TY - JOUR A1 - Bose, Arun K. A1 - Scherrer, Daniel A1 - Camarero, j. Julio A1 - Ziche, Daniel A1 - Babst, Flurin A1 - Bigler, Christof A1 - Bolte, Andreas A1 - Dorado-Liñán, Isabel A1 - Etzold, Sophia A1 - Fonti, Patrick A1 - Forrester, David I. A1 - Gavinet, Jordane A1 - Gazol, Antonio A1 - González de Andrés, Ester A1 - Karger, Dirk Nikolaus A1 - Lebourgeois, Francois A1 - Lévesque, Mathieu A1 - Martínez-Sancho, Elisabet A1 - Menzel, Annette A1 - Neuwirth, Burkhard A1 - Nicolas, Manuel A1 - Sanders, Tanja G. M. A1 - Scharnweber, Tobias A1 - Schröder, Jens A1 - Zweifel, Roman A1 - Gessler, Arthur A1 - Rigling, Andreas T1 - Climate sensitivity and drought seasonality determine post-drought growth recovery of Quercus petraea and Quercus robur in Europe JF - Science of The Total Environment N2 - Recent studies have identified strong relationships between delayed recovery of tree growth after drought and tree mortality caused by subsequent droughts. These observations raise concerns about forest ecosystem services and post-drought growth recovery given the projected increase in drought frequency and extremes. For quantifying the impact of extreme droughts on tree radial growth, we used a network of tree-ring width data of 1689 trees from 100 sites representing most of the distribution of two drought tolerant, deciduous oak species (Quercus petraea and Quercus robur). We first examined which climatic factors and seasons control growth of the two species and if there is any latitudinal, longitudinal or elevational trend. We then quantified the relative departure from pre-drought growth during droughts, and how fast trees were able to recover the pre-drought growth level. Our results showed that growth was more related to precipitation and climatic water balance (precipitation minus potential evapotranspiration) than to temperature. However, we did not detect any clear latitudinal, longitudinal or elevational trends except a decreasing influence of summer water balance on growth of Q. petraea with latitude. Neither species was able to maintain the pre-drought growth level during droughts. However, both species showed rapid recovery or even growth compensation after summer droughts but displayed slow recovery in response to spring droughts where none of the two species was able to fully recover the pre-drought growth-level over the three post-drought years. Collectively, our results indicate that oaks which are considered resilient to extreme droughts have also shown vulnerability when droughts occurred in spring especially at sites where long-term growth is not significantly correlated with climatic factors. This improved understanding of the role of drought seasonality and climate sensitivity of sites is key to better predict trajectories of post-drought growth recovery in response to the drier climate projected for Europe. KW - Climate change KW - Warming KW - Drought KW - Legacy effects KW - Acclimation KW - Tree rings Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:eb1-opus-2609 SN - 1879-1026 VL - 784 PB - Elsevier ER - 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 - CHAP A1 - Riek, Winfried A1 - Russ, Alexander A1 - Ziche, Daniel A1 - Hentschel, Rainer A1 - Brini, Andrea T1 - Prognose zur Entwicklung der Rot-Buche unter veränderten Wasserhaushaltsbedingungen T3 - Eberswalder forstliche Schriftenreihe - 71 Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:eb1-opus-5276 SP - 104 EP - 128 ER - TY - JOUR A1 - Ziche, Daniel A1 - Grüneberg, Erik A1 - Riek, Winfried A1 - Wellbrock, Nicole ED - Johann Heinrich von Thünen-Institut, T1 - Vergleich der Daten der LUCAS 2015-Inventur und der zweiten Bodenzustandserhebung im Wald : Untersuchungen zur Vergleichbarkeit und Repräsentanz zweier bodenkundlicher Inventuren in Deutschland T2 - Thünen Report; 94 N2 - Die Produktivität von Waldökosystemen wird durch die Bereitstellung von Nährstoffen und Wasser gewährleistet. Somit ist das Wissen über die chemischen und physikalischen Eigenschaften der Böden essentiell sowohl zur Beurteilung des Bodenzustands als auch der Güte des Waldstandorts. Hierfür können Daten aus zwei bundesweiten Bodenzustandserhebung im Wald (BZE-Wald) von über 1.800 Probepunkten eines 8 x 8 km-Grundrasters herangezogen