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| 2. |
- Aronsson, Per, et al.
(författare)
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An operational decision support tool for stump harvest
- 2011
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- A multi-criteria decision support tool was developed to optimise stump harvesting for energy in Sweden. The decision tool takes account of multiple, sometimes conflicting, criteria relating to stump harvest; energy and climate, economics, biodiversity, and soil and water. Data on harvested stems are used as primary input data in the tool. Such data are routinely collected in harvester computers. The tool effectively deals with mixed sets of data; quantitative harvest data are re-calculated to metric (e.g. stump biomass), and qualitative data (e.g. biodiversity implications) are incorporated. A digital terrain map derived from air-borne laser scanning provides basic data for estimating soil wetness, while digital maps of water courses, key habitats and protected areas, or other sensitive habitats, are used to identify potentially and practically harvestable stumps.In four sub-models, an index from 0 to 10 is calculated for each stump, with 0 representing ‘Not at all suitable’ and 10 ‘Highly suitable for extraction’. Through this, a stump of high value for wood-living species is assigned a low index in the biodiversity sub-model and a large, easily accessible stump is assigned a high index in the economic sub-model. When calculating the net index, the sub-indices can be weighted according to the preferences of the end-user.An energy and climate sub-model incorporates greenhouse gas (GHG) emissions from forest operations and the effect of advancing GHG emissions when stump biomass is incinerated instead of being left to decompose. In the economic sub-model the potential monetary return from each stump is calculated based on estimated revenue from harvested stump biomass and the costs of stump harvesting and forwarding operations (based on cost functions and GIS calculations of transport distances).The biodiversity sub-model considers four types of wood-dependent organisms (lichens, mosses, insects and fungi) in terms of their habitat requirements, vulnerability, sun exposure preferences, locality, etc. A panel of external experts has drawn up a grading scale of stump values for the different taxonomic groups. The proximity to key habitats and exposure to sunlight are derived from a spatial model.Soil and water issues are handled within a sub-model estimating the consequences for long-term soil fertility (nutrient cycling and soil compaction) and water (leaching of plant nutrients and mercury, and particle transport due to soil damage by heavy machinery).The tool offers the end-user possibilities to prioritise and plan for cost-effective stump harvesting, while minimising negative environmental impacts.
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| 3. |
- Hannrup, Björn, et al.
(författare)
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Genetic parameters for spiral grain in Scots pine and Norway spruce
- 2003
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Ingår i: Silvae Genetica. - 0037-5349. ; 52:5-6, s. 215-220
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Tidskriftsartikel (refereegranskat)abstract
- Genetic parameters were estimated for grain angle, growth and exterior quality traits in two 18-year-old Scots pine (Pinus sylvestris L.) progeny trials and for grain angle and growth traits in two 12-year-old clonal trials of Norway spruce (Picea abies L. Karst.). Mean grain angles ranged 1.4 to 2.0 degrees and 2.1 to 2.6 degrees in the Scots pine and Norway spruce trials, respectively. Heritabilities for grain angle were high in Scots pine (h2>0.40) and moderate in Norway spruce (H2>0.30). The genetic standard deviations were around or slightly below one degree. In general, grain angle was genetically and phenotypically uncorrelated with the growth and exterior quality traits. All traits showed low amount of genotype by environment interaction and there was no tendency of grain angle being a more stable traits than the other traits studied. A newly developed measurement device for grain angle where the grain angle is revealed by a wedge that is pushed through the bark into the wood and follows the inclination of the tracheids was tested and found suitable for measurements in genetic tests.
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| 4. |
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| 5. |
- Jönsson, Mari, et al.
(författare)
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A spatially explicit decision support system for assessment of tree stump harvest using biodiversity and economic criteria
- 2020
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Ingår i: Sustainability. - : MDPI AG. - 2071-1050. ; 12:21
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Tidskriftsartikel (refereegranskat)abstract
- Stump harvesting is predicted to increase with future increasing demands for renewable energy. This may affect deadwood affiliate biodiversity negatively, given that stumps constitute a large proportion of the deadwood in young managed forests. Spatial decision support for evaluating the integrated effects on biodiversity and production of stump harvesting is needed. We developed a spatially explicit decision support system (called MapStump-DSS), for assessment of tree stump harvesting using biodiversity and economic criteria together with different scenarios for biodiversity conservation and bioenergy market prices. Two novel key aspects of the MAPStump-DSS is that it (1) merges and utilizes georeferenced stump-level data (e.g., tree species and diameter) directly from the harvester with stand data that are increasingly available to forest managers and (2) is flexible toward incorporating both quantitative and qualitative criteria based on emerging knowledge (here biodiversity criteria) or underlying societal drivers and end-user preferences. We tested the MAPStump-DSS on a 45 ha study forest, utilizing harvester data on characteristics and geographical positions for >26,000 stumps. The MAPStump-DSS produced relevant spatially explicit information on the biodiversity and economic values of individual stumps, where amounts of “conflict stumps” (with both high biodiversity and economical value) increased with bioenergy price levels and strengthened biodiversity conservation measures. The MAPStump-DSS can be applied in practice for any forest site, allowing the user to examine the spatial distribution of stumps and to obtain summaries for whole forest stands. Information depicted by the MAPStump-DSS includes amounts, characteristics, biodiversity values and costs of stumps in relation to different scenarios, which also allow the user to explore and optimize biodiversity and economy trade-offs prior to stump harvest.
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| 6. |
- LarsOlle, Anders, et al.
