A flexible statistics web processing service - Added value for information systems for experiment data

Data management in the life sciences has evolved from simple storage of data to complex information systems providing additional functionalities like analysis and visualization capabilities, demanding the integration of statistical tools. In many cases the used statistical tools are hard-coded within the system. That leads to an expensive integration, substitution, or extension of tools because all changes have to be done in program code. Other systems are using generic solutions for tool integration but adapting them to another system is mostly rather extensive work. This paper shows a way to provide statistical functionality over a statistics web service, which can be easily integrated in any information system and set up using XML configuration files. The statistical functionality is extendable by simply adding the description of a new application to a configuration file. The service architecture as well as the data exchange process between client and service and the adding of analysis applications to the underlying service provider are described. Furthermore a practical example demonstrates the functionality of the service

An assessment of forest canopy structure by LiDAR: Derivation and stability of canopy structure parameters across forest management types

Forest canopies are characterized by the composition, organization, and location of aboveground biomass and of open spaces among these components, thus providing a wide range of habitats for other organisms. Canopies are also the interface between biomass and atmosphere, and thus affect the distribution of light, atmospheric turbulence, temperature, and humidity. We used a small footprint scanner with high pulse density for the assessment of the three-dimensional structure of forest canopies and propose a set of simple and interpretable parameters to quantify outer and inner canopy characteristics. This study is based on 1 ha sample plots in Fagus sylvatica L. and Picea abies (L.) Karst. age class and selectively cut forest and on un-managed old growth stands. The spatial resolution of the canopy height model has a large impact on the stability of the parameters. It should be less than 1 m. Laser pulse densities have less impact on parameter stabilities, but do affect the quantification of local conditions when they are less than 5 m-2. The proposed parameters for quantifying canopy structure are (max, min): surface area index (1.2 to 4.1 m2 m-2), canopy surface height (average 4.6 to 25.5 m; maximum 16.7 to 35.8 m), area fraction of north and west facing slopes (north: 0.8 to 20.4%, west: 2.8 to 22.3%), canopy gaps as fraction of surface area (7.5 to 16.1%), crown islands as fraction of surface area (42.9 to 95.9% of surface area), trunk-space height (2.9 to 19.5 m), euphotic zone depth (1.7 to 8.8 m), canopy entropy (2.1 to 3.4 dimensionless) and contrast (3.7 to 225 m2). Only some of these parameters are correlated but the degree of correlation depends on the conditions. The parameters have ecological significance in quantifying the topography of the canopy. There was no consistent pattern of canopy structural parameters related to forest management

Identification of forest management types from ground-based and remotely sensed variables and the effects of forest management on forest structure and composition

Eleven types of forest management were investigated (coniferous and deciduous age-class forest at pole-, young- and old timber stage, continuous cover forest management, selectively cut forest management, farmers’ forest, coppice, coppicewith- standards and unmanaged forest) with respect to ground-based measurements (diameter at breast height, stand density, tree height, wood volume, tree species composition, coarse woody debris, regeneration, deer browsing) and remotely sensed variables by LiDAR (e. g. canopy height, canopy surface area, canopy depth). Wood volume ranged between 320 m3 ha-1 in continuous cover forest and 730 m3 ha-1 in farmers’ forest. Basal area was between 25 m2 ha-1 in deciduous age-class forest and 49 m2 ha-1 in farmers’ forest. Coarse woody debris ranged between 11 m3 ha-1 in selectively cut forest and 39 m3 ha-1 in unmanaged forest. Number of tree species was lowest in the selectively cut forest (1 to 2 tree species per ha) and highest in coppice forest (up to 8 tree species per ha). Density of regeneration was independent of management, but damage due to deer browsing was highest in unmanaged forest reserves and in selectively cut forest, leading to a decline of admixed species. We found that a classification according to management types as based on management plans is not appropriate for scientific studies of relations between forest structure, biodiversity, and management at plot scale. In reality, some management types, such as continuous cover forest, were not sufficiently distinct. The most consistent separation was between longrotation, short-rotation and uneven-aged forests. The remotely sensed variables distinguished forest structures more clearly than ground-based measurements. Nevertheless, structural variables might be rather similar between unrelated management systems and rather dissimilar even within the same management type at plot scales between 500 m2 and 0,64 ha. This study compares forest inventory between management types and documents the importance of including forest-management and forest structure in the evaluation of the climate mitigation potential of forests and of strategies for preservation of biodiversity

Moving in three dimensions: effects of structural complexity on occurrence and activity of insectivorous bats in managed forest stands

1. Forest management determines to a large degree the three-dimensional arrangement of the vegetation in production forest systems and hence has an essential influence on habitat quality for wildlife. We investigated the effects of forest structure on occurrence, activity and species composition of European bats, an ecologically important group of vertebrates known to be affected by the physical clutter of vegetation. 2. Species composition and activity of bats were assessed with acoustic monitoring on 50 one-hectare experimental plots in a biosphere reserve in Germany. Three-dimensional forest structure was assessed by Light Detection and Ranging (LiDAR), and a set of 20 mathematically derived and fine-grained structural parameters with a minimum of collinearity was used for a quantitative description of the vegetation structure. 3. Occurrence and activity of bats were positively associated with the structural parameters canopy height, standard deviation of the canopy surface roughness and edge fraction, indicating older forest stands with patches of different vegetation heights. In addition, species composition in differently managed forest stands was significantly influenced by the relative proportion of structural parameters. Species of one functional group, sharing similar adaptations in wing morphology and foraging strategy, showed similar associations with three-dimensional structural parameters. In addition, we found species-specific structural parameter associations explaining the occurrence and activity levels of individual species in differently managed production forest types. 4. Synthesis and applications. High-resolution LiDAR data are an important tool to assess structural habitat suitability for bat species. Our data revealed that bat occurrence and activity increases with structural heterogeneity in managed forest stands. Given, that bats provide an essential ecosystem service through top-down control of herbivorous insects, increasing stand structural heterogeneity through management practices (e. g. selective harvesting) is a very effective strategy to assure vital ecosystem functioning in production forest systems

Diverse or uniform? Intercomparison of two major German project databases for interdisciplinary collaborative functional biodiversity research

Research on biodiversity, its relation to ecosystem functioning and services, and the assessment of the impacts of environmental change on biodiversity needs an interdisciplinary perspective. This implies a great diversity of data and data formats gathered mostly in short- to mid-term collaborative research projects. It has been common practice that projects develop specific data management and communication solutions. We compare solutions of two major German collaborative research programs in functional biodiversity research to derive functional commonalities. This in-depth analysis follows five categories of the data life cycle: (i) data acquisition, (ii) metadata management, (iii) database, (iv) exploration, analysis and visualization, and (v) data curation and preservation. The results show that even though both systems were developed completely independently, they reveal comparable overall features and a similar state of implementation. Major focus areas lie in the implementation of comparable metadata schemas and their importance for storage and access strategies for tabular data on the value level. Basic analysis tools and similar management functions are considered. Intensive communication with the users and the orientation of ongoing developments based on user requirements is also important. Both systems are different mostly in specific details which, however, do not influence the overall comparable performance. It should be also emphasized that the same functionality is achieved with completely different software. The choice of software is based on the evaluation of available technologies. Thereby it might be influenced by individual experiences of the developers, but is mainly determined by the data diversity, which forces the usage of flexible technologies to develop adaptable systems. It is concluded that overall features for project databases of collaborative research projects must be supplemented by sophisticated data description, storage, and analysis structures to serve the requirements of integrative functional biodiversity research. (C) 2011 Elsevier B.V. All rights reserved