consumer awareness about carbon footprinting of products is high in total GHG emissions throughout the life cycle of a product) of NZ lamb certain markets, and this has been led by supermarkets, particularly in the exported and consumed in the UK. It also considers the wider implications UK. This has resulted in a demand for information on the carbon footprint and context for meat production and GHG emissions reduction. of products supplied to some major supermarket chains or to intermediate businesses that supply them. For NZ exporters, interest in footprinting has International and NZ Lamb Production been accentuated by NZ’s long distance from many markets and possible concern about the related transport GHG emissions. China is the world’s largest producer of sheep meat at nearly 2 Mt, Within NZ, the government has also initiated an emissions trading followed by Australia at 0.8 Mt and NZ at 0.6 Mt (FAO, 2008). However, scheme, which has put a charge on GHG emissions from fossil fuel and electricity use. In addition, animal-related emissions from agriculture © 2011 Ledgard, Lieffering, Coup, and O’Brien. doi:10.2527/af.2011-0010 are scheduled to be phased into the scheme (MfE, 2011). These market 40 Animal Frontiers Downloaded from https://academic.oup.com/af/article-abstract/1/1/40/4638598 by Ed 'DeepDyve' Gillespie user on 10 April 2018 and domestic policy drivers have resulted in the need for producers and containers, chillers/freezers, and retail and household refrigerated exporters to be aware of their contribution to the carbon footprint of cabinets) (Ledgard et al., 2009a). products and of footprint reduction opportunities. Primary data on energy use, consumables, refrigerant leakage, wastes, and effl uent processing were collected from lamb processing plants from throughout NZ (covering more than 40% of total lambs processed). Data Carbon Footprint Methodology on typical shipping distance to the UK (20,750 km) were combined with a An attributional life cycle assessment (LCA) approach (e.g., conservatively high emission factor for refrigerated container shipping of Thomassen et al., 2008) was used to estimate the carbon footprint of 0.05 kg of CO -equivalents (CO eq.)/tkm (including fugitive emissions 2 2 NZ lamb exported by ship to the UK, cooked, and consumed by a UK of refrigerants) to estimate shipping GHG emissions. Secondary data were household and including waste (uneaten lamb and sewage) stages (Figure used in estimating GHG emissions from retail (Carlsson-Kanyama and 1). The functional unit was 1 kg of processed NZ lamb meat purchased Faist, 2000), household (including cooking; Foster et al., 2006), and waste by a UK consumer. stages. Emissions associated with the production of capital items, transport Emphasis was on the whole life cycle and applying methods that of consumers to and from the point of retail purchase, and changes in soil complied with ISO14044 (BSI, 2006) and PAS2050 (BSI, 2008), carbon were all excluded (according to PAS2050; BSI, 2008). particularly since the UK is a major market for NZ lamb. To conform to PAS2050, customer travel was excluded but sensitivity analysis was used Main Findings and Life Cycle Implications to examine effects of its inclusion. Survey data from Beef + Lamb NZ (B+LNZ, 2010) covering more The carbon footprint averaged 19 kg of CO eq./kg of lamb meat, with than 400 sheep and beef farms throughout NZ was used to calculate GHG 80% from the cradle-to-farm-gate (mainly animal methane and nitrous emissions from different farm classes and to determine an NZ weighted oxide emissions), 3% from processing, 5% from all transportation stages average. Animal production data were used in an energy-based (tier 2) (predominantly from shipping), and 12% from retailer/consumer/waste model (Clark et al., 2003) to estimate dry matter intake for the sheep stages (dominated by retail storage and home cooking; Figure 2; Ledgard et breeding and lamb production system. Biophysical allocation (e.g., Flysjö al., 2009a, 2010). Thus, all stages throughout the life cycle contribute to GHG et al., 2011) was used to allocate GHG emissions between animal types, emissions and can contribute to reduction of the carbon footprint. Sensitivity and economic allocation (5-year average) was used to allocate between analysis was used to examine effects of alternative practices at all stages of the lamb, mutton, and