TY - JOUR A1 - Ziche, Daniel A1 - Riek, Winfried A1 - Russ, Alexander A1 - Hentschel, Rainer A1 - Martin, Jan T1 - Water Budgets of Managed Forests in Northeast Germany under Climate Change - Results from a Model Study on Forest Monitoring Sites JF - Applied Sciences N2 - To develop measures to reduce the vulnerability of forests to drought, it is necessary to estimate specific water balances in sites and to estimate their development with climate change scenarios. We quantified the water balance of seven forest monitoring sites in northeast Germany for the historical time period 1961–2019, and for climate change projections for the time period 2010–2100. We used the LWF-BROOK90 hydrological model forced with historical data, and bias-adjusted data from two models of the fifth phase of the Coupled Model Intercomparison Project (CMIP5) downscaled with regional climate models under the representative concentration pathways (RCPs) 2.6 and 8.5. Site-specific monitoring data were used to give a realistic model input and to calibrate and validate the model. The results revealed significant trends (evapotranspiration, dry days (actual/potential transpiration < 0.7)) toward drier conditions within the historical time period and demonstrate the extreme conditions of 2018 and 2019. Under RCP8.5, both models simulate an increase in evapotranspiration and dry days. The response of precipitation to climate change is ambiguous, with increasing precipitation with one model. Under RCP2.6, both models do not reveal an increase in drought in 2071–2100 compared to 1990–2019. The current temperature increase fits RCP8.5 simulations, suggesting that this scenario is more realistic than RCP2.6 KW - evapotranspiration KW - soil moisture KW - drought KW - CMIP5 KW - RCP KW - LWF-BROOK90 KW - ICP Forest KW - soil hydrological model Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:eb1-opus-2470 SN - 2076-3417 VL - 11 IS - 5 PB - MDPI ER - TY - JOUR A1 - Blumröder, Jeanette Silvin A1 - Hoffmann, Monika T. A1 - Ilina, Olga A1 - Winter, Susanne A1 - Hobson, Peter R. A1 - Ibisch, Pierre L. T1 - Clearcuts and related secondary dieback undermine the ecological effectiveness of FSC certification in a boreal forest JF - Ecological Process N2 - Background: Over the last 25 years, the prominent forest certification system established by the Forest Stewardship Council (FSC) has used by many companies worldwide for claiming responsible forest management. The objectives of the Russian National FSC standard to decrease the size of clearcuts and the retention of forest elements such as residual seed trees need on-site validation to proof the effectiveness of FSC. To assess the ecological impacts of harvesting practices and benefits of FSC certification, we geospatially compared logging activities with and without FSC certification. Within a sample area covering approximately 3,000 km 2 in the east of the Russian Arkhangelsk Region, we used available data on tree cover loss and satellite images to assess secondary impacts of clearcuttings on adjacent remnant forests and to quantify the logging intensity. Additionally, the size and structure as well as the density of skidding trails of ten specific clearcuttings located within the sample area were surveyed using satellite images and in the field observation to delineate the boundaries of clearcuts and forested remnants within the clearcuts. Results: We found a significant increase of small-scale tree cover loss in the proximity of the clearcuts. Patchy dieback is possibly linked to the scale and intensity of logging in the surroundings. On the investigated clearcuts, FSC failed to reduce the size, to increase the retention of forest remnants including seed trees on logged areas, and to maintain larger tracts of undisturbed ground and soil compared to clearcuts that were logged before they received FSC-certification. Conclusions: Trees and forest remnants remaining inside an increasingly stressed forest ecosystem matrix may not resist further harvesting-related and climate change-induced stresses and disturbances. Large-scale clearcuttings seem to have negative impacts even in adjacent forests and undermine the ecological effectiveness of FSC certification in the study area. The Russian FSC standard is not clearly setting effective guidelines that induce a change in clearcutting practices in order to reduce ecological risks. KW - Ecological efectiveness KW - Impact assessment KW - Forest certification KW - Sustainable forestry Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:eb1-opus-2414 SN - 2192-1709 IS - 9 PB - SpringerOpen ER - TY - JOUR A1 - Berendt, Ferréol A1 - de Miguel-Diez, Felipe A1 - Wallor, Evelyn A1 - Blasko, Lubomir A1 - Cremer, Tobias T1 - Comparison of different approaches to estimate bark volume of industrial wood at disc and log scale JF - Scientific Reports N2 - Within the wood supply chain, the measurement of roundwood plays a key role due to its high economic impact. While wood industry mainly processes the solid wood, the bark mostly remains as an industrial by-product. In Central Europe, it is common that the wood is sold over bark but that the price is calculated on a timber volume under bark. However, logs are often