Bengt-Gunnar Jonsson

Šioje politikos gairių santraukoje apibendrinami moksliniai duomenys apie Šiaurės Europos (borea¬linių ir hemiborealinių) senųjų miškų (sin. sengirių) ekologiją, struktūrą ir natūralią raidą bei pateikiamos aiškios, praktiškai pritaikomos ir mokslu pagrįstos rekomendacijos, kaip šiame regione taikyti Europos Komisijos sengirių rodiklius. Pagal Europos Komisijos gaires miško medynas gali būti priskirtas sengirei, jei jis atitinka visus tris pagrindinius rodiklius (2–4 rekomendacijos) ir bent du papildomus rodiklius (5–8 rekomendacijos). Ši politikos gairių santrauka parengta remiantis recenzuota moksline publikacija ir yra skirta politikos formuotojams, viešojo administravimo institucijoms bei kitoms suinteresuotosioms šalims, ieškančioms objektyvių ir patikimų rekomendacijų sengirėms nustatyti visoje Šiaurės Europoje.

Šajā politiskajā pārskatā ir apkopotas zinātniskas atziņas par Ziemeļeiropas (boreālo un hemiboreālo) veco mežu (OGF – old-growth forest) ekoloģiju, struktūru un dabisko attīstības dinamiku, kā arī sniegti skaidri, praktiski un zinātniski pamatoti ieteikumi Eiropas Komisijas noteikto veco mežu indikatoru piemērošanu šajā reģionā. Saskaņā ar Komisijas vadlīnijām mežaudzes ir kvalificējamas kā veci meži, ja tās atbilst visu trīs galveno indikatoru kritērijiem (2.–4. ieteikums), kā arī vismaz diviem papildu kritērijiem (5.–8. ieteikums). Šis politikas veidošanai orientētais ziņojums ir balstīts uz recenzētu zinātnisku publikāciju un ir sagatavots politikas veidotājiem, valsts iestādēm un citām ieinteresētajām pusēm, kurām nepieciešamas objektīvas un uzticamas vadlīnijas veco mežu identificēšanai visā Ziemeļeiropā.

Väljaandes antakse ülevaade Põhja-Euroopa (boreaalsete ja hemiboreaalsete) loodusmetsade (ingl. oldgrowth forest) ökoloogiast, struktuurist ja looduslikust dünaamikast ning tuletatakse sellest selged, praktilised ja teaduspõhised soovitused, kuidas rakendada Euroopa Komisjoni loodusmetsa indikaatoreid Põhja-Euroopa tingimustes. Komisjoni juhiste kohaselt saab puistut käsitada loodusmetsana siis, kui selles on tuvastatud kõik kolm põhiindikaatorit (soovitused 2–4) ning vähemalt kaks täiendavat indikaatorit (5–8). Ülevaade põhineb eelretsenseeritud teaduspublikatsioonil ning on mõeldud poliitikakujundajatele, ametiasutustele ja teistele huvirühmadele, kes vajavad objektiivseid ja usaldusväärseid juhiseid loodusmetsade määratlemiseks Põhja-Euroopas.

Denna policy brief sammanställer vetenskaplig evidens om ekologin, strukturen och den naturliga dynamiken i nordeuropeiska (boreala och hemiboreala) urskogslika (OGF – Old Growth Forest) och ger tydliga, operativa, vetenskapsbaserade rekommendationer för implementering av EU-kommissionens indikatorer i denna region. Enligt kommissionens riktlinjer kvalificerar skogsbestånd som urskogslika om de uppfyller kriterierna för alla tre huvudindikatorerna (rekommendationerna 2–4) samt minst två kompletterande (5–8). Denna policy brief är baserad på en sakkunniggranskad vetenskaplig publikation och är skriven för beslutsfattare, offentliga myndigheter och intressenter som söker objektiv och tillförlitlig vägledning för att identifiera urskogslika skogar i hela norra Europa. (Notera att i texten nedan används ”urskog” som begrepp för att språkligt underlätta läsningen men avser ”urskogslika skogar” (OGF) enligt EU-kommissionens definition.)

This policy brief synthesizes scientific evidence on the ecology, structure, and natural dynamics of North-European (boreal and hemiboreal) old-growth forests (OGF), and provides clear, operational, science-based recommendations for implementing the European Commission’s OGF indicators in this region. According to the Commission guidelines, forest stands qualify as OGF if they fulfil the criteria of all three main indicators (recommendations 2-4) plus at least two complementary ones (5-8). This policy brief is based on peer-reviewed scientific publication1, and written for policymakers, public authorities, and stakeholders seeking objective, reliable guidance for identifying old-growth forests throughout Northern Europe.

