Dominik Seidel

Georg-August-Universität Göttingen | GAUG · Spatial structures and digitization of forests

The three-dimensional forest structure affects many ecosystem functions and services provided by forests. As forests are made of trees it seems reasonable to approach their structure by investigating individual tree structure. Based on three-dimensional point clouds from laser scanning, a newly developed holistic approach is presented that enables...

Aboveground tree architecture is neither fully deterministic nor random. It is likely the result of mechanisms that balance static requirements and light‐capturing efficiency. Here, we used terrestrial laser scanning data to investigate the relationship between tree architecture, here addressed using the box‐dimension (Db), and the architectural be...

Management for complexity has become an important paradigm for European and North American forestry. Recent advancements in data processing allow for a detailed, three-dimensional and objective quantification of structural complexity in forests based on terrestrial laser scanning data. In our study, we used such 3D data from an exemplary temperate...

Laser scanning has revolutionized the ability to quantify single-tree morphologies and stand structural variables. In this study, we address the issue of occlusion when scanning a spruce (Picea abies (L.) H.Karst.) and beech (Fagus sylvatica L.) forest with a mobile laser scanner by making use of a unique study site setup. We scanned forest stands...

Forest management has a direct influence on the structure and stability of forests. In this study, we used the 3D data from mobile laser scanning in real forest stands dominated by European beech (Fagus sylvatica L.) to simulate different silvicultural treatments and assess their impact on the structural complexity and short-term economic return. F...

Intensification of land use by humans has led to a homogenization of landscapes and decreasing resilience of ecosystems globally due to a loss of biodiversity, including the majority of forests. Biodiversity-ecosystem functioning (BEF) research has provided compelling evidence for a positive effect of biodiversity on ecosystem functions and service...

Managing forests for increased structural complexity as well as acknowledging them as ‘complex adaptive systems’ has become a paradigm in modern silviculture. Primary forests usually show greater structural complexity than managed forests since forest management often aims for several reasons at less complex but specific structures, e.g. for the pr...

Norway spruce (Picea abies (L.) H.Karst) trees planted with high stem densities produce finely branched, solid logs but are vulnerable to extreme weather events, e.g., storms. Over the last decades spruce stands have been planted at lower stand densities, resulting in wider crowns, lower crown bases, and higher stand stability, but this might decre...

Climate is a critical variable in determining the productivity and structural complexity of forest ecosystems. Under similar temperature regimes and other site conditions, precipitation becomes fundamental for forest regeneration and growth, and eventually for the development of structural complexity and patterns in forest productivity. Empirical q...

The adaptation of forest management to changing environmental conditions due to climate change relies on information on the current forest and tree vitality. In common practice, the percentage of crown defoliation is used as a proxy for tree vitality, an approach that has several drawbacks. By performing laser scanning on a forest plot in the Haini...

Today, creating or maintaining forest structural complexity is a management paradigm in many countries due to the positive relationships between structural complexity and several forest functions and services. In this study, we tested whether the box-dimension (Db), a holistic and objective measure to describe the structural complexity of trees or...

Just as the aboveground tree organs represent the interface between trees and the atmosphere, roots act as the interface between trees and the soil. In this function, roots take-up water and nutrients, facilitate interactions with soil microflora, anchor trees, and also contribute to the gross primary production of forests. However, in comparison t...

The dynamics of forest structure influence forest ecosystem functions and are modified by forest management and natural disturbances. Here, we quantified the dynamics of stand structural complexity of differently managed and unmanaged European beech (Fagus sylvatica L.) forests. We determined changes of different aspects of stand structural complex...

Mixed forests make up the majority of natural forests, and they are conducive to improving the resilience and resistance of forest ecosystems. Moreover, it is in the crown of the trees where the effect of inter-and intra-specific interaction between them is evident. However, our knowledge of changes in crown morphology caused by density, competitio...

Many Indonesian forests have been cleared and replaced by fast-growing cash crops (e.g., oil palm and rubber plantations), altering the vegetation structure of entire regions. Complex vegetation structure provides habitat niches to a large number of native species. Airborne laser scanning (ALS) can provide detailed three-dimensional information on...

Urban forests are part of the global forest network, providing important benefits to human societies. Advances in remote-sensing technology can create detailed 3D images of trees, giving novel insights into tree structure and function. We used terrestrial laser scanning and quantitative structural models to provide comprehensive characterizations o...

Key message Mobile laser scanning and geometrical analysis revealed relationships between tree geometry and seed dispersal mechanism, latitude of origin, as well as growth. Abstract The structure and dynamics of a forest are defined by the architecture and growth patterns of its individual trees. In turn, tree architecture and growth result from t...

Research on mixed forests has mostly focused on tree growth and productivity, or resistance and resilience in changing climate conditions, but only rarely on the effects of tree species mixing on timber quality. In particular, it is still unclear whether the numerous positive effects of mixed forests on productivity and stability come at the expens...

Trees have a fractal-like branching architecture that determines their structural complexity. We used terrestrial laser scanning technology to study the role of foliage in the structural complexity of urban trees. Forty-five trees of three deciduous species, Gleditsia triacanthos, Quercus macrocarpa, Metasequoia glyptostroboides, were sampled on th...

