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Denne publikasjonen presenterer en ny metodikk for estimering av endringer i lageret av jordkarbon som følge av arealbruksendringer på mineraljord. Metodikken er utviklet for bruk i den nasjonale rapporteringen av arealbrukssektoren under FNs klimakonvensjon. Metodikken baserer seg på den enkleste tilnærming i følge IPCC sine retningslinjer, en såkaldt Tier 1. Tier 1 metodikken baseres i stor grad på standardverdier fra retningslinjene (IPCC default), men trenger en kopling mot nasjonal arealinformasjon. Denne koplingen beskrives i rapporten. Metodikken tar utgangspunkt i standardverdier for lageret av jordkarbon (SOCREF). Disse er basert på jordtype-grupperinger og klimasone som stammer fra en verdensdekkende jorddatabase. Endringer i jordkarbon etter arealbruksendring estimeres ved hjelp av SOCREF i kombinasjon med et sett faktorer (også standardverdier) som er arealbruksavhengige. Metodikken legger til grunn at endringer i jordkarbon skjer lineært over 20 år (ifølge 2006 IPCC Guidelines). Grunnleggende informasjon for å kunne kople standardverdier mot arealer på en konsistent måte er stort sett manglende for Norge på nasjonal skala. Rapporten gir derfor detaljert informasjon om de datakildene som har vært brukt til å kunne definere hvilke standariserte verdier som tilhører et bestemt areal i overgang....

The 1975 and 1992 versions of Soil Taxonomy, the 1988 version of the FAO-Unesco system, and the 1987 version of the Canadian System of Soil Classification were used to classify seven sandy soils with different degrees of podzolization. None of the soils were classified as Spodosols according to the I975 version of Soil Taxonomy, three were classified Spodosols according to the Keys to Soil Taxonomy 1992, five as Podzols according to the FAO-Unesco system and two were classified as Podzolic according to the Canadian system. The exclusion of soils from the Podzol (Spodosol) orders was due to depth or thickness requirements for the podzolic (spodic) horizon. Indexes based on properties of the mineral soil were used to evaluate the degree of podzolization. Cluster analyses of these indexes were used to group the soils. Comparisons between these groups and the different classifications suggested that the difference in soil development were reflected best by the 1992 version of Soil Taxonomy. A cluster analysis based on the upper podzol B subhorizon properties suggested that the difference in podzol development were best reflected by the Canadian classification.

Utilization of the outfield for grazing have long traditions in Norway. Not only as a pasture, but also mowed to provide food for the winter (Rekdal & Angeloff, 2021). From 1949 to 1999, grazing in Norway changed from being dominated by livestock to being equally grazed between wild herbivore and livestock (Austrheim et al., 2011). This change in usage has led several of the semi-natural habitat types to end up on the red list of the Norwegian Biodiversity Information Centre, such as Semi-natural meadow and Hayfields (Hovstad, 2018). Therefore, grazing in outfield areas in Norway are desired as a way of keeping the cultural landscape. Resent years events particularly, in addition to a growing concern about the world’s food situation has increased the interest for local food production. The latest analysis of grazing and the outfield suitable of such, indicates that Norway’s unused potential in outfield is about 55% (Rekdal & Angeloff, 2021). In addition to recent years events, the world is facing changes in climate. Still debated on how extensive and where the greatest changes will appear, a change in food production are required to undergo adjustments. Knowledge of management and “best practice” models are therefore crucial. Also in Norway, information on how the soil in outfields are affected by grazing is as important than ever. In this thesis five locations who differs in climate and vegetation are sampled. All these locations are grazed during the summer season by suckler cows which is a part of the Norwegian meat production. Throughout this thesis grazing was not found to significantly affect the SOC-stock, SOC concentration or the thickness of the organic layer. While grazing was found to significantly decrease the HWEC-stock in all mineral layers and the CN-ratio in the organic layer. The decrease in the HWEC-stock is suggested caused by removal of organic matter by grazers. The basis for this assumption is partly the combination of the significant decline in HWECstocks and difference between grazed and non-grazed site in the