158
cation with drought-tolerant crops. Accordingly, we found the 1:1 arrangement
(maize/pigeonpea)—the common farmer practice—to be less sensitive to site and
year heterogeneity, suggesting greater resilience. Lastly, the use of LERs to quantify
value for the farmer allows the combination of multiple farm outputs and, thus,
provides a way to compare monoculture to polycultures. Our results show mixed
results when describing yield, but clear benefits of intercropped agroforestry in
terms of increased productivity and decreased variance when quantified with LERs
(a more comprehensive measure), highlighting the importance of selecting appropriate indicators when studying CSA.
13.3 Production and Resilience Benefits of Cassava-Based
Intercropping Practices in Tabora
Cassava is the third most important food crop, after maize and rice, in Urambo and
Uyui districts, Tabora region. It is also a more drought-resistant crop than maize and
rice (de Oliveira et al. 2017). Most farmers use this crop as a safety net for food
shortages, especially in years with prolonged drought. At the same time, intercropping has potential to mitigate soil fertility issues. The added biomass to soils under
the cassava-based intercropping system often improves fertility, acidity and soil
structure, especially when leguminous species such as pigeonpea are used (Makumba
et al. 2009). Thus, cassava–legume intercropping was tested as a strategy for diversifying production and/or income sources as well as building biological quality in
these villages.
We evaluated the resilience and productivity aspects of cassava farming under
monoculture, intercropping and rotations with pigeonpea in Mbola, Itebulanda and
Utenge villages. The research followed a mother–baby plot approach (Snapp 2002),
with a researcher-managed plot in each village. Then, ninety farmer-managed plots
(baby plots) were set up across the three villages. There was also an on-station
experiment at the research farm of the Agricultural Research Institute (ARI) in
Tumbi. At the research and mother plots, each treatment was replicated three times
in a randomised complete block design; while treatments at the baby plots were
unreplicated. Measures of yield, soil moisture and RUE were used as indicators of
productivity and resilience. Mitigation was not estimated.
Yields of intercropping treatments (Canavalia, Cowpea and Pigeonpea), by
comparison to the control, were reduced by 78.5%, 58% and 43% respectively in
the research site at the ARI (Table 13.4). The greater reduction in yield in mother
plots provides some indication of the differences between research and farmermanaged implementations of these trials. Similar results were also noted for cassava
yields intercropped with pigeonpea (50%) and cowpea (60%) by farmers in their
baby trial. Such a difference has broad implications for our understanding of the
ability of management practices to generate resilience and livelihood benefits, as the
vast majority of the data available to evaluate the climate-smartness of technologies
was generated on the research stations (Rosenstock et al. this volume). Intercropping
A. A. Kimaro et al.
cation with drought-tolerant crops. Accordingly, we found the 1:1 arrangement
(maize/pigeonpea)—the common farmer practice—to be less sensitive to site and
year heterogeneity, suggesting greater resilience. Lastly, the use of LERs to quantify
value for the farmer allows the combination of multiple farm outputs and, thus,
provides a way to compare monoculture to polycultures. Our results show mixed
results when describing yield, but clear benefits of intercropped agroforestry in
terms of increased productivity and decreased variance when quantified with LERs
(a more comprehensive measure), highlighting the importance of selecting appropriate indicators when studying CSA.
13.3 Production and Resilience Benefits of Cassava-Based
Intercropping Practices in Tabora
Cassava is the third most important food crop, after maize and rice, in Urambo and
Uyui districts, Tabora region. It is also a more drought-resistant crop than maize and
rice (de Oliveira et al. 2017). Most farmers use this crop as a safety net for food
shortages, especially in years with prolonged drought. At the same time, intercropping has potential to mitigate soil fertility issues. The added biomass to soils under
the cassava-based intercropping system often improves fertility, acidity and soil
structure, especially when leguminous species such as pigeonpea are used (Makumba
et al. 2009). Thus, cassava–legume intercropping was tested as a strategy for diversifying production and/or income sources as well as building biological quality in
these villages.
We evaluated the resilience and productivity aspects of cassava farming under
monoculture, intercropping and rotations with pigeonpea in Mbola, Itebulanda and
Utenge villages. The research followed a mother–baby plot approach (Snapp 2002),
with a researcher-managed plot in each village. Then, ninety farmer-managed plots
(baby plots) were set up across the three villages. There was also an on-station
experiment at the research farm of the Agricultural Research Institute (ARI) in
Tumbi. At the research and mother plots, each treatment was replicated three times
in a randomised complete block design; while treatments at the baby plots were
unreplicated. Measures of yield, soil moisture and RUE were used as indicators of
productivity and resilience. Mitigation was not estimated.
Yields of intercropping treatments (Canavalia, Cowpea and Pigeonpea), by
comparison to the control, were reduced by 78.5%, 58% and 43% respectively in
the research site at the ARI (Table 13.4). The greater reduction in yield in mother
plots provides some indication of the differences between research and farmermanaged implementations of these trials. Similar results were also noted for cassava
yields intercropped with pigeonpea (50%) and cowpea (60%) by farmers in their
baby trial. Such a difference has broad implications for our understanding of the
ability of management practices to generate resilience and livelihood benefits, as the
vast majority of the data available to evaluate the climate-smartness of technologies
was generated on the research stations (Rosenstock et al. this volume). Intercropping
A. A. Kimaro et al.