The effects of species-composition-oriented silviculture on timber value and carbon–a stand-level case study in subtropical China

Abstract

Species selection and composition in afforestation affect forest characteristics, which, in turn, affect the quality and quantity of ecosystem services a forest provides to society. Trade-offs and synergies among the various forest goods and services are key issues in multipurpose forest management. In this study, we propose a stand-level integrated analysis framework applying the dynamic forest simulator PICUS v1.5 and techno-economic analysis to assess the effects of a range of species-composition-oriented silvicultural options on timber value and carbon sequestration in subtropical China. The aim is to inform stakeholders on the costs and benefits of the stand-level options. Taking Pinus massoniana and Castanopsis hystrix to represent dominant native conifers and broadleaves, respectively, in subtropical China, five typical silvicultural options were studied: P. massoniana monoculture with normal and high density (stems ha−1); C. hystrix pure stands; and even-aged and uneven-aged mixtures of both species. Results indicate that the uneven-aged mixture performed better in carbon sequestration than the other four options. The even-aged mixture showed better combined benefits of timber production and carbon sequestration and additional advantages in balancing long- and short-term benefits over 50 years. Furthermore, the even-aged mixture had the strongest adaptability to market fluctuations. The uneven-aged mixture performed best economically among the five options in scenarios of future higher timber prices. The results will inform stakeholders about the performance of stand-level silvicultural options with respect to revenues and environmental benefits to society.