thickness of the organic layer mean values (not significant). In addition, the CN ratio was found to significantly decrease under grazing in the organic layer. The HWEC-stock is viewed as a measure of the labile fraction (Dong et al., 2021), and is a useful indicator of the soil quality in soil-plant ecosystems (Ghani et al., 2003). The form and behaviour of the SOM and SOC is fully reliant on microbial mass (Bhattacharyya et al., 2022), and a decrease of the HWEC might therefor be a sign that a decline of microbial biomass pool (Ghani et al., 2003) are taking place. Since a significant decrease were found between the grazed site and the control sites (non-grazed) it might be an early indicator of degradation of the soil structure. A significant increase in bulk density between sites in the two top layers (the organic layer, mineral 0-10 cm) were found for all locations. In accordance with other studies on grazing effects (Byrnes et al., 2018; Martinsen et al., 2012; Piñeiro et al., 2010), it was concluded that the pastures were influenced by the grazing animals. On the background of different utilizing periods and grazer densities, the management of the pastures is suggested to might be influencing the HWEC-stock. Amongst the tested factors related to geography and effect on the SOC-stock, only MAT were found significant. Precipitation and content of fine texture quantity were not found to significantly effect SOCstocks. Therefore, geography was found somewhat related to the SOC-stock. Only Mg-stock had a significant difference between sites. Grazing was not found to significantly affect the soil’s pH. No plausible explanation for this significant result was found. The other macronutrient stocks were not found to significantly change with grazing. Beiting i utmark har lange tradisjoner i Norge. Ikke bare er utmarka benyttet som beite, men ble før også slått for å skaffe dyrene mat til vinteren (Rekdal & Angeloff, 2021). Fra 1949 til 1999 endret beite i Norge seg fra å være dominert av husdyr til å bli likt beitet mellom ville dyr og husdyr (Austrheim et al., 2011). Denne bruksendringen har ført til at flere av de semi-naturlige naturtypene har havnet på rødlista til Artsdatabanken, som for eksempel Semi-naturlig eng og slåttemark (Hovstad, 2018). Beiting som en måte å opprettholde kulturlandskapet er en av grunnene til at beiting i den norske utmarka er ønsket. Med tanke på de siste årenes begivenheter, i tillegg til en økende bekymring for verdens matsituasjon har interessen for lokal matproduksjon økt. Den siste analysen utført på beitebruk og utmarkas egnethet for dette, indikerer at Norges ubrukte potensial i utmark er om lag 55 % (Rekdal & Angeloff, 2021). Verden står i tillegg til de siste årenes hendelser på trappene av klimaendringer. Omfang og område for hvor været vil endres mest drastisk er usikkert, men matproduksjonen vil mest sannsynlig uansett måtte omstilles og berede seg på disse endringene. Kunnskap om forvalting og «best practice»-modeller er derfor avgjørende. Kanskje viktigere enn noen gang, også i Norge, er informasjon om hvordan jorda i utmark påvirkes av beiting. I denne oppgaven er fem lokasjoner som er forskjellige i klima og vegetasjon prøvetatt. Alle disse lokalitetene beites i sommersesongen av ammekyr som er en del av den norske kjøttproduksjonen. Gjennom denne oppgaven ble det ikke beiting funnet til å signifikant påvirke det organiske karbonet i jorda (SOC-stock), konsentrasjonen av organisk karbon (SOC%) eller tykkelsen på det organiske sjiktet. I motsetning ble beiting funnet å signifikant redusere hot water extractable carbon (HWEC) signifikant i alle mineralsjikt og CN-forholdet (karbon:nitrogen) i det organiske sjiktet. M-MINA

Carbon stocks of peatlands is of growing interest due to the ability to store large amounts of carbon. To provide data of this subject this master thesis presents results from a study of a peatland within a forest nature reserve outside of Oslo, Norway. First, peat volume was estimated using a combination of ground penetrating radar survey and GIS tools (EkkoPulse software, ArcMap and Excel). Second, sediment cores retrieved from the peat were analysed in the laboratory to analyse the bulk density and carbon content of the organic material and to calculate the carbon stock of the peatland. The data were also used to explain how this peatland has developed. The volume of the total peatland analysed by the ground penetrating radar was calculated to be 6487 m3. Degree of decomposition, described by the von Post scale, shows similar trends for all four cores; it is low in the shallow