Abstract:
Land uses and soil and water conservation (SWC) structures affect
topsoil moisture and carbon stocks, particularly in the water deficit
semi-arid environment of the northern Ethiopian highlands. This
study was undertaken to assess the effects of land use and SWC
structures on topsoil moisture, biomass, and soil carbon. Soil
moisture was measured manually using gravimetric methods and
theta probes with data loggers. Vegetation was inventoried and
soil samples collected to assess carbon stocks of biomass and soils
of different land uses. Merebmiti catchment had higher average
gravimetric soil moisture content (GSMC; 24%) in wetlands, with
the lowest (13%) in exclosures, whereas Mayleba catchment had
relatively higher GSMC (14%) in exclosures and the lowest (8%) in
rangelands. In both catchments, GSMC was higher at sampling
locations closer to SWC structures than farther away. Merebmiti
had significantly more biomass carbon (28.9 Mg ha−1) than
Mayleba (6.32 Mg C ha−1). Higher soil organic carbon stocks
were found in exclosures (46.1 ± 2.20 Mg ha−1) and wetlands
(62.1 ± 2.9 Mg ha−1) than in frequently cultivated croplands
(24.3 ± 1.4 Mg ha−1). Effective management of land use and
implementation of SWC structures remarkably improves topsoil
moisture content and carbon stocks in these catchments.
