| 1. |
|
|
| 2. |
- Aronsson, Pär, et al.
(författare)
-
Self-Organizing Map Analysis of Planted Soil Infiltration Systems for Treatment of Log Yard Runoff
- 2009
-
Ingår i: Forest Science. - 0015-749X. ; 55, s. 183-188
-
Tidskriftsartikel (refereegranskat)abstract
- Infiltration through a soil system planted with four different species was assessed as a sustainable treatment method for logyard runoff at a field-scale experimental site in Sweden. Runoff was infiltrated through soil planted with Alnus glutinosa (L.) Gartner (common alder), Salix schwerinii X viminalis (willow variety "Gudrun"), Lolium perenne (L.) (rye grass), and Phalaris arundinacea (L.) (reed canary grass). Analyses of variance and t tests showed no significant differences in treatment when the different plants were compared with each other, and there were also no significant differences between the tree and the grass species. The infiltration treatment was effective in reducing total organic carbon and total phosphorus in the runoff even when the loads on the infiltration system increased over time. The self-organizing map (SOM) model was applied to assess the relationships between different water quality variables and to predict total nitrogen (TN) and total phosphorus (TP) concentrations. A supplementary correlation analysis confirmed the key relationships among variables revealed by the SOM. The SOM model performed very well in predicting TN and TP concentrations with the help of other water quality variables, which can be measured more cost effectively. FOR. SCI. 55(2):183-188.
|
|
| 3. |
- Blom, Åsa, et al.
(författare)
-
Durability of Untreated Norway Spruce (Picea abies) Exposed Outdoors Above Ground for Nine Years.
- 2004
-
Ingår i: Holzforschung. - 0018-3830 .- 1437-434X. ; 58:2, s. 167-172
-
Tidskriftsartikel (refereegranskat)abstract
- Moisture dynamics and durability during weather exposure as affected by origin and production method were studied for nine years on 113 untreated spruce samples. The moisture content was measured on 67 occasions. The weight loss was determined for each sample at the end of the sampling period. The most important factors, affecting both moisture content and weight loss, were origin and drying technique. The samples originating from central Sweden had the best durability, followed by the southern stand, while the northern stand had the lowest durability in terms of weight loss. Airdrying had a negative impact on the performance of samples from all three stands, but to different degrees. Samples from the northern stand were most sensitive to airdrying, in terms of both weight loss and moisture content, followed by the southern stand, while the central stand was least sensitive. Why the samples from the northern stand were more sensitive to airdrying and showed the largest weight losses is unknown; it can only be suggested that the origin of the wood can be of importance for the durability.
|
|
| 4. |
- Blom, Åsa, et al.
(författare)
-
Mass loss and moisture dynamics of Scots pine (Pinus sylvestris L.) exposed outdoors above ground in Sweden.
- 2005
-
Ingår i: Holzforschung. - 0018-3830 .- 1437-434X. ; 59:2, s. 183-189
-
Tidskriftsartikel (refereegranskat)abstract
- The durability of 566 Scots pine (Pinus sylvestris) samples was tested during a period of 9 years of exposure to weather in Sweden. The parameters investigated were heartwood/sapwood, origin, surface treatment, end-seal, storage and drying method, annual ring width and density. The weight was measured on 67 occasions during 9 years in order to assess the moisture content of the samples. The mass loss was determined for each sample at the end of the trial. Sapwood had a higher moisture uptake and a higher mass loss compared with heartwood. Even if sapwood was painted with an impermeable paint and then end-sealed, it still had higher average moisture content than heartwood. The results also demonstrated that sapwood was more sensitive to different handling conditions than heartwood. Sapwood was sensitive to air-drying and water storage, which was evident in the higher moisture uptake. In terms of mass loss, some differences were evident but they were not statistically significant due to the large standard deviation of the sapwood samples from water-stored logs. The only positive influence of water storage was on samples end-dipped in oil. One explanation could be that water storage led to increased permeability due to bacterial attack, which in turn enhanced the penetration of the oil. Heartwood had low and stable moisture dynamics during the test period, almost independent of treatment or handling conditions. No correlation with moisture uptake or mass loss was evident among annual ring width, origin or density.
|
|
| 5. |
|
|
| 6. |
- Elowson, Torbjörn
(författare)
-
Treatment of Log Yard Runoff Impacted by Aged Logs in a Free Water Surface Constructed Wetland
- 2009
-
Ingår i: Environmental Engineering Science. - : Mary Ann Liebert Inc. - 1092-8758 .- 1557-9018. ; 26, s. 1623-1632
-
Tidskriftsartikel (refereegranskat)abstract
- Hurricanes pose a great risk to forestry, and lead to high financial losses due to destroyed wood. For example, the hurricane 'Gudrun' devastated a large part of the forests of southern Sweden in January 2005. Windthrown logs are commonly removed from forest, temporarily stored on log yards, and often sprinkled with water to avoid decay. However, the subsequent runoff may cause environmental pollution. The aim of this original article is to assess the treatment of log yard runoff, which was impacted by logs of different age, in an inexpensive free water surface constructed wetland. Considering that there is often insufficient space for treatment wetlands, a small wetland was retrofitted into an existing ditch next to the log yard. Among other parameters, total organic carbon, total phosphorus, and total nitrogen were measured. Results show insufficient treatment of log yard runoff. Storage of aged windthrown logs led to a higher content of total phosphorus in the runoff. It was likely that the hydraulic loading rate in this wetland case study was too high, and that the concentration of oxygen in the runoff was too low for the biochemical processes in the wetland to reduce the concentrations of total phosphorus, total organic carbon, and suspended solids. It follows that a similar wetland treatment system to be designed in the future should either be made larger or supplemented by alternative further treatment solutions such as increased oxygenation or the introduction of aggregates promoting the adsorption of phosphorus.
|
|
| 7. |
- Hedmark, Åsa, et al.
(författare)
-
Comparison of Planted Soil Infiltration Systems for Treatment of Log Yard Runoff
- 2010
-
Ingår i: Water Environment Research. - 1061-4303. ; 82, s. 666-669
-
Tidskriftsartikel (refereegranskat)abstract
- Treatment of log yard runoff is required to avoid contamination of receiving watercourses. The research aim was to assess if infiltration of log yard runoff through planted soil systems is successful and if different plant species affect the treatment performance at a field-scale experimental site in Sweden (2005 to 2007). Contaminated runoff from the log yard of a sawmill was infiltrated through soil planted with Alnus glutinosa (L.) Gartner (common alder), Salix schweriniixviminalis (willow variety "Gudrun''), Lolium perenne (L.) (rye grass), and Phalaris arundinacea (L.) (reed canary grass). The study concluded that there were no treatment differences when comparing the four different plants with each other, and there also were no differences between the tree and the grass species. Furthermore, the infiltration treatment was effective in reducing total organic carbon (55%) and total phosphorus (45%) concentrations in the runoff, even when the loads on the infiltration system increased from year to year. Water Environ. Res., 82, 666 (2010).
|
|
