Forest ecosystem service delivery under future climate scenarios and adaptation management options: a case study in central Scotland

摘要

Understanding the impact of climate change on the ecosystem services that Scotland's forests provide and identifying how the sector can adapt is of huge economic, social and environmental importance. We examined the impact of future climate projections and six alternative 'adaptation' forest management options on ecosystem service provision in Cowal and Trossachs Forest District in central Scotland. We assessed the ecosystem services of: harvested timber, standing carbon stock, recreation, biodiversity and operations input (as an indicator of employment). We assessed forest tree species diversity under each management option and considered how increasing species diversity affects ecosystem service delivery. The management options were developed in partnership with the District planning foresters and national policy advisors, and were: conversion to: Low Impact Silviculture; productivebroadleaves; native woodland; and three productive forestry options which prioritised i) production, ii) diversity, and iii) priority timber species. The results are applied to the whole forest area, and are examples of how changes in forest policy and management could affect ecosystem service delivery, and are not future predictions.In our case study area, species suitability increased from the baseline climate (1961-1990 average) to the 2030s, and remained higher until the 2060s. This could present an opportunity for increased production if attention is paid to appropriate speciesselection. Wind risk also increased, which will require advanced planning with particular regard to felling age, thinning practices and the location of sites for conversion to LISS, in order to deliver potential benefits. The forest management options had a larger impact on ecosystem service delivery than climate change. The current age structure of the forestalso had a large effect on the trends. However, our models only examine the impacts of gradual climate change, and not impacts from extreme events such as wind storms, nor do they consider pest and disease outbreaks. Changes in management increased species diversity but resulted in reduced harvested timber volume and standing carbon stock, except for where the most productive species were selected. Standing carbon stock increased under Low Impact Silviculture. The benefits of reducing risk through species diversification need to be assessed alongside the likely consequent reductions in timber supply or standing carbon stock.This research provides a first stage towards modelling forest ecosystem service delivery in Scotland. Analysis will be extended to the remainder of the National Forest Estate and private sector to assess the impacts of climate change and adaptation management on the forest sector in Scotland, and provide support to policy and practitioner decision making.