Publication Date
1989
Location
Nice France
Description
Animal production from grassland is a complex process involving man as well as animals and plants which interact in a changing environment. The production can be considered as two interacting systems, a management and a production system as shown in Figure I. The manager monitors the production, compares this information with goals and if necessary makes adjustments in inputs in order to achieve the goals. The complexity of this process is of course dependent on the number of controlled factors. Beef production based on purchased young bulls fed entirely on pasture without conservation is, for example, much simpler to manage than e.g. dairy production based on self-replacing herds fed on highly fertilized pasture, conserved herbage and supplementary feeds. The reason why systems based on many input factors become complex is not only because of the number of factors involved, but in particular because the manager continuously monitors the production and uses this information to decide how to allocate inputs. Because uncontrolled factors such as climate may change quite often, management decisions also have to be altered. From a scientific point of view, complex grassland systems reate problems. The systemic approach where the system is
characterized purely through its production at different combinations of inputs has some obvious shortcomings because multifactorial grazing trials are very resource demanding. On the other hand, the analytical-synthetical or mechanistic approach where the behaviour of the systems is explained from the mechanism between the different compartments in the system (France and Thomley, 1984) raises problems: 1) it is difficult to measure the flow from one compartment to another; 2) the relationships which have to be examined increase progressively due to the analytical process (Weinberg, 1975) and 3) the human factor controlling the system is difficult to incorporate. This paper presents a methodology where knowledge about complex grassland system is obtained by a combination of testing systems in practice (system building) and purposive experimental research (system research).
Citation
Kristensen, E S. and Sorensen, J T., "A Methodology for Combining Field Data, Experimental Research and Modelling in the Development of Grassland Systems" (1989). IGC Proceedings (1985-2023). 28.
(URL: https://uknowledge.uky.edu/igc/1989/session11/28)
Included in
Agricultural Science Commons, Agronomy and Crop Sciences Commons, Plant Biology Commons, Plant Pathology Commons, Soil Science Commons, Weed Science Commons
A Methodology for Combining Field Data, Experimental Research and Modelling in the Development of Grassland Systems
Nice France
Animal production from grassland is a complex process involving man as well as animals and plants which interact in a changing environment. The production can be considered as two interacting systems, a management and a production system as shown in Figure I. The manager monitors the production, compares this information with goals and if necessary makes adjustments in inputs in order to achieve the goals. The complexity of this process is of course dependent on the number of controlled factors. Beef production based on purchased young bulls fed entirely on pasture without conservation is, for example, much simpler to manage than e.g. dairy production based on self-replacing herds fed on highly fertilized pasture, conserved herbage and supplementary feeds. The reason why systems based on many input factors become complex is not only because of the number of factors involved, but in particular because the manager continuously monitors the production and uses this information to decide how to allocate inputs. Because uncontrolled factors such as climate may change quite often, management decisions also have to be altered. From a scientific point of view, complex grassland systems reate problems. The systemic approach where the system is
characterized purely through its production at different combinations of inputs has some obvious shortcomings because multifactorial grazing trials are very resource demanding. On the other hand, the analytical-synthetical or mechanistic approach where the behaviour of the systems is explained from the mechanism between the different compartments in the system (France and Thomley, 1984) raises problems: 1) it is difficult to measure the flow from one compartment to another; 2) the relationships which have to be examined increase progressively due to the analytical process (Weinberg, 1975) and 3) the human factor controlling the system is difficult to incorporate. This paper presents a methodology where knowledge about complex grassland system is obtained by a combination of testing systems in practice (system building) and purposive experimental research (system research).
