Starting from illuminating the role of variability and uncertainty in
agroecological observations and measurements the paper discusses the p
ossibilities of applying neural networks or neural networks in combina
tion with fuzzy techniques in the held of agroecological modelling. Be
cause of the lack of a consistent theoretical background on the one si
de, but the availability of plenty of observations and subjective empi
rical knowledge on the other side, the investigation of many scientifi
c and the management of many practical questions is very data-driven i
n agroecology. Therefore neural networks and other data driven modelli
ng techniques seem to be adequate modelling tools. Two quite different
applications form the main part of the paper: Neural networks for mod
elling development and matter processes in agroecosystems and a combin
ed neural network-fuzzy approach for modelling habitats of plants and
animals (the EMU-NF model family). (C) 1997 Elsevier Science B.V.