wool production from sheep. New Zealand-specifi c life cycle. At the consumer stage, inclusion of consumer transport to purchase emission factors for methane (enteric and fecal), and nitrous oxide from the meat added up to 7% to the total carbon footprint depending on the mode excreta and leached N were used based on the NZ GHG Inventory (MfE, of transport and food purchasing practices. The method of cooking by the 2007). Other emissions accounted for included embodied CO emissions consumer was also important with cooking-related emissions being 20% from electricity and fuel use, CO from fertilizer production and urea greater by roasting the lamb compared with frying it. and lime application to soil, and refrigerant emissions (from refrigerated At an NZ lamb processor level, emissions were most dependent on energy source, energy use effi ciency, and effl uent processing system. For Figure 1. Simplifi ed system diagram showing the main life cycle stages, inputs, outputs, fl ows, and coproducts. July 2011, Vol. 1, No. 1 41 Downloaded from https://academic.oup.com/af/article-abstract/1/1/40/4638598 by Ed 'DeepDyve' Gillespie user on 10 April 2018 Figure 2. Relative contribution from the main life cycle stages to the carbon footprint of New Zealand (NZ) lamb consumed in the United Kingdom (UK; Ledgard et al., 2010). example, moving from an anaerobic waste water system to an aerobic Thus, the largest opportunity to reduce GHG emissions on-farm is to increase one could potentially decrease processing GHG emissions by up to 30%. the effi ciency of feed conversion into lamb meat. This has been occurring In practice, improvements at most NZ lamb processing plants have been steadily over time as evident from the reduction in methane emissions per made over time by shifting from anaerobic pond processing of effl uent kilogram of sheep meat produced in NZ (Figure 3). The main reasons for (with associated methane emissions) to land application and using the this are an increase in the lambing percentage of ewes (from about 100% in waste as a nutrient source for grass growth. Similarly, processors have early 1990s to 125% in 2008), increased growth rate of lambs, and fi nishing increased energy use effi ciency and moved away from burning coal to the lambs at heavier weights (Morris, 2009). Thus, in 2009, NZ sheep farms use of gas or other energy sources. One processor (Silver Fern Farms, NZ) produced slightly more lamb meat by weight compared with 1990, but from has recently switched to the use of a Bubbling Fluidised Bed boiler, which a 43% smaller national fl ock (B+LNZ, 2010). This has been estimated to is able to utilize sludge from waste water treatment and woodchips as fuel coincide with a reduction in GHG emissions from cradle-to-farm-gate by sources instead of coal, which had been used. approximately 22% (Ledgard et al., 2010). Ongoing improvement in the NZ Technological changes can affect the supply chain and the carbon sheep sector is also occurring through an increase in the proportion of ewe footprint. For example, lamb has traditionally been frozen and shipped to hoggets mated (again resulting in more lamb production for each kilogram the UK, but in the past decade there has been a large increase in vacuum- of feed eaten by the breeding fl ock). In practice, the main driver of these packed chilled lamb providing increased quality and shelf-life of up to 14 reductions in GHG emissions is the need for increased farm profi tability weeks. Sensitivity analysis indicated that the chilled lamb supply chain through increased on-farm effi ciency. used less energy compared with the freeze chain, but it only decreased the Sensitivity analyses indicated limited ability to reduce the carbon total carbon footprint by approximately 0.7%. footprint by targeting other sources of on-farm GHG emissions. One In the transportation stages, shipping was the main contributor to total possibility examined was to cease use of N fertilizer on farm because transport-related emissions. However, it was also identifi ed as being very it has high manufacturing-related emissions (e.g., Ledgard et al., 2011). effi cient, with emissions per ton per km (excluding refrigeration) at about However, bearing in mind the current very low N fertilizer use on NZ 0.01 kg of CO eq. compared with about 0.08 for trucking and 0.3 for farms and the reduced productivity from ceasing its