11 research outputs found
glmGUI v1.0: an R-based graphical user interface and toolbox for GLM (General Lake Model) simulations
Abstract. Numerical modeling provides an opportunity to quantify
the reaction of lakes to alterations in their environment, such as changes
in climate or hydrological conditions. The one-dimensional hydrodynamic
General Lake Model (GLM) is an open-source software and widely used within
the limnological research community. Nevertheless, no interface to
process the input data and run the model and no tools for an automatic
parameter calibration yet exist. Hence, we developed glmGUI, a graphical user
interface (GUI) including a toolbox for an autocalibration, parameter
sensitivity analysis, and several plot options. The tool is provided as a
package for the freely available scientific code language R. The model
parameters can be analyzed and calibrated for the simulation output
variables water temperature and lake level. The glmGUI package is tested for two sites (lake Ammersee, Germany, and lake
Baratz, Italy), distinguishing size, mixing regime, hydrology of the
catchment area (i.e., the number of inflows and their runoff seasonality),
and climatic conditions. A robust simulation of water temperature for both
lakes (Ammersee: RMSE =1.17ââC; Baratz: RMSE
=1.30ââC) is achieved by a quick automatic calibration. The
quality of a water temperature simulation can be assessed immediately by
means of a difference plot provided by glmGUI, which displays the distribution of
the spatial (vertical) and temporal deviations. The calibration of the lake-level simulations of lake Ammersee for multiple hydrological inputs
including also unknown inflows yielded a satisfactory model fit (RMSE =0.20âm). This shows that GLM can also be used to estimate the water balance
of lakes correctly. The tools provided by glmGUI enable a less time-consuming and
simplified parameter optimization within the calibration process. Due to
this, i.e., the free availability and the implementation in a GUI, the presented R
package expands the application of GLM to a broader field of lake modeling
research and even beyond limnological experts
TRY plant trait database â enhanced coverage and open access
Plant traits - the morphological, anatomical, physiological, biochemical and phenological characteristics of plants - determine how plants respond to environmental factors, affect other trophic levels, and influence ecosystem properties and their benefits and detriments to people. Plant trait data thus represent the basis for a vast area of research spanning from evolutionary biology, community and functional ecology, to biodiversity conservation, ecosystem and landscape management, restoration, biogeography and earth system modelling. Since its foundation in 2007, the TRY database of plant traits has grown continuously. It now provides unprecedented data coverage under an open access data policy and is the main plant trait database used by the research community worldwide. Increasingly, the TRY database also supports new frontiers of traitâbased plant research, including the identification of data gaps and the subsequent mobilization or measurement of new data. To support this development, in this article we evaluate the extent of the trait data compiled in TRY and analyse emerging patterns of data coverage and representativeness. Best species coverage is achieved for categorical traits - almost complete coverage for âplant growth formâ. However, most traits relevant for ecology and vegetation modelling are characterized by continuous intraspecific variation and traitâenvironmental relationships. These traits have to be measured on individual plants in their respective environment. Despite unprecedented data coverage, we observe a humbling lack of completeness and representativeness of these continuous traits in many aspects. We, therefore, conclude that reducing data gaps and biases in the TRY database remains a key challenge and requires a coordinated approach to data mobilization and trait measurements. This can only be achieved in collaboration with other initiatives