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Item EFFECT OF CONSERVATION AGRICULTURE AND BIOCHAR ON NITROGEN CYCLING IN PIGEON PEA-MAIZE ROTATION ON FERRALSOL IN GULU(Gulu University, 2026-10) OPIYO, WOKORACH SAMUELLow soil fertility is a global challenge frustrating efforts of enhancing crop productivity. One of the most important plant nutrients often in short supply is nitrogen (N). Crops commonly suffer from N deficiency due to high N lost as nitrous oxide (N2O) gas, low nutrient absorption and accumulation in plant. Farmers who use conservation practices such as use of leaf litter to improve soil fertility suffer poor timing of application or slow mineralization process. Thus, objectives of the study were (i) to determine the effect of conservation agriculture (CA) planting basin, biochar and pigeon pea leaf litter on N2O emission, (ii) to determine the effect of CA planting basin and biochar on the quantity and quality of pigeon pea leaf litter, (iii) to determine the effect of variation of nutrient content of pigeon pea leaf litter on mineralization. For objective 1, field experiment consisting of four treatments; CA + biochar, CA + biochar + leaf litter, CA + leaf litters and control. The experiment was organized in completely randomized design with four replicates to determine effect on N2O emission. There was N2O emission of 10–40 µg N2O-N m⁻² h⁻¹ on average across different conservation agriculture practices that did not differ significantly (p=0.137). For objective 2, an experimental design of randomized complete block design was established to test the effect of conservation agriculture, conservation agriculture plus single application of 4 t/ha biochar, conservation agriculture plus double application of biochar at 2 t/ha followed by 1 t/ha and conventional farming on quantity and quality of leaf litters of pigeon pea. Before treatment, quantity of litter and N content on average was 240 kg/ha and 40 g/kg respectively. However, there was no significant effect of treatments on quantity of leaf litters and amount of N in leaf litters. However, leaf P and K content was affected by treatments. Leaf litter from conservation agriculture and conventional practice had lower content of P and K at 2.7 mg/kg and 39 mg/kg, respectively (p<0.001). The P and K content of litter from conservation agriculture with single and double application of biochar was higher at ~3.9 mg/kg and ~62 mg/kg, respectively. For objective 3, incubation experiment on N mineralization rate of leaf litter from different soil nutrient content was conducted over 14-16-day period. Furthermore, the leaf litter significantly stimulates soil microbial activity, with peak CO₂ evolution occurring at day 12 (p < 0.001). This indicates that most active microbial activity is confined to the initial two weeks of application of the litter. Last, ammonium concentrations peaked at day 12 and then dropped sharply as nitrate levels surged between days 13 and 16 (p < 0.001), confirming the typical mineralization-nitrification sequence, with significant result. This study demonstrates that integrating CA with biochar enhances nutrient retention and availability. Furthermore, understanding variation in the nutrient content of the organic litter is important in planning its application to allow time for mineralization. Thus, mainstreaming pigeon pea as part of soil management will be alternative approach that boosts soil health, nutrient level and productivity of soil.Item EFFECT OF CLIMATE-SMART AGRICULTURAL PRACTICES ON SOIL ORGANIC CARBON AND YIELD OF PIGEON PEA IN NORTHERN UGANDA(Gulu University, 2026-10) ABER, CINDERELLAThe current decrease in crop yield has elevated food insecurity with over a billion people affected across the globe and has been attributed to climate change and poor soil quality. This challenge is more pronounced in the developing countries with devastating economic constraints, which deprive people of food security. As such, better and sustainable interventions that improve the soil and contribute to climate change adaptation and mitigation for enhanced yield is needed. A two-season experiment was conducted at Gulu aiming at exploring the effect of conservation agriculture (CA) and biochar on soil carbon, greenhouse gas emission and grain yield of pigeon pea. The experiment followed Randomized Complete Block Design (RCBD) with four treatments replicated four times. The treatments included (i) CA with maize – pigeon pea rotation (CA+PP), (ii) CA with one time biochar application (4 tons/ha) and maize – pigeon pea rotation (CA+BC+PP), (iii) conventional agriculture with maize – pigeon pea rotation (Conv+PP), (iv) CA with half biochar (2t, 1t & 1t/ha per year) and maize – pigeon pea rotation (CA+BC+BC+PP), (v) conventional agriculture with maize monocropping (Conv+MM). The results from experiment showed that CA and biochar improved total soil organic carbon and readily oxidizable carbon and as well as increasing the biomass and grain yield of pigeon pea. The highest total soil organic carbon content of 1.6 – 1.99% and readily oxidizable carbon of 0.05 – 0.059% were recorded in CA+BC+PP compared to total soil organic carbon of 1.5 – 1.53% and readily oxidizable carbon 0.03 - 0.05% in conventional practice. Similarly, a reduction in CO2 emission from 294 to 218 mg CO2-C m-2h-1 and CH4 emission from 63.4 to 21.8 µg CH4-C m-2h-1 was registered in the treatments having climate smart agriculture practices. The biomass at harvest was highest at 13.69 tons/ha in CA+BC+PP in season 1 compared to that of conventional plot of 8.75 tons/ha with corresponding grains yield of 2.11 tons/ha and 1.76 tons/ha, respectively. This pattern of biomass and grain yield between the two treatments was also registered in the second growing cycle though with an overall lower yield. Therefore, CA and biochar can contribute to food security by increasing yield and climate change mitigation through soil C sequestration and reduced greenhouse gas emission. As such, CA practices and biochar application can be considered as sustainable and can contribute to climate resilience.Item DRIVERS OF COPING STRATEGIES TOWARDS EXTREME WEATHER INDUCED HOUSEHOLD FOOD INSECURITY IN ACHOLI SUB REGION OF NORTHERN UGANDA: CASE OF GULU DISTRICT(Gulu University, 2023) OBWONYA GEORGE , MATHEWFood insecurity exacerbated by extreme weather is a global hindrance to achieving the sustainable development goals of ending hunger by 2030 at all levels from global. regional. national and household levels. Evidence has shown that extreme weather events in Uganda have caused crop failure. human and animal mortality. With Uganda's hunger increasing from 26.4°/o in 2016 to · 31 :!~ .. o in 201 R. the prevalence of food insecurity has remained a major concern in the country.The trend insecurity situations have raised questions on the effectiveness of the coping strategies used among the households in Gulu district. This study detennined the status of food security among households: assessed the household coping strategies: and detenninants of choice of coping strategies to extreme weather induced food insecurity in Gulu district. Using a multistage sampling method. a cross Sectional study survey of :!04 participants who are engaged in fanning was conducted. Descriptive statistics. coping strategy index and multiple linear regression were used to analyzed the data. Result revealed that majority (6.5 .59°/o) of the households were severely food insecure. As a result. households employed diverse coping strategies as a way of overcoming weather induced household food insecurity. The coping strategics commonly used among the households included feeding on less expensive foods. reduction on food consumption and expenses. reduction on number of meals per day. children being fed first. skipping meals at times. Furthermore regression analysis showed that some socio-demographic factors such as education (p< 0.018). employment status (p< 0.010). monthly income (p< 0.003). and livestyle~k (p< 0.020), and distance to the market (p< 0.003). influenced household choice of coping strategy. The study finding demonstrates that households relied on food smoothing coping strategies more than other mechanisms and that some social demographic factors influence the coping strategies among households. Therefore. to change the trend. future investigationstions should focus on the aforementioned factors to strengthen the capacity of households through diversification rather than specialiution. public education and awareness. strong local policy implementation and safe guarding of food security crops from totally being subjected to market demand.