10 research outputs found
Auswirkungen von KlimaÀnderungen auf den Wasserhaushalt von WÀldern im Hessischen Ried
Die WÀlder im Hessischen Ried sind geprÀgt durch hohen Nutzungsdruck, hÀufigen Trockenstress und daraus resultierend starken WaldschÀden.
Die im Rahmen des Projektes INKLIM 2012 II PLUS durchgefĂŒhrten Wasserhaushaltssimulationen zeigten, dass die
Wasserversorgung der BestĂ€nde bereits in der Vergangenheit teilweise extrem eingeschrĂ€nkt war, was als Ursache der vielfach beschriebenen WaldschĂ€den zu bewerten ist. Simulationen mit IPCC-SRES-Klimaprojektionsdaten ergaben, dass zukĂŒnftig hĂ€ufiger mit Ă€hnlichen Trockenperioden zu
rechnen ist. Zur Sicherung der StabilitĂ€t der WaldbestĂ€nde ergibt sich daraus fĂŒr die Forstwirtschaft ein extrem eingeschrĂ€nkter Handlungsrahmen in Bezug auf Umtriebszeiten, Zeitpunkt und IntensitĂ€t von DurchforstungsmaĂnahmen sowie der Baumartenwahl
BodenvorrĂ€te & Bilanzen von MakronĂ€hrstoffen als Indikatoren fĂŒr die ökologische Bewertung intensiver Biomassenutzung im Wald
Die mögliche NutzungsintensitĂ€t von WaldbestĂ€nden wird hĂ€ufig anhand einzelner Indikatoren wie den NĂ€hrstoffvorrĂ€ten im effektiven Wurzelraum (AKe), dem NĂ€hrstoffentzugsindex oder der Stoffbilanz bewertet. Dabei ergeben sich fĂŒr die hier untersuchten FlĂ€chen des Intensiven Umweltmonitorings fĂŒr Kalium und Magnesium groĂe Differenzen zwischen den betrachteten Indikatoren, dagegen fĂŒr Calcium ein eher undifferenziertes Bild. Aufgrund der uneinheitlichen Ergebnisse ist es erforderlich, die Indikatoren hinsichtlich ihrer Aussage genau zu ĂŒberprĂŒfen. Gleichzeitig sollte die Ableitung von standortspezifischen Empfehlungen fĂŒr eine angemessene NutzungsintensitĂ€t und den Bedarf an KompensationsmaĂnahmen (z. B. Kalkung) unbedingt unter BerĂŒcksichtigung aller potenziellen Indikatoren erfolgen
Quantifying the effect of persistent dryer climates on forest productivity and implications for forest planning: a case study in northern Germany
Abstract Background Forest management decisions are based on expectations of future developments. For sound decisions it is essential to accurately predict the expected values in future developments and to account for their inherent uncertainty, for example the impact of climate change on forests. Changing climatic conditions affect forest productivity and alter the risk profile of forests and forest enterprises. Intensifying drought stress is seen as one major risk factor threatening forest management in the north German lowlands. Drought stress reduces tree growth and vitality and might even trigger mortality. But so far, it is not possible to quantify effects of a persistent dryer climate on forest productivity at a level suitable for forest management. Methods We apply a well-established single-tree forest growth simulator to quantify the effect of persistent dryer climates on future forest productivity. We analyse the growth of Scots pine (Pinus sylvestris L.), European beech (Fagus sylvatica L.) and oak (Quercus robur L. and Quercus petraea (Matt.) Liebl.) in two forest regions in the north German lowlands for a time interval of 60 years until 2070. The growth response under three different climate projections is compared to a baseline scenario. Results The results show clear differences in volume increment to persistent dryer climates between tree species. The findings exhibit regional differences and temporal trends. While mean annual increment at biological rotation age of Scots pine and oak predominantly benefits from the projected climate conditions until 2070, beech might suffer losses of up to 3 m3·haâ1·yrâ1 depending on climate scenario and region. However, in the projection period 2051 to 2070 the uncertainty ranges comprise positive as well as negative climatic effects for all species. Conclusions The projected changes in forest growth serve as quantitative contributions to provide decision support in the evaluation of, for example, species future site suitability and timber supply assessments. The analysis of productivity changes under persistent dryer climate complements the drought vulnerability assessment which is applied in practical forestry in northwestern Germany today. The projected speciesâ productivity has strong implications for forest management and the inherent uncertainty needs to be accounted for
Is Biomass Accumulation in Forests an Option to Prevent Climate Change Induced Increases in Nitrate Concentrations in the North German Lowland?
