Suomen poronhoitoalueen lumiolosuhteet ja niiden vaikutukset poronhoitoon.

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Can a snow structure model estimate snow characteristics relevant to reindeer husbandry?

Snow affects foraging conditions of reindeer e.g. by increasing the energy expenditures for moving and digging work or, in contrast, by making access of arboreal lichen easier. Still the studies concentrating on the role of the snow pack structure on reindeer population dynamics and reindeer management are few. We aim to find out which of the snow characteristics are relevant for reindeer in the northern boreal zone according to the experiences of reindeer herders and is this relevance seen also in reproduction rate of reindeer in this area. We also aim to validate the ability of the snow model SNOWPACK to reliably estimate the relevant snow structure characteristics. We combined meteorological observations, snow structure simulations by the model SNOWPACK and annual reports by reindeer herders during winters 1972-2010 in the Muonio reindeer herding district, northern Finland. Deep snow cover and late snow melt were the most common unfavorable conditions reported. Problematic conditions related to snow structure were icy snow and ground ice or unfrozen ground below the snow, leading to mold growth on ground vegetation. Calf production percentage was negatively correlated to the measured annual snow depth and length of the snow cover time and to the simulated snow density. Winters with icy snow could be distinguished in three out of four reported cases by SNOWPACK simulations and we could detect reliably winters with conditions favorable for mold growth. Both snow amount and also quality affects the reindeer herding and reindeer reproduction rate in northern Finland. Model SNOWPACK can relatively reliably estimate the relevant structural properties of snow. Use of snow structure models could give valuable information about grazing conditions, especially when estimating the possible effects of warming winters on reindeer populations and reindeer husbandry. Similar effects will be experienced also by other arctic and boreal species

Can a snow structure model estimate snow characteristics relevant to reindeer husbandry?

Snow affects foraging conditions of reindeer e.g. by increasing the energy expenditures for moving and digging work or, in contrast, by making access of arboreal lichen easier. Still the studies concentrating on the role of the snow pack structure on reindeer population dynamics and reindeer management are few. We aim to find out which of the snow characteristics are relevant for reindeer in the northern boreal zone according to the experiences of reindeer herders and is this relevance seen also in reproduction rate of reindeer in this area. We also aim to validate the ability of the snow model SNOWPACK to reliably estimate the relevant snow structure characteristics. We combined meteorological observations, snow structure simulations by the model SNOWPACK and annual reports by reindeer herders during winters 1972-2010 in the Muonio reindeer herding district, northern Finland. Deep snow cover and late snow melt were the most common unfavorable conditions reported. Problematic conditions related to snow structure were icy snow and ground ice or unfrozen ground below the snow, leading to mold growth on ground vegetation. Calf production percentage was negatively correlated to the measured annual snow depth and length of the snow cover time and to the simulated snow density. Winters with icy snow could be distinguished in three out of four reported cases by SNOWPACK simulations and we could detect reliably winters with conditions favorable for mold growth. Both snow amount and also quality affects the reindeer herding and reindeer reproduction rate in northern Finland. Model SNOWPACK can relatively reliably estimate the relevant structural properties of snow. Use of snow structure models could give valuable information about grazing conditions, especially when estimating the possible effects of warming winters on reindeer populations and reindeer husbandry. Similar effects will be experienced also by other arctic and boreal species

The Importance of Reindeer in Northern Finland during World War II (1939–45) and the Post-War Reconstruction

