Browsing by Author "Muriuki, J."

Now showing 1 - 2 of 2
  • Thumbnail Image
    Item
    Dissemination of Integrated Soil Fertility Management Technologies Using Participatory Approaches in the Central Highlands of Kenya
    (Springer Netherlands, 2011-06) Mugendi, Daniel N.; Mugwe, Jayne; Mucheru-Muna, Monicah; Karega, R.; Muriuki, J.; Vanlauwe, B.; Merckx, R.
    Declining soil fertility and productivity is a critical problem facing smallholder farmers in the central highlands of Kenya. A study to improve soil fertility and farm productivity within the smallholder farming systems in the area was carried out from 2003 to 2006. The specific objectives were to identify farming system constraints, evaluate and disseminate potential integrated soil fertility management (ISFM) interventions using participatory approaches, assess achievements and impacts, and document learning experiences emanating from the methodologies used. The participatory approaches used were Participatory Rural Appraisal (PRA), mother–baby approach (with emphasis on demonstration), farmer groups, stakeholders planning meetings, village training workshops, cross-site visits and participatory monitoring and evaluation. The core problems identified were low crop and fodder yields that were caused by erratic rainfall, soil erosion, low soil fertility and small land sizes. There was high participation of farmers in all the partnership activities, and this possibly contributed to the high uptake of the technologies for testing by farmers whereby after only 2 years a total of 970 households were testing the new technologies. Maize yields at the farm level increased by more than 150% following use of the new ISFM interventions and about half of the farmers within the groups planted close to 500 trees propagated in the group nurseries. We recommend that pathways to reach more farmers should concentrate on demonstrations, farmer training grounds, field days and farmer groups and that a policy framework should be put in place to impart appropriate skills in ISFM to the extension workers.
  • Thumbnail Image
    Item
    Using Apsim-Model as A Decision-Support-Tool for Long-Term Integrated-Nitrogen-Management and Maize productivity under Semi-Arid Conditions in Kenya
    (Cambridge University Press, 2015-04) Kisaka, Oscar M.; Mucheru-Muna, M.; Ngetich, F.K.; Mugwe, Jayne; Mugendi, Daniel N.; Mairura, F.; Muriuki, J.
    There is continued decline in per capita agricultural productivity in the drier parts of Kenya’s central highlands. The declines have been linked to low and declining soil fertility, soil water, high atmospheric heat, prolonged dry-spells and erratic rainfall. Integrated soil fertility management (ISFM) technologies have been developed and tested in the region. Despite their significant impacts, high variability in local soils and climate contributes to large variations and inconsistency in research results among replications. Experimentation is expensive and limited to a few years, sites and scenarios. Crop-growth simulation models suitably complement experimental research, to support decision making regarding soil fertility and water management. This study evaluated the performance of the Agricultural Production Systems Simulator (APSIM) model. APSIM was parameterized and calibrated based on a rain-fed randomized complete block trial (2009–2012) at a research station in Machang’a, Embu County. The study further reported on long-term effects of integrated Nitrogen (N) management from organic residues (goat manure, Lantana camara, Tithonia diversifolia and Mucuna pruriens) and their combination with mineral fertilizers in maize production. The model adequately reproduced the observed trends of maize leaf area index (LAI) and yield response to the testNamendments. Long-termsimulations showed that application of 0, 20 and 40 Kg Nha−1 had low inter-seasonal variations (CV = 18–33%) in yields. High yield variability (CV > 56%) was observed in the application of 60 and 80 Kg N ha−1. Application of 40 Kg N ha−1 by combining mineral fertilizer and manure showed 80% chance of harvesting more than 2.5 Mg ha−1 of maize grain yield. Maize stover mulching at 5 and 6 Mg ha−1 with the same N application increased long-term guaranteed grain harvests to 3.5 Mg ha−1. This is when complemented with 90 Kg P ha−1. This integrated N and soil water management is thus recommended. For subsistence farming, low-cost recommendations are geared towards some ‘guaranteed’ yield stability each cropping season. This recommendation underpins low-cost technologies that reduce production risks among small-holder farmers who faced with intermittent financial problems, to improve food security. However, there is need to evaluate and verify that there is a positive balance of primary nutrients such as N, P and K in such a fertility and water management option. Its effects on C:N levels ought to be evaluated as well.