Synthesis and analysis of biomass and net primary productivity in Chinese forests

An extant dataset is presented on biomass and net primary productivity (NPP) of 6 forest biomes, including 690 stands from 17 forest types of China.Data on latitude, longitude, elevation, field measurements of stand age, leaf area index (LAI) and total biomass were collected for 29 provinces from forestry inventory data of the Forestry Ministry of China, as well as a wide range of published literature.The individual site-based NPP was estimated from field biomass measurements based on a common methodology.The range of measured LAI, biomass and estimated NPP is from 0.17 to 41.78 m 2 m -2 (mean = 8.94), from 31.14 to 1569.85 t ha -1 (means = 185.41),and from 2.41 to 40.27 t ha -1 yr -1 (mean = 14.4), respectively.Analyses and synthesis between NPP and environmental factors showed that, in eastern China, NPP of forests increases from north to south, whereas NPP of major forests in southern China decreases in relation to longitude from east to west.In mountainous areas, the distribution of NPP is related to elevation.On a regional basis, the NPP of Chinese forests is highly correlated with annual mean temperature and rainfall, as well as the annual potential evapotranspiration, especially on the basis of site-based comparison.Strong positive correlation also existed between NPP and growing degree-days on a 0 °C base and on a 5 °C base.These all indicated that temperature and moisture are the dominant factors controlling the spatial distribution of NPP in China.A site-based comparison between estimated NPP and NPP modelled by the BIOME3 model showed a fair agreement with a linear regression.A higher correlation occurred in the forest-based comparison between estimated and modelled NPP, whereas the highest correlation was found in the plant functional type (PFT)-based comparison.However, there are many limitations in the current data set and methodologies, such as the lack of some components of biomass and NPP, especially with respect to root production.More detailed field measurements and methodologies covering all components of NPP should be addressed in China in the future. biomass measurement / Chinese forests / environmental factors / estimate and comparison of net primary productivity / spatial patternsRésumé -Analyses et synthèse relatives à la biomasse et à la productivité nette primaire dans des forêts chinoises.Ce travail présente un ensemble de données relatives à la productivité nette primaire (NPP) et à la biomasse incluant des mesures pour 690 stations réparties dans 17 types de forêts en Chine.Six biomes forestiers sont représentés.Les données de latitude, longitude, altitude ainsi que les mesures de terrain sur l'âge des peuplements, l'indice de surface foliaire (LAI) et la biomasse totale ont été rassemblées pour 29 provinces à partir de ce qui est disponible dans l'Inventaire forestier du ministère des Forêts chinois et de données contenues dans un grand nombre de publications.La productivité nette primaire (NPP) pour chaque site a été estimée à partir de mesures de terrain sur la biomasse basées sur une méthodologie identique.Les valeurs minimales et maximales sont, respectivement, pour l'indice de surface foliaire Ann.For.