Survival, growth, aboveground biomass, and carbon sequestration of mono and mixed native tree species plantations on the Coromandel Coast of India

Abstract

In India, reforestation programs with native indigenous tree species are a recent activity. Information on experiences comparing mono- and mixed-species plantations is limited. This study aims to estimate growth, aboveground biomass, and carbon sequestration between the mixed-species plantation and mono-species plantation. The growth, survival, height, aboveground biomass, and carbon sequestration of 82 native mixed species plantations were compared with Casuarina equisetifolia an exotic species planted in this region after over a decade (2006–2016). In the mixed species plantation, 7 species showed 100% survival rate and 19 species were not survived after over a decade intervals. While in the mono plantation, C. equisetifolia showed 92% of the survival rate. The growth rate of mixed species when compared to mono plantation, it showed highly significant differences (P < 0:05) values. Simple linear regression between annual girth increment and height produced very strong positive relations (R2 0.759). The aboveground biomass estimated for the mixed native plantation was 8.007 tonnes and the mono plantation Casuarina had 5.585 tonnes. The total carbon stock estimated for the tree plantation in the two plots (both mixed native and mono) was 7.492 tonnes. A positive correlation was observed between the carbon stock and density of the top 10 species which contributed predominantly to the total carbon stock (rs = 0.773, p < 0.05). Plantation of C. equisetifolia seems to be well adapted and had more carbon stocking potential. On the other hand, mixed plantation with indigenous species would contribute more to sustainable management and they provide great shelters for many faunal communities and provide a greater range of ecological goods and ecosystem services than the mono plantations.