ASSESSMENT OF CARBON STORAGE AND NUTRIENT CONTENTS IN SOME WETLAND SOILS OF THE NORTHEASTERN REGION OF BANGLADESH

Abstract

An investigation was carried out in four designated wetlands to assess soil
organic carbon (SOC) storage and evaluate soil nutrients of the northeastern
Sylhet basin of Bangladesh. SOC storage was the highest in the Nikli wetland
(4.1 Tg), followed by Hakaluki (4.0 Tg), Hail (2.8 Tg) and Balai wetland soils (2.6
Tg) at 100 cm depths. It is found that the total soil C storage across the medium
low land (MLL) and low land (LL) sites covering the four wetlands of the Sylhet
basin is about 13.5Tg. C storage across the MLL and LL sites at 100 cm depths
was estimated about 5.1Tg and 8.4Tg respectively. It is found that SOC storage
was higher in the low land sites in contrast to medium low land sites. The soil
property varies depending on land types, soil depths and spatial distributions.
Among the investigated wetland soils, Hakaluki wetland stored higher amount
of SOC in the deeper soil layers whereas an inverse relationship between soil
depth and SOC storage was noted for rest of the wetlands. It is apprehended that
SOC storage thus gradually lessening in greater magnitude due to climate
change and other anthropogenic reasons. An integrated management approach
should be developed to restore the SOC sink.