Articles by Edgars Dubrovskis

Wildfires as natural disturbances have had important impacts on terrestrial ecosystems, including forests. We studied patterns of short-term vegetation recovery after surface fire in protected hemiboreal Pinus sylvestris L.-dominated forest. Our study was carried out near Stikli village in Western Latvia. Seven forest stands – middle-age and over-mature were sampled on nutrient-poor and mesic soils. Forest fire occurred in the summer of 2018 and covered 1440 ha of forested area. In each stand we established 16 sample plots (1 m × 1 m) in a radial pattern from the center. Every summer from 2019 till 2022 we surveyed these sample plots – recorded projective cover (%) and identified Ellenberg indicator values and species traits – plant strategy groups (C-S-R after Grime), Raunkiær life history forms and habitat types. Additionally, the occurrence of specialized fire-adapted plants was recorded. In total we identified 15 species in the ground layer, 47 species in the herbaceous layer, and 9 regenerating tree species. The colonization at the ground layer was the most rapid (projective cover increased overall by 67% in middle-aged stands and by 82% in over-mature stands). Species diversity was the highest at the herb layer during the third (middle-aged stands) and fourth (over-mature stands) after fire disturbance but showed overall declining trends. Betula spp. and Populus tremula L.-dominated regenerating tree species. The dominance of fire-adapted species declined rapidly after the fire except for moss Polytrichum spp. Overall, hemiboreal over-mature stands demonstrated higher vegetation cover and more rapid rate of initial colonization compared to middle-aged stands.

• Liepa, Latvian State Forest Research Institute “Silava”, Rīgas street 111, LV-2169, Salaspils, Latvia; Latvian University of Life Sciences and Technologies, Faculty of Forest and Environmental Sciences, Akadēmijas street 11, LV-3001, Jelgava, Latvia https://orcid.org/0000-0002-8270-6722 E-mail: liga.liepa@outlook.com
• Rendenieks, Latvian State Forest Research Institute “Silava”, Rīgas street 111, LV-2169, Salaspils, Latvia https://orcid.org/0000-0002-3511-1486 E-mail: zigmars.rendenieks@silava.lv
• Dubrovskis, Latvian University of Life Sciences and Technologies, Faculty of Forest and Environmental Sciences, Akadēmijas street 11, LV-3001, Jelgava, Latvia https://orcid.org/0000-0003-0810-5651 E-mail: edgars.dubrovskis@lbtu.lv
• Freimane, Latvian University of Life Sciences and Technologies, Faculty of Forest and Environmental Sciences, Akadēmijas street 11, LV-3001, Jelgava, Latvia E-mail: lasma.freimane@lbtu.lv
• Straupe, Latvian University of Life Sciences and Technologies, Faculty of Forest and Environmental Sciences, Akadēmijas street 11, LV-3001, Jelgava, Latvia https://orcid.org/0000-0002-2098-7194 E-mail: inga.straupe@lbtu.lv
• Jansons, Latvian State Forest Research Institute “Silava”, Rīgas street 111, LV-2169, Salaspils, Latvia https://orcid.org/0000-0001-7981-4346 E-mail: aris.jansons@silava.lv

In managed European hemiboreal forests, windstorms have a notable ecological and socio-economic impact. In this study, stand properties affecting windstorm damage occurrence at the stand-level were assessed using a Generalized Linear Mixed model. After 2005 windstorm, 5959 stands dominated by birch (Betula spp.), Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) Karst.), with mean height > 10 m were inventoried. Windstorm damage was positively associated with spruce and pine-dominated stands, increasing mean height, fresh forest edges, decreasing time since the last thinning and stronger wind gusts. Tree species composition – mixed or monodominant – was not statistically significant in the model; while, the admixture of spruce in the canopy layer was positively associated with higher windstorm damage. Stands on peat soils were more damaged than stands on mineral soils. Birch stands were more damaged than pine stands. This information could be used in forest management planning, selection of silvicultural treatments to increase forest resilience to natural disturbances.

• Donis, Latvian State Forest Research Institute “Silava”, Rigas 111, Salaspils, Latvia, LV-2169 E-mail: janis.donis@silava.lv
• Kitenberga, Latvian State Forest Research Institute “Silava”, Rigas 111, Salaspils, Latvia, LV-2169 E-mail: mara.kitenberga@gmail.com
• Šņepsts, Latvian State Forest Research Institute “Silava”, Rigas 111, Salaspils, Latvia, LV-2169 E-mail: guntars.snepsts@silava.lv
• Dubrovskis, Latvia University of Life Sciences and Technologies, Liela iela 2, Jelgava, Latvia, LV-3001 E-mail: edgars.dubrovskis@llu.lv
• Jansons, Latvian State Forest Research Institute “Silava”, Rigas 111, Salaspils, Latvia, LV-2169 E-mail: aris.jansons@silava.lv