We studied the consequences of World War II (WWII, 1939–45) for reindeer herding in northern Finland, evaluated the significance of the livelihood for the population during and after the war, and identified the factors that made successful reconstruction of the livelihood possible. The study is based on qualitative content analysis of articles published in the professional journal Poromies (‘Reindeer Herder’) during the period 1931–67. Reindeer were an important source of food, transport, clothing, footwear, and skins for soldiers during the war. Approximately 220 000 reindeer were slaughtered to provide food, averting the compulsory slaughter of 88 000 cows. Herders’ skills were highly valued during the war. The herds and herders figured in the reconstruction of northern Finland and contributed to the war reparations owed the Soviet Union. During the period 1939–45 the number of reindeer fell dramatically, and the cession of Finnish territories to the Soviet Union and destruction of fences made herding difficult. In addition, the area of pastureland available to reindeer decreased. The combined effects of military operations, a labour shortage, an increased number of predators, and difficult weather and snow conditions led to losses of reindeer. The recovery of the livelihood to its pre-war level took 10 years. We argue that in addition to improved post-war pasture conditions—a result of decreased reindeer densities and favourable weather—the rapid recovery of reindeer herding can be attributed to the high motivation, diligence, and experiential knowledge of herders and the herding administration gained in rebuilding the livelihood after WWI (1914–18). Both groups understood that in northern Finland it would be economically wiser to invest in reindeer husbandry rather than cattle farming since reindeer are better adapted than cattle to the harsh climate and to forage grown in low-productive soils. Reindeer herding was based on natural pastures and labour, whereas cattle farming relied on crop cultivation, as well as expensive buildings, machinery, and fertilizers.Nous avons étudié les conséquences de la Deuxième Guerre mondiale (1939–1945) sur l’élevage des rennes dans le nord de la Finlande, évalué l’importance des moyens de subsistance de la population pendant et après la guerre et déterminé les facteurs permettant la reconstruction réussie des moyens de subsistance. L’étude est basée sur une analyse du contenu qualitatif d’articles publiés dans la revue professionnelle Poromies (« éleveur de rennes ») entre 1931 et 1967. Les rennes étaient une source importante de nourriture, de transport, de vêtements, de chaussures et de peaux pour les soldats durant la guerre. Environ 220 000 rennes se sont fait abattre pour fournir de la nourriture, évitant l’abattage obligatoire de 88 000 vaches. Les compétences des éleveurs étaient très recherchées pendant la guerre. Les troupeaux et les éleveurs ont joué un rôle dans la reconstruction du nord de la Finlande et contribué aux réparations de guerre pour dommages causés à l’Union soviétique. De 1939 à 1945, on a assisté à un déclin très important de la population de rennes; la cession des territoires finlandais à l’Union soviétique et la destruction de clôtures ont rendu l’élevage difficile. De plus, les zones de pâturage des rennes ont diminué. Les effets des opérations militaires alliés à la pénurie de main-d’oeuvre, à l’augmentation du nombre de prédateurs, aux conditions météorologiques difficiles et aux conditions de la neige ont entraîné la perte de rennes. Le rétablissement des moyens de subsistance à leur niveau d’avant-guerre a pris dix ans. Nous soutenons qu’en plus de l’amélioration des conditions de pâturage d’après-guerre (le résultat du déclin de la densité de population de rennes et de conditions météorologiques favorables), le rétablissement rapide de l’élevage de rennes peut être attribué au niveau de motivation élevé, à la diligence et aux connaissances acquises par l’expérience des éleveurs ainsi qu’à l’administration des troupeaux découlant de la reconstruction des moyens de subsistance après la Première Guerre mondiale (1914–1918). Les deux groupes ont compris que pour le nord de la Finlande, il coûterait moins cher d’investir dans les activités d’élevage de rennes plutôt que dans les activités d’élevage des bovins, car les rennes s’adaptent mieux que les bovins au climat rigoureux et au fourrage qui pousse dans les sols moins productifs. L’élevage de rennes reposait sur les pâturages naturels et le travail, tandis que l’élevage des bovins reposait sur la culture des plantes, sans compter les bâtiments, la machinerie et les engrais coûteux

Review of Polish contribution to snow cover research (1880–2017)

The purpose of this article is to present the development of multifaceted research on snow cover conducted by Polish researchers in various parts of the world since the end of the 19th century up to the modern times. The paper describes Polish studies on physical and chemical properties of snow cover, its long-term changes, relationships between snow cover and climate, impact of snow cover on environmental conditions and human activity. This work is also an attempt to show the contribution of Polish snow-related research to the international achievements in this fields

