Estimation of Carbon Reserves in Agroforestry Systems in the East Rinjani KPH Forestry Partnership Scheme

Abstract

Forests play a critical role in absorbing atmospheric carbon dioxide (CO₂) and serve as major carbon sinks. This study aims to analyze vegetation species biodiversity, estimate carbon stocks, and determine the relationship between carbon stocks, plant density, and biodiversity. A quantitative and descriptive research approach was employed, utilizing observation and survey techniques. Respondents were selected using Slovin’s formula with a 15% margin of error, resulting in a total sample of 30 farmers. The number of sample plots was determined using a census approach, based on the number of respondents. The average carbon stock in the Mekarsari Village area, under the East Rinjani Forest Management Unit (KPH) Partnership Scheme, was found to be 39.29 tonnes/ha, measured across three vegetation strata: trees, poles, and saplings. Specifically, carbon stocks were 30.93 tonnes/ha at the tree level, 6.08 tonnes/ha at the pole level, and 2.28 tonnes/ha at the sapling level. Regression analysis showed that plant density accounted for only 0.57% of the variation in carbon stocks, whereas the biodiversity index explained 54.57% of the variation. A total of 23 plant species were identified in the agroforestry plots. These results indicate that carbon stock levels in land use systems are significantly influenced by biodiversity and, to a lesser extent, by plant density. Higher biodiversity and plant density contribute to increased carbon sequestration, thereby enhancing overall carbon stocks.