Farmers’ indegenious knowledge of soil fertility Classification and management in omo nada, limu seka And gera districts of jimma zone, south western Ethiopia

Abstract

The study was conducted in Omo Nada, Limu Seka and Gera districts of Jimma Zone, South Western Ethiopia on farmers’ indegenious knowledge of soils. The study was designed to understand farmers’ perception and indegineous knowledge on soils, to characterize and map the dominate soil type, identify fertility indicators using focus group discussions and transect walk with key informat. Furthermore, inerviews were performed to correlate or match scientifically characterized eleven soil profiles. Farmers’ were able to view and map their soils; they use soil color, texture, yield, water holding capacity, topographic position as criteria for characterization, and as indicators of soil fertility and type of crop allocation with input and yield changes over time. The laboratory data revealed that clayey textured soils, silt/clay ratio greater than 0.15 with depth in all profiles and soil bulk density ranges between 1.01g cm-3 to 1.16g cm-3 at the surface to slightly increases with depth in all profiles and higher porosity. The pH of surface soil profiles ranges from moderately acidic to very strongly acid. Low percentage of organic carbon are registered in Omo Nada district Doyo Yaya profiles OND1, OND2, and Limu Seka district Dora LSD and total N contents of the profiles varied from (0.13% to 0.46%) and low in profiles of OND1, OND2 and OND3 and corresponding to lower value of organic matter (2.19%, 2.6%) but higher percentages at surface horizons soils than the subsoil horizons are recorded. The available P contents of the surface soil profiles were higher but in farmers perceived reddish infertile soils profiles OND1, OND2, LSD and Gera district Wanja Kersa profile GWK were medium. Leaching of the some exchangeable cations throughout, surface and subsoil horizon was observed. The cation exchange capacity value greater than 40 meq/100g of soil was observed in profiles of Gurracha/Magala dark red brown soils and less than 38.72 meq/100g of soil was observed in the Dimaa/red soils identified by farmers. The BS greater than 50% in, Omo Nada district Doyo Yaya profile OND3, Nada Bidaru profile ONB1, ONB2, and Gera district Ganji Chala profile GGC1 where farmers identify dominant soil type Dimaa/red and Gurracha/Magalaa dark red brown and fertile soils, and less than 50% were observed in profiles of OND2, LSS1, LSD and GWK at surface soil horizons were indicated that farmers perceived as infertile red soils where as valid with scientific characterization. Hence, the scientific orders the soils studied were Nitisols, Luvisols, Phaeozems, Cambisols and Gleyisols of WRB and Alfisols, Ultisols, Mollisols, and Inceptisols soils based on USDA soil taxonomy, and it correlate with the indigenous knowledge of farmers’ red, dark red brown and grayish soil type respectively. Farmers perceived soil profiles of OND1, LSD, were infertile red soil correlate with the chemical results except profile ONB2 red soil deviated from farmers’ perceptions, LSS2 and ONB1 were moderate fertile dark red and the dark red brown and grayish soil types were perceived as fertile soils correlate with the analyzed scientific procedures. Farmers’ were perceived their soil fertility status and recognized and able to map their soil types that occurs in their PAs, these helps in decision making in soil fertility management, technology transfer and adoption. Therefore, working with indigenous farmers are relevant in soil fertility management and since they are the ultimate decision makers and farming experience of their soils rather than ignoring indigenous knowledge to solve complex problems.