TY - JOUR
T1 - Long-Term Effects of Arable and Tree Cropping Systems on Soil Organic Carbon and Nitrogen Dynamics in a Tropical Agroecological Transition Zone
AU - Obour, Peter Bilson
AU - Bosompem, Ohene Asa
AU - Owusu, Kwadwo
AU - Danso, Eric Oppong
AU - Plauborg, Finn
AU - Arthur, Emmanuel
N1 - Publisher Copyright:
© 2024 John Wiley & Sons Ltd.
PY - 2024
Y1 - 2024
N2 - Continuous cropping can affect soil carbon and nitrogen stocks and litter decomposition, but research on smallholder farms in Africa is limited. This study, conducted from 2020 to 2023 in Ghana's forest-savanna transition zone, examined four cropping systems: continuous maize monocrop (M), maize rotated with legumes (ML), young cashew intercropped with maize or legumes (YCM/L), and mature cashew (MC). The objective was to assess the long-term impact of the cropping systems on soil organic carbon (SOC), nitrogen (N) stocks, and soil organic matter (SOM) decomposition rates using the tea bag protocol. Results showed significant variability in SOC and N stocks across the systems. At a 0–15 cm depth, SOC in the MC and M systems was 160% and 149% higher than in the YCM/L system. At 15–30 cm, SOC in the M and MC systems was 86% and 132% higher than in YCM/L. Soil nitrogen stocks followed a similar trend, with MC and M systems showing 94%–199% higher values than YCM/L at both depths. SOM decomposition rates for green and rooibos tea in the MC and ML systems were statistically similar after 90 days of incubation (p > 0.05). This study, the first to use the tea bag protocol in Ghanaian soils, revealed that mature cashew and sustainable practices, such as adding maize stover, can enhance SOC and N stocks in highly weathered tropical soils. These findings underscore the potential for specific cropping systems to improve soil health on smallholder farms.
AB - Continuous cropping can affect soil carbon and nitrogen stocks and litter decomposition, but research on smallholder farms in Africa is limited. This study, conducted from 2020 to 2023 in Ghana's forest-savanna transition zone, examined four cropping systems: continuous maize monocrop (M), maize rotated with legumes (ML), young cashew intercropped with maize or legumes (YCM/L), and mature cashew (MC). The objective was to assess the long-term impact of the cropping systems on soil organic carbon (SOC), nitrogen (N) stocks, and soil organic matter (SOM) decomposition rates using the tea bag protocol. Results showed significant variability in SOC and N stocks across the systems. At a 0–15 cm depth, SOC in the MC and M systems was 160% and 149% higher than in the YCM/L system. At 15–30 cm, SOC in the M and MC systems was 86% and 132% higher than in YCM/L. Soil nitrogen stocks followed a similar trend, with MC and M systems showing 94%–199% higher values than YCM/L at both depths. SOM decomposition rates for green and rooibos tea in the MC and ML systems were statistically similar after 90 days of incubation (p > 0.05). This study, the first to use the tea bag protocol in Ghanaian soils, revealed that mature cashew and sustainable practices, such as adding maize stover, can enhance SOC and N stocks in highly weathered tropical soils. These findings underscore the potential for specific cropping systems to improve soil health on smallholder farms.
KW - forest-savanna transition zone
KW - Ghana
KW - soil carbon and nitrogen stocks
KW - soil organic matter decomposition
KW - tea bag protocol
UR - http://www.scopus.com/inward/record.url?scp=85205469617&partnerID=8YFLogxK
U2 - 10.1002/ldr.5322
DO - 10.1002/ldr.5322
M3 - Article
AN - SCOPUS:85205469617
SN - 1085-3278
JO - Land Degradation and Development
JF - Land Degradation and Development
ER -