use, the effect was a household car (based on various modeled analyses). In this study, a calculated to be a reduction in carbon footprint of <1%. Nevertheless, conservatively large emission factor was used for shipping refrigerated where N fertilizer use is signifi cant, the integration of clovers in pastures containers of 0.05 kg of CO eq. per ton per kilometer (including backhaul that can fi x atmospheric N and replace N fertilizer has the potential 2 2 of an empty container), whereas others have used values of less than one- to greatly reduce fossil fuel use and decrease the carbon footprint. For half of this (e.g., 0.018 by Williams et al., 2008). Thus, the food-miles example, Ledgard et al. (2009b) estimated a 12% reduction in carbon −1 −1 associated with transportation of product to market were only a minor footprint for an NZ dairy system receiving 160 kg of N·ha ·year by contributor to the total carbon footprint. substituting fi xed-N for fertilizer-N. Farm GHG Emissions and Reduction How Does the Carbon Footprint of NZ Lamb Opportunities Compare with That from Other Studies? There have been few other studies that have examined the carbon The cradle-to-farm-gate stage was the main contributor to the carbon footprint of lamb, and they have all stopped at the farm-gate or the retail footprint, and this was predominantly from animal-related methane and distribution center. For the carbon footprint from the cradle-to-farm-gate, nitrous oxide emissions (comprising 72% of the total carbon footprint). 42 Animal Frontiers Downloaded from https://academic.oup.com/af/article-abstract/1/1/40/4638598 by Ed 'DeepDyve' Gillespie user on 10 April 2018 2-fold. Paradoxically, the least emissions were from Merino sheep produced on high country, even though they had the least effi ciency of productivity (i.e., least lambing percentage, lamb growth rates, and fi nishing body weights). This was simply an artefact of economic allocation being used, with greater allocation of total sheep emissions to wool (and therefore less to meat) for Merinos due to their much greater monetary returns per kilogram of wool compared with that for the strong wool (used for carpets) produced by other NZ sheep breeds. The magnitude of a carbon footprint will depend on the range of coproducts produced and their value or signifi cance or both. Lamb produces a range of coproducts including meat, wool, hide (used for making leather), blood, offal (some components representing delicacies for certain cultures, such as stomach lining or tripe), tallow (with a range of uses including for Figure 3. Calculated methane emissions from New Zealand average sheep meat biofuels), and renderable components that are processed into products, such based on B+LNZ (2010) data and use of the New Zealand greenhouse gas inventory as animal feeds. If the latter 4 coproducts were worthless and went to waste methodology (MfE, 2007). (e.g., to landfi ll or to the effl uent system, as had happened to a varying extent in the past), then a greater component of total lamb GHG emissions estimates for various studies in kilograms of CO eq. per kilogram of lamb would be allocated to meat. Whereas the use of economic allocation may body weight were 12.9 or 51.6 for 2 Welsh case study farms (Edwards- accentuate these differences, other allocation methods such as system Jones et al., 2009; the high value was due mainly to specifi c peat soil expansion will also be infl uenced by coproducts with other uses and value. N O emissions), 10 for an average Irish farm system (Casey and Holden, However, meat is the most valuable product from lamb and currently the 2005), and 8.6 in the current study. Williams et al. (2008) estimated GHG nonmeat coproducts may constitute about 50% or more of the body weight emissions to a UK retail distribution center for lambs produced in the UK but usually provide less than 20% of total economic returns. or NZ at 14.1 and 11.6 kg of CO eq./kg of lamb product, respectively. However, it must be noted that there were differences in methodology across How Does the Carbon Footprint of Lamb all of these studies, particularly for methane estimation method (e.g., tier 1 Compare with That of Beef or Other Meats? versus tier 2 methods; IPCC, 2006), different Intergovernmental Panel on Climate Change (IPCC) emissions factors, different system boundaries, Generic studies comparing meat types