peat and increases with depth where they stabilize at level 6-8. Using Loss On Ignition as total amount of organic material gave values well above 90%, except for the samples that visibly contain minerogenic material. These results were consistent with results from total carbon analysis using LECO Truspec instrument finding total carbon content of peat core MM1to be 47-55%. The total carbon content of the remaining three cores were determined by regression analysis to be 50-53% in core MM2, 5154% in core MM3 and 52-54% in core MM4. Carbon stocks in MM1 range from 2 kgC/m2 to 7 kgC/m2. The total amount of carbon stored in this peatland is calculated to be 278 ton. For the top meter the carbon stock is 41.1 kg/m2. The hypothesis for the formation of this peatland being a depression in bedrock filled with water to form a pond, later filled with sediments and organic material was supported by the shape of the peat basin illustrated in the GPR survey, and the fine minerogenic material in the bottom part of peat core MM1. Further field observations support peatland boundary is changing, and it can be predicted that the rise in temperature and changes in precipitation might cause degradation of organic material in the peatland. This process may be part of a positive feedback loop with climate change. Karbonlager i myr er av økende interesse grunnet deres evne til å lagre store mengder karbon. For å belyse dette temaet presenterer denne oppgaven resultater fra en studie av en myr i Karlshaugen naturreservat i Nordmarka, Oslo. Volum av myra ble kartlagt ved en kombinasjon av georadar og GIS-verktøy (EkkoPuls-programvare, ArcMap og Excel). Videre ble fire sediment kjerner hentet opp fra myra, og analysert for tetthet og karboninnhold. Dette er brukt til å estimere mengde karbon lagret i myra. Basert på data fra undersøkelsen er det også utformet en forklaring på hvordan denne myra er dannet og har utviklet seg. Volumet av den delen av myra som er kartlagt med georadar er estimert til 6487 m3. Grad av nedbrytning i materialet, beskrevet ved hjelp an von Post skalaen, viser lignende utvikling i de fire kjernene. I det grunne myrmaterialet er det en lav grad av nedbrytning, mens den øker i dybden, og stabiliserer seg på nivå 6-8. Ved bruk av glødetap er mengde organisk materiale i prøvene bestemt, dette ga resultater på godt over 90%, bortsett fra de prøvene som inneholdt mineralsk materiale. Disse resultatene samsvarer med analysene for karbon innhold gjennomført ved bruk av LECO Truspec instrument. Disse viser karboninnhold på 47-55% for kjerne MM1. Karbon innholdet i de resterende kjernene er bestemt med en regresjonsanalyse, som ga resultater på 50-53% for kjerne MM2, 51-54% for kjerne MM3 og 52-54% for kjerne MM4. Karbonlager utregninger for kjerne MM1 variere fra 2 kgC/m2 til 7kgC/m2. Den totale mengden karbon lagret i denne myra er estimert til 278 tonn. For den øverste meteren i myra er karbonlageret beregnet til 41.1 kg/m2. Hypotesen for hvordan denne myra er dannet går ut på at en nedsenkning i grunnfjellet ble fylt med vann og dannet et tjern, som senere ble fylt med sedimenter og organisk materiale. Denne hypotesen er støttet av formen på myrbassenget som er godt illustrert i georadar undersøkelsen, og funn av mineral materiale i bunnen av den dypeste myrkjernen. Videre så støtter feltobservasjoner tidligere resultater om at denne myra er i endring, det kan antas at økning i temperatur og ening i nedbør kan føre til nedbrytning at organisk materiale og utslipp av karbon. Denne prosessen kan være en del av en positiv tilbakekoblingsmekanisme med globale klimaendringer. M-MINA

Glacifluvial deposits and their soil carbon stock and stability have been studied in the deglaciation landscape of Gausdal Vestfjell, Norway. Soil profiles are described and sampled for parent material clast analysis, density calculation and soil chemical analysis across a variety of glacifluvial landforms deposited in both flowing and stagnant ice, subaerially as well as subaqueously. The landforms include eskers, kame, kame terraces, delta and fan deposits. The morphology and sedimentology of 17 landforms are described and interpreted from remote sensing and field investigation. Methods have included visualization of LiDAR data in ArcMap, stratigraphic logging, sediment property analysis and Ground Penetrating Radar measurements. Calculation of carbon stock is based on soil density, stone and boulder content, horizon thickness and laboratory measurements of total carbon content. Gausdal Vestfjell was deglaciated by down-wasting of stagnant ice, where kame terraces at