Showing papers in "Ecological Modelling in 1992"

TL;DR: The use of ECOPATH II is exemplified through presentation of a model of the Schlei Fjord ecosystem (Western Baltic) through the use of routines for balancing the flow in a steady-state ecosystem from estimation of a missing parameter.

TL;DR: The Kappa statistic as mentioned in this paper is presented as an objective tool for comparing global vegetation maps, which can result from either compilations of observed spatial patterns or from simulations from models that are global in scope.

TL;DR: In this article, the authors present a set of features of an ecological situation that determine the domain of validity of statements about stability, and compile these features into an ecological checklist aimed at making statements on stability complete and more useful as a result.

TL;DR: A modelling approach using currently changing parameters in accordance with a goal function is introduced and can be considered as a translation of Darwin's theory (‘survival of the fittest’) to thermodynamics.

TL;DR: Environs are a model of J. von Uexkull's theory of environment that differs from embodied-energy theory, but is not in conflict with it, and together they provide complementary perspectives on quantifying subjective values from objective flow processes.

TL;DR: Bayesian Monte Carlo (BMC) as mentioned in this paper has been used to quantify errors in water quality models caused by uncertain parameters and provides estimates of parameter uncertainty as a function of observed data on model state variables.

TL;DR: In this article, a geometric approach based on the singular perturbation method can be applied to detect slow-fast limit cycles, where the fast component of the ecosystem is present at significantly high densities only during a fraction of the cycle.

TL;DR: This paper presents some initial results obtained by investigation of the problem of uncertainty in ecological modelling based on the fuzzy logic approach.

TL;DR: In this article, the authors identify a set of elementary principles that can be considered to provide a sufficient basis for a comprehensive theory of complex ecosystems, which emerged from studies of ecosystems by means of mathematical models.

TL;DR: In this article, the potentials and limitations of hierarchy theory for ecosystem theory, ecosystem research, and ecosystem modelling are discussed in relation to the major research scheme of the project "ecosystem research in the Bornhoved Lakes region".

TL;DR: In this paper, a general algorithm is described for estimating average monthly solar radiation in cal cm−2 day−1 received on mountain slopes that uses basic topographic and climatic information for input, i.e., latitude, elevation, slope aspect and orientation, and average monthly data for ambient temperature, relative humidity and total precipitation.

TL;DR: In this article, a simulation model for Californian chaparral is used to compare the projections of vegetation using response functions representing a calculated realized niche and an assumed fundamental niche, and the results show that using the fundamental niche produces more continuous cover, lags in change, and different dominance following climatic change.

TL;DR: In this article, the relation between parameter choice and exergy was found for models of increasing complexity, and the results showed that the exergy is (very) dependent on the parameters that were examined, i.e. growth rates of phytoplankton, bacteria, two zooplankt classes, and fish.

TL;DR: A simple biomass-based energetic model was developed to help explain patterns and to determine the energetic properties of organisms which affect their resource competitive ability and ability to sustain themselves under predation.

TL;DR: The cells that form the basic units of ecosystems are the result of a long evolutionary process from organic soup to protobiont, to protocells and further on to ever more complex cells with very complicated anabolic (synthesizing) and information development processes.

TL;DR: This paper describes the algorithm and its application to the estimation of some well-known microbial kinetics encountered in many applications in ecology and biotechnology through an efficient numerical optimization procedure based on the flexible polyhedron search.

TL;DR: Chmura et al. as mentioned in this paper constructed a dynamic simulation model to study the relationship of accretion to three components of relative sea level rise: compaction, eustatic rise and submergence.

TL;DR: A classification of ecological models into two types is presented:criptive models condense field data into a concise form and can be used for predictions and simulation models are constructed to provide an understanding.

TL;DR: Evaluation of the (relative) satisfaction of each of the basic orientors allows aggregated assessment of system performance and system limitations in a given environment, of coping deficiencies and resulting stress accumulation, of likely behavioral change and structural dynamics.

TL;DR: A working strategy based on a view of systems in terms of hierarchy together with the implementation of a goal function, such as exergy, is proposed.

TL;DR: In this paper, a stochastic model is introduced which provides the temporal and spatial pattern of a Middle European beech forest (Fagus sylvatica ). Starting from a cyclic succession which is known from field observations, the effect of solar radiation on beech trees is modelled in a simple manner.

TL;DR: In this paper, a simple relationship between the community matrix and the corresponding sensitivity matrix, the matrix whose (i,j) element represents the sensitivity in storage of compartment i to an addition of inflow to compartment j, is derived through the consideration of an ecosystem under "press" perturbation experiments.

TL;DR: It is concluded that interactive, object-oriented programming systems constitute a valuable extension of the ecological modeler's toolbox and can be performed with simulation tools allowing for dynamically changing numbers of interacting components.

TL;DR: In this paper, a model of plant growth governed by soil moisture availability and prevailing weather conditions was adapted to account for perenniality, C 4 photosynthesis, intra-seasonal regrowth, and defoliation effects.

TL;DR: In this article, a definition of ecosystems is given which is based on the irreversibility of fluxes, and a steady state of the ecosystem is defined by equal rates of primary production (photosynthesis) and secondary production (respiration, including mineralization).

TL;DR: In this paper, the authors calculated the energy, power and ascendency of two steady-state models, one representing a moderately productive lake and the other representing a highly productive lake, and showed that the three expressions reproduce indices with similar ratios.

TL;DR: In this paper, an ellipsoidal distribution of foliage elements was used to simulate the physical structure of plant canopies to simulate radiation interception, which has a significant impact on the required computation time.

TL;DR: Empirical data on trophic interactions between the aphid predator Metasyrphus corollae, the Aphid parasite Diaeretiella rapae and the aphids Brevicoryne brassicae and Myzus persicae were collected and a skewed curve seemed to express the development of parasitism in the absence of the predator.

TL;DR: It is hypothesized that the internal organization of the pelagic food web promotes an approximately regular distribution of biomass over the range of functional guilds, and this process may be an underlying mechanism for the observed regular size distribution in pelagic ecosystems.

TL;DR: The model predicts forage intake and diet selection of grazing beef cattle by simulating the mechanistic components of grazing behavior and suggests that, when forage availability is limited, intake is limited by rate of intake and grazing time.