measured as stacks and, thus, the volume includes not only the solid wood content but also the bark portion. Mostly, the deduction factors used to estimate the solid wood content are based on bark thickness. The aim of this study was to compare the estimation of bark volume from scaling formulae with the real bark volume, obtained by xylometric technique. Moreover, the measurements were performed using logs under practice conditions and using discs under laboratory conditions. The mean bark volume was 6.9 dm3 and 26.4 cm3 for the Norway spruce logs and the Scots pine discs respectively. Whereas the results showed good performances regarding the root mean square error, the coefficient of determination (R2) and the mean absolute error for the volume estimation of the total volume of discs and logs (over bark), the performances were much lower for the bark volume estimations only. KW - Environmental sciences; Physics Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:eb1-opus-1987 SN - 2045-2322 VL - 11 PB - Springer Nature ER - TY - JOUR A1 - Berendt, Ferréol A1 - Wolfgramm, Felix A1 - Cremer, Tobias T1 - Reliability of photo-optical measurements of log stack gross volume JF - Silva Fennica N2 - In terms of assessing economic impact, one of the most important elements in the wood supply chain is the measurement of round wood. Besides the one-by-one measurement of logs, logs are often measured when stacked at the forest road. The gross stacked volume includes the volume of the wood, bark and airspace and is widely used for industrial wood assortments. The increasing international attention given to photo-optical measurement systems for portable devices is due to their simplicity of use and efficiency. The aim of this study was to compare the gross volumes of hardwood log stacks measured using one widespread photo-optical app with two manual section-wise volume estimations of log stacks based on the German framework agreement for timber trade (RVR). The manual volume estimations were done starting from the left (RVRleft) and right (RVRright) sides of the log stacks. The results showed an average deviation of the photo-optical gross volume estimation in comparison to the manual estimation of –2.09% (RVRleft) and –3.66% (RVRright) while the deviation between RVRleft and RVRright was +2.54%. However, the log stack gross volume had a highly significant effect on the deviation and better accuracy with smaller deviation were reached for larger log stacks. Moreover, results indicated that the gross volume estimations of higher quality log stacks were closer for the three analyzed methods compared to estimations of poor-quality log stacks. KW - logistic KW - photogrammetry KW - timber trade KW - volume estimation KW - wood pile Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:eb1-opus-2003 SN - 2242-4075 VL - 55 IS - 3 SP - 1 EP - 13 ER - TY - JOUR A1 - Berendt, Ferréol A1 - Pegel, Erik A1 - Blasko, Lubomir A1 - Cremer, Tobias T1 - Bark proportion of Scots pine industrial wood JF - European Journal of Wood and Wood Products N2 - Bark characteristics are not only used in the forest-wood supply chain, for example to calculate standing volumes, but also to transform wood volumes and masses. In this study, bark thickness, bark volume and bark mass were analyzed on the basis of 150 Scots pine discs, with a mean diameter of 13 cm. The mean double bark thickness was 3.02 mm, the mean bark volume proportion was 5.6% and mean bark mass proportion was 3.3%. Bark proportions were significantly affected by the log-specific variables ‘diameter over bark’, ‘proportion of bark damage’ and ‘double bark thickness’. Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:eb1-opus-1975 SN - 0018-3768 VL - 79 IS - 3 SP - 749 EP - 752 PB - Springer Nature ER - TY - JOUR A1 - Berendt, Ferréol A1 - Tolosana, Eduardo A1 - Hoffmann, Stephan A1 - Alonso, Paula A1 - Schweier, Janine T1 - Harvester Productivity in Inclined Terrain with Extended Machine Operating Trail Intervals: A German Case Study Comparison of Standing and Bunched Trees JF - Sustainability N2 - The complexity of highly structured forests with multiple tree species, especially when coniferous and broadleaved tree species are mixed, as well as stands with extended machine operating trail spacing and inclined terrain, create challenging operational conditions for mechanized timber harvesting and extraction. Motor-manually felling trees within the midfield and bunching them at the machine operating trails, prior to the arrival of a harvester-forwarder system, is a complex operation. The aim of this study was to assess and compare tethered harvester productivities of a thinning operation, for felling and processing standing trees and for processing bunched trees, through a time study in forest stands with 40-m distances between machine operating trails. Total operational costs of the analyzed thinning operation were 69 €/m3o.b., including extraction using a multiple forwarder approach. Tree species, merchantable timber volume, and whether the trees were standing or presented as bunched logs all had a significant effect on the harvester time consumption. Moreover, harvester positioning time was significantly shorter when trees