Tämä julkaisu kokoaa yhteen tieteellistä näyttöä Pohjois-Euroopan (boreaalisten ja hemiboreaalisten) metsien ekologiasta, rakenteesta ja luonnollisesta kehityksestä ja tarjoaa selkeitä, käytännönläheisiä ja tieteeseen perustuvia suosituksia Euroopan komission vanhojen metsien indikaattoreiden soveltamiseksi tällä alueella. Komission ohjeen mukaisesti metsäkuvio on vanha metsä, jos kaikkien kolmen pääindikaattorin (suositukset 2–4) sekä vähintään kahden täydentävän indikaattorin (5–8) kriteerit täyttyvät. Julkaisu perustuu vertaisarvioituun katsausartikkeliin1 ja on tarkoitettu päätöksentekijöille, viranomaisille ja sidosryhmille. Se tarjoaa objektiivisia, tieteeseen perustuvia ohjeita vanhojen metsien tunnistamiseksi koko Pohjois-Euroopan alueella.

Primary and old-growth forests are globally valued for their biodiversity, ecosystem services, and cultural significance. The EU biodiversity strategy and EU forest strategy for 2030 require strict protection of remaining primary and old-growth forests, yet they cover only about 3% of EU forest area and remain highly threatened. The European Commission’s guidelines define old-growth forests using three main indicators—native tree species, deadwood, and large/old trees—supported by four complementary indicators. Implementing these indicators for boreal and hemiboreal old-growth forests in Europe currently lack science-based operational criteria that meet EU legal standards. We provide recommendations for implementing European Commission’s indicators with science-based criteria to minimize misclassification and ensure cost-effective conservation. Key criteria include native species dominance, ≥ 5% deadwood of the total wood volume, and ≥ 20 large/old trees per hectare. Additional guidance is offered for regeneration patterns, structural complexity, microhabitats, and indicator species, emphasizing that all indicators should be applied collectively.

Introduction: Tree planting for ecosystem restoration often occurs on disturbed, degraded, or former agricultural sites, where seedlings face harsh conditions like sun exposure, drought, wind, frost, and browsing, which can lead to poor performance. To improve survival and growth, nurse structures such as nurse plants, plant residues, or artificial shelters may be used to buffer environmental stress. Objectives: We aimed to assess how different nurse structures influence the performance of restoration plantings and how this effect varies with climate and environmental stressors, nurse structure type, plantation age, and tree species traits. Methods: Using descriptive statistics and meta‐analyses, we systematically reviewed 82 studies from temperate and boreal forests addressing effects of nurse structures on the performance of planted trees. Results: Nurse structures improve the performance of planted seedlings or saplings, particularly by enhancing survival and height growth. However, their effects on diameter growth and plant water status tend to be negative. The effects are consistent across tree species types but are stronger in temperate and continental climates, in younger plantations, and when using artificial shelters rather than nurse plants. Nurse structures are most effective at mitigating drought, frost, and browsing, while evidence for impacts on competition or wind is inconclusive. Conclusions: Survival and growth of planted seedlings are improved through nurse structures. However, their effectiveness is context‐dependent, so site‐specific conditions should be considered when applying them for restoration purposes.

Primary and old-growth forests are globally valued for their biodiversity, ecosystem services, and cultural significance. The EU Biodiversity Strategy and EU Forest Strategy for 2030 require strict protection of remaining primary and old-growth forests, yet they cover only about 3% of EU forest area and remain highly threatened. The European Commission’s guidelines define old-growth forests using three main indicators—native tree species, deadwood, and large/old trees—supported by five complementary indicators. Implementing these indicators for boreal and hemiboreal old-growth forests in northern Europe currently lack science-based operational criteria that meet EU legal standards. We provide recommendations for implementing European Commission’s indicators with science-based operational criteria and thresholds to minimize misclassification and ensure cost-effective conservation. Key thresholds include native species dominance, ≥5% deadwood of the total wood volume, and ≥20 large/old trees per hectare. Additional guidance is offered for regeneration patterns, structural complexity, microhabitats, and indicator species, emphasizing that all indicators should be applied collectively.

Harvesting naturally dynamic forests causes losses of habitat quality and functional connectivity. Focusing on Sweden as a case study of high-yield rotation forestry, we provide analyses supporting spatial prioritisation of protection, management and restoration of representative functional forest habitat networks. Habitat suitability index modelling of focal bird species was used to analyse how forest naturalness, habitat patch size and functional connectivity affect representative forest habitat networks in Sweden’s five ecoregions. Habitat modelling for the least demanding bird species showed that of the mountain ecoregion 57–77% was functional, but in the other three boreal ecoregions only 8–9% were functional. For nemoral forests, the proportions of functional habitat networks were < 3%. More demanding species have even less functional habitat. We highlight the importance of the mountain ecoregion for forest biodiversity conservation, and the urgent need for landscape planning of protection, conservation management and nature restoration in Sweden.