Wood production is a major service function of timber productive plantation. Timber has been produced both during multiple thinning and the final harvest. Previous studies focused only on Growing Stock Volume (GSV), and the Historical Process-harvested Timber was often overlooked or not estimated.

Dr. GAO Tian at the Secondary Forest Ecology and Management Research Group, Institute of Applied Ecology (IAE) of Chinese Academy of Sciences and co-workers took the larch plantations in Saihan Dam National Forest Park ( where there is over 43,946 ha larch plantations) as an example. Using optic/radar image, researchers combined data from ground survey and historic record in thinning intensity with cutting interval and rotation period, and designed a Management Process-based Timber production (MPT) framework. They assessed the historical timber production in the process of plantation management by parameters taken from random stands: stock volume and age class.

Results showed that during the period from 1962 to 2010, Saihanba Forest Farm had a total timber production of 7.27 million m³ including current stock volume 4.87 and harvested in the history 240 m³, which means about 1/3 timber production has been overlooked in the earlier assessment.

The new idea in the design of MPT framework is a breakthrough to the traditional method in evaluation timber production based only on current stock volume/biomass and resolves a long-term problem of the historical timber produced in the management process.

The study entitled "Timber production assessment of a plantation forest: An integrated framework with field-based inventory, multi-source remote sensing data and forest management history" was published in International Journal of Applied Earth Observation and Geoinformation.

Figure: Spatial patterns of estimated age-classes (a) and GSV (b); Spatial patterns of timber production assessed by the management process–based timber production framework (c). (Image by GAO Tian)