Das Varuslager im Habichtswalde bei Stift Leeden

F. Knok

Climate change and mixed forests: how do altered survival probabilities impact economically desirable species proportions of Norway spruce and European beech?

International audienceKey message Economic consequences of altered survival probabilities under climate change should be considered for regeneration planning in Southeast Germany. Findings suggest that species compositions of mixed stands obtained from continuous optimization may buffer but not completely mitigate economic consequences. Mixed stands of Norway spruce (Picea abiesL. Karst.) and European beech (Fagus sylvaticaL.) (considering biophysical interactions between tree species) were found to be more robust, against both perturbations in survival probabilities and economic input variables, compared to block mixtures (excluding biophysical interactions).ContextClimate change is expected to increase natural hazards in European forests. Uncertainty in expected tree mortality and resulting potential economic consequences complicate regeneration decisions.AimsThis study aims to analyze the economic consequences of altered survival probabilities for mixing Norway spruce (Picea abies L. Karst.) and European beech (Fagus sylvatica L.) under different climate change scenarios. We investigate whether management strategies such as species selection and type of mixture (mixed stands vs. block mixture) could mitigate adverse financial effects of climate change.MethodsThe bio-economic modelling approach combines a parametric survival model with modern portfolio theory. We estimate the economically optimal species mix under climate change, accounting for the biophysical and economic effects of tree mixtures. The approach is demonstrated using an example from Southeast Germany.ResultsThe optimal tree species mixtures under simulated climate change effects could buffer but not completely mitigate undesirable economic consequences. Even under optimally mixed forest stands, the risk-adjusted economic value decreased by 28%. Mixed stands economically outperform block mixtures for all climate scenarios.ConclusionOur results underline the importance of mixed stands to mitigate the economic consequences of climate change. Mechanistic bio-economic models help to understand consequences of uncertain input variables and to design purposeful adaptation strategies

The forest of the Ludwig-Maximilians-Universität München

In this study, the historical peculiarities and the site conditions of the forest of the Ludwig-Maximilians-Universität, München, Germany, are surveyed. Results from an extended forest inventory, which includes students' contributions, are summarized. Guidelines for current and future forest management are also discussed. The university forest supply manifold opportunities for teaching and training. In addition, they can be utilized efficiently for corresponding research projects. These forests bridge the gap between academic educational targets and actual practice. Interdisciplinary issues, research networking and links to the job market are significant requirements as well. Direct ownership by the respective university or by any other educational institution helps substantially to realize objectives in teaching and research. In the case of extemal ownership, long-lasting contracts and flexible management regulations, which grant scientific and educational liberties, are essential

A remote sensing-guided forest inventory concept using multispectral 3D and height information from ZiYuan-3 satellite data

Increased frequencies of storms and droughts due to climate change are changing central European forestsmore rapidly than in previous decades. To monitor these changes, multispectral 3D remote sensing (RS) data canprovide relevant information for forest management and inventory. In this case study, data of the multispectral3D-capable satellite system ZiYuan-3 (ZY-3) were used in a RS-guided forest inventory concept to reduce the fieldsample size compared to the standard grid inventory. We first pre-stratified the forest area via the ZY-3 datasetinto coniferous, broadleaved and mixed forest types using object-based image analysis. Each forest type wasthen split into three height strata using the ZY-3 stereo module-derived digital canopy height model (CHM).Due to limited sample sizes, we reduced the nine to six strata. Then, for each of the six strata, we randomlyselected representative segments for inventory plot placement. We then conducted field inventories in theseplots. The collected field data were used to calculate forest attributes, such as tree species composition, timbervolume and canopy height at plot level (terrestrially measured tree height and height information from ZY-3CHM).Subsequently,wecomparedtheresultingforestattributesfromtheRS-guidedinventorywiththereferencedata from a grid inventory based only on field plots. The difference in mean timber volumes to the reference was+30.21 m3ha−1(8.99 per cent) for the RS-guided inventory with terrestrial height and−11.32 m3ha−1(−3.37per cent) with height information from ZY-3 data. The relative efficiency (RE) indicator was used to comparethe different sampling schemes. The RE as compared to a random reduction of the sample size was 1.22 forthe RS-guided inventory with terrestrial height measurements and 1.85 with height information from ZY-3 data.The results show that the presented workflow based on 3D ZY-3 data is suitable to support forest inventories byreducing the sample size and hence potentially increase the inventory frequency

Die römischen Forschungen im nordwestlichen Deutschland : eine Entgegnung

von F. Knok

Neue Beiträge zu einer Geschichte der Römerkriege in Deutschland

von F. Knok

Eine Eisenschmelze im Habichtswalde bei Stift Leeden

Von F. Knok

Armin der Befreier Deutschlands : eine quellenmässige Darstellung

von Friedrich Knok

Das Schlachtfeld im Teutoburger Walde : eine Erwiderung

von F. Knok