Short rotation coppices play an important role in providing biomass for energetic use. Mixing fast-growing tree species in short rotation coppices may show complementarity effects and increased yield. The aim of this study was to analyze the effect of species interaction in mixed short rotation coppices with fast-growing Populus spp.-hybrids and th...

In Europe, the non-native Northern red oak (Quercus rubra L.) is widely recommended for future cultivation. However, outside its natural range, Northern red oak has to date been insufficiently studied both in terms of silviculture and genetics. To clarify this, we studied the architecture of 92 (pre-) dominant Northern red oak trees in five German...

Unfortunately, there is information missing in Fig. 3. This figure represents all 4 poplar genotypes and black locust, which are differentiated by the letters (a) to (e).

Northern red oak wood is valuable for a variety of applications not only in its natural distribution range in North America, but also in Europe. Timber quality and stem diameter largely determine timber prices and respective uses. Silvicultural management is key to influencing tree growth and stem quality. In Germany, crop tree thinning is currentl...

The structural complexity of the understory layer of forests or shrub layer vegetation in open shrublands affects many ecosystem functions and services provided by these ecosystems. We investigated how the basal area of the overstory layer, annual and seasonal precipitation, annual mean temperature, as well as light availability affect the structur...

Agroforestry systems provide important ecosystem functions and services. They have the potential to enrich agricultural monocultures in central Europe with structural elements otherwise absent, which is expected to be accompanied by a surplus of ecosystem functions. Here we used quantitative measures derived from terrestrial laser scanning in singl...

Automated species classification from 3D point clouds is still a challenge. It is, however, an important task for laser scanning-based forest inventory, ecosystem models, and to support forest management. Here, we tested the performance of an image classification approach based on convolutional neural networks (CNNs) with the aim to classify 3D poi...

The complexity of forest structures plays a crucial role in regulating forest ecosystem functions and strongly influences biodiversity. Yet, knowledge of the global patterns and determinants of forest structural complexity remains scarce. Using a stand structural complexity index based on terrestrial laser scanning, we quantify the structural compl...

Methodology and Data for New insights into tree architecture from mobile laser scanning and geometry analysis: https://datadryad.org/stash/dataset/doi:10.5061/dryad.2fqz612n6

Light is one of the most critical factors controlling tree survival and growth. Limited light availability induces phenotypic plasticity, thus enabling plants to adapt to suboptimal conditions. The plastic responses are species-specific and are thought to largely depend on species' shade tolerance. This study aims to add to existing research by try...

One of the main goals of modern silviculture is to emulate the structural complexity of old-growth forests. In this context, it is of advantage to identify a target state of structural complexity at the stand level and to analyze the spatial characteristics that led to the desired complexity of forest structures in primary forest references. In thi...

The threedimensional forest structure is an important driver of several ecosystem functions and services. Recent advancements in laser scanning technologies have set the path to measuring structural complexity directly from 3D point clouds. Here, we show that the box-dimension (Db) from fractal analysis, a measure of structural complexity, can be o...

Continuous cover forestry is often considered a management alternative to age-class forestry, in closer compliance with economic as well as societal demands. It is further thought to provide forest stands of high stability and resilience under conditions of climate change. The guiding principle for the stand structure of continuous cover forestry s...

The proportion of mixed-species forests is presently increasing since they are commonly seen as providing a higher level of many ecosystem goods and services than monospecific stands. This may be due to a more complex three-dimensional distribution pattern of plant elements, which has often been noted, but to date rarely been quantified. In the pre...

Modern silviculture is based on simulating natural disturbance regimes on the one side and reducing their impact on the other side. Disturbances modify light regimes of forests along complex spatial patterns, and species participating in the ecosystem tend to have unique adaptations to the multitude of light conditions found in forests. We studied...

Individual tree architecture and the composition of tree species play a vital role for many ecosystem functions and services provided by a forest, such as timber value, habitat diversity, and ecosystem resilience. However, knowledge is limited when it comes to understanding how tree architecture changes in response to competition. Using 3D-laser sc...

Accurate guidelines for silvicultural management of exotic tree species in Germany are sparse. For example, northern red oak (Quercus rubra L.) is the most commonly planted exotic deciduous tree species in Germany, but its response to varying levels of competition intensity has not yet been adequately explored. Here, we used terrestrial laser scann...

The use of natural regeneration techniques is one of the key elements of modern (close-to-nature) forestry. In natural forests, changes in canopy cover, such as the emergence and successive re-closure of canopy gaps are particularly important, as they influence the light availability on the forest floor. Creating canopy gaps of different size is a...

Key message We found structural complexity can best be predicted from a combination of measures that relate to the horizontal and vertical, as well as the internal branching pattern of the trees (range of branch angles). Abstract Forest structure is related to several ecosystem services and functions provided by forests. To support a management fo...

Tree saplings are exposed to a competitive growth environment in which resources are limited and the ability to adapt determines general vitality and specific growth performance. In this study we analyzed the aboveground spatial neighborhood of oak [Quercus petraea (Matt.) Liebl.] and beech (Fagus sylvatica L.) saplings growing in Germany, by using...

