Effectiveness OF Mulching Under Miraba in Controlling Soil Erosion, Fertility Restoration and Crop Yield in the Usambara Mountains, Tanzania

Abstract

Soil erosion is a major threat to food security in rural areas of Africa. Field experiments were conducted from 2011 to 2014 in Majulai and Migambo villages with contrasting climatic conditions in Usambara Mountains, Tanzania. The aim was to investigate the effectiveness of mulching in reducing soil erosion and restoring soil fertility for productivity of maize (Zea mays) and beans (Phaseolus vulgaris) under miraba, a unique indigenous soil conservation measure in the area. Soil loss was significantly higher (p < 0·05) under miraba sole than under miraba with mulching, for example, 35 versus 20 and 13 versus 8 Mg ha À1 y À1 for Majulai and Migambo villages, respectively, in 2012. Soil fertility status was significantly higher (p < 0·05) under miraba with Tughutu mulching than under miraba sole, for example, 0·35 versus 0·25% total N, 37 versus 22 mg kg À1 P and 0·6 versus 0·2 cmol(+) kg À1 K for the Majulai village; and 0·46 versus 0·38 total N, 17·2 versus 10·2 mg kg À1 P and 0·50 versus 0·2 cmol(+) kg À1 K for the Migambo village. Maize and bean yields (Mg ha À1 ) were significantly higher (p < 0·05) under miraba with Tughutu mulching than under miraba sole, 2·0 versus 1·3 for maize and 0·9 versus 0·8 for beans in Majulai; and 3·8 versus 2·6 for maize and 1·0 versus 0·8 for beans in the Migambo village in 2012. This implies that Tughutu mulching is more effective in improving crop yield than Tithonia, although both could potentially protect the arable land from degradation caused by water erosion under miraba.

Quantifying the impact of land degradation on crop production: the case of Senegal

“…Organic matter that acts as a binding agent and nucleus in the formation of aggregates is the most important component of soil aggregate stability. Therefore, most cultivation techniques aim to optimize the soil organic matter through (zero-)tillage techniques (Costa et al, 2015;Singh et al, 2015), planting of native tree species (Tesfaye et al, 2014), mulching (Mwango et al, 2014), and land use systems (Araya et al, 2010). These activities are not observed in our database but influence the soil organic matter levels at surface and deeper horizons; moreover, the magnitude of variation is also shaped by specific pedogenic processes (Kukal et al, 2014).…”

The immediate effectiveness of barley straw mulch in reducing soil erodibility and surface runoff generation in Mediterranean vineyards

“…This then is a quick and efficient strategy to reduce soil losses and increase infiltration. The straw should also have a positive effect on soil quality as it will improve soil organic matter, soil biological activity and infiltration rates (Brevik, 2009b;Lieskovský and Kenderessy, 2014;Mahmoud and Abd El-Kader, 2015;Mwango et al, 2015).…”

“…Staff of the Soil Erosion and Degradation Research (SEDER) group have been studying soil erosion processes due to agriculture and cooperating with farmers to find possible solutions to soil erosion issues in vineyards, olive groves, and fruit and almond orchards. Among the soil conservation practices that have recently been implemented, mulching has proven to be effective in reducing water and soil loss rates and improving soil condition Cook et al, 2006;García-Orenes et al 2009;Jordán et al, 2010;Mwango et al, 2015;Mulumba and Lal, 2008;Sadeghi et al, 2015a;Tebrügge and Düring, 1999;Winteraeken and Spaan, 2010). According to Jordán et al (2011), mulch is any material, other than soil, placed or left on the soil surface for soil and water management purposes.…”

Effects of soil erosion by water under different tillage treatments on distribution of soil chemical parameters

“…Ploughing performed on slopes can cause intolerable soil loss, especially if it is performed in up-slope and down-slope directions (e.g. Bertola et al 2007;DeLaune & Sij 2012), while no-tillage (NT) preserves soil quality by reducing soil erosion (Lal 2007;Mwango et al 2016), This practice is still not common in Croatian Stagnosols, mostly due to prejudices about soil compaction, low yields and lime and fertilizers mixing under NT. Since the recorded soil erosion is always higher under low density crops, the effects on the environment may be more pronounced (Lal 2006;Pimentel 2006 Gachene et al 1997) show increase of nutrients in soil sediments in addition to non-eroded soil, while others find the opposite.…”