Älgens barkgnag på granstammar : omfattning med avseende på geografisk utbredning, skadad volym och ekonomiska konsekvenser
In three areas in the province of Småland studies has been done to investigate how big damage the moose may do to P. abies. An inquiry examination and two different types of surveys were done to find out how big area, which volume and which financial consequences the moose debarking has had on th...
| Main Author: | |
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| Format: | L3 |
| Language: | Swedish Inglés |
| Published: |
SLU/Southern Swedish Forest Research Centre
2008
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| Subjects: |
| _version_ | 1855571867492941824 |
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| author | Steffen, Helena |
| author_browse | Steffen, Helena |
| author_facet | Steffen, Helena |
| author_sort | Steffen, Helena |
| collection | Epsilon Archive for Student Projects |
| description | In three areas in the province of Småland studies has been done to investigate how big
damage the moose may do to P. abies. An inquiry examination and two different types of
surveys were done to find out how big area, which volume and which financial consequences
the moose debarking has had on the forest.
When the volume was calculated the rot spreading was included. The area that was damaged
was stipulated with the answers from the inquiry examination. 59 % of the asked forest
owners answered the inquiry. The area that the study included was on 22 900 ha and the result
showed that there were moose damages on 162 ha.
When the whole trees were included the damaged volume was 16 m3sk/ha which is 8, 6 %.
On the damaged 162 ha totally 2 570 m3sk was damaged, 385 m3sk had technical damages
and 616 m3sk had damages which included decayed wood.
When the financial calculation was made only the first 3 meters was included, this because
the assumption was done that the decaying wood never extended above 3 meters. The
damaged volume counted on 3 meters was 4, 3 m3sk/ha, totally 692 m3sk. If a comparison is
made between timber prices and pulpwood prices the difference is 67 000 kr, all areas
included. |
| format | L3 |
| id | RepoSLU11408 |
| institution | Swedish University of Agricultural Sciences |
| language | swe Inglés |
| publishDate | 2008 |
| publishDateSort | 2008 |
| publisher | SLU/Southern Swedish Forest Research Centre |
| publisherStr | SLU/Southern Swedish Forest Research Centre |
| record_format | eprints |
| spelling | RepoSLU114082017-10-06T07:42:28Z Älgens barkgnag på granstammar : omfattning med avseende på geografisk utbredning, skadad volym och ekonomiska konsekvenser Bark stripping by moose on Norway spruce stems : the geographic distribution, damaged volume and economic consequences Steffen, Helena älg barkgnag gran In three areas in the province of Småland studies has been done to investigate how big damage the moose may do to P. abies. An inquiry examination and two different types of surveys were done to find out how big area, which volume and which financial consequences the moose debarking has had on the forest. When the volume was calculated the rot spreading was included. The area that was damaged was stipulated with the answers from the inquiry examination. 59 % of the asked forest owners answered the inquiry. The area that the study included was on 22 900 ha and the result showed that there were moose damages on 162 ha. When the whole trees were included the damaged volume was 16 m3sk/ha which is 8, 6 %. On the damaged 162 ha totally 2 570 m3sk was damaged, 385 m3sk had technical damages and 616 m3sk had damages which included decayed wood. When the financial calculation was made only the first 3 meters was included, this because the assumption was done that the decaying wood never extended above 3 meters. The damaged volume counted on 3 meters was 4, 3 m3sk/ha, totally 692 m3sk. If a comparison is made between timber prices and pulpwood prices the difference is 67 000 kr, all areas included. Inventeringar har genomförts i tre socknar i Småland för att ta reda på omfattningen av älgens barkgnag på gran (Picea abies, L. Karst). En enkätundersökning samt en cirkel- och linjeinventering utfördes för att kartlägga den geografiska omfattningen, skadad volym samt ekonomiska konsekvenser av älgarnas barkgnag. Vid uträkningen av mängden skadad volym togs hänsyn till en successiv spridning av röta som antogs infektera träden. Den geografiska omfattningen av skadorna fastställdes med hjälp av markägarnas svar på enkäten, svarsfrekvensen uppgick till drygt 59 %. Den totala fastighetsarealen som enkäten berörde var knappt 22 900 ha och det visade sig att det fanns skador på 162 ha skogsmark. På dessa 162 ha där skador har observerats visade det sig att 8,6 % av granarna var skadade genom älgens barkgnag, detta motsvarar ca 16 m3 sk/ha dvs. totalt ca 2 570 m3 sk . När volymen endast inkluderar den del av träden som begränsas av de tekniska skadornas övre höjd blir den totala mängden skadad volym 385 m3 sk. När även den förmodade rötspridningen i höjdled inkluderas uppgår den totala skadade volymen till 616 m3 sk. De ekonomiska beräkningarna baserades på första stockens volymer d.v.s. de nedersta tre metrarna, detta eftersom antagandet gjordes att rötspridningen aldrig nådde över tre meter. Vid detta antagande uppgick den skadade volymen till 4,3 m3 sk/ha totalt 692 m3 sk. Vid en nerklassning från timmer till massaved, av den förmodat rötskadade volymen, blev skillnaden 67 000 kr, samtliga bestånd inkluderade. SLU/Southern Swedish Forest Research Centre 2008 L3 swe eng https://stud.epsilon.slu.se/11408/ |
| spellingShingle | älg barkgnag gran Steffen, Helena Älgens barkgnag på granstammar : omfattning med avseende på geografisk utbredning, skadad volym och ekonomiska konsekvenser |
| title | Älgens barkgnag på granstammar : omfattning med avseende på geografisk utbredning, skadad volym och ekonomiska konsekvenser |
| title_full | Älgens barkgnag på granstammar : omfattning med avseende på geografisk utbredning, skadad volym och ekonomiska konsekvenser |
| title_fullStr | Älgens barkgnag på granstammar : omfattning med avseende på geografisk utbredning, skadad volym och ekonomiska konsekvenser |
| title_full_unstemmed | Älgens barkgnag på granstammar : omfattning med avseende på geografisk utbredning, skadad volym och ekonomiska konsekvenser |
| title_short | Älgens barkgnag på granstammar : omfattning med avseende på geografisk utbredning, skadad volym och ekonomiska konsekvenser |
| title_sort | älgens barkgnag på granstammar : omfattning med avseende på geografisk utbredning, skadad volym och ekonomiska konsekvenser |
| topic | älg barkgnag gran |