The North German Lowland is a region with locally high nitrate (NO3â) concentrations in seepage water, inducing an increased susceptibility to the effects of climate change. The future risk of rising NO3â concentrations in seepage water from forests was quantified for four regions in the North German Lowland using climate projections and a modelling system comprising submodels for forest stand development (WaldPlaner), water budgets (WaSiM-ETH), and biogeochemical element cycles (VSD+). The simulations for the period from 1990 to 2070 included three different forest management scenarios (reference, biodiversity, and climate protection) and showed a general decrease in groundwater recharge which could hardly be influenced by any of the management options. The simulated soil organic matter stocks adequately represented their past increase as expected from the National Forest Soil Inventory (NFSI), but also showed a future decline under climate change conditions which leads to higher organic matter decomposition and a long-lasting increase of NO3â leaching from forest soils. While the climate protection oriented scenario shows the highest increase in NO3â concentrations during the projection period until 2070, the biodiversity scenario kept NO3â concentrations in seepage water below the legal thresholds in three of four selected model regions
Tree Species Selection in the Face of Drought RiskâUncertainty in Forest Planning
Rapid climate change leads to significant shifts in the site-productivity relationship of tree species and alters abiotic and biotic risks well beyond classical rotation ages on many forest sites worldwide. Forest conversion may be an adequate measure to counter possible negative effects of climate change. Unfortunately, climate-driven changes in abiotic and biotic risks bear a significant source of intrinsic uncertainty inherent in climate projections. It is our goal to appraise uncertainty in species selection under drought stress, one of the most important risk factors for many forests. We derive a method to assess drought restrictions and demonstrate the uncertainty in the process of species selection by applying three climate scenarios. Furthermore, we interpret the consequences of climate uncertainty in the light of different management goals, i.e., a business-as-usual silviculture, a climate protection strategy favoring CO2 sequestration and a biodiversity strategy increasing diversity. The methods are applied to two representative regions in the North German Plain. The results clearly show the strong need for adaptive planning when drought restrictions are considered. However, different silvicultural management objectives may alter the extent of adaptive planning. The uncertainty in the planning process arising from different underlying climate projections strongly depends on the regional site characteristics and on forest management strategy. In conclusion, it is most important in forest planning to clearly state the management goals and to carefully explore if the goals can be met under climate change and if the uncertainty due to climate projections significantly affects the results of species selection
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Auswirkungen des Klimas und der Landnutzung sowie ihrer Ănderungen auf die WasserverfĂŒgbarkeit und auf Hochwasserereignisse in Europa : gemeinsamer Schlussbericht zum BMBF-Projektverbund mit den Einzelprojekten "Einfluss des Klimawandels auf WasserverfĂŒgbarkeit und Hochwasser in Deutschland und Europa: eine integrierte Analyse", "WasserverfĂŒgbarkeit und Hochwasserabfluss (Elbe- und Odergebiet) in AbhĂ€ngigkeit von Klima und Landnutzung und deren Ănderungen", "Modellierung des Abflusses im Oberlauf der Oder fĂŒr Extremereignisse"
[no abstract available
The Potential of EnMAP and Sentinel-2 Data for Detecting Drought Stress Phenomena in Deciduous Forest Communities
Pilotstudie zu den lokalen Auswirkungen des Klimawandels auf die Forstwirtschaft in ausgewÀhlten Regionen Sachsen-Anhalts
Softcover, 17x24SĂ€mtliche Klimaprojektionen lassen fĂŒr Sachsen-Anhalt einen deutlichen Temperaturanstieg
bei gleichzeitig verÀnderter saisonaler Niederschlagsverteilung erwarten. Von den Folgen
des Klimawandels wird insbesondere die langfristig handelnde Forstwirtschaft betroffen sein,
da sich die Produktionsgrundlagen, die Risiken und die Ertragsaussichten wesentlich verÀndern.
In der vorliegenden Pilotstudie sind in ausgewÀhlten Regionen Sachsen-Anhalts auf
der Basis rÀumlich hoch aufgelöster Klima-, Standort-, Bestandes- und Risikoinformationen
Entscheidungshilfen fĂŒr das operationale Handeln von Forstbetrieben entwickelt worden. Als
Modellregionen dienen der Oberharz, der FlÀming und die Colbitz-Letzlinger Heide