Estimation of aboveground biomass and net biomass increment in a cool temperate forest on a landscape scale

Abstract

AbstractI clarified aboveground biomass (AGB), net biomass increment (NBI) and its spatial heterogeneity in a cool temperate forest on a landscape scale (>2,200 ha). The relationships among AGB, NBI, and the size frequency distribution of trees of each stand were examined by combining an analysis of vegetation using aerial photographs, and data from 146 inventory plots (28.8 ha in total). This area included natural broad‐leaved stands, harvested broad‐leaved stands, and artificial conifer plantations. A −3/2 power distribution density function was applied to the individual mass frequency distribution of each plot. Estimated AGB in carbon (C) equivalent was 480–5,615 g C m−2 (3,130 g C m−2 on average), and NBI was −98 to 436 g C m−2 year−1 (83.0 g C m−2 year−1 on average). NBI had a single significant relationship with the reciprocal of theoretical maximum individual mass, while NBI was not significantly related to AGB. My results showed that, on a landscape scale, AGB and NBI strongly depend on the size structure of forest stands.