Formalizing agro-ecological knowledge for future-oriented land use studies

<strong><FONT><p>Keywords</strong> : agro-ecological engineering, land use system, modeling, uncertainty, temporal variability, Costa Rica, West Africa.</p></font><strong><font size="5"></strong></font><FONT><p>Identification and ex-ante assessment of alternative land use systems is increasingly important to develop systems that are able to fulfill multiple and possibly conflicting needs of mankind.</p><p>This study contributes to the development of a formalized approach to identify and engineer future-oriented land use systems at the field level enabling the systematic exploration of land use options at farm and regional level. Case study data from the Atlantic zone of Costa Rica and West Africa are used to develop, test and elaborate the required approach, and to implement the approach in two operational tools.</p><p>A generic procedure is presented consisting of three steps: (i) goal-oriented identification and design of land use systems, (ii) quantification of biophysical production possibilities and (iii) identification of the optimal mix of inputs required to realize production possibilities. Typically, this approach addresses the future and explores <em>possible</em> alternatives and not <em>plausible</em> or <em>probable</em> developments. The approach is based on the integration and synthesis of process-based knowledge of physical, chemical, physiological and ecological processes involved, and empirical data and expert knowledge regarding agronomic and livestock relationships using a variety of numerical tools. The procedure allows to efficiently engineer future-oriented land use systems that are consistent with the objectives at stake while no options are excluded in an early phase of development.</p><p>Consequences of various sources of uncertainty, i.e. in process knowledge and data, and in temporal variation, are made explicit for inputs and outputs of engineered land use systems. These analyses enable a better management or reduction of uncertainty through the identification of alternative systems with smaller uncertainty margins, and identification of research aimed at a more complete understanding of involved processes.</p><p>The existing conceptual engineering framework is expanded with an approach that allows taking into account non-equilibrium soil N-conditions. The development of N-dynamics of various crop rotations is made explicit, so that their long-term effects on the productive capacity of land use systems can be accounted for in making decisions.</p><p>Implementation of the approach in two operational tools shows that formalization of agro-ecological knowledge is a means to improve communication among research disciplines, empirical and theoretical research, and stakeholders and researchers. The tools can be used stand-alone and enable the exploration of land use options at farm and regional level.</p></font&gt