Biomass and carbon dynamics of a tropical mountain rain forest in China

Abstract

Biometric inventories for 25 years, from 1983 to 2005, indicated that the Jianfengling tropical mountain rain forest in Hainan, China, was either a source or a modest sink of carbon. Overall, this forest was a small carbon sink with an accumulation rate of (0.56+/-0.22) Mg C ha(-1)yr(-1), integrated from the long-term measurement data of two plots (P9201 and P8302). These findings were similar to those for African and American rain forests ((0.62+/-0.23) Mg C ha(-1)yr(-1)). The carbon density varied between (201.43+/-29.38) Mg C ha(-1) and (229.16+/-39.2) Mg C ha(-1), and averaged (214.17+/-32.42) Mg C ha(-1) for plot P9201. Plot P8302, however, varied between (223.95+/-45.92) Mg C ha(-1) and (254.85+/-48.86) Mg C ha(-1), and averaged (243.35+/-47.64) Mg C ha(-1). Quadratic relationships were found between the strength of carbon sequestration and heavy rainstorms and dry months. Precipitation and evapotranspiration are two major factors controlling carbon sequestration in the tropical mountain rain forest.

Nitrous oxide fluxes from three forest types of the tropical mountain rainforests on Hainan Island, China

“…Based on observations over a 26-year period from 1980 to 2006, the annual mean temperature is 19.8 C, annual mean precipitation is 2449 mm and annual mean relative humidity is 88%. The wet season is from May to October, and the dry season is from November to April; more than 80% of the annual precipitation falls during the wet season (Chen et al, 2010). The annual mean precipitation during our study period, from June 2012 to May 2013, was about 1990 mm.…”

“…The total area of the Jianfengling National Natural Reserve is approximately 470 km 2 ; the mountain rainforests cover approximately 150 km 2 (Chen et al, 2010). This region has a tropical monsoon climate with markedly wet and dry seasons.…”

Soil Carbon Dioxide Fluxes from Three Forest Types of the Tropical Montane Rainforest on Hainan Island, China

“…Rainfalls during the wet season account for over 80 % of the annual total (Bai et al 2014). The montane rainforests cover about 163 km 2 (Chen et al 2010), with several major forest types including pristine and secondary montane rainforest and plantations. In the present study, we chose on an altitude of 800-900 m three experiment sites representing the three typical local forests, namely the pristine montane rainforest (PF), secondary montane rainforest (SF) and Podocarpus imbricatus plantation (PP) (Fig.…”

“…Shifts in tree species composition would likely provoke the difference of soil CO 2 flux (Díaz-Pinés et al 2014;Katayama et al 2009;Osuri et al 2014). From the point of view of ecological system, we considered such difference of soil CO 2 flux was mainly due to the significant differences in environmental conditions including different species composition and biomasses (Chen et al 2010;Li et al 2002), pH, soil temperature, soil moisture, WFPS, and DOC only between SF and PF (Table 2). Although species composition and biomasses were considerably higher in PF and SF than in PP, there were similar environmental factors (Table 2), and no significant difference between PF and PP, SF, and PP (P > 0.05) (Fig.…”

Carbon cycling of Chinese forests: From carbon storage, dynamics to models

“…Chen et al [4] estimated biomass C densities and their changes from 1983 to 2005 in mountain tropical rainforests of Jianfengling in Hainan Island, based on monitoring data from forest permanent plots and biomass allometric relationships. Their results show that biomass ranges from 397.1 to 502.4 t hm −2 , with an average of 453 t hm −2 , and accordingly the biomass carbon density ranges from 201.4 to 254.9 t C hm −2 , with an average of 230.8 t C hm −2 .…”