Forest landscape planning with textural constraints: How to control the spatial pattern under competing management objectives

Abstract

Abstract

Managing healthy forest ecosystems under competing objectives (such as achieving harvesting vs. biodiversity conservation goals) requires consideration of whether the texture of the landscape approximates the historical or desired textural pattern – for instance, as driven by natural disturbances. Forest management guidelines in the province of Ontario, Canada provide directions for the development of sustainable management plans, including recommendations to manage the spatial texture of mature and old-growth forests to emulate the patterns of theoretical landscapes affected by natural disturbances alone. While spatial texture as a landscape sustainability indicator is central to the provincial forest management guidelines, no solutions exist to control the texture of landscape attributes in the planning models which support timber harvesting. We modified a harvest scheduling problem model I to maintain the texture of mature and old-growth forest patches close to the target texture of a naturally disturbed landscape. Per the guidelines, our approach optimizes the proportional distribution of mature and old-growth stands at a 5000-ha scale, the most common scale of natural disturbances in Ontario’s boreal forests. As a case study, we explored the impact of landscape texture control in the Wabadowgang Noopming Forest, a boreal area within the province’s managed forest. The proposed approach helps achieve more balanced protection of mature and old-growth forest mosaics in landscapes with active forestry but is shown to be combinatorially hard when implemented to directly control landscape texture according to provincial guidelines. Nevertheless, the methodology is generalizable and can be adapted to manage other landscape texture attributes, such as features delineating wildlife habitat, protected areas, biodiversity refugia or other anthropogenic disturbances.