Broad-scale biomass observations in vascular plants have supported the existence of Optimal partitioning theory (OPT), but some findings have indicated that variation in biomass allocation may be driven by differences in plant size. The allometric biomass partitioning theory (APT) was developed to predict how plants allocate biomass in leaves, stems, and roots. However, it has also been questioned. 

In China, the country with the fifth-largest forest area worldwide, offer a unique opportunity to examine patterns of biomass allocation across diverse forest ecosystems. In addition, forest characteristics and environmental factors are thought to account for a large proportion of forest carbon stocks. Although large data sets within and across the broad spectrum of vascular plant species have been used to evaluate patterns of standing biomass, quantitative assessments of forest biomass allocation patterns remain central to forest biology and ecology. 

Using forest biomass data from 1022 sites across China, including 110 sites at which performed field measurements from 2011 to 2012, and 912 sites from the national forest inventory data set (2004-2008), researchers from the Institute of Subtropical Agriculture, Chinese Academy of Sciences (ISA) investigated the biogeographic patterns of biomass allocation in leaves, stems, and roots based on a large-scale biomass survey across forest communities in China. 

The researchers found that according to latitude, longitude, and altitude, the distribution patterns of leaf, stem, and root biomass showed a significantly different trends. Besides, they positively and significantly correlated with stand age and mean annual precipitation. "Trade-offs among leaves, stems, and roots varied with forest type and origin and were mainly explained by stand biomass, and biomass allocation was also influenced by forest type, origin, stand age, stand density, mean annual temperature, precipitation, and maximum temperature in the growing season based on the constraints of stand biomass." said the lead researcher Dr ZHANG Hao from ISA. "After stand biomass was accounted for, the residual variation in biomass allocation could be partially explained by stand characteristics and environmental factors, which may aid in quantifying carbon cycling in forest ecosystems and assessing the impacts of climate change on forest carbon dynamics in China." 

This research was supported by the Chinese Academy Sciences Action Plan for the Development of Western China (KZCX2-XB3-10); the Major State Basic Research Development Program of China (2015CB452703); the Strategic Priority Research Program-Climate Change: Carbon Budget and Related Issues of the Chinese Academy of Sciences (XDA05070404 and XDA05050205), the National Natural Science Foundation of China (Nos. 31370485, 31370623, 31400412 and 41471233); the “100 talents program” of the Chinese Academy of Sciences (2060299, Y251101111); the Western Light Program of Talent Cultivation of the Chinese Academy of Sciences, State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources and Guangxi Provincial Program of Distinguished Expert in China. 

The study entitled "Biogeographical patterns of biomass allocation in leaves, stems, and roots in China's forests" has been published in the Volume 5 of Science Reports, details could be found at http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4630587/  

Contact: WANG Kelin 

E-mail: kelin@isa.ac.cn 

Institute of Subtropical Agriculture, Chinese Academy of Sciences