Inventering och klassificering av kvarlämnad virkesvolym vid slutavverkning
This final thesis is performed on commission of Hargs Bruk Ltd. Hargs Bruk manages one of Sweden's largest privately owned forests. A main part of the managed forest is situated in Roslagen in eastern Uppland. Since 1934 felling calculations have been performed within the estate every tenth year. A...
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| Formato: | Otro |
| Lenguaje: | sueco sueco |
| Publicado: |
2007
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| Acceso en línea: | https://stud.epsilon.slu.se/11966/ |
| _version_ | 1855571974586105856 |
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| author | Stangebye, Jan |
| author_browse | Stangebye, Jan |
| author_facet | Stangebye, Jan |
| author_sort | Stangebye, Jan |
| collection | Epsilon Archive for Student Projects |
| description | This final thesis is performed on commission of Hargs Bruk Ltd. Hargs Bruk manages one of Sweden's largest privately owned forests. A main part of the managed forest is situated in Roslagen in eastern Uppland. Since 1934 felling calculations have been performed within the estate every tenth year. According to the felling calculation from 2001 the share of standing volume broad-leaved trees should be at an average level of 18 %. Also according to this calculation the percentage by volume of broad-leaved trees in the thinning stands should be at a level of 21.4 % and in the final cut stands the percent by volume should be 14.6 %. These volumes are supposed to be brought in from an area of 18 322 hectares including small areas of waste land and stands with environmental restrictions at final cut operations. The reduction of the productive area is in total 1 354 hectares, about 7.4 %. From the total percent by volume of 14.6 % broad-leaved trees the company expects that, in these reduced areas, a level of 2.5 percentage units broad-leaved trees are situated. The expected result of the share of hardwood delivered is for that reason about 12 percent by volume. During the latest four years, the result of broad-leaved trees at final cut operations has been at a level of slightly 10% by volume. According to the calculations in this study the amount of hardwood that has been cut and delivered is 6 301 m3sk, in other words 8.8% by volume, during the years 2003 and 2004. According to this, the company wishes to investigate if the expected share of broad-leaved trees is left behind after final cut operations or if the final cut stands before final cut operations did not contain a share of broad-leaved trees to the extent that calculations show.
A major part of this study was carried out as a field inventory of final cut areas within Harg forestry region. The survey has been conducted in final felling areas and the total number of investigated objects is 28. The felling area was registered with GPS. By following edges of felling objects the cultivated area could be determined. In order to be able to answer the question if there was 14.6 percent by volume of broad-leaved trees before the final cut operation, the measured volume was added to the delivered volume. By that means a decent estimation of the former existing volume with the shares of broad-leaved trees before final cut operation could be made. The survey shows that the standing volume at final cut objects during the year of 2003 and 2004 contained 11.4 percent by volume of broad-leaved trees, not the expected 14.6 percent by volume. Furthermore it was found that the contractor left 31 percent by volume of the accessible broad-leaved trees behind and due to this, that the share of delivered hardwood from these stands was lowered. The reason for this could be that the production trees, according to this study, contained a greater volume per tree. By making comparisons with younger age classes one can probably expect to receive a greater share of hardwood in the future. |
| format | Otro |
| id | RepoSLU11966 |
| institution | Swedish University of Agricultural Sciences |
| language | Swedish swe |
| publishDate | 2007 |
| publishDateSort | 2007 |
| record_format | eprints |
| spelling | RepoSLU119662017-11-15T09:50:26Z https://stud.epsilon.slu.se/11966/ Inventering och klassificering av kvarlämnad virkesvolym vid slutavverkning Stangebye, Jan Forestry production This final thesis is performed on commission of Hargs Bruk Ltd. Hargs Bruk manages one of Sweden's largest privately owned forests. A main part of the managed forest is situated in Roslagen in eastern Uppland. Since 1934 felling calculations have been performed within the estate every tenth year. According to the felling calculation from 2001 the share of standing volume broad-leaved trees should be at an average level of 18 %. Also according to this calculation the percentage by volume of broad-leaved trees in the thinning stands should be at a level of 21.4 % and in the final cut stands the percent by volume should be 14.6 %. These volumes are supposed to be brought in from an area of 18 322 hectares including small areas of waste land and stands with environmental restrictions at final cut operations. The reduction of the productive area is in total 1 354 hectares, about 7.4 %. From the total percent by volume of 14.6 % broad-leaved trees the company expects that, in these reduced areas, a level of 2.5 percentage units broad-leaved trees are situated. The expected result of the share of hardwood delivered is for that reason about 12 percent by volume. During the latest