Heinrich Spiecker

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In Europe temperate forests play a prominent role in timber production, nature protection, water conservation, erosion control and recreation. For centuries temperate forests in Europe have been affected by forest devastation and soil degradation. Applying great efforts to eliminate the severe wood shortage of those days, countermeasures were taken during(More)
In the Natscan project terrestrial laser scanning is used for deriving detailed information about tree quality and forest stand parameters. The authors describe an automatic method for determining tree positions and diameters at breast height (DBH) using terrestrial laser scanner data. Special attention is given to the data-processing that must be carried(More)
Laser scanner data can be used to describe the state of forests and its changes as a base for forest management activities. An automatic evaluation of typical forest parameters using laser scanner data enables the detection of trees with minimal user interaction. This paper describes an algorithm for detecting trees in a semi-automatic way. The detection(More)
We studied experimentally the effects of water availability on height and radial increment as well as wood density and tracheid properties of Norway spruce (Picea abies (L.) Karst.). The study was carried out in two long-term N-fertilization experiments in Southern Finland (Heinola and Sahalahti). At each site, one fertilized and one control plot was(More)
We evaluate genetic test plantations of North American Douglas-fir provenances in Europe to quantify how tree populations respond when subjected to climate regime shifts, and we examined whether bioclimate envelope models developed for North America to guide assisted migration under climate change can retrospectively predict the success of these provenance(More)
Based on experiences from the NATSCAN-project this contribution focuses on the evaluation of two hypotheses: (i) Terrestrial laser scanning and corresponding data analysis is ready to be used in standardized forest inventory sampling. (ii) Data quality as well as characteristics related to the technique of laser scanning widen the data base for forest(More)
High-frequency variation of Norway spruce radial increment [Picea abies (L.) Karst.] and its dependence on various climatic variables was compared in stands across latitudinal and altitudinal transects in southwestern and eastern Germany, Norway, and Finland. The tested variables included local temperature and precipitation, northern hemisphere temperature(More)
The choice between different forest management practices is a crucial step in short, medium, and long-term decision making in forestry and when setting up measures to support a regional or national forest policy. Some conditions such as biogeographically determined site factors, exposure to major disturbances, and societal demands are predetermined, whereas(More)