A Novel Modelling Approach for Predicting Forest Growth and Yield under Climate Change

PLoS One. 2015 Jul 14;10(7):e0132066. doi: 10.1371/journal.pone.0132066. eCollection 2015.

Abstract

Global climate is changing due to increasing anthropogenic emissions of greenhouse gases. Forest managers need growth and yield models that can be used to predict future forest dynamics during the transition period of present-day forests under a changing climatic regime. In this study, we developed a forest growth and yield model that can be used to predict individual-tree growth under current and projected future climatic conditions. The model was constructed by integrating historical tree growth records with predictions from an ecological process-based model using neural networks. The new model predicts basal area (BA) and volume growth for individual trees in pure or mixed species forests. For model development, tree-growth data under current climatic conditions were obtained using over 3000 permanent sample plots from the Province of Nova Scotia, Canada. Data to reflect tree growth under a changing climatic regime were projected with JABOWA-3 (an ecological process-based model). Model validation with designated data produced model efficiencies of 0.82 and 0.89 in predicting individual-tree BA and volume growth. Model efficiency is a relative index of model performance, where 1 indicates an ideal fit, while values lower than zero means the predictions are no better than the average of the observations. Overall mean prediction error (BIAS) of basal area and volume growth predictions was nominal (i.e., for BA: -0.0177 cm(2) 5-year(-1) and volume: 0.0008 m(3) 5-year(-1)). Model variability described by root mean squared error (RMSE) in basal area prediction was 40.53 cm(2) 5-year(-1) and 0.0393 m(3) 5-year(-1) in volume prediction. The new modelling approach has potential to reduce uncertainties in growth and yield predictions under different climate change scenarios. This novel approach provides an avenue for forest managers to generate required information for the management of forests in transitional periods of climate change. Artificial intelligence technology has substantial potential in forest modelling.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Climate Change*
  • Forests*
  • Models, Statistical*
  • Neural Networks, Computer
  • Reproducibility of Results

Grants and funding

The financial support to Dr. M. Irfan Ashraf for his doctoral studies at the University of New Brunswick (UNB), Canada was provided by Higher Education Commission of Pakistan. The partial funding for this study was provided by Natural Sciences and Engineering Research Council of Canada (NSERC) to Fan-Rui Meng and Charles P.-A. Bourque. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.