have generally shown much and different allocation methods. This means that the values outlined smaller carbon footprint values (by about 5- to 10-fold) for white meats above cannot be directly compared, although Williams et al. (2008) from nonruminants (pigs, poultry) than for red meat from ruminant applied the same methodology in comparing lamb from 2 countries. The animals (e.g., Dalgaard et al., 2007; Williams et al., 2008). A key factor in strong impact of methodology highlights the need for research papers to this difference is the enteric methane emissions from forage digestion by report all methods and data used so that others might recalculate a carbon ruminant animals. footprint for comparative purposes. There are many more published studies on the carbon footprint of More importantly, the variability between studies in the methods used beef than of lamb. For the cradle to-farm-gate stage, most beef studies emphasizes the desirability of defi ning and agreeing on a methodology are within the range of 7 to 19 kg of CO eq./kg of body weight, with such as through product category rules (BSI, 2008). This is particularly results infl uenced greatly by methodological differences as well as by important in methodology aspects for products where there is a strong farm system differences. The study of Williams et al. (2008) included infl uence on the fi nal carbon footprint value (e.g., for allocation between evaluation of the carbon footprint for UK beef and lamb based on coproducts). The International Dairy Federation recently released a generic models that accounted for the range of farm systems that exist. common methodology for dairy carbon footprinting through a common Their estimate for GHG emissions per kilogram of body weight for process involving international dairy companies and LCA researchers, the cradle-to-farm-gate stage for average UK lamb was only 57% of and this represents an ideal process. The International Meat Secretariat has that for the average UK beef. Similarly, our recent carbon footprint supported the same approach to be developed for a common methodology studies also showed smaller carbon footprint values for average NZ for lamb carbon footprinting, and this is currently underway. lamb than for NZ beef (average for traditional suckler breeding and bull beef systems), at 8.6 and 10.5 kg of CO eq./kg of body weight, What Factors Influence Variability respectively (Ledgard et al., 2010; M. Lieffering, S. Ledgard, M. Boyes, and R. Kemp, AgResearch, New Zealand, unpublished). This smaller Between Studies? carbon footprint for lamb can be attributed to greater fecundity in sheep As well as differences in methodology between studies, the carbon (e.g., 125% lambing by ewes compared with 95% calving by breeding footprint of lamb can vary with the farm system used and between cows), greater average growth rates in lambs, and wool as a coproduct individual farms. Similarly, there will be variation between different from sheep. However, it must also be recognized that in most countries processors’ contribution to the footprint (e.g., by about 2-fold per kilogram a signifi cant component of the beef is derived from cull dairy cows, of lamb processed in the current study) and at other stages, including in which have a small carbon footprint, and in NZ its inclusion brings the retail and consumer practices. weighted average carbon footprint for beef at the farm-gate down to the The few individual case farms and farm types examined in the current same value as that for lamb. This further highlights the importance of study showed variation in cradle-to-farm-gate GHG emissions of about July 2011, Vol. 1, No. 1 43 Downloaded from https://academic.oup.com/af/article-abstract/1/1/40/4638598 by Ed 'DeepDyve' Gillespie user on 10 April 2018 (Schipper et al., 2010), and similar conclusions were drawn from French accounting for whole production systems and coproducts when carrying research in temperate grasslands (Sousanna et al., 2004). More research out a carbon footprint analysis. is needed to better understand processes affecting this and the temporal The carbon footprint values outlined above all refer to averages for pattern of carbon accumulation so that it can be appropriately accounted different systems or countries. In practice, there is a large variation between for in carbon footprinting. Additionally, large losses of CO