Calibrating and Testing the Forest Vegetation Simulator to Simulate Tree Encroachment and Control Measures for Heathland Restoration in Southern Europe

Abstract

We used the Forest Vegetation Simulator (FVS) to simulate tree encroachment and tree control measures in a continental heathland in Southern Europe, where the goal is the conservation of Calluna vulgaris (L.) Hull.We selected as management target a maximum basal area of 4.6 m 2 ha -1 , corresponding to a minimum Calluna cover of 25%, and modeled stand dynamics along a 50-year period under 3 management scenarios: 1) no management, 2) low-frequency prescribed burning, and 3) low-frequency prescribed burning followed by annual grazing. We initialized and calibrated the Northeastern variant of FVS with data measured in the field, and the Fire and Fuel Extension (FFE) with additional data from a prescribed burning experiment. We carried out most of the calibration by multipliers, including a novel way to simulate the impact of grazing on shoot height and survival. In order to simulate fire behavior, we designed a custom fire behavior fuel model for heath fuels. Successful validation of simulated stand-scale attributes and post-fire mortality was carried out using equivalence testing. Model projections showed that stand basal area would exceed the target threshold under both the no-management and the prescribed burning scenario, 5 and 10 years into the simulation respectively. Conversely, prescribed burning followed by yearly grazing successfully controlled encroaching trees throughout the simulation, by keeping their basal area below the threshold associated to the maintenance of the heathland cultural landscape.

Fire, humans and landscape in the European Alpine region during the Holocene

“…6, left) (Gobet et al, 2003;Ali et al, 2005;Schulze et al, 2007;Genries et al, 2009;Garbarino et al, 2013), as well as the lowland Calluna vulgaris dominated heathlands (Fig. 6, right) with sparse birches and oaks (Borghesio, 2009;Ascoli and Bovio, 2010;Vacchiano et al, 2014b).…”

Harmonized dataset of surface fuels under Alpine, temperate and Mediterranean conditions in Italy. A synthesis supporting fire management

“…This uses a mixed approach with both destructive (i.e., vegetation removed and analyzed in the laboratory) and non-destructive techniques (see next paragraph), such as indirect estimates of fuel loads based on allometry equations (Corona et al 2012, Castagneri et al 2013, Sirca et al 2016, Conti et al 2019. The remaining 35% of survey data adopted protocols that are similar to the ones mentioned, but applied a fully destructive sampling to the shrub component, as they were mostly carried out in shrubland fuelbeds (Bacciu et al 2009, Duce et al 2012, Castagneri et al 2013, Vacchiano et al 2014.…”

“…of Agriculture, University of Sassari, v. Cristoforo Colombo 1, I-08100 Nuoro (Italy); (9) Dept. of Agriculture, Food, Environment and Forestry, University of Florence, v. S. Bonaventura 13, 50145 Firenze (Italy); (10) Direzione Protezione Civile e Polizia locale, Regione Veneto, Marghera, VE (Italy); (11) University of Sassari, Dip.to di Agraria, Sassari (Italy); (12) Fondazione Centro Euro-Mediterraneo sui Cambiamenti Climatici (CMCC) -IAFES Division, Sassari (Italy); (13) Independent researcher, Agricultural High School "Duca degli Abruzzi", v. Merlin 1, Padova (Italy) @ @ Giorgio Vacchiano (gvacchiano@gmail.com) (Salis et al 2013, Vacchiano et al 2014. A quantitative characterization of fuels in Italian forests, shrublands and grasslands is the first step towards developing harmonized fuel datasets to support fire management decisions and calibrating fuel inputs for fire software applications and DSS used by professionals and researchers (Bacciu et al 2009.…”

The rapid climate change-caused dichotomy on subtropical evergreen broad-leaved forest in Yunnan: Reduction in habitat diversity and increase in species diversity

“…Climate change can shape forest structure and function by altering the frequency, intensity, duration, and timing of fire, drought, introduced species, insect and pathogen outbreaks, hurricanes, windstorms, ice storms, and landslides ( Dale et al., 2001 ). Shifts in vegetation distribution in response to past and current climate changes have previously been described ( Peñuelas and Boada, 2003 , Vacchiano et al., 2014 , Guillera-Arroita et al., 2015 ). If current climate trends continue or accelerate, major changes to forest management will become necessary ( Hamann and Wang, 2006 ).…”