Estimation of carbon sequestration potential in coconut plantations under different agro-ecological regions and land suitability classes

Abstract

The study estimated the carbon sequestration potential of 25 year old Tall x Tall coconut (Cocos nucifera L. variety typica) plantations under S 2 (highly suitable for coconut) and S 4 (moderately suitable for coconut) soils in wet (WL 3 , high moisture availability), intermediate (IL 1a , moderate moisture availability) and dry (DL 3 , low moisture availability) agro-climatic conditions during May to September 2009. Variation in total carbon stock (plant and soil), total carbon input (measured as Gross Primary Production of coconut, GPP), total carbon output (measured as plant and soil respiration) and net carbon balance of ecosystems were assessed. Eight coconut palms and sample plots per site were used for estimations (two factor factorial with eight replicates). There is a significant agro-ecological region (AER) x land suitability class (LSC) effect on all the components of the carbon balance in a coconut plantation. The total ecosystem carbon stock (B tot-eco ) reduces along a decreasing moisture gradient from WL 3 to DL 3 and decreasing soil fertility gradient from S 2 to S 4 . The GPP and R tot-eco do not show a reduction along a decreasing moisture gradient from WL 3 to DL 3 on S 2 , whilst it shows a reduction from WL 3 to DL 3 on S 4 . The net C balance reduces from WL 3 to DL 3 on S 4 , whilst it does not reduce from WL 3 to DL 3 on S 2 . C stock of the ecosystem varied between 32 and 72 Mg C ha -1 whilst the net carbon balance varied between 0.4 and 1.9 Mg C ha -1 month -1 under different growth conditions. Of the measured components, GPP and maintenance respiration of coconut palms and soil respiration had greater contributions to the overall C balance of the system. This is the first report on carbon sequestration potential in coconut plantations of Sri Lanka.

Carbon Sequestration Potential of Oil Palm Plantations in Southern Philippines

“…Furthermore, considering only the aboveground biomass, a bit similar result was observed in Syahrinudin (2005) for a 10 year old palm plantation in Sumatra, Indonesia (38.94 tC/ha). Moreover, the above result are found to fall within the carbon stock values of coconut plantations in Sri Lanka (37 tC/ha -64 tC/ha) (Ranasinghe and Thimothias 2012).…”

“…Furthermore, oil palms in this study can be considered comparable to coconuts in terms of carbon stock. Carbon stored in coconuts has an average of 22.73 tC/ha based on a study in Sri Lanka (Ranasinghe and Thimothias 2012). However, bamboo plants (Patricio and Dumago 2014), fruit trees (Janiola and Marin 2016) as well as forest trees (Tulod 2015) in general have higher carbon stock than the oil palms in this study.…”

“…In fact, such value is similar only to the soil organic carbon of pineapple plantations (14.72 tC/ha) and banana plantations (18.28 tC/ha) in Bukidnon, Philippines (Patricio 2014). By comparison, coconut plantations tend to have a higher soil organic carbon which is within 28.0 tC/ha -30.3 tC/ha (Ranasinghe and Thimothias 2012;Patricio 2014).…”

“…Previous studies show that the carbon sequestration rate of the oil palm plantations in this study is comparable to some forest plantations in the country (Lasco and Pulhin 2003) though majority of forest plantations may still have a higher carbon sequestration rate. Furthermore, a study in Sri Lanka suggests that oil palms can also have a comparable carbon sequestration rate with coconuts in low country dry zones in Sri Lanka with a rate of 4.8 tC/ha/year (Ranasinghe and Thimothias 2012). At the same time coconuts studied in Leyte, Philippines also has a carbon sequestration rate of 4.78 tC/ha/year (Lasco et al 2002).…”

Major determinants of fruit set and yield fluctuation in coconut (Cocos nucifera L.)

“…Step 2: Dry matter requirement for respiration of individual fruits of different developmental stages (from experiment 2): The dry matter requirement for respiration of fruits of each developmental stage was estimated according to Navarro et al (2008) and Ranasinghe and Thimothias (2012). The total dry matter requirement of a fruit was calculated as the sum of dry matter requirement for potential growth (PGR) and respiration (R) for each stage.…”