the highest elevations (820-890 masl) record a progressive lowering of the ice surface. Fan, delta and sandur deposits record ice-damming and gradual drainage of meltwater from the lowest elevations (778-810 masl). The glacifluvial deposits are subangular, sorted and mainly composed of sand and gravel although both finer and coarser sediments occur. The deposits are dominated by tabular and through cross bedding, current ripples and horizontal lamination, erosive surfaces and variable discharge mainly in the upper flow regime. The carbon stocks can be linked to depositional environments and processes during deglaciation. Early and late stage deposition at high (~890 masl) and low elevation (~790 masl), respectively, resulted in low carbon stocks, while deposition in stagnating ice at intermediate elevations is linked to high carbon stocks (~850 masl). The coarse texture of the deposits limits carbon input, decomposition, translocation and stabilisation due to low total particle surface area and water and nutrient retention capacity. Soil texture further exerts a major influence on carbon stocks through organic material occlusion and complexation with minerals, and a doubling of the silt and clay content from 20 % to 40 % nearly triples carbon stock. The texture varies greatly due to large variations between and within depositional environments and processes, and the glacifluvial carbon stocks are thus linked to the formation of the landforms they are found on. The carbon stock of the soils is estimated down through the Bs horizon, and ranges from ~ 3 to 18 kg/m2, with a mean estimated to 7.99 kg/m2. The fraction stored in the mineral soil is highly variable and ranges from ~10 % to ~ 100 %, averaging at 63 %. Soil organic carbon varies with the nutrition status of the nearby bedrock and parent material, the degree of soil formation and the nature of sediment transport and deposition. The degree of soil formation is higher in soils formed from innutritious parent material. The soil carbon stock is higher in soil formed on landforms composed of immature sediment, deposited in the lower flow regime and with a low relief with the surrounding landscape. Stabilisation of organic carbon in the mineral soil depends on the presence of clay minerals in the parent material and soil weathering products including iron and aluminium oxides and phyllosilicates. Mineral-stabilised carbon in soil of nutritious parent material may show higher chemical recalcitrance, while carbon stabilised in more acidic soils formed from less nutritious parent material may be more labile and to a larger degree stabilised by oxides. Upscaling of carbon stock estimates from the detailed study of selected landforms was done by georeferencing a bedrock map and a topographic map based on LiDAR data to all landforms mapped by remote sensing in the study area (c. 500). Parent material nutrition status can be inferred from the local bedrock, and the nature of deposition from the shape of landforms and their relationship with the surrounding landscape. The small number of deposits studied provides no statistical significance for extrapolation, however, the trends and variation in the carbon stocks of glacifluvial soils appear to be predictable. By upscaling, the organic horizon carbon stocks of the glacifluvial soils were estimated to be equivalent to ~121 Mg CO2/ha, and the carbon stocks of the mineral soil horizons to ~ 241 Mg CO2/ha. The former is unstable and may be lost from the deglaciation landscape to the atmosphere in a warmer climate while the latter may be lost if there is a change in land use. Overall, the landforms show large carbon stock variations for both organic and mineral soil horizons. Calculated values are comparable to values obtained in previous studies for carbon stocks of forest soils in mountainous ecosystems. Glasifluviale avsetninger og deres karbonlager er studert i isavsmeltingslandskapet i Gausdal Vestfjell, Oppland. Jordprofiler fra fire glasifluviale landformer er beskrevet, og det er tatt prøver for analyse av opphavsmateriale, jordtetthet og jordkjemiske egenskaper fra tolv landformer. Morfologien og sedimentologien til i alt 17 landformer, inkludert eskere, kame, kameterrasse, delta og vifteavsetninger er beskrevet og tolket basert på fjernanalyse og feltundersøkelse, blant annet ved fremstilling av LiDAR-data i Arc MAP, stratigrafisk logging, analyse av sedimentegenskaper og geroradarmålinger. Beregning av karbonlager er basert på jordtetthet, innhold av stein og blokk, sjikttykkelse, og laboratorieanalyse av jordas innhold av total karbon. M-MINA