(författare)
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A multi-criteria decision support model for optimal stump harvesting
- 2012
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- A multi-criteria decision support model for optimal stump harvesting Sweden was developed. The model quantifies the effect of harvesting each individual stump over a harvesting object in four criteria's: - Biodiversity (Biodiversity value index) - Economy (SEK) - Greenhouse gas emissions (CO2) - Soil and water (Soil and water preservation index) The four criteria's are sometimes in conflict to each other, and uses values that are not directly comparable. The intended use for this model is to contribute with the objective evaluation of all four criteria's in the decision in what stumps to harvest and what stumps to leave in the harvesting object. The model uses individual stump data (e.g. position, tree species and stump biomass) and harvesting object GIS data (roads, elevation map, soil map, terrain map). Primary data on individual stumps comes from the logging system in the stem harvesters: GPS and operator classification. Such data are routinely collected in harvesters. Official map data for the harvesting object are available from the Swedish mapping, cadastral and land registration authority (Lantmäteriet). This includes the topographic map and elevation maps data in 2 m resolution. Also, GIS data are collected in the inspections before harvesting the stems. The biodiversity sub-model considers different types of wood-dependent organisms (lichens, mosses, insects and fungi) in terms of their habitat requirements, vulnerability, sun exposure preferences, locality, etc. A panel of external experts has drawn up a grading scale of stump values for the different taxonomic groups. The proximity to key habitats and exposure to sunlight are derived from a spatial model. In the economic sub-model the potential net return from each stump is calculated based on estimated revenue from harvested stump biomass and the costs of stump harvesting and transport (based on cost functions and GIS calculations of transport distances). An energy and climate sub-model incorporates greenhouse gas (GHG) emissions from forest operations and the effect of advancing GHG emissions when stump biomass is incinerated instead of being left to decompose. Soil and water issues are handled within a sub-model estimating the consequences for long-term soil fertility (nutrient cycling and soil compaction) and water (leaching of plant nutrients and mercury, and particle transport due to soil damage by heavy machinery). Each criteria is evaluated in totally four sub-models. To be able to compare the resulting value from each of the criteria, a harvesting index from 0 to 1 is calculated for each stump. The value 0 represents ‘Not at all suitable for harvest’ and 1 ‘Highly suitable for harvest’. Through this, a stump of high biodiversity value is assigned a low harvesting index in the biodiversity sub-model and a large, easily accessible stump is assigned a high harvesting index in the economic sub-model. When calculating the total net index, the harvesting index from each criteria has to be weighed together using one coefficient for each criteria. The weighing coefficient for each criteria is chosen according to the preferences of the decision maker. The tool offers the end-user possibilities to prioritise and plan for cost-effective stump harvesting, while minimising negative environmental impacts.
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| 7. |
- Larsolle, Anders, et al.
(författare)
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Modellbaserat beslutsstöd för stubbskörd [Model based decision support for stump harvest, in Swedish]
- 2017
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- In this study a decision support model for tree stump harvest was developed. The model takes into account four criteria: economy, energy and climate, biodiversity, and land and water. The value of each individual tree stump was calculated separately for each criterion. The four criteria values were then weighed together into a final suitability score for stump harvest. The final suitability score decided whether the decision support model recommended harvest of each individual tree stump or not. Data from the harvester collected at final felling was used as input to the decision support model. For each stump the values used in the model was dry mass, stump diameter, tree species and position. In addition, the harvesters log track was used as a basis for localising the terrain roads within the stand. Other geographical data used was elevation data, presence of objects with special value for biodiversity and land/water, such as key biotopes, open water and moist soil. A special study was conducted to estimate the soil stability from a topographical wetness index.The decision support model was evaluated on an existing felling 2010 in Northern Uppland. The area was 45 hectares with about 26 000 stumps. The result of the decision support model showed that general economic parameters had the greatest impact in both sensitivity and scenario analysis. The most important variable was the price for stump biomass at road side. The decision support model results left continuous areas of the stand with all stumps unharvested. The reason for this was the economy criterion's sensitivity to the local amount of stump withdrawal per hectare. Low stump withdrawal gave high harvesting costs. In that economy was the only criterion which motivated stump harvest, the model never suggested harvesting a stump unless surrounding stumps were harvested too.There is potential for developing this decision support model further using updated knowledge and examining the impact of different criteria on the final model result. The decision support model has good opportunities to serve as a comprehensive planning basis in order to ensure sustainable stump harvest.
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| 8. |
- Olsson, Bengt, et al.
(författare)
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A decision support model for individual tree stump harvesting options based on criteria for economic return and environmental protection
- 2017
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Ingår i: Scandinavian Journal of Forest Research. - : Taylor & Francis Group. - 0282-7581 .- 1651-1891. ; 32, s. 246-259
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Tidskriftsartikel (refereegranskat)abstract
- Based on principles of multi-criteria analysis techniques, a model (MAPStump-E) for decision support on stump harvesting at stand level was developed. The model applies the concept that each stump can be attributed production values (economic) and environmental values (here soil protection and water quality). Individual tree stump information was incorporated directly from the production reports of harvesters and combined with high-resolution Geographical Information System data on topography and soil type to create a production submodel and a soil and water vulnerability submodel (SWM). To test the model, it was applied to a 45-ha study forest in south-central Sweden and the outcome of nine scenarios with varying bioenergy prices and environmental protection levels was examined. Combined analysis of the effects of production and environmental criteria on total dry mass of harvestable stumps at the study site showed that biomass prices had a stronger influence than environmental criteria. Conflict stumps were defined as stumps suitable for harvest based on production criteria, but unsuitable based on soil and water protection criteria. In a ?medium? price scenario, the proportion of conflict stumps at the study site ranged from 6% to 18%, depending on protection level set.
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