Vedboende biller i de kommunale skove Biodiversitet i
Vedboende biller i de kommunale skove Biodiversitet i skov – fokus på arter og processer Hans Peter Ravn hpr@ign. ku. dk Sektion for Skov, Natur og Biomasse ”Kommunale biller” versus andre biller Hvorfor? Hvad er vi oppe imod? Populære biller/upopulære biller! Biller som organismegruppe – De mest diverse! De sjældneste – biller knyttet til gl skov Kan det lade sig gøre i kommunale skove ? ! AHA-metoden Dødt ved på mange måder – kun fantasiien sætter grænser!
Coleoptera – den formrigeste organismegruppe! Valsgaard 10. juni 2014
”Kommunale biller” versus andre biller Kommunerne forvalter arealer, der repræsenterer meget forskelligartede naturtyper – ud over skovene: enge, kær, søer, åer, overdrev, vejrabatter, strandoverdrev, klitter, heder –og kulturarealer med mere eller mindre grønt islæt: idrætsanlæg, fælleder, bygnigsomgivelser Der indgår mangesidige hensyn i kommunal naturforvaltning: Rekreative interesser, sport og idræt, kulturhistoriske værdier, lokalt særpræg, biodiversitets hensyn og økonomiske hensyn Valsgaard 10. juni 2014
Hvorfor biodiversitet? • Vi har forpligtet os [Rio 1992, Johannesburg 2004, Nagyoa 2010 og EU’s biodiversitetsstrategi 2011 -20] • Økonomiske fordele ”The befits that human population derive, directly or indirectly, from ecosystem functions” (Bolund and Hunhammer 1999) Provisioning services – fx føde og ferskvand Regulating services – fx lokal klima, luftkvalitet, kulstofbinding, regnvandstilbageholdelse og bestøvning Habitat or supporting services – fx levesteder for planter og dyr Cultural services – fx rekreation, mental helse, æstetiske oplevelser (The Economics of Ecosystems and Biodiversity, 2011) Valsgaard 10. juni 2014
Efficient utilisation of all ressources => diversity Biomass per areal: Seeds: Lepidoptera, Coleoptera, Hymenoptera Diptera Sapfeeders. Hemiptera (aphids, feaf-hoppers, plant bugs) Wood-living: Lepidoptera, Coleoptera Hymenoptera Buds and shoot tips: Lepidoptera Coleoptera Leaf eaters: Lepidoptera Coleoptera, Hymenoptera, Diptera, Orthoptera Bark: Coleoptera, Hemiptera Roots: Coleoptera, Hemiptera Birds: 1 -2 kg/ha Large mammals: 2 kg/ha Small mammals: 5 kg/ha Canopy insects: 100 kg/ha Soil fauna: 1 -2 t/ha The trees: 3 -400 t/ha
Danish red list species distributed on species and forest habitat type RE IN ALL, FOREST Forest edges Old forest Broadleaved Conifers Swamp forest Untouched forest Wood material CR VU NT
Forest & Landscape Red list conclusion 2010 ”The largest group og endangered species - every five – are forest species. From this group every third species is either disappeared or endangered” Dias 8
Saproxylic insects (dead wood dependant) Coleoptera – beetles In Sweden: 4. 650 – saproxylics: 1. 075 Hymenoptera – wasps, ants and bees In Sweden: 8. 000 – saproxylics: >1. 500 Diptera – flies, midges and craneflies In Sweden: 7. 000 – saproxylics: ca 1. 000 (from Sörensen 2008)
Tree species, native herbivore species Denmark, beetle species Oak conif. Salix Betula Fagus Populus Cherry Ash Elm Tilia Acer Carpinus Sorbus Horsechestnut
Forest & Landscape Tree species, native herbivore insect species Sweden Salix Betula Oak Prunus spin. Populus Cratategus Pinus Malus Alnus Picea Ulmus Fagus Coryllus Sorbus Tilia Fraxinus Carpinus Dias 12 GB
Tree species selection – the most popular Adminitrator choise: Tilia Sorbus Quercus Fraxinus Acer Platanus Fagus Carpinus Bird-Cherry Ulmus Populus Others Horse-Chestnut Betula Conifers Salix (Thomas Randrup) Coleopterists choise: Quercus Fagus Ulmus Sorbus Populus Betulus Fraxinus Salix Pinus Tilia Bird-Cherry Carpinus Acer Picea Horse-chestnut Platanus (Palle Jørum) Macro lepidoptera, specific tree choise: Salix – 87 Betula – 60 Populus – 40 Fagus – 34 Quercus – 22 Alnus – 22 Picea – 16 Pinus - 15 Ulmus – 11 Tilia – 10 Fraxinus – 8 Larix - 4 Acer – 3 Bird-cherry – 3 Horse-Chestnut – 2 Sorbus – 4 Acer pseupl. – 1 (Per Stadel Nielsen)
13 tree species estimated relative importance for four groups of organisms Tree species mychorrhiza polypore fungi insects nesting birds Betula Quercus pe Fagus silv Salix sp Alnus sp. Larix sp. Pinus syl. Ulmus gla. Pseudotsu Picea abies Fraxinus Abies sp Acer sp (Flemming Rune, mycologist)
Drymatter insects – microgram/squaremeter leaf Birds food ressource on 8 common tree species, Strødam Mobile sessile Sessile -vers. mobile species Betula pub. Quercus pend. Alnus r. Sambucus Fraxinus Salix Picea abies Fagus sylv. (Karsten Laursen, pers. comm. )
Keep surface natural
Old traditional growing practises may increas diversity • Coppice (Stævningsdrift) • Willow production, bocage
Important messages • Save continuity in tree species selection • Save continuity in in age distribution and degree of degradation – both standing and horizontal dead wood • Save stumps (low and high) both broadleaved and conifers • Transitions between closed stands and open land are particular species rich and should have particular attention
Brand - betydningen Fire creates a quite particular flora and fauna
Fauna succession in deadwood The first short fase (12 years) is dominated by barkliving insects: barkbeetles, weevils and longhorned beetles. Only few red listed species are among these
Fauna succession in deadwood 2 nd fase is longer dominated by species that lives under the bark and in the sapwood. Fungi abundant. Bark loosen and begin to fall off. More species feeds on the central wood. Some redlisted species.
Fauna succession in deadwood 3 rd fase. Several decenniums. Bark gone. Many rare and red listed species. Click-beetles, fungivores and predators
Fauna succession in deadwood 4 th fase. Shelter more than food. Ground living insects, millipedes, slugs and snails
Forest & Landscape Dias 26
Forest & Landscape Veteran tree An ‘ideal’ veteran tree for wildlife. Dias 27
Forest & Landscape Dias
Valsgaard 10. juni 2014
Forest & Landscape Mikael Sörensens AHA-method A method for identification of single tree conservation priority as a function of teir probablity of keeping redlisted saproxylic insect species Stem with cavity: A- large with mould, B- commencing cavity Branch with cavity: A – large with mould or water, B - small Mucorrhea: A> Epiphytic fungi: 10 cm long A: several B< 10 cm B: a few Stem with loose bark: A: > 3 dm 2 B: < 3 dm 2 A: Decaying B: Giant tree > high stump >40 1 m BHD (>314 cm BHD cm periphery) AHA-Class Class Class I: two A - Highest conservation priority (~100%) II: one A or four B -High conservation priority (~50%) III: two B - Of some conservation priority (~10%) IV: one or no B- Low priority (~0%) R: Resource tree - Older, healthy, undamaged trees (Mikael Sörensen 2008) Dias 30
Valsgaard 10. juni 2014
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