Soil Organic Carbon in Forest and Other Land Use Types at Bengkulu City, Indonesia

Wiryono Wiryono,H Aningtias,Z Muktamar,P M Anugrah,S Nurliana,Deselina Deselina

doi:10.7226/jtfm.27.3.184

Abstract

Conversion of natural forest into agricultural land uses has decreased soil organic carbon (SOC) and increased carbon emission into the atmosphere, but proper management of agricultural land can sequester carbon from the atmosphere and increase the SOC. This study was conducted to estimate the SOC content and storage in a forest, agroforestry land, oil palm plantation, and agricultural experimental field and to analyze the correlation between the SOC and other soil characteristics at Bengkulu City, Indonesia. Soil were sampled from the following depths: 0–10 cm, 10–20 cm, and 20–30 cm. The biomass of litter and ground cover was also sampled. This study found that the forest had the highest average SOC content from the three depths, and 0–30 cm depth SOC storage, while the agroforestry system had the lowest of both SOC content and storage. The 0–10 cm depth had the highest SOC content and storage, while the 20–30 cm depth had the lowest of both variables. The SOC was positively correlated with litter biomass, field capacity, exchangeable potassium, cation exchange capacity, and negatively correlated with bulk density and exchangeable calcium, but not correlated with total nitrogen and available phosphorus. High litter biomass input is the key to the maintenance of high SOC.

Highlights

A natural forest has a higher capability of storing carbon both in the soil and above ground than most other land uses (Ravindranath & Ostwald, 2008)
When a forest is converted to other land uses, the soil organic carbon (SOC) decreases while carbon emission into the atmosphere increases (Lal, 2020)
Study sites This research was conducted in four land use types, i.e., urban forest, agroforestry land, oil palm plantations, and agricultural experimental field at Bengkulu City, Bengkulu Province, Indonesia (Figure 1 and Figure 2) from July to September 2020

Summary

Introduction

A natural forest has a higher capability of storing carbon both in the soil and above ground than most other land uses (Ravindranath & Ostwald, 2008). When a forest is converted to other land uses, the soil organic carbon (SOC) decreases while carbon emission into the atmosphere increases (Lal, 2020). To prevent the SOC from being lost and released into the atmosphere, the most popular method is reducing deforestation and forest degradation. In Indonesia, much of the natural forest has been converted into plantations, mostly oil palm plantations (Khasanah et al, 2015). Another method of preventing carbon loss into the atmosphere is improving soil management because the SOC is larger than other carbon pools in the carbon cycle (Deng et al, 2016). The management of soil has no effect on the SOC below 30 cm depth (Franzluebbers, 2021)

Methods

Results

Conclusion