occur from individual farms within a farm system or country, and this variation is cultivation during crop production due to oxidation of soil carbon, likely to overlap the apparent differences between the published averages. whereas the carbon in grassland soils is important for carbon retention. Although some of this variation between farms is due to inherent site factors and therefore is unmanageable, much of it can be attributed to differences in farm management practices and provides opportunities for improvement. Concluding Comments Low environmental impacts, including a low carbon footprint, A Carbon Footprint Is Just One should be one goal in our quest for effi cient food production systems Environmental Indicator from our global landscapes. Sheep farming systems are important because they utilize diffi cult grassland landscapes with limited other Whereas lamb and other red meats have a greater carbon footprint than uses and the lamb produced from it is a valuable niche source of red white meats, there are context issues and other environmental indicators meat globally. From an exporting nation’s perspective, NZ provides that should be considered in assessing the wider sustainability of food a complementary out-of-season supply of quality lamb to northern products. Pigs and poultry are generally fed on grains from crops on hemisphere countries with effi ciency goals including a low total carbon land that could alternatively be used for crops for direct consumption footprint. From a global perspective of limiting GHG emissions, there by humans. In contrast, ruminants can utilize feed sources that cannot is a desire for low carbon footprint food systems irrespective of the be utilized by nonruminants, and in the case of sheep this is largely source of supply, provided other acceptable standards of food quality, grassland that is on land unsuitable for cropping. For example, in the UK environment, and welfare are met. This places pressure on exporters the latter includes upland and hill areas, whereas in NZ it also includes to be able to supply product into overseas markets with a low total steep hill country and high-altitude tussock country. This land is generally carbon footprint and consequently on achieving ongoing reductions in unsuitable for other food production purposes. the carbon footprint of their products. Life cycle assessment is widely used in determining the carbon The study of the carbon footprint of NZ lamb covered all the “cradle- footprint of products, but it is also a useful tool for examining resource use to-grave” stages, and more whole life cycle studies are required for other effi ciency and other environmental indicators. Food production based on animal and food options. The lamb study showed that GHG emissions low energy use, and particularly low fossil fuel use, is desirable to ensure are dominated by utilization of grassland by sheep at the farm stage. supplies of fossil fuels are available for other more critical requirements. However, it also showed that there have been large gains in effi ciency, Lamb production from long-term grasslands typically has low fossil fuel with a reduction in the carbon footprint over time at the farm level of over use compared with that from intensive agriculture such as dairy farming. 20% since 1990. Other contributors, including consumers, to the carbon For example, in the NZ lamb study the average fossil fuel use was 26 MJ/ footprint of the lamb life cycle can also reduce the footprint through kg of protein produced to the farm-gate stage in comparison with about improved technological, management, and behavioral practices. 210 MJ/kg of protein for milk produced in the Netherlands (Thomassen et al., 2008). Acknowledgments Lamb production on grasslands also has a low impact on water quality. In NZ the average N concentrations in waterways measured in sheep- The authors thank James McDevitt (Scion, Wellington, New −1 −1 dominant catchments equated to an N loss of 3 kg of N·ha ·year , which Zealand) and Mark Boyes (AgResearch, Hamilton, New Zealand) was less than that in catchments dominated by other livestock types, but for their contribution to life cycle assessment modeling; Robert Kemp −1 −1 greater than the 2 kg of N·ha ·year from forest catchments (McDowell for data collection; the New Zealand meat processing companies and and Wilcock, 2008). The average for NZ dairy