摘要
Soil management technologies for climate change adaptation and mitigation are needed to increase and sustain food production in smallholder agriculture while sequestering inert carbon in the soil. In a field studies at Crops Research Institute, Kwadaso-Kumasi Ghana, a control treatment, five inorganic fertilizer combinations （P30K60, N60P30K60, N120P30K60, NlsoP30K60 and N24oP3oK6o） and four biochar rates ＋ inorganic fertilizer （2 t/ha Biochar ＋ N60P30K60, 4 t/ha Biochar ＋ N60P30K60, 6 t/ha Biochar ＋ N6oP3oK6o and 8 t/ha Biochar ＋N6oP3oK6o） were assessed for their effect on soil moisture storage, soil available nitrogen and crop yield. The test crop was okra. Biochar amendments increased soil moisture storage by 14% relative to sole inorganic fertilizer applications. Biochar ＋ inorganic fertilizer relative to sole inorganic fertilizer increased soil available nitrate concentration by 85% at 0-15 cm soil depth but decreased soil ammonium-N by 71%. Compared to control, inorganic fertilizer （P3oK6o） resulted in more than 100% increase in okra fresh fruit yield. Addition of 60 kg N/ha to P3oK6o caused 23% decline in okra fresh fruit yield but showed 60% more okra fresh fruit yield than the control. Inorganic N rates of 120,180 kg N/ha and 240 kg N/ha combined with P3oK6o however caused a decline of 74% in okra fresh fruit yield. Biochar ＋ inorganic fertilizer increased okra fresh fruit yield by 100% compared to sole inorganic fertilizer. Biochar, an inert carbon, combined with inorganic fertilizer has tremendous potential to address food insecurity through soil moisture storage and soil N availability.