were already bunched at the machine operating trail. While the productivity of standing or bunched spruce trees did not differ significantly between the cases (approximately 18 m3o.b./productive machine hours excluding all delays (PMH0)), the productivity of standing broadleaved tree species (8.3 m3o.b./PMH0) was much lower than that of bunched trees (15.5 m3o.b./PMH0). Thus, the described timber harvesting and extraction system may be a valuable option for forest stands with high proportion of broadleaved trees. KW - forest operations KW - machine operating trail KW - midfield KW - single-grip harvester KW - soil protection KW - tethering winch Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:eb1-opus-2022 SN - 2071-1050 VL - 12 IS - 21 PB - MDPI ER - TY - RPRT A1 - Cremer, Tobias A1 - Berendt, Ferréol A1 - de Miguel Diez, Felipe A1 - Wolfgramm, Felix A1 - Blasko, Lubomir T1 - Accuracy of Photo-Optical Measurement of Wood Piles T2 - Environmental Sciences Proceedings N2 - The accurate estimation of timber volume is of the utmost importance. For industrial timber, the volume is often estimated as stacked cubic meters. In addition to manual measurements, volume estimation is possible with photo-optical systems. Over 100 piles of industrial timber of broadleaved tree species were analyzed. In the study, a standard manual measurement method for the estimation of wood pile volumes was compared with a smartphone based photo-optical application for the determination of woodpile volume. Mean gross volume of the piles was approximately 56 m3 and mean width of piles was 9.43 m. A strong correlation was found between the manual measurements and the photo-optical measurement. However, volume estimation of large volume piles seems to perform better in comparison to piles with small volumes. Further research is needed to determine the effects of variables such as log quality or quality of pile on volume estimation accuracy. KW - timber stack KW - volume estimation KW - logistic KW - timber trade Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:eb1-opus-2012 SN - 2673-4931 IS - 3(1) PB - MDPI ER - TY - CHAP A1 - Berendt, Ferréol A1 - Pegel, Erik A1 - Blasko, Lubomir A1 - Cremer, Tobias T1 - Bark Characteristics of Scots Pine Logs T2 - Environmental Sciences Proceedings N2 - The wood of Scots pine (Pinus sylvestris L.) shows... KW - bark thickness KW - bark volume KW - bark damage KW - industrial wood Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:eb1-opus-2040 SN - 2673-4931 PB - MDPI ER - TY - JOUR A1 - Blumröder, Jeanette Silvin A1 - May, Felix A1 - Härdtle, Werner A1 - Ibisch, Pierre L. T1 - Forestry contributed to warming of forest ecosystems in northern Germany during the extreme summers of 2018 and 2019 JF - Ecological Solutions and Evidence N2 - 1. Forest management influences a variety of ecosystem structures and processes relevant to meso- and microclimatic regulation, but little research has been done on how forest management can mitigate the negative effects of climate change on forest ecosystems. 2. We studied the temperature regulation capacity during the two Central European extreme summers in 2018 and 2019 in Scots pine plantations and European beech forests with different management-related structural characteristics. 3. We found that the maximum temperature was higher when more trees were cut and canopy was more open. Logging 100 trees per hectare increased maximum temperature by 0.21–0.34 K at ground level and by 0.09–0.17 K in 1.3 m above ground. Opening the forest canopy by 10% significantly increased Tmax, measured 1.3 m above ground by 0.46 K (including pine and beech stands) and 0.35 K (only pine stands). At ground level, Tmax increased by 0.53 K for the model including pine and beech stands and by 0.41 K in pure pine stands. Relative temperature cooling capacity decreased with increasing wood harvest activities, with below average values in 2018 (and 2019) when more than 656 (and 867) trees per hectare were felled. In the pine forests studied, the relative temperature buffering capacity 1.3 m above ground was lower than average values for all sample plots when canopy cover was below 82%. In both study years, mean maximum temperature measured at ground level and in 1.3 m was highest in a pine-dominated sample plots with relatively low stand volume (177 m3 ha−1) and 9 K lower in a sample plot with relatively high stock volumes of Fagus sylvatica (>565 m3 ha−1). During the hottest day in 2019, the difference in temperature peaks was more than 13 K for pine-dominated sample plots with relatively dense (72%) and low (46%) canopy cover. 4. Structural forest characteristics influenced by forest management significantly affect microclimatic conditions and therefore ecosystem vulnerability to climate change. We advocate keeping the canopy as dense as possible (at least 80%) by maintaining sufficient overgrowth and by supporting deciduous trees that provide effective shade. KW - climate change KW - forest functionality KW - regulating ecosystem services KW - cooling KW - drought events KW - forest canopy KW - temperature regulation Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:eb1-opus-1992 SN - 2688-8319 VL - 2 IS - 3 PB - Wiley ER -