werden. Die Erhebungen fanden zwischen 1986 bis 1994 (BZE I-Wald) und 2006 bis 2008 (BZE II-Wald) nach einheitlichem Aufnahmeverfahren statt. Das LUCAS-Projekts zielt auf die Erstellung eines harmonisierten Datensatz zur Landbedeckung und Landnutzung innerhalb der Europäischen Union (EU). Das Europäische Datenzentrum (ESDAC) stellt 265.000 georeferenzierte Punkte auf einem 2 x 2 km-Raster bereit, die jeweils in den Jahren 2009 und 2015 an 10 % der Punkte am gleichen Standort beprobt wurden. Angesichts von zwei parallellaufender Bodeninventuren stellt sich die Frage einer potentiellen Verknüpfung miteinander. In dieser Studie werden die LUCAS-Bodendaten der Inventur des Jahres 2015 mit den entsprechenden bundesweiten BZE-Daten verglichen und auf ihre Repräsentativität überprüft. Um eine flächengewichtete Hochrechnung für Deutschland zu ermöglichen, erfolgte eine Zordnung der Inventurpunkte des LUCAS-Programms anhand ihrer Koordinaten zu den bei der bundesweiten BZE-Auswertung verwendeten 16 BZE-Substratklassen. Alle Klassen wurden hinsichtlich signifikanter und systematischer Unterschiede zwischen beiden Inventuren überprüft. Darüber hinaus wurden die BZE-Daten dahingehend evaluiert, inwieweit die ausschließlich im LUCAS Programm verwendete Tiefenstufe 0-20 cm im Vergleich zum Mineralboden bis in 90 cm Tiefe und der Humusauflage bei der Berechnung von Vorräten zukommt. Der Vergleich der bodenchemischen Kennwerte ergab deutliche Unterschiede zwischen den Inventuren. Sowohl die pH(H2O)-Werte als auch die C/N-Verhältnisse waren bei LUCAS 2015 niedriger, die Konzentrationen von C und N jedoch höher als bei der BZE II. Die Vorräte an Kohlenstoff und Sticksoff weisen noch größere Abweichungen gegenüber der BZE II aufgrund der Unsicherheiten bei der Ableitung von Trockenrohdichten aus Kartenmaterial auf. Im Gegensatz dazu erfolgte durch die BZE II eine volumenbezogene Beprobung an fast allen Standorten. Eine Ableitung von Trockenrohdichten aus Kartenmaterial führt bei der LUCAS-Inventur zu einer hohen Unsicherheit der Ergebnisse und zu einer Überschätzung von Vorratsänderungen. Die höheren Kohlenstoff- und Stickstoffkonzentrationen bei der LUCAS-Inventur könnte an einer unzureichend genauen Trennung der organischen Auflage vom Mineralboden liegen, da dieser durch Bestandteile der Auflage aufkonzentriert würde. Während der Erhebung der BZE-Wald wurde explizit auf die systematische Trennung beider Kompartimente geachtet. Weiterhin steht die Anzahl der beprobten LUCAS-Waldpunkte im Missverhältnis zur Waldfläche, da in Nord- und Süddeutschland zu wenig Probepunkte vorkamen. Allerdings sind die Waldanteile der LUCAS-Gesamtinventur mit denen der dritten Bundeswaldinventur vergleichbar. Die Stichprobengröße von LUCAS 2015 umfasst etwa 25 % der BZE II-Stichprobe. Hierdurch sind einige Substrattypen nur unzureichend belegt, weshalb zum einen wesentliche Bodeneigenschaften unberücksichtigt blieben und andererseits eine flächengewichtete Hochrechnung erschwert werden würde. Infolge der geringeren Stichprobe weichen die bodenchemischen Kennwerte der einzelnen Substratgruppen zwischen den Messnetzen ab. Außerdem erhöhen sich die Unsicherheiten durch die Reduzierung der Stichprobe. Somit ließen sich Bodenveränderungen bei einer Wiederholungsinventur schwerer detektieren. Die Daten aus den Bodeninventuren sind für die Treibhausgasberichterstattung relevant, da Kohlenstoffvorräten für die organische Auflage und für den Mineralboden bis zu einer Tiefe von mindestens 30 cm zu berichten sind. Im Mittel werden nach den Daten der BZE II 16 % des bis 90 cm Tiefe vorkommenden Kohlenstoffs in der Auflage gespeichert, wobei diese mit der LUCAS-Inventur nicht beprobt wurde. Der in der organischen Auflage gebundene Kohlenstoff ist vulnerabel gegenüber Klima- und Umwelteinflüssen, so dass eine Auswertung diesbezüglich nicht möglich ist. Weiterhin wurde bei LUCAS 2015 nur die oberen 20 cm des Mineralbodens beprobt und damit lediglich 42 % des bei der BZE II abgeschätzten Kohlenstoffs erfasst. Durch das Fehlen der Auflage und die geringere Tiefe sind die Daten aus LUCAS 2015 nur eingeschränkt für die Treibhausgasberichterstattung nutzbar. Aufgrund einer geringeren Repräsentativität sowie größeren Unsicherheiten und Diskrepanzen von