1,210 research outputs found
Modelling bark beetle disturbances in a large scale forest scenario model to assess climate change impacts and evaluate adaptive management strategies
To study potential consequences of climate-induced changes in the biotic disturbance regime at regional to national scale we integrated a model of Ips typographus (L. Scol. Col.) damages into the large-scale forest scenario model EFISCEN. A two-stage multivariate statistical meta-model was used to upscale stand level damages by bark beetles as simulated in the hybrid forest patch model PICUS v1.41. Comparing EFISCEN simulations including the new bark beetle disturbance module against a 15-year damage time series for Austria showed good agreement at province level (R² between 0.496 and 0.802). A scenario analysis of climate change impacts on bark beetle-induced damages in Austria¿s Norway spruce [Picea abies (L.) Karst.] forests resulted in a strong increase in damages (from 1.33 Mm³ a¿1, period 1990¿2004, to 4.46 Mm³ a¿1, period 2095¿2099). Studying two adaptive management strategies (species change) revealed a considerable time-lag between the start of adaptation measures and a decrease in simulated damages by bark beetle
Hoe stabiel is de toekomstboom?
Op 18 januari 2007 raasde een storm over West-Europa die tientallen dodelijke menselijke slachtoffers maakte en enorme materiële schade aanrichtte. De storm ontwortelde een miljoen bomen. Hadden we schade kunnen voorkomen of is dit het soort natuurgeweld waartegen geen kruid gewassen is? Hoofdlijnen uit Alterra rapport over "Storm, bos, beheer en stabiliteit
Survey of technical and management-based mitigation measures in forestry
Forests contribute considerably to the terrestrial carbon sink. Although the speed of uptake is generally low, the stocks in both biomass and soil are high. Within the Kyoto Protocol, active forest management can be used to reach the goals for emission reduction. In this report, an extensive list of measures is compiled detailing the ways in which forestry could contribute to an enhanced sink, or could reduce emissions. Most measures in forest management will have small effects, and these effects will generally only become visible in the long term. Effective measures can be divided into three categories; firstly, those that protect existing carbon stocks. Such measures include avoiding deforestation, not harvesting stands with high carbon contents, increased fire prevention and minimising site preparation. Secondly, those that aim to increase average carbon stocks, such as afforestation, conversion to continuous cover forestry and changes in rotation length. The third category are measures that aim at harvesting biomass to create bioenergy. Such measures could be the use of logging residues, increasing the amount of fellings aimed at bioenergy wood, the (re)introduction of pre-commercial thinnings, and the establishment of short rotation coppice
Bosbrand en klimaatverandering
Elke zomer zijn er meldingen van bosbranden in Zuid-Europa. Vooral de branden in Griekenland kregen afgelopen jaar veel media aandacht. Het weer heeft duidelijk effect op het risico op (bos)branden en het gevaar ervan. In welke mate klimaatverandering zal bijdragen is niet te zeggen. Andere factoren zijn daarbij van belang, zoals o.a. terreinomstandigheden. De terreinbeheerder kan maatregelen nemen in de sfeer van brandsingels en soortensamenstellin
Conservative interventions to improve foot progression angle and clinical measures in orthopedic and neurological patients:A systematic review and meta-analysis
To establish the comparative effects of conservative interventions on modifying foot progression angle (FPA) in children and adults with orthopaedic and neurological disease was the main aim of the literature review. Pubmed, Embase, Cinahl, and Web of Science were systematically searched for studies evaluating the effects of conservative interventions on correcting the FPA. The study protocol was registered with PROSPERO (CRD42020143512). Two reviewers independently assessed studies for inclusion and quality. Studies that assessed conservative interventions that could have affected the FPA and objectively measured the FPA were included. Within group Mean Differences (MD) and Standardized Mean Differences (SMDs) of the interventions were calculated for the change in FPA and gait performance (walking speed, stride/step length) and clinical condition (pain). Intervention effects on FPA were synthesized via meta-analysis or qualitatively. 41 studies were identified. For patients with knee osteoarthritis gait training interventions (MD = 6.69° and MD = 16.06°) were significantly more effective than mechanical interventions (MD = 0.44°) in modifying the FPA towards in-toeing (p < 0.00001). Increasing or decreasing the FPA significantly improved pain in patients with medial knee OA. Results were inconclusive for the effectiveness of gait training and mechanical devices in patients with neurological diseases. Gait feedback training is more effective than external devices to produce lasting improvements in FPA, reduce pain, and maintain gait performance in patients with medial knee OA. However, in neurological patients, the effects of external devices on improvements in FPA depends on the interaction between patient-specific impairments and the technical properties of the external device
Het Nederlandse bos in cijfers : resultaten van de 6e Nederlandse Bosinventarisatie
In 2012 is begonnen met de metingen van de 6e Nederlandse Bosinventarisatie. Twee jaar later en 85.000 bomen verder zit het werk erop en is het tijd om te kijken wat al dat meten opgeleverd heeft
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