Poronhoidon tuottavuus ja ekonomia erilaisissa laidun- ja ympäristöolosuhteissa

Hankkeen päätavoite oli tutkia poronhoidon tuottavuutta ja kannattavuutta sekä ekologista ja taloudellista kestävyyttä bioekonomisen tutkimuksen avulla. Poronhoidon dynaamiseen systeemimalliin sisällytettiin laitumiin, laidunympäristöön, porokantaan ja poronhoitoon liittyvät keskeiset biologiset, poronhoidolliset ja taloudelliset muuttujat sekä niiden väliset riippuvuudet. Mallin avulla analysoitiin talvilaidunten, poromäärien, porotokan rakenteen, poronhoitokäytäntöjen sekä erilaisten menojen ja tulojen vaikutusta poronhoidon tuottavuuteen ja kannattavuuteen. Samalla tarkasteltiin optimaalisia ratkaisuja ja sopeutumisprosesseja erilaisiin laidun‐ ja lähtötilanteisiin poronhoidossa. Hankkeen toisessa osiossa selvitettiin poronhoitoon vaikuttavia lumi‐ ja kaivuolosuhteita sekä analysoitiin SNOWPACK‐mallin ja säähavaintoaineistojen avulla lumipeitteen rakenteen vuosivaihtelua. Analyysit osoittavat, että tilanteessa, jossa porot saavat talviravintonsa vain jäkäliköiltä, vuodenaikainen laidunkierto on käytössä ja diskonttokorko on 0 %, optimaalinen jäkäläbiomassa jäkälälaitumilla on noin 1200 kg/ha. Laidunkierron puuttuminen, jäkäliköiden tuottavuuden lasku ja diskonttokoron nousu pudottavat optimaalista jäkäläbiomassaa (pienimmillään n. 600 kg/ha) ja myös poronhoidon nettotuloja. Porojen laiduntaessa talvella jäkäliköiden ohella luppolaitumia optimaalinen poromäärä kasvaa ja jäkäläbiomassa pienenee, mutta poronhoidon nettotulot pysyvät suurempina kuin pelkästään jäkäliköitä laidunnettaessa. Luppolaitumet myös tasaavat laidunsysteemin epävakautta ja tuottavuuden vuosivaihtelua. Optimitilassa olevilla talvilaitumilla porojen ruokinta ei ole kannattavaa nykyisillä ruokintakustannuksilla (arvioidut kustannukset 0,4€/kg rehua). Ruokintakulujen pudotessa riittävän pieniksi ruokintaan perustuva poronhoito voi muuttua taloudellisesti kannattavaksi, jolloin jäkäliköt ylilaidunnetaan. Myös diskonttokoron nousu sekä elo‐ ja teurasporoille maksetut tuet edistävät porojen ruokintaan siirtymistä. Jos luontaista talviravintoa on vähän, eikä laidunten tilaa pystytä parantamaan, ruokinta on myös kannattavaa. Tällöin poronhoidon nettotulot jäävät kuitenkin pienemmäksi kuin optimitilassa olevilla talvilaitumilla. Sopeutumisprosessin pituus ja poromäärän vähentämistarve kuluneiden jäkäliköiden elvyttämiseksi optimitilaansa osoittautuivat suuremmiksi kuin on arvioitu. Porojen ruokinta sopeutumisprosessin alkuvaiheessa on kannattavaa. Optimaalinen teurastus painottuu vasoihin, vaatimet teurastetaan 9,5 ja hirvaat 5,5 vuoden ikäisinä eli sen jälkeen kun niiden lisääntymisarvo ja paino alkavat pudota. Samalla hirvaita on porokarjassa porojen lisääntymisen kannalta vain vähimmäismäärä, eloporoista 93 % on naaraita ja ikäluokkarakenne sukupuolen osalta tasainen. Parhaassa lisääntymisiässä olevan hirvaan taloudellinen arvo (varjohinta) on korkeampi kuin vastaavan vaatimen arvo. Mallin avulla voitiin arvioida myös jäkälälaidunhehtaarin taloudellista arvoa. Lumi‐ ja kaivuolosuhteista tehdyt analyysit osoittivat, että syvä ja tiivis lumipeite, jääkerrokset sekä myöhäinen lumen sulaminen vaikeuttavat porojen ravinnon saantia ja pudottavat vasatuottoa. SNOWPACK‐mallilla ennustettu lumen tiheys eri talvina korreloi merkitsevästi SYKE:n mittauslinjoilta saatuihin lumen tiheysarvoihin. SNOWPACK‐malli kykeni arvioimaan suhteellisen luotettavasti myös muita poroille vaikeita lumen rakenteellisia ominaisuuksia. Poronhoidon bioekonomisella mallilla tehdyt analyysit selventävät poronhoidossa ja laitumilla tapahtunutta kehitystä Suomessa. Ne auttavat myös hahmottamaan nykytilannetta ja siihen johtaneita syitä. Mallilla voitiin tarkastella myös niitä sopeutumisprosesseja, joita poronhoidossa olisi teh‐tävä, mikäli talvilaidunten tilaa ja porohoidon kannattavuutta haluttaisiin parantaa. Hankkeen tulokset osoittivat myös, että lumen rakenteen vuosivaihtelun ennustaminen SNOWPACK‐mallin avulla tuo hyödyllistä tietoa poronhoidolle.201

CHARTER-hankkeen taustapaperi 1 : Tietoa ja arktisia näkemyksiä ilmasto- ja ympäristölainsäädännön tueksi

Non peer reviewe

Winter condition variability decreases the economic sustainability of reindeer husbandry

Wild and semidomesticated reindeer are one of the key species in Arctic and subarctic areas, and their population dynamics are closely tied to winter conditions. Difficult snow conditions have been found to decrease the calving success and survivability of reindeer, but the economic effects of variation in winter conditions on reindeer husbandry have not been studied. In this study, we combine state-of-the-art economic-ecological modeling with the analysis of annual reindeer management reports from Finland. These contain local knowledge of herding communities. We quantify the occurrence probabilities of different types of winters from annual management reports and analyze the effects of this variation in winter conditions on reindeer husbandry using an age- and sex-structured bioeconomic reindeer-lichen model. Our results show that difficult winters decrease the net revenues of reindeer husbandry. However, they also protect lichen pastures from grazing, thereby increasing future net revenues. Nonetheless, our solutions show that the variability of winter conditions overall decrease the net income of herders compared to constant winter conditions. Low lichen biomass appears to make reindeer management more sensitive to the effects of difficult winter conditions. We also found that it is economically sensible to use supplementary feeding during difficult winters, but the net revenues still decrease compared to average winters because of the high feeding costs. Overall, our analysis suggests that the increasing variability of winter conditions due to climate change will decrease net revenues in reindeer husbandry. This decrease will still occur even if the most extreme effects of climate change do not occur. This study shows that combining a state-of-the-art bioeconomic model and practitioner knowledge can bring compatible insights, ideas, results, and a bottom-up perspective to the discussion.Peer reviewe