four years, the result of broad-leaved trees at final cut operations has been at a level of slightly 10% by volume. According to the calculations in this study the amount of hardwood that has been cut and delivered is 6 301 m3sk, in other words 8.8% by volume, during the years 2003 and 2004. According to this, the company wishes to investigate if the expected share of broad-leaved trees is left behind after final cut operations or if the final cut stands before final cut operations did not contain a share of broad-leaved trees to the extent that calculations show. A major part of this study was carried out as a field inventory of final cut areas within Harg forestry region. The survey has been conducted in final felling areas and the total number of investigated objects is 28. The felling area was registered with GPS. By following edges of felling objects the cultivated area could be determined. In order to be able to answer the question if there was 14.6 percent by volume of broad-leaved trees before the final cut operation, the measured volume was added to the delivered volume. By that means a decent estimation of the former existing volume with the shares of broad-leaved trees before final cut operation could be made. The survey shows that the standing volume at final cut objects during the year of 2003 and 2004 contained 11.4 percent by volume of broad-leaved trees, not the expected 14.6 percent by volume. Furthermore it was found that the contractor left 31 percent by volume of the accessible broad-leaved trees behind and due to this, that the share of delivered hardwood from these stands was lowered. The reason for this could be that the production trees, according to this study, contained a greater volume per tree. By making comparisons with younger age classes one can probably expect to receive a greater share of hardwood in the future. Det här examensarbetet är utfört på uppdrag av Hargs Bruk AB. Godset förvaltar en av Sveriges största privata skogar. Merparten av skogen som de förvaltar är belägen i Roslagen i östra Uppland. Sedan 1934 har avverkningsberäkningar utförts för skogen, vilka har förnyats vart tionde år. Enligt den senaste avverkningsberäkningen från 2001 är procentandelen lövvirke i virkesförrådet ungefär 18 %. Enligt denna beräkning ska volymandelen lövvirke i gallringsbestånden vara 21,4 % och i slutavverkningsbestånden ska volymandelen löv som slutavverkas vara 14,6 % utav den totala virkesfångsten. Dessa volymer ska bärgas från en areal om 18 322 hektar med små impediment och områden med avverkningsrestriktioner. Arealavdragen uppgår till 1 354 hektar, d.v.s. 7,4 %. På dessa ytor räknar man med att det finns ungefär 2,5 procentenheter löv av de totala 14,6 %. Den förväntade volymandelen lövvirke vid slutavverkning är därför ca 12 %. De senaste fyra åren har utfallet löv vid slutavverkning dock legat på en nivå av knappa 10 %. Enligt utförda beräkningar var andelen lövvirke som levererades, under åren 2003 och 2004, 6 301 m3sk d.v.s. 8,8 %. Med detta som bakgrund önskar företaget undersöka frågan om det förväntade lövvirket finns kvarlämnat efter avverkning eller om slutavverkningsbestånden före avverkning inte innehållit lövvirke i den omfattning som beräkningar visat. En stor del av examensarbetet har genomförts som inventering i fält på slutavverkade trakter. Det totala antalet trakter som inventerats och registrerats i studien uppgår till 28. Inom varje trakt har den brukade arealen mätts upp med hjälp av GPS. Genom att följa hyggeskanten runt hela hygget kunde den brukade arealen bestämmas. För att kunna svara på frågan om det fanns en andel om 14,6 % lövvirke innan avverkningen adderades uppmätt volym i fält med levererad volym. Därigenom erhölls en grov uppfattning av beståndets virkesförråd med fördelning på trädslag före avverkning. Studien visar att virkesförrådet hos slutavverkade objekt åren 2003 och 2004 höll en lövvirkesandel på 11,4 % och inte de prognostiserade 14,6%. Vidare konstaterades att maskinlagen lämnade kvar 31 % av tillgängligt lövvirke, vilket ytterligare sänkte andelen levererat lövvirke från dessa bestånd. Anledningen till detta kan vara att produktionsträden enligt denna undersökning visat sig hålla en större volym per träd. Vid jämförelser med de yngre åldersklasserna kan man troligen förvänta sig erhålla en större lövvirkesandel i framtiden. 2007-03-12 Other NonPeerReviewed application/pdf sv https://stud.epsilon.slu.se/11966/1/stangebye_j_171115.pdf Stangebye, Jan, 2007. Inventering och klassificering av kvarlämnad virkesvolym vid slutavverkning. UNSPECIFIED, Uppsala. Uppsala: (S) > Dept. of Forest Products <https://stud.epsilon.slu.se/view/divisions/OID-231.html> urn:nbn:se:slu:epsilon-s-8812 swe |
| spellingShingle | Forestry production Stangebye, Jan Inventering och klassificering av kvarlämnad virkesvolym vid slutavverkning |
| title | Inventering och klassificering av kvarlämnad virkesvolym vid slutavverkning |
| title_full | Inventering och klassificering av kvarlämnad virkesvolym vid slutavverkning |
| title_fullStr | Inventering och klassificering av kvarlämnad virkesvolym vid slutavverkning |
| title_full_unstemmed | Inventering och klassificering av kvarlämnad virkesvolym vid slutavverkning |
| title_short | Inventering och klassificering av kvarlämnad virkesvolym vid slutavverkning |
| title_sort | inventering och klassificering av kvarlämnad virkesvolym vid slutavverkning |
| topic | Forestry production |
| url | https://stud.epsilon.slu.se/11966/ https://stud.epsilon.slu.se/11966/ |