Decision Support Systems

Introduction

Aquaculture planners and managers are increasingly confronted with complex decisions regarding routine operations of culture facilities, effects of such operations on the surrounding environment, and the role of aquaculture production facilities within larger farming systems. Such decision-makers require analytical tools that integrate various components of the knowledge base, and provide capabilities to rapidly examine the economic and environmental consequences of different decisions. These tools, termed decision support systems, integrate knowledge in the form of mathematical models, rule-based (expert) systems, and/or databases into user-friendly software systems focused on developing, analyzing, and optimizing management strategies.

The OSU component of the Data Analysis and Synthesis Team (DAST) has developed a Windows-based software (POND^©) that provides capabilities for simulation modeling and economic analyses of entire pond facilities. POND^© facilitates the exploration of economic, biological, and physico-chemical issues relevant to pond production, planning, and optimization. It also provides a mechanism for synthesizing CRSP work conducted at various sites because the simulation models in the software are based on fundamental principles of pond aquaculture.

The software has been calibrated for a number of international and domestic fish species including Nile tilapia (Oreochromis niloticus), channel catfish (Ictalurus punctatus), common carp (Cyprinus carpio), tambaqui (Colossoma macropomum), and pacu (Piaractus mesopotamicus). Model validation has been accomplished for these species across various production scenarios such as fertilization regimes, feeding levels, and stocking densities. Data from various CRSP sites recorded in the CRSP Central Database have been extensively used in the calibration and validation of the models implemented in POND^©. The OSU-DAST has also collaborated with the Fisheries Department of the FAO to apply the POND^© fish growth and water temperature models in a regional-scale study to assess the potential for inland aquaculture in Latin America.

POND^© is increasingly being used as a tool to supplement education, extension, and training programs both in the US and overseas. Its use has been promoted via the development of training materials and workshops. Distribution of the software occurs primarily from a World Wide Web site maintained by the OSU-DAST, and copies of the software are also available by direct request.

Although POND^© has been used for a variety of applications, further refinement of the simulation models in the software is required to address pond sediment-water column interactions, and the relationships between fish species and natural food availability under polyculture conditions. These issues have important economic and environmental implications for fertilization, feeding, stocking, water use, and effluent discharge decisions that may be arrived at by the use of POND^© models. Besides facility-level model development and application, there is also the need to conduct macro-level systems analysis where pond aquaculture is only one of several interacting components. Studies proposed by the OSU-DAST during the period 1996-1998 focus on further refinement of existing pond dynamics models, their use in assessing the economic viability and sustainability of pond facilities, and systems analysis of pond aquaculture in relation to its biophysical and socioeconomic environment. All the studies will be conducted in the U.S. The overall deliverable will be a revised version of POND^© with supporting documentation.

Collaborating Institutions

Oregon State University

John Bolte

Shree Nath

Auburn University

Joseph Molnar

Food and Agriculture Organization

James Kapetsky

Introduction

Past research by the Oregon State University (OSU) and University of California, Davis (UC Davis) groups of the Data Analysis and Synthesis Team (DAST) of the PD/A CRSP has focused on the development of computerized tools for pond aquaculture systems. Research by the OSU group has led to the development of a Windows-based software (POND^©) that provides capabilities for simulation modeling and economic analyses of entire pond facilities (Bolte et al., 1995; Nath et al., 1995; Fig. 1). POND^© facilitates the exploration of economic, biological, and physico-chemical issues relevant to pond production, planning and optimization. It can also serve as a valuable tool to supplement education, extension and training programs.

The experience of the DAST has been that extant pond facility-level models do not adequately simulate ponds over the long-term because of (a) an incomplete understanding of pond sediment-water column interactions, and (b) limited information about the relationships between fish species and natural food availability in ponds. These issues have important economic and environmental implications for fertilization, feeding, stocking, water use and effluent discharge decisions that may be arrived at by the use of POND^© models. In addition to pond facility-level model development and application, there is the need to conduct macro-level systems analysis where pond aquaculture is only one of several interacting components (Fig. 2). Studies proposed by the OSU-DAST during the period 1996-1998 focus on further refinement of existing pond dynamics models, their use in assessing the economic viability and sustainability of pond facilities, and systems analysis of pond aquaculture in relation to its biophysical and socioeconomic environment. All the studies will be conducted in the U.S. The overall deliverable will be a revised version of POND^© with supporting documentation.

Investigations to be Conducted

A Pond Sediment-Water Column Model for Phosphorus Cycling
Models for Heterotrophic Dynamics and Polyculture Species Interactions in Ponds
Application of POND^© Models for Optimization of Pond Facilities Based on Economic Performance and Environmental Impact Constraints
Macro-Level Agroecological Systems Analysis and Socioeconomics of Pond Aquaculture