Comparing Farmers' Perception of Soil Fertility Change With Soil Properties and Crop Performance in Beseku, Ethiopia

Abstract

Farmers' perceptions of soil fertility change were compared with observations on soil quality changes and crop performance in soils from a chronosequence representing a range of soil ages since conversion from forest to cropland (0 to 57 years). A majority of the farmers, 92 per cent, had observed a decline in soil fertility on their land. Farmers use crop yield, indicator plants, soil softness and soil colour to judge soil fertility. They identified 11 plants that they used to indicate high soil fertility and four plants that they used to indicate low soil fertility. There was a strong correlation (r = 0·96) between soil organic matter content (loss on ignition) and farmers' ranking of soil fertility based on colour and softness of soil samples from the chronosequence. The biotest experiment with maize showed an exponential decline in biomass production along the chronosequence, confirming the results of farmers' soil fertility ranking. In the biotest, total soil N predicted produced biomass well (r 2 = 0·95), whereas the relationship with soil available P (Olsen) was less obvious. Among the eight analysed plant nutrients in the maize leaves, N content was found to correlate best with biomass production (r 2 = 0·94). We conclude (i) that there is good agreement between farmers' knowledge and scientific indicators of soil fertility and (ii) that the major reason for declining soil fertility in Beseku is the decrease in N mineralization over time. Interventions should focus on supporting farmers to implement a diversified nutrient management strategy that can maintain or increase long-term productivity of the soil.

Precision of farmer-based fertility ratings and soil organic carbon for crop production on a Ferralsol

“…This agrees with findings in Ethiopia that exhibited farmers' ingenuity in predicting soil fertility status based on experiences on crop yields, indicator plants, soil color or even soil softness (Karltun et al, 2013;Tesfahunegn et al, 2013). For this study, positive complementarities between indigenous and scientific knowledge can be considered much more reliable in soil fertility rating to plan for measures to combat land degradation (Tesfahunegn et al, 2011).…”

“…The main ones are (i) use of local farmers' field experiences, with or without the support of experienced neighbors or front-line workers (Payton et al, 2003;Tesfahunegn et al, 2011); (ii) use of GIS technology with infrared spectroscopy for rapid soil analysis (Shepherd et al, 2003); and (iii) use of soil test kits and visual plant deficiency symptoms for rapid fertility assessment (Sanginga and Woomer, 2009). However, simple soil fertility rating using the FFE approach is reportedly most promising in predicting soil productivity (Karltun et al, 2013;Talawar and Rhoades, 1998;Tesfahunegn et al, 2011). The technique is affordable, rapid and simple to use since it is based on community indigenous knowledge (Corbeels et al, 2000;Payton et al, 2003;Schoonmaker Freudenberger, 1994).…”

The State of Soil Degradation in Sub-Saharan Africa: Baselines, Trajectories, and Solutions

“…Still, in some cases, there is good agreement between farmers knowledge and scientific indicators of soil degradation (SOM and maize yields; [97]). There was significant overlap between scientific and local understanding of soil degradation indicators (e.g., crop yield, plant stunting and presence of weeds) in Swaziland and Botswana [41] and Ethiopia [111], however no data on soil properties other than color and texture were collected.…”

Farmers’ soil knowledge, fertility management logic and its linkage with scientifically analyzed soil properties in southern Ethiopia

“…For instance, the absence of local participation and non-recognition of indigenous conservation-oriented land use practices in Ethiopia has been reported among reasons for not achieving the desired objectives of soil conservation efforts (Yeraswork, 1998 cited by [12]). In addition, the poor adoption of fertilizer due to recommendation of the same rate of fertilizer on a blanket basis for entire ' Agro-Ecological Zones' (AEZs) but having different soil types was also reported [3].…”

“…Farmers locally have acquired knowledge from generations of experience and experimentation that fit local conditions since they have been interacting with their soils for long time [12][13][14][15]. Their knowledge can offer many insights to formulate sustainable management of soils [13,16,17].…”