Using a spatially precise approach to analyse the occurrence of Usnea longissima in relation to present and past stand structure
To maintain biodiversity in managed forests, long-term trends in forest structure and ecological processes must be understood since these have a decisive influence on the distribution of many forest species, especially epiphytic lichens. To enhance the understanding of the complex occurrence of U...
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| Formato: | Otro |
| Lenguaje: | sueco Inglés |
| Publicado: |
2004
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| Materias: | |
| Acceso en línea: | https://stud.epsilon.slu.se/10829/ |
| _version_ | 1855571758657044480 |
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| author | Josefsson, Torbjörn |
| author_browse | Josefsson, Torbjörn |
| author_facet | Josefsson, Torbjörn |
| author_sort | Josefsson, Torbjörn |
| collection | Epsilon Archive for Student Projects |
| description | To maintain biodiversity in managed forests, long-term trends in forest structure and
ecological processes must be understood since these have a decisive influence on the
distribution of many forest species, especially epiphytic lichens. To enhance the
understanding of the complex occurrence of Usnea longissima Ash. at the stand level, a
spatially precise investigation of present and past stand structure was made in an area in boreal Sweden. Field studies of present occurrence of U. longissima and present forest structure were complemented with dendrochronological analysis and interpretation of different historical sources. Stand structure at present was more or less similar all over the study area. No occurrence of forest fires during the last centuries and absence of forestry operations since the 1930s were most important for the occurrence of U. longissima. However, the distribution of the lichen within the study area could not be explained by present stand structure. Instead, several essential factors affecting the distribution of U. longissima could be related to past stand structure, especially the extent and intensity of previous logging operations and the subsequent stand development. Possibly, pre-industrial forest use and modest selective cuttings may occasionally have contributed to a maintained open forest structure. Evidently, U. longissima appears to be favoured by long-term stability in forest structure, including a somewhat open forest dominated by Picea abies, moderate regrowth of trees and absence of large-scale disturbances. The results indicate that stand history has an important influence on the distribution of epiphytic lichens such as U. longissima and should be considered to achieve a comprehensive management of boreal forests. Furthermore, the use of a spatially precise approach may elucidate many different factors and is practicable for interpreting forest history and long-term changes in habitat conditions. |
| format | Otro |
| id | RepoSLU10829 |
| institution | Swedish University of Agricultural Sciences |
| language | Swedish Inglés |
| publishDate | 2004 |
| publishDateSort | 2004 |
| record_format | eprints |
| spelling | RepoSLU108292017-09-25T10:43:05Z https://stud.epsilon.slu.se/10829/ Using a spatially precise approach to analyse the occurrence of Usnea longissima in relation to present and past stand structure Josefsson, Torbjörn Forestry - General aspects To maintain biodiversity in managed forests, long-term trends in forest structure and ecological processes must be understood since these have a decisive influence on the distribution of many forest species, especially epiphytic lichens. To enhance the understanding of the complex occurrence of Usnea longissima Ash. at the stand level, a spatially precise investigation of present and past stand structure was made in an area in boreal Sweden. Field studies of present occurrence of U. longissima and present forest structure were complemented with dendrochronological analysis and interpretation of different historical sources. Stand structure at present was more or less similar all over the study area. No occurrence of forest fires during the last centuries and absence of forestry operations since the 1930s were most important for the occurrence of U. longissima. However, the distribution of the lichen within the study area could not be explained by present stand structure. Instead, several essential factors affecting the distribution of U. longissima could be related to past stand structure, especially the extent and intensity of previous logging operations and the subsequent stand development. Possibly, pre-industrial forest use and modest selective cuttings may occasionally have contributed to a maintained open forest structure. Evidently, U. longissima appears to be favoured by long-term stability in forest structure, including a somewhat open forest dominated by Picea abies, moderate regrowth of trees and absence of large-scale disturbances. The results indicate that stand history has an important influence on the distribution of epiphytic lichens such as U. longissima and should be considered to achieve a comprehensive management of boreal forests. Furthermore, the use of a spatially precise approach may elucidate many different factors and is practicable for interpreting forest history and long-term changes in habitat conditions. En förutsättning för att bedriva ett effektivt skogsbruk samtidigt som en hög biodiversitet bibehålls är fördjupad kunskap om långsiktiga förändringar av skogsstrukturen och ekologiska processer. Utbredningen av många skogslevande arter, i synnerhet epifytiska lavar, styrs till stor del av dessa faktorer. Syftet med denna studie var att öka kunskapen kring långskäggslavens (Usnea longissima Ash.) komplicerade utbredning på beståndsnivå i norra Sverige. Förutom en fältstudie av långskäggsförekomst och nuvarande beståndsstruktur användes två olika skogshistoriska metoder, närmare bestämt dendrokronologi och tolkning av olika historiska dokument. Studieområdet hade inte påverkats av skogsbruk sedan 1930- talet och några tecken på skogsbrand under de senaste seklen återfanns ej. Dessa faktorer är avgörande för förekomsten av U. longissima i studieområdet. När det gäller utbredningen av U. longissima i området kunde denna relateras till beståndshistoriken, framför allt omfattningen av tidigare huggningar samt efterföljande beståndsutveckling. Möjligen kan förindustriellt agrart bruk av skogen samt småskalig plockhuggning i vissa fall ha bidragit till en bibehållen öppen skogsstruktur. Långskäggslaven tycks således gynnas av en beständig och något öppen skogsstruktur med dominans av gran (Picea abies L. Karst), långsam tillväxt samt frånvaro av storskaliga störningar. Resultat visar att beståndshistorik har stor inverkan på förekomsten av epifytiska lavar såsom långskäggslav och bör därför beaktas vid skötseln av våra boreala skogar. Djupgående studier på små områden hjälper till att belysa många olika faktorer samt är användbara för tolkning av skogshistoria och långsiktiga förändringar av olika habitat. 2004-04-22 Other NonPeerReviewed application/pdf sv https://stud.epsilon.slu.se/10829/1/josefsson_t_170925.pdf Josefsson, Torbjörn, 2004. Using a spatially precise approach to analyse the occurrence of Usnea longissima in relation to present and past stand structure : a case study in boreal Scandinavia. UNSPECIFIED, Umeå. Umeå: (S) > Dept. of Forest Ecology and Management <https://stud.epsilon.slu.se/view/divisions/OID-241.html> urn:nbn:se:slu:epsilon-s-7135 eng |
| spellingShingle | Forestry - General aspects Josefsson, Torbjörn Using a spatially precise approach to analyse the occurrence of Usnea longissima in relation to present and past stand structure |
| title | Using a spatially precise approach to analyse the occurrence of Usnea longissima in relation to present and past stand structure |
| title_full | Using a spatially precise approach to analyse the occurrence of Usnea longissima in relation to present and past stand structure |
| title_fullStr | Using a spatially precise approach to analyse the occurrence of Usnea longissima in relation to present and past stand structure |
| title_full_unstemmed | Using a spatially precise approach to analyse the occurrence of Usnea longissima in relation to present and past stand structure |
| title_short | Using a spatially precise approach to analyse the occurrence of Usnea longissima in relation to present and past stand structure |
| title_sort | using a spatially precise approach to analyse the occurrence of usnea longissima in relation to present and past stand structure |
| topic | Forestry - General aspects |
| url | https://stud.epsilon.slu.se/10829/ https://stud.epsilon.slu.se/10829/ |