Development of decision support tools for aquaculture: the POND experience

Decision support systems (DSS) are potentially valuable tools for assessing the economic and ecological impacts of alternative decisions on aquacultur e production. In this paper, we discuss the philosophy of design, Functiona l modules and application areas of POND, a decision tool that has been deve loped to allow analysis of pond aquaculture facilities by the use of a comb ination of simulation models and enterprise budgeting. We focus less on the details of POND's internal models, and more on the experiences we have gai ned from going through the process of the designing, developing and using t he POND software. POND was designed and implemented using object-oriented p rogramming principles. The software makes use of a simulation framework to provide much of the generic simulation, data handling, time flow synchroniz ation and communication features necessary for complex model-based DSSs. Ad ditionally, an architecture suitable for representing and manipulating pond aquaculture facilities was developed in order to meet the design specifica tions of POND. This architecture includes a series of mini-databases, a num ber of knowledge-based components ('experts') models of the pond ecosystem, and various decision support features (e.g. assembling alternate managemen t scenarios, economic analysis, and data visualization). A typical POND sim ulation consists of assembling a number of appropriate objects or entities (e.g. multiple ponds and fish lots), their management settings together wit h appropriate experts (e.g. an aquaculture engineer, an aquatic biologist, an economist, etc.), and projecting changes in the facility over time. Our experience with the development of POND and other simulation-based tools in dicates that the object-based approach provides a robust foundation for dev eloping tools which allow code reusability, facilitate maintenance of compl ex software, and enable partition of program development among multiple pro grammars. Experience gained with POND users suggests that there are largely two groups of aquaculture personnel interested in such applications, namel y commercial growers and educators. These two groups have substantially dif ferent interests and needs. Consequently, a single tool such as POND may no t optimally meet the requirements of both groups. Recent development work o n POND, and the need to involve users in the design process of such tools a re discussed. (C) 2000 Elsevier Science B.V. All rights reserved.