catchments was about 27 Beef+LambNZ (Wellington, New Zealand) for data; and Ministry of −1 −1 kg of N·ha ·year , and NZ studies with cereal crops have shown similar Agriculture and Forestry (Wellington, New Zealand), Meat Industry N leaching rates to that for dairying. Although there was less difference Association (Wellington, New Zealand), Landcorp (Wellington, New across catchments and livestock types in phosphorus loss to waterways, Zealand), and Ballance Agri-nutrients (Mount Maunganui, New Zealand) sheep catchments again had the least losses (other than forests). for project support. Another feature of landscapes grazed by sheep is the relatively high biodiversity. In NZ, most sheep farms have signifi cant areas of Literature Cited native or planted trees, particularly on steeper and erosion-prone areas. B+LNZ. 2010. Compendium of New Zealand Farm Facts. 34th ed. April 2010. Although offsetting of GHG emissions is not included in carbon footprint Beef + Lamb New Zealand Publication No. P10013. analyses, at an individual farm and national GHG inventory level the BSI. 2006. EN ISO 14044:2006. International Standard. Environmental recently forested areas represent signifi cant carbon sinks. All carbon management–Life cycle assessment–Requirements and guidelines. ISBN 0 580 footprint analyses discussed in this paper take no account of carbon 49022X. 46p. BSI. 2008. Publically Available Specifi cation PAS2050–Specifi cation for the sequestration, in keeping with requirements of the PAS2050. However, assessment of the life cycle greenhouse gas emissions of goods and services. some carbon footprint protocols are reviewing possible inclusion of British Standards Institution. October 2008. 36p. carbon sequestration in soil. Surveys of soil carbon status on sheep and Carlsson-Kanyama, A. and M. Faist. 2000. Energy use in the food sector: A data beef farms on NZ hill country have shown that amounts are increasing survey. Environ Strategies Res - fms, 36 p. Stockholm, Sweden. 44 Animal Frontiers Downloaded from https://academic.oup.com/af/article-abstract/1/1/40/4638598 by Ed 'DeepDyve' Gillespie user on 10 April 2018 Casey, J. W., and N. M. Holden. 2005. Holistic analysis of GHG emissions from Irish livestock production systems. Paper No. 54036. Am. Soc. Agric. Biol. About the Authors Eng., Tampa, FL, USA. Stewart Ledgard is a principal scientist with Clark, H., I. Brookes, and A. S. Walcroft. 2003. Enteric Methane Emissions AgResearch and an adjunct professor of the from New Zealand Ruminants 1990–2001 Calculated Using an IPCC Tier 2 Life Cycle Management Centre at Massey Approach. Report for the NZ Ministry of Agriculture and Forestry, Wellington, University in New Zealand. His research New Zealand. focus is the management of resource use and Dalgaard, R., N. Halberg, and J. E. Hermansen. 2007. Danish pork production: environmental impacts of pastoral farming An environmental assessment. DJF Animal Science, 82. University of Aarhus, systems. During the past decade, this has Denmark. 38p. involved application of life cycle assessment Edwards-Jones, G., K. Plassmann, and I. M. Harris. 2009. Carbon footprinting of across a range of New Zealand agricultural lamb and beef production systems: Insights from an empirical analysis of farms systems and products. Ledgard has researched in Wales. J. Agric. Sci. 147:707–719. the design of resource-effi cient systems and FAO. 2008. FAOSTAT. Trade. Accessed Dec. 13, 2010. http://faostat.fao.org/ has worked widely with agricultural sectors site/342/default.aspx. to evaluate products throughout their export- Flysjö, A., C. Cederberg, M. Henriksson, and S. Ledgard. 2011. How does co- driven supply chain. He is involved in a range product handling affect the Carbon Footprint of milk?–Case study of milk of international collaborative projects on life cycle management. production in New Zealand and Sweden. Int. J. Life Cycle Assess. 16:420–430. Correspondence: stewart.ledgard@agresearch.co.nz Foster, C., K. Green, M. Bleda, P. Dewick, B. Evans, A. Flynn, and J. Mylan. 2006. Environmental impacts of food production and consumption. A report to the Department for the Environment, Food and Rural Affairs, Manchester Business Mark Lieffering currently works as a senior School, Manchester, United Kingdom. scientist for AgResearch in Palmerston IPCC. 2006. 