Analysis of regional carbon allocation and carbon trading based on net primary productivity in China

Abstract. Partitioning carbon fluxes is key to understanding the process underlying ecosystem response to change. This study used soil and canopy fluxes with stable isotopes (13C) and radiocarbon (14C) measurements of a 50-year-old dry (i.e., 287 mm of annual precipitation) pine forest to partition the ecosystem’s CO2 flux into gross primary productivity (GPP) and ecosystem respiration (Re) and soil respiration flux into autotrophic (Rsa), heterotrophic (Rh), and inorganic (Ri) components. On an annual scale, GPP and Re were 655 and 488 g C m−2, respectively, with a net primary productivity (NPP) of 276 g C m−2 and carbon-use efficiency (CUE = NPP / GPP) of 0.42. Soil respiration (Rs) made up 60 % of the total ecosystem respiration and was comprised of 24 ± 4 %, 23 ± 4 %, and 13 ± 1 % Rsa, Rh, and Ri, respectively. The contribution of root and microbial respiration to Re increased during high productivity periods, and inorganic sources were more significant components when soil water content was low. Compared to the mean values for 2001–2006 at the same site; (Grünzweig et al., 2009), annual Rs decreased by 27 % to the mean 2016 rates of 0.8 ± 0.1 µmol m−2 s−1). This was associated with decrease in the respiration Q10 values across the same observation by 36 % and 9 % in the wet and dry periods, respectively. Low rates of soil carbon loss combined with relatively high below ground carbon allocation (i.e., 40 % of canopy CO2 uptake) help explain the high soil organic carbon accumulation and the relatively high ecosystem CUE of the dry forest. This was indicative of the higher resilience of the pine forest to climate change and the significant potential for carbon sequestration in these regions.

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Eddy Covariance vs. Biometric Based Estimates of Net Primary Productivity of Pedunculate Oak (Quercus robur L.) Forest in Croatia during Ten Years

Forests ◽

10.3390/f9120764 ◽

2018 ◽

Vol 9 (12) ◽

pp. 764 ◽

Cited By ~ 5

Author(s):

Mislav Anić ◽

Maša Ostrogović Sever ◽

Giorgio Alberti ◽

Ivan Balenović ◽

Elvis Paladinić ◽

...

Keyword(s):

Eddy Covariance ◽

Primary Productivity ◽

Net Primary Productivity ◽

Carbon Allocation ◽

Carbon Sink ◽

Global Radiation ◽

Environmental Drivers ◽

Poor Correlation ◽

Pedunculate Oak ◽

Annual Nee

We analysed 10 years (2008–2017) of continuous eddy covariance (EC) CO2 flux measurements of net ecosystem exchange (NEE) in a young pedunculate oak forest in Croatia. Measured NEE was gap-filled and partitioned into gross primary productivity (GPP) and ecosystem reparation (RECO) using the online tool by Max Planck Institute for Biogeochemistry in Jena, Germany. Annual NEE, GPP, and RECO were correlated with main environmental drivers. Net primary productivity was estimated from EC (NPPEC), as a sum of −NEE and Rh obtained using a constant Rh:RECO ratio, and from independent periodic biometric measurements (NPPBM). For comparing the NPP at the seasonal level, we propose a simple model that aimed at accounting for late-summer and autumn carbon storage in the non-structural carbohydrate pool. Over the study period, Jastrebarsko forest acted as a carbon sink, with an average (±std. dev.) annual NEE of −319 (±94) gC m−2 year−1, GPP of 1594 (±109) gC m−2 year−1, and RECO of 1275 (±94) gC m−2 year−1. Annual NEE showed high inter-annual variability and poor correlation with annual average global radiation, air temperature, and total precipitation, but significant (R2 = 0.501, p = 0.02) correlation with the change in soil water content between May and September. Comparison of annual NPPEC and NPPBM showed a good overall agreement (R2 = 0.463, p = 0.03), although in all years NPPBM was lower than NPPEC, with averages of 680 (±88) gC m−2 year−1 and 819 (±89) gC m−2 year−1, respectively. Lower values of NPPBM indicate that fine roots and grasses contributions to NPP, which were not measured in the study period, could have an important contribution to the overall ecosystem NPP. At a seasonal level, two NPP estimates showed differences in their dynamic, but the application of the proposed model greatly improved the agreement in the second part of the growing season. Further research is needed on the respiration partitioning and mechanisms of carbon allocation.

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Seasonal trends of Amazonian rainforest phenology, net primary productivity, and carbon allocation

Global Biogeochemical Cycles ◽

10.1002/2015gb005270 ◽

2016 ◽

Vol 30 (5) ◽

pp. 700-715 ◽

Cited By ~ 16

Author(s):

Cécile A. J. Girardin ◽

Yadvinder Malhi ◽

Christopher E. Doughty ◽

Daniel B. Metcalfe ◽

Patrick Meir ◽

...

Keyword(s):

Primary Productivity ◽

Net Primary Productivity ◽

Carbon Allocation ◽

Seasonal Trends ◽

Amazonian Rainforest

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Effects of Soil Fertilization on the Allocation of Net Primary Productivity in Tropical Rainforests of Chocó, Colombia

10.20944/preprints202107.0522.v1 ◽

2021 ◽

Author(s):

Harley Quinto-Mosquera ◽

Hamleth Valois-Cuesta ◽

Flavio Moreno-Hurtado

Keyword(s):

Tropical Forests ◽

Primary Productivity ◽

Net Primary Productivity ◽

Carbon Allocation ◽

Permanent Plots ◽

Tropical Rainforests ◽

Soil Fertilization ◽

Nutrient Contents ◽

The World ◽

And Control

Tropical rainforests have the highest rates of net primary productivity (NPP) of the world. Hypotheses about the effect of edaphic nutrient contents, especially the availability of P, propose that they limit NPP of tropical forests or promote the redistribution of its above and belowground components. However, these hypotheses have not been tested experimentally in highly rainy tropical forests. To test such hypotheses, the effects of soil fertilization on the above and belowground NPP were evaluated in forests of two localities of Chocó (Colombia), one of the rainiest regions of the world. Five fertilization treatments (N, P, K, NPK and Control) were applied, and the above and belowground NPP were determined in permanent plots. There were no significant effects of treatments on total NPP; only the application of N significantly increased litter NPP. Additionally, a redistribution of the above and belowground NPP was found with the application of P, which increased the proportion of fine roots and litter, and decreased the woody components of forest NPP. This change of carbon allocation is interpreted as an ecophysiological mechanism to capture additional nutrients in soils with very low content of available P.

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