Simulation of rattan harvests in Indonesia : different harvesting pressures and the resulting patterns
The objectives of this research were to determine whether the natural rattan resources in Sulawesi, Indonesia can cope with the strongly increased harvesting pressure that has occurred over the last centuries. I was furthermore looking for patterns in the rattan population dynamics that might give a...
| Autor principal: | |
|---|---|
| Formato: | H2 |
| Lenguaje: | Inglés sueco alemán |
| Publicado: |
SLU/Southern Swedish Forest Research Centre
2013
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| Materias: |
| _version_ | 1855570860442648576 |
|---|---|
| author | Hess, Bastian |
| author_browse | Hess, Bastian |
| author_facet | Hess, Bastian |
| author_sort | Hess, Bastian |
| collection | Epsilon Archive for Student Projects |
| description | The objectives of this research were to determine whether the natural rattan resources in Sulawesi, Indonesia can cope with the strongly increased harvesting pressure that has occurred over the last centuries. I was furthermore looking for patterns in the rattan population dynamics that might give a hint on how the harvesting system could be improved to ensure a maximum sustainable yield. To
answer these questions, I developed an individual-based model to analyse the dynamics of rattan growth in connection with rattan harvests by locals to identify sustainable levels of rattan harvests around villages in Sulawesi, Indonesia. Scenarios with different harvesting intensities were run to compare the change in harvest amount. For a given harvesting pressure, scenarios with a high number of harvesters and a low harvesting frequency had the same effect as scenarios with high harvesting frequencies and a low number of harvesters. Scenarios with a high harvesting pressure led to a rapid decline of the harvested rattan amounts. Simulations showed that a maximum sustainable yield can be obtained as long as a harvesting pressure of 1.13 harvesting actions per month in an
area of 7.07 km2 was not exceeded. Comparing the current harvesting situation with the different scenarios from the model, a long-term sustainable harvest seems unlikely, especially when considering that there is an increasing worldwide rattan demand, for which specialized rattanharvesting groups intensify their harvesting actions. To avoid further overexploitation of Indonesia’s
rattan resources there is a need to manage rattan harvests. |
| format | H2 |
| id | RepoSLU5528 |
| institution | Swedish University of Agricultural Sciences |
| language | Inglés swe ger |
| publishDate | 2013 |
| publishDateSort | 2013 |
| publisher | SLU/Southern Swedish Forest Research Centre |
| publisherStr | SLU/Southern Swedish Forest Research Centre |
| record_format | eprints |
| spelling | RepoSLU55282023-11-18T02:21:06Z Simulation of rattan harvests in Indonesia : different harvesting pressures and the resulting patterns Hess, Bastian Calamus zollingeri harvesting strategies Non-Timber Forest Products (NTFP) Modelling Individual based model (IBM) Rattan Sustainability Sulawesi Indonesia The objectives of this research were to determine whether the natural rattan resources in Sulawesi, Indonesia can cope with the strongly increased harvesting pressure that has occurred over the last centuries. I was furthermore looking for patterns in the rattan population dynamics that might give a hint on how the harvesting system could be improved to ensure a maximum sustainable yield. To answer these questions, I developed an individual-based model to analyse the dynamics of rattan growth in connection with rattan harvests by locals to identify sustainable levels of rattan harvests around villages in Sulawesi, Indonesia. Scenarios with different harvesting intensities were run to compare the change in harvest amount. For a given harvesting pressure, scenarios with a high number of harvesters and a low harvesting frequency had the same effect as scenarios with high harvesting frequencies and a low number of harvesters. Scenarios with a high harvesting pressure led to a rapid decline of the harvested rattan amounts. Simulations showed that a maximum sustainable yield can be obtained as long as a harvesting pressure of 1.13 harvesting actions per month in an area of 7.07 km2 was not exceeded. Comparing the current harvesting situation with the different scenarios from the model, a long-term sustainable harvest seems unlikely, especially when considering that there is an increasing worldwide rattan demand, for which specialized rattanharvesting groups intensify their harvesting actions. To avoid further overexploitation of Indonesia’s rattan resources