Soil Structure Stability under Different Land Uses in Association with Polyacrylamide Effects

Sustainability

Haruyuki Fujimaki¹  Takayuki Kawai¹  Mitsuru Tsubo¹  AmrakhI. Mamedov¹  Atsushi Tsunekawa¹  Anteneh Wubet²  Temesgen Mulualem²  GuyJ. Levy³  Nigussie Haregeweyn⁴  Birhanu Kebede⁵  Getu Abebe⁵ 

[1] Arid Land Research Center, Faculty of Agriculture, Tottori University, Tottori 668-0001, Japan;College of Agriculture & Environmental Sciences, Bahir Dar University, Bahir Dar P.O. Box 1289, Ethiopia;Institute of Soil, Water and Environmental Sciences, ARO, Rishon LeZion 7505101, Israel;International Platform for Dryland Research and Education, Tottori University, Tottori 668-0001, Japan;The United Graduate School of Agricultural Sciences, Tottori University, Tottori 680-8553, Japan;

关键词: land use;    soil organic carbon;    structure stability;    soil type;    polyacrylamide;    dryland;   

DOI  :  10.3390/su13031407

来源: DOAJ

【 摘 要 】

Soil structural stability is a vital aspect of soil quality and functions, and of maintaining sustainable land management. The objective of this study was to compare the contribution of four long-term land-use systems (crop, bush, grass, and forest) coupled with anionic polyacrylamide (PAM = 0, 25, and 200 mg L⁻¹) application on the structural stability of soils in three watersheds of Ethiopia varying in elevation. Effect of treatments on soil structural stability indices were assessed using the high energy moisture characteristic (HEMC, 0–50 hPa) method, which provides (i) water retention model parameters α and n, and (ii) soil structure index (SI). Soil (watershed), land use and PAM treatments had significant effects on the shape of the water retention curves (α, n) and SI, with diverse changes in the macropore sizes (60–250; >250 μm). Soil organic carbon (SOC) content and SI were strongly related to soil pH, CaCO₃ soil type-clay mineralogy, exchangeable Ca²⁺, and Na⁺ (negatively). The order of soil SI (0.013–0.064 hPa⁻¹) and SOC (1.4–8.1%) by land use was similar (forest > grass > bush > cropland). PAM effect on increasing soil SI (1.2–2.0 times), was inversely related to SOC content, being also pronounced in soils from watersheds of low (Vertisol) and medium (Luvisol) elevation, and the cropland soil from high (Acrisol) elevation. Treating cropland soils with a high PAM rate yielded greater SI (0.028–0.042 hPa⁻¹) than untreated bush- and grassland soils (0.021–0.033 hPa⁻¹). For sustainable management and faster improvement in soil physical quality, soil properties, and land-use history should be considered together with PAM application.

【 授权许可】

Unknown