Understory vegetation influences several ecosystem services and functions of European beech (Fagussylvatica L.) forests. Despite this knowledge on the importance of understory vegetation, it is still difficult to measure its three-dimensional characteristics in a quantitative manner. With the recent advancements in terrestrial laser scanning (TLS), w...

Functionally, ectomycorrhizal (ECM) and saprotrophic (SAP) fungi belong to different guilds, and they play contrasting roles in forest ecosystem C-cycling. SAP fungi acquire C by degrading the soil organic material, which precipitates massive CO2 release, whereas, as plant symbionts, ECM fungi receive C from plants representing a channel of recentl...

Timber quality is the main driver of timber prices and is strongly influenced by the competition a tree experiences until its day of harvest. Regulating competition is an integral part of silviculture, and therefore, deeper understanding of the competitor’s influence on timber quality is important. Since mixed forest stands and the share of broadle...

The microclimate in forest ecosystems can be altered by modifications of stand structure due to forest management or natural forest development. Current forest management practices in Central Europe and North America aim to promote structural heterogeneity and maintain forest canopy cover, which is known to be a major driver of forest microclimate....

Environmental monitoring and assessment of the extent and change of land uses and their renewable natural resources over time is a key element in many international processes and one crucial basis for sustainable management. Remote sensing plays an increasingly important role in these monitoring systems, especially if the interest is in large areas...

The high structural heterogeneity of primary forests is assumed to positively affect various ecosystem traits and functions, e.g. biodiversity, resilience and adaptability. Against this background, old-growth forest structures are emulated in many managed forests. To properly emulate such structures, quantitative reference values are required, thro...

Deep knowledge of the species-specific response of alien tree species to changes in competition due to silvicultural activities is mostly lacking so far. Based on dendrochronological records (stem disk samples) at various height along the stem, we analyzed the annual volume increment and growth response to changes in competition of seven alien and...

Fulltext Share Link (until December 15, 2018): https://authors.elsevier.com/c/1XybY57Eq07Kxc *** Abstract: Forests are under pressure from accelerating global change. To cope with the multiple challenges related to global change but also to further improve forest management we need a better understanding of (1) the linkages between drivers of ecosy...

The position and size of trees is basic information available for most forest-research sites. Based on such information, various stand structural indices and measures can be calculated that describe the two-dimensional or three-dimensional forest structure. We used fractal analysis to calculate the box-dimension (Db) as a measure of structural comp...

Animal-vehicle collisions (AVCs) pose a serious threat to human and animal welfare, and result in increasing costs for society. Mitigation efforts have been in the focus of research for decades but have revealed only few generalities on where and why AVCs occur. Uncertainty therefore remains on how to make decisions regarding nature conservation, w...

Accurate information on the timber quality of hardwoods is often lacking, in particular for standing trees. In situ measurements of timber quality have the potential to improve the economic yield of a stand and may contribute to the optimal timing of a harvest and, in general, to improving forest management. Here, we used terrestrial laser scanning...

Key message The intensity of silvicultural interventions and the neighborhood composition determine branching patterns, crown shape, and trunk attributes of beech (Fagus sylvaticaL.) trees. Abstract The intensity of silvicultural interventions and the composition of tree species are important forest management decisions. Both determine tree shape...

Measures to describe stand structural complexity efficiently and objectively are increasingly demanded to understand the relationship between forest management, stand structure, biodiversity and ecosystem functioning. Here, we present an approach to quantify stand structural complexity based on fractal dimension derived from single terrestrial lase...

Silvicultural success in achieving, among other management goals, maximum productivity strongly depends on knowledge of the relationship between stand density and the resulting growth response of a stand. However, there are still controversial discussions whether wood production can be enhanced by silvicultural thinning or reaches its maximum in un...

Efficient quantification of the three-dimensional forest structure is of increasing importance for our understanding of forest functions and services, but it remains challenging with conventional methods. We used a single-scan ground-based laser approach in stands with a known difference in management history and associated differences in structure...

The relevance of stand structural heterogeneity for biodiversity conservation is increasingly recognized and efficient tools for its measurement are demanded. Here, we quantified forest structure by calculating the effective number of layers (ENL) for different Hill Numbers (0D, 1D, 2D) as a measure of vertical structure of a subplot. We than use s...

Silvicultural regimes that aim at an increased stand structural diversity typically promote small-scale heterogeneity in horizontal and vertical structures, e.g. through the creation of gaps. We used terrestrial laser scanning (TLS) to investigate impacts of altered growing conditions on trees adjacent to artificial gaps as compared to responses of...

Canopy gaps are an important ecological component in forested landscapes. One limitation to investigating gaps is the lack of efficient, accurate, and objective methods to characterize gap size and shape. This study aimed at investigating various methodologies to overcome this limitation. Six man-made canopy gaps were measured in a coniferous and a...

Agricultural land in the EU is increasingly being used to produce woody crops for energy. The assessment of the stand characteristics of the often densely stocked plantations is laborious and time-consuming. The study presented here focussed on the development of a new and highly efficient method to estimate stand basal area and biomass in such sta...