Fluxes of CO2 above a sugarcane plantation in Brazil

Abstract

Reis. 2013. Fluxes of CO2 above a sugarcane plantation in Brazil.Contact CEH NORA team at noraceh@ceh.ac.ukThe NERC and CEH trademarks and logos ('the Trademarks') are registered trademarks of NERC in the UK and other countries, and may not be used without the prior written consent of the Trademark owner. Fluxes of CO 2 were measured above a sugarcane plantation using the eddy-covariance 29 method covering two growth cycles, representing the second and third re-growth 30 (ratoons) harvested with stubble burning. The total net ecosystem exchange (NEE) in 31 the first cycle (second ratoon, 393 days long) was -1964±44 g C m -2 ; the gross 32 ecosystem productivity (GEP) was 3612±46 g C m -2 and the ecosystem respiration (R E ) 33was 1648±14 g C m -2 . The NEE and GEP totals in the second cycle (third ratoon, 374 34 days long) decreased 51% and 25%, respectively and R E increased 7%. Accounting for 35 the carbon emitted during biomass burning and the removal of stalks at harvest, net 36 ecosystem carbon balance (NECB) totals were 102±130 g C m -2 and 403±84 g C m -2 in 37 each cycle respectively. Thus the sugarcane agrosystem was approximately carbon 38 neutral in the second ratoon. Yield in stalks fresh weight (SFW) attained the regional 39 average (8.3 kg SFW m -2 ). Although it was a carbon source to the atmosphere, observed 40 productivity (6.2 kg SFW m -2 ) of the third ratoon was 19% lower than the regional 41 average due to the lower water availability observed during the initial 120 days of re-42 growth. However, the overall water use efficiency (WUE) achieved in the first cycle 43

Long-rotation sugarcane in Hawaii sustains high carbon accumulation and radiation use efficiency in 2nd year of growth

“…Furthermore, climate changes, including reduced frequency of trade winds (Garza et al, 2012) and decreased associated precipitation (Norton et al, 2011), and wide-spread adoption of disease resistant cultivars have occurred in Hawaiian sugarcane systems. The impacts of these changes on biomass accumulation and radiation have not been studied Eddy covariance (EC) has been used to make non-destructive, highly temporally-resolved, field-scale observations of sugarcane carbon accumulation and controls on growth in rain-fed systems in Australia (Denmead et al, 2009) and Brazil (Cabral et al, 2013). However, to the best of our knowledge, no EC observations have been reported for either irrigated or Hawaiian sugarcane systems.…”

“…We also note that alternate cropping systems, such as ratooning, have well documented issues with diseases and yield declines (e.g., Gillespie and Teakle, 1989;Viswanathan, 2001;Pankhurst et al, 2003;Johnson and Tyagi, 2010). Finally, Hawaiian sugarcane also has a higher portion of total respiration as heterotrophic respiration (35%) compared to plant (15%) and ratoon (24%) crops in Brazil (Cabral et al, 2013), which might indicate faster respiration of soil carbon pools in Hawaii. This might be due to the usually fast (less than one month) turnaround time between sugarcane burning/ harvest and replanting in Hawaii.…”

“…Ground biomass samples were dry combusted to determine total carbon content (FLASH 2000 NC Analyzer, Thermo Scientific, Pittsburgh, Pennsylvania, USA). To calculate daily and cumulative biomass for radiation use efficiency (RUE) calculations, we first calculated cumulative heterotrophic respiration (Rh) following Cabral et al (2013) by taking the difference in carbon storage between the harvested biomass and cumulative net ecosystem productivity (NEP) in the Windy field. The ratio of cumulative Rh to cumulative total ecosystem respiration (Re) was then used to calculate daily Rh.…”

“…As with other crops, using sugarcane in advanced conversion techniques incentivizes different agronomic qualities (e.g., plant biomass accumulation and enhanced resource use efficiency) versus traditional traits (e.g., maximum sugar yield) (Muchow et al, 1996;Van der Weijde et al, 2013). Growth and efficiency properties that are advantageous for advanced biofuels, such as net biomass accumulation and radiation use efficiency (RUE), have been investigated for sugarcane using micrometeorological (Cabral et al, 2011(Cabral et al, , 2013, remote sensing (Portz et al, 2011), and field trial/biometric approaches (Inman-Bamber et al, 2011).and forest and have been identified as potential source areas for biofuels (Keffer et al, 2006). Recent emergence of potentially large and stable consumers (e.g., the United States Navy) of advanced biofuels in Hawaii, (Closson, 2013;Steiner, 2012) has spurred renewed interest in growing sugarcane and other high biomass grasses.…”

Water vapour and carbon dioxide fluxes in sugarcane grown in megathermal humid climate in Northeastern Brazil

“…In addition to  the highest WUE values were also recorded in partly cloudy sky days (Table 1), since water vapour losses reduced, and  was higher, under cloudiness condition. The WUE values between 11 and 13 mg CO 2 g -1 (H 2 O) -1 were recorded for sugarcane in São Paulo region, Brazil; however, gross CO 2 assimilation was taken into account (Cabral et al, 2013). Overall, and  were 0.015 mg J -1 and 1.756 mg m , respectively, when the rectangular hyperbolic was set between IR f and NEE (Fig.…”