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Abstract
Planning models that connect natural forests through corridors formed by
industrial forests result in combinatorial mathematical problems that are difficult to solve and demand special techniques. The main objective of this paper is to apply, improve and
evaluate the performance of a heuristic method named R-ratio (NOBRE and RODRIGUEZ,
2005), developed to solve forest planning problems that consider exclusively binary
variables and are formulated as a model Type I harvest scheduling problem (JOHNSON and
SCHEURMAN, 1977 apud CLUTTER et al., 1992, p. 281). The solution’s connectivity
deficit was evaluated by a recursive algorithm based on the Graph Theory and dynamic
programming techniques. A farm of industrial forest that supplies round wood to a pulp
wood company in the State of São Paulo was used as a study case. The method was effective
in creating feasible solutions after a few number of interactions, showing inefficiency only
in the computational time required. The objective function values of the solutions provided
by the heuristic vary from 99.71% to 99.83% of the optimal solution found by a mixed
integer linear programming, with an average of 48 interactions.