2006 IPCC Guidelines for National Greenhouse Gas Inventories: North, New Zealand. Lieffering’s research Volume 4: Agriculture, Forestry and other Land Use. Intergovernmental Panel encompasses a wide variety of topics on Climate Change, Paris, France. Accessed May 10, 2011. http://www.ipcc- related to the impacts of global change on nggip.iges.or.jp/public/2006gl/vol4.htm. pastures and adapting agricultural systems Ledgard, S. F., M. Boyes, and F. Brentrup. 2011. Life cycle assessment of to meet future challenges. His work includes local and imported fertilisers used on New Zealand farms. In Adding to the experimentally investigating and modeling Knowledge Base for the Nutrient Manager. L. D. Currie and C. L. Christensen, the effects of elevated CO and warming ed. Occasional Report No. 24, Fertilizer and Lime Research Centre, Massey on pasture processes as well as researching University, Palmerston North, New Zealand. (In press). the carbon and water footprints of products Ledgard, S. F., M. Lieffering, J. McDevitt, M. Boyes, and R. Kemp. 2010. A derived from grazing pastures of animals. greenhouse gas footprint study for exported New Zealand lamb. Report for Meat Industry Association, Ballance Agri-nutrients, Landcorp and MAF. AgResearch, Hamilton, New Zealand. 26p. Ledgard, S. F., J. McDevitt, M. Boyes, M. Lieffering, and R. Kemp. 2009a. Dan Coup is trade and economic manager Greenhouse gas footprint of lamb meat: Methodology report. Report to MAF. for the Meat Industry Association of New AgResearch, Hamilton, New Zealand. 36p. Zealand, the organization representing New Ledgard, S. F., R. Schils, J. Eriksen, and J. Luo. 2009b. Environmental impacts of Zealand meat packers and exporters. Dan grazed clover/grass pastures. Isr. J. Agric. Res. 48:209–226. has a background in biological sciences McDowell, R. W., and R. J. Wilcock. 2008. Water quality and the effects of different and economics. His current role focuses on pastoral animals. N. Z. Vet. J. 56:289–296. trade policy but also incorporates climate MfE. 2007. “New Zealand’s Greenhouse Gas Inventory 1990–2006: An Overview” change policy issues, including New N. Z. Ministry for the Environment report No. ME872. Wellington, New Zealand’s domestic cap and trade legislation, Zealand. and product-level carbon footprinting for MfE. 2011. Agriculture in the Emissions Trading Scheme. Ministry for the overseas customers. Environment. Accessed May 10, 2011. http://www.climatechange.govt.nz/ emissions-trading-scheme/participating/agriculture/. Morris, S. T. 2009. Economics of sheep production. Small Rumin. Res. 86:59–62. Ben O’Brien is general manager of Market Schipper, L. A., R. L. Parfi tt, C. Ross, W. T. Baisden, J. J. Claydon, and S. Fraser. Access at Beef + Lamb New Zealand, which 2010. Gains and losses of C and N stocks in New Zealand pasture soils depend is the representative body of New Zealand’s on land use. Agric. Ecosyst. Environ. 139:611–617. sheep and beef farmers. He has responsibility Sousanna, J.-F., P. Loiseau, N. Vuichard, E. Ceschia, J. Balesdent, T. Chevallier, for managing his organization’s activities in and D. Arrouays. 2004. Carbon cycling and sequestration opportunities in trade policy and technical issues, including temperate grasslands. Soil Use Manage. 20:219–230. sustainability. O’Brien has worked in Thomassen, M. A., R. Dalgaard, R. Heijungs, and I. J. M. de Boer. 2008. the New Zealand meat industry for more Attributional and consequential LCA of milk production. Int. J. Life Cycle than 20 years covering a wide range of Assess. 13:339–349. responsibilities including research and Williams, A., E. Pell, J. Webb, E. Moorhouse, and E. Audsley. 2008. Comparative development and quota management. He is life cycle assessment of food commodities procured for UK consumption a member of the International Meat Secretariat’s Sustainable Meat Committee through a diversity of supply chains. DEFRA Project FO0103. and has an interest in promoting a single international greenhouse gas life cycle Zygoyiannis, D. 2006. Sheep production in the world and in Greece. Small Rumin. analysis methodology for lamb.  Res. 62:143–147. July 2011, Vol. 1, No. 1 45 Downloaded from https://academic.oup.com/af/article-abstract/1/1/40/4638598 by Ed 'DeepDyve' Gillespie user on 10 April 2018

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Animal FrontiersOxford University Press

Published: Jul 1, 2011

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