Decision Support Systems in Agriculture: Some Successes and a Bright Future - Efficient Decision Support Systems: Practice and Challenges from Current to Future - page 309

Subsequently, it was apparent that in some high rainfall tropical environments the repeated
clearing of land for food crops resulted in exposing bare soil to the intense rainfall. This
could result in damage to the soil status either by leaching and loss of soluble nutrients on
one hand (Dierolf et al., 1997), loss of enriched, surface soil through soil erosion, or both. In
certain environments a more conservation-effective agro-ecosystem may be a perennial
production system that provides regular food production but where the soil surface remains
covered and protected from the typically highly erosive rainfall of humid tropical
environments, such as those of tropical Indonesia.
A meta-level analysis of nutrient management structure and options in perennial cropping
systems suggested that there also was a discernable and distinctive structure in perennial
cropping systems and that the structure included the following: 1) A nursery phase, in
which the seeds of the perennial plant were germinated and young plants begun, 2) An
establishment phase in which the small seedlings were outplanted into the land that would
become a forest, 3) A period of fast growth, and 4) A mature phase, in which production
continued for many years (Figure 3). A review of the literature was assembled considering
the perennial producer peach palm ( Bactris gasipaes , L.) (Deenik et al., 2000).
Fig. 3. A graphic depiction of four stages of particular importance in the management of
nutrients in perennial crops (Deenik et al., 2000).
As in the case of other meta-level analyses of the agricultural systems, numerous gaps were
observed in the available nutrient management in perennial crops when viewed from this
perspective. As a result several studies were undertaken including collaborators, especially
of the University of Costa Rica and the EMBRAPA/Amazon center in Brazil (Ares et al.,
2002a; Ares et al., 2002b; Ares et al., 2003; Yost and Ares, 2007).
6.3.15 Summary
The meta-level assessment of patterns and structure, found so helpful in the development of
ACID4, was quite helpful in the course of developing PDSS. The meta-level analysis of the
knowledge base resulted in numerous improvements in the concepts and content of nutrient
management in the body of knowledge (knowledge-base) surrounding the nutrient
phosphorus in tropical ecosystems. The identified structure (Diagnosis, Prediction,