there is a need to manage rattan harvests. Målet med denna undersökning var att finna ut om de naturliga rottingresurserna i Sulawesi, Indonesien kan klara av kraftigt ökat skördetryck som skett under de senaste århundradena. Jag sökte dessutom mönster i rottingpopulationens dynamik som kan ge en antydan om hur avverkningen skulle kunna förbättras för att säkerställa en maximal hållbar avkastning. För att besvara dessa frågor utvecklade jag en individbaserad modell för att analysera dynamiken i rottingtillväxt i samband med rottingskördar av lokalbefolkningen. Målet var att identifiera hållbara nivåer av rottingskördar omkring byarna i Sulawesi, Indonesien. Scenarier med olika skördeintensiteter simulerades för att jämföra förändringen i skördemängderna. För en förinställd skördeintensitet hade scenarier med många skördare och en låg skördefrekvens samma effekt som scenarier med höga skördefrekvenser och ett lågt antal skördare. Scenarier med en hög skördeintensitet ledde till en snabb nedgång av skördemängderna. Simuleringarna visar att en maximal hållbar avkastning kan erhållas så länge som en skördeintensitet på 1,13 skördeåtgärder per månad i ett område på 7,07 km2 inte överskreds. När man jämför den aktuella skördesituationen med de olika scenarierna från modellen, verkar en långsiktig hållbarhet av rottingskördar mycket osannolikt; särskilt med tanke på att det finns en ökande global rottingefterfrågan för vilken specialiserade rottingskördetrupper intensifierar sina skördar. För att undvika ytterligare överexploatering av Indonesiens rottingresurser finns det ett behov av att styra rottingskördarna. Ziel dieser Arbeit war es zu untersuchen ob die natürlichen Rattanvorkommen in Sulawesi, Indonesien dem über die letzten Jahrzehnte stark angestiegenen Erntedruck standhalten können. Außerdem wurde nach Mustern in der Populationsdynamik von Rattan gesucht, die Rückschlüsse auf eine mögliche Optimierung der Ernte zulassen. Um diese Fragen zu beantworten, entwickelte ich ein individuenbasiertes Modell, das das Rattanwachstum und die Rattanernte durch lokale Dorfbewohner simuliert. Dieses Modell sollte den Bereich aufzeigen, in denen eine nachhaltige Rattannutzung im Umkreis der Dörfer in Sulawesi, Indonesien möglich ist. Verschiedene Szenarien mit unterschiedlichen Ernteintensitäten wurden simuliert um die Entwicklung und Unterschiede der Erntemengen vergleichen zu können. Dabei gab es keine Unterschiede zwischen Szenarien mit einer großen Anzahl von Rattansammlern und einer geringen Erntefrequenz und Szenarien mit einer hohen Erntefrequenz und einer kleinen Anzahl von Rattansammlern. In Szenarien mit einer hohen Ernteintensität kam es nach kurzer Zeit zu einem drastischen Rückgang der Rattan-Erntemengen. Die Simulationen zeigten, dass eine maximale nachhaltige Erntemenge möglich war, solange ein Ernte- Intensitäts-Index von 1,13 Ernteeinsätzen pro 7,07 km2 und Monat nicht überschritten wurde. Vergleicht man die momentane Erntesituation auf Sulawesi mit den verschiedenen Szenarien des Modells, scheint eine langfristig nachhaltige Rattanernte nicht möglich. Besonders unter Berücksichtigung der steigenden weltweiten Rattannachfrage, die zu einer intensivierten Ernte von einer zunehmenden Anzahl von spezialisierten Rattansammlertrupps führt. Um einen weiteren Raubbau an den indonesischen Rattanressourcen zu vermeiden, sollten die Rattan-Ernten einheitlich geregelt werden. SLU/Southern Swedish Forest Research Centre 2013 H2 eng swe ger https://stud.epsilon.slu.se/5528/ |
| spellingShingle | Calamus zollingeri harvesting strategies Non-Timber Forest Products (NTFP) Modelling Individual based model (IBM) Rattan Sustainability Sulawesi Indonesia Hess, Bastian Simulation of rattan harvests in Indonesia : different harvesting pressures and the resulting patterns |
| title | Simulation of rattan harvests in Indonesia
: different harvesting pressures and the resulting patterns |
| title_full | Simulation of rattan harvests in Indonesia
: different harvesting pressures and the resulting patterns |
| title_fullStr | Simulation of rattan harvests in Indonesia
: different harvesting pressures and the resulting patterns |
| title_full_unstemmed | Simulation of rattan harvests in Indonesia
: different harvesting pressures and the resulting patterns |
| title_short | Simulation of rattan harvests in Indonesia
: different harvesting pressures and the resulting patterns |
| title_sort | simulation of rattan harvests in indonesia
: different harvesting pressures and the resulting patterns |
| topic | Calamus zollingeri harvesting strategies Non-Timber Forest Products (NTFP) Modelling Individual based model (IBM) Rattan Sustainability Sulawesi Indonesia |