LUCAS 2015 gegenüber der BZE im Wald würde eine Vereinigung beider Datensätze keine zusätzlichen Synergien erzeugen. N2 - The productivity of forest ecosystems depends on the supply of both nutrients and water by soils. Therefore, the knowledge of the chemical and physical soil properties is crucial for assessing the soil condition as well as the quality of forest sites. For this purpose, data are available from two nationwide Forest Soil Inventories (NFSI) on more than 1,800 sample plots of an 8 x 8 km grid. The inventories were conducted between 1986 and 1994 (NFSI I) and 2006 and 2009 (NFSI II) in accordance with harmonized surveying techniques. The LUCAS Project aims at the development of a harmonized dataset on land cover and land use within the European Union (EU). Approximately 265.000 georeferenced plots on a 2 x 2 km grid were available from the European Soil Data Centre (ESDAC). Soil samples were taken in 2009 and in 2015 at approximately 10 % of these plots at the same locations. Considering two almost parallel running soil inventories, questions have arisen to their potential links to one another. In this study, the LUCAS soil data from the 2015 inventory were compared with the corresponding NFSI II data and reviewed under the aspect of representativeness. In order to enable an area weighted estimation for Germany the plots of the LUCAS program were attributed to the same 16 soil parent material groups used in the German NFSI data using geographical coordinates. All classes were tested for significant and systematic differences between the inventories. To quantify C stocks, it is important to compare the depth level 0-20 cm of the LUCAS program to Germanies NFSI sampling scheme, where data available for the organic layer and the mineral soil down to 90 cm. The comparison of various chemical soil parameters showed clear differences between the inventories. The pH(H2O) and the C/N ratio derived from LUCAS 2015 was lower while carbon (C) and nitrogen (N) concentrations were higher compared to the NFSI II. The C and N stocks deviate even more from the NFSI II due to uncertainties in the estimation of bulk densities derived from maps. By contrast Germany’s NFSI, were volume-based sampling was obligatory for almost all plots. As a result, fine earth stock estimates from map derived bulk densities could result in highly uncertain and overestimated stocks change rates. Higher C and N concentrations of the LUCAS inventory could be attributed to an insufficient separation of the organic layer from the mineral soil because if the separation is not practiced carefully, residues of the organic layer can contaminate the mineral soil sample and cause significant higher concentrations. The soil sampling of the NFSI focused explicitly of the systematic separation of both compartments. The number of the sampled forest plots of LUCAS 2015 showed a lack of representativeness because in the northern and southern parts of Germany an insufficient number of plots were sampled. Nevertheless, the proportion of the forest area of the total LUCAS inventory is comparable with Germany’s Third National Forest Inventory. The selected LUCAS 2015 samples comprise 25 % of the NFSI II plots which results in an insufficient coverage of various soil groups. This means that soil properties remain unconsidered and that the area-weighted extrapolation could become more difficult. Chemical soil parameter within in individual substrate groups differed between the sampling grids due to the smaller sample of LUCAS 2015 compared to the NFSI II. Moreover, the reduction of sampling plots results in an increase of uncertainties. Thus, the detection of changes in soil conditions could be more difficult in respect to repeated sampling. Soil inventory data are of importance in greenhouse gas reporting because C stocks the organic layer and the mineral soil down to 90 cm must be reported. The analysis of the NFSI II revealed that the organic layer comprises 16 % of the C stored in the entire soil profile. The organic layer was not sampled in the LUCAS inventory. Nevertheless, changes in C stored in the organic layer is vulnerable to impacts of climate and other environmental and anthropogenic variables but the effects cannot be