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NIBIOs ansatte publiserer flere hundre vitenskapelige artikler og forskningsrapporter hvert år. Her finner du referanser og lenker til publikasjoner og andre forsknings- og formidlingsaktiviteter. Samlingen oppdateres løpende med både nytt og historisk materiale. For mer informasjon om NIBIOs publikasjoner, besøk NIBIOs bibliotek.

2004

Sammendrag

First the scientific method is graphically presented and interpreted in the following manner: `The test of a model is not considered merely as a test of the hypotheses, constructed mathematically, but it is also considered an explicit test of the definition of the quantitative parameters and the measuring systems of the input parameters as well". The representativeness of the input parameters to a specific model as well as the representativeness of the measured parameter values of the testing systems is considered crucial. The concept of representativeness of measured quantitative parameters is therefore outlined for further discussion and practical use in models. Furthermore the idea of differentiating the parameter definitions of the parameters of a model and the parameter definitions of a system for making measurements is presented. This notation is connected to the concept of `representativeness". The status of the system of equations of a model and the scope of such a system is discussed in the following manner: Prognostic system of equations is not interpreted as `governing" physical or biological phenomena, but `the definition of the quantitative parameters", `the system for making measurements" and the `equations" is considered a unit possible to test and use operationally. Thus the ideas of scale and representativeness are not considered separate from the system of equations.

Sammendrag

Major driving forces among companies in the forest products industry are mergers and acquisitions and narrowing the strategic focus to core competencies. The combined effect is that the mutual dependency in customer-supplier relationships increases, and that the share of the total value added provided by each actor decreases. Standard techniques for process mapping are intended as the first step in process improvement. Order processes, extending from identification of demand to fulfilment of demand, commonly cross company borders. The result is an increasing need for inter-company coordination to increase efficiency of material flows. This paper presents preliminary results from the mapping of the order process between a Norwegian retail chain and its major supplier of solid wood products. A model intended for supply chain mapping has been modified and applied to this particular case. One outcome of the mapping is that a detailed overview of the process can reveal simple solutions for process improvement, as individual actors rarely focus on optimising their combined process, but rather have an internal focus. The mapping also provides a basis for evaluation of existing performance measurements, and for development of new measurements with a focus on improving the actors’ combined order process.

Sammendrag

We analyzed berry production in rowan, Sorbus aucuparia L., in southern Norway and examined the ramifying effects of rowan masting on the dynamics of the dominant seed predator and its parasitoid. The apple fruit moth, Argyresthia conjugella Zeller, is a pre-dispersal seed predator of rowan. The larva of the apple fruit moth rely on rowan berries, which in turn is attacked by the parasitoid wasp, Microgaster politus Marsh. We found classic masting in rowan: berry production varied across years (the mean coefficient of variation = 1.02) and was spatially synchronized at large scale (the averaged correlation coefficient = 0.67). Berry production represented a two-year cycle in western but a three-year cycle in eastern Norway. The abundance of the moth and the parasitoid also varied across years and were spatially synchronized. The degree of spatial synchrony decreased and cyclicity became obscure with increasing trophic level. We attempted to assess two different components to the predator satiation, functional and numerical satiations, based on a simple population dynamics model. The observed pattern of seed predation testified that both of functional and numerical satiations were at work in this system. In a comparison at different locations, rowan trees with more variable berry production were more effective in reducing losses to the seed predator. The parasitoids also seemed to experience satiation through the fluctuation in their host abundance. These results show that rowan masting has an adaptive foundation, which impacts the dynamics of higher trophic levels.