Climate Smart Norwegian Sheep Production

Norway has large unused outfield resources that are crucial for increasing food production in line with human population growth. This requires the use of ruminants, while agriculture must simultaneously reduce its greenhouse gas emissions (GHGs). The challenge is to combine increased ruminant production based on outfield grazing with lower GHG emissions. There is a lack of research-based knowledge on the levels and variation in GHG emissions from Norwegian sheep farms. The project "Climate-Smart Norwegian Sheep Production" aimed to contribute to sustainable, climate-smart sheep production by developing a farm model, HolosNorSheep, to calculate GHG emissions from Norwegian sheep farms. The HolosNorSheep model is based on data from various sources, such as the Sheep Recording System and Account Results etc., to ensure it is representative of Norwegian conditions. The model considers variations in natural resources, pasture types, animal performance, and slaughtering of lambs in different batches. It includes several sub-models to calculate emissions from different sources. Enteric methane is estimated based on feed intake calculated using a feed planning tool developed by Nortura’s advisory service. Methane and nitrous oxide from manure storage and spreading are calculated using the methodology in the national emissions inventory. The model also includes emissions from the production of inputs like mineral fertilizer, concentrats, and fuel, as well as the soil carbon balance. HolosNorSheep calculates the total GHG emissions from the farm and allocates them per kilogram of produced unit (wool and carcass), known as emission intensities. For five geographical regions of Norway (East, West, South, Central, and North), the emission intensity for carcass varied from 24 kg CO2-equivalents in Central Norway to 27 kg CO2-equivalents in Northern Norway, while corresponding figures for wool were 20 to 23 kg CO2-equivalents per kilogram. Enteric methane was the largest emission source, accounting for 44-51% of the total, followed by nitrous oxide from soil (15-19%). The differences between North and Central Norway are mainly due to higher consumption of fuel and mineral fertilizer in Northern Norway, resulting from shorter growing seasons and lower roughage yields, which increase the need for cultivated land. Based on the geographic distribution of the sheep population, weighted emission intensities for meat and wool were calculated to be 25 and 23 kg CO2-equivalents, respectively. In collaboration with “Landbrukets Klimaselskap”, HolosNorSheep has been adopted as a Climate Calculator for Sheep, which serves as a basis for GHG calculations and advisory services at the farm level. HolosNorSheep was tested on 38 pilot farms with a wide range of geographical locations, production results, and resource bases. Most pilot farms had data for several years (2-3 years). The analyses showed significant variation in emission intensities, ranging from 15 to 27 kg CO2-equivalents, indicating potential for emission reductions through various mitigation measures at the farm level. Due to the many influencing factors and limited data, it was however not possible to isolate the effect of individual factors on GHGs. HolosNorSheep was also used to investigate the impact of alternative management practices, such as increased lamb growth, reduced lamb loss, reduced age at first lambing, and increased ewe longevity, on resource use (feed efficiency and concentrate use) and GHGs per kilogram of carcass. The results showed that reducing lamb loss decreased the carbon footprint and feed consumption per kilogram of carcass. Increasing lamb growth up to 300 grams per day reduced emission intensity and improved feed efficiency, but increased concentrate feed use per kilogram of carcass. Further growth to 325 grams per day increased both emission intensity and concentrate use. Reducing the average age at first lambing to one year reduced emission intensity and improved feed efficiency but increased concentrate feed use. The optimal longevity for ewes depended on the metric being considered: two years for feed efficiency, five years for emission intensity, and seven years for concentrate use. The results clearly show that trade-offs between GHG, resource use, and feed-food competition must be considerer before implementing climate measures. HolosNorSheep was also used in the “Grass to Gas” project (Strategies to Mitigate GHG Emissions from Pasture-Based Sheep Systems, funded by JPIFACCE- Agriculture, Food Security, and Climate Change). This work closely aligned with the goals of this project, where two breeds with different management practices were compared: the Norwegian White Sheep (NWS) and the Old Norwegian Spæl (ONS). These two breeds differ significantly in terms of size and performane (e.g., number of weaned lambs per ewe and lamb growth). NWS was found to have lower emission intensity per kilogram of carcass and wool than ONS.

The "Climate Smart Norwegian Sheep Production"-project have contributed with the whole-farm GHG systems analysis model HolosNorSheep, and by the application of this model, new science-based knowledge regarding the levels and variations of GHGs from sheep production systems in Norway and the effect of various mitigation strategies. This may contribute to achieving political goals of reducing the environmental impacts of the agricultural sector while at the same time maintaining self-sufficiency and food security through utilization of natural resources such as outfield pastures by sheep grazing. Maintaining sheep production in rural areas is important not only for farmers, but also for associated service industries and for fulfilling the political goal. Well-managed sheep production is important to preserve cultural landscapes and biodiversity, as well as directly or indirectly support regional tourism (e.g., niche products, open landscapes). The HolosNorSheep-model have been implemented into a GHG calculator, which are used by the advisory services to reduce GHG emissions on Norwegian sheep farms. Consumers will benefit from sheep meat being produced more cost-efficiently and with less feed-food competition due to higher feed efficiency, lower environmental impact and lower concentrate use. This may lead to a higher acceptance of Norwegian sheep production.

Norway has set political goals to increase domestic food production based on domestic resources in line with the population growth, while at the same time reducing the greenhouse gas (GHG) emissions from agriculture (currently 8% of total domestic GHG emissions). The agricultural area is small, 3% of the total land area. Cereals are only grown on one-third of this area, due to constraints in climate and topography. The rest of the area (66%) is cultivated grass production. In addition, substantial valuable feed resources are located in outfields, i.e. uncultivated vegetation in the forests and mountains. These areas (140 000 square km) represent a 50% unexploited grazing capacity, corresponding to 3.6 million sheep. Thus, utilization of natural feed resources is inevitably related to ruminant livestock, which is a challenge in relation to reducing GHG emissions. This project aims to contribute to a sustainable, climate smart sheep production based on exploitation of national feed resources, including outlying pastures, combined with lowest possible climate impacts. The project goals will be reached by developing a farm-scale model for the estimation of GHG emissions from Norwegian sheep production.Further, the model will be used as a tool to identify factors related to animals and management that are of relevance for the on-farm GHG emissions. This can be used as a basis for mitigation options to reduce the environmental impact of the sheep meat production. Finally, the project will examine how alternative sheep production systems will affect GHG emissions and use of resources, and recommend mitigation strategies to reduce GHG emissions from Norwegian sheep farms.