considered with LUCAS 2015. Due to the LUCAS 2015 mineral soil sampling depth down to 20 cm only 42 % of the stored C was detected in the entire soil profile. Therefore, data based on LUCAS 2015 are insufficiently qualified for the greenhouse gas reporting due to the lack of a sampled organic layer and the limitation to the sampling depth of 20 cm. Compared to Germany’s NFSI, the results based on the LUCAS inventory revealed a smaller representativity and were associated with larger uncertainties as well as discrepancies. Consequently, the union of both data sets will not result in additional synergies. T2 - Comparison of the LUCAS 2015 inventory with the second National Forest Soil Inventory : Comparability and representativeness of two soil inventories conducted in Germany KW - Boden; Wald; Inventur; Probenahme; Karten; Konzentrationen; Vorräte; Kohlenstoff; Stickstoff; pH-Wert; Trockenrohdichte; Unsicherheiten; Harmonisierung; Repräsentativität KW - Soil; Forest; Monitoring; Inventory; Sampling; Mapping; Stocks; Concentrations; Carbon; Nitrogen; pH-Value; Bulk density; Uncertainties; Representativity; Harmonisation Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:eb1-opus-5314 UR - https://literatur.thuenen.de/digbib_extern/dn064841.pdf SN - 978-3-86576-239-9 SN - 2196-2324 PB - Thünen-Institut, Bundesforschungsinstitut für Ländliche Räume, Wald und Fischerei ER - TY - JOUR A1 - Bose, Arun K. A1 - Gessler, Arthur A1 - Bolte, Andreas A1 - Bottero, Alessandra A1 - Buras, Allan A1 - Cailleret, Maxime A1 - Camarero, J. Julio A1 - Haeni, Matthias A1 - Hereş, Ana-Maria A1 - Hevia, Andrea A1 - Lévesque, Mathieu A1 - Linares, Juan C. A1 - Martinez-Vilalta, Jordi A1 - Matías, Luis A1 - Menzel, Annette A1 - Sánchez-Salguero, Raúl A1 - Saurer, Matthias A1 - Vennetier, Michel A1 - Ziche, Daniel A1 - Rigling, Andreas T1 - Growth and resilience responses of Scots pine to extreme droughts across Europe depend on predrought growth conditions JF - Global Change Biology N2 - Global climate change is expected to further raise the frequency and severity of extreme events, such as droughts. The effects of extreme droughts on trees are difficult to disentangle given the inherent complexity of drought events (frequency, severity, duration, and timing during the growing season). Besides, drought effects might be modulated by trees’ phenotypic variability, which is, in turn, affected by long-term local selective pressures and management legacies. Here we investigated the magnitude and the temporal changes of tree-level resilience (i.e., resistance, recovery, and resilience) to extreme droughts. Moreover, we assessed the tree-, site-, and drought-related factors and their interactions driving the tree-level resilience to extreme droughts. We used a tree-ring network of the widely distributed Scots pine (Pinus sylvestris) along a 2,800 km latitudinal gradient from southern Spain to northern Germany. We found that the resilience to extreme drought decreased in mid-elevation and low productivity sites from 1980–1999 to 2000–2011 likely due to more frequent and severe droughts in the later period. Our study showed that the impact of drought on tree-level resilience was not dependent on its latitudinal location, but rather on the type of sites trees were growing at and on their growth performances (i.e., magnitude and variability of growth) during the predrought period. We found significant interactive effects between drought duration and tree growth prior to drought, suggesting that Scots pine trees with higher magnitude and variability of growth in the long term are more vulnerable to long and severe droughts. Moreover, our results indicate that Scots pine trees that experienced more frequent droughts over the long-term were less resistant to extreme droughts. We, therefore, conclude that the physiological resilience to extreme droughts might be constrained by their growth prior to drought, and that more frequent and longer drought periods may overstrain their potential for acclimation. KW - acclimation KW - latitudinal gradient KW - Pinus sylvestris KW - predisposition KW - tree rings Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:eb1-opus-5496 SN - 1365-2486 VL - 26 IS - 8 SP - 4521 EP - 4537 PB - Wiley ER -