Sustainable intensification is a term now much used in discussions around the future of agriculture and food security. Semi-arid tropics have largely remained outside the process of excessive intensification, due to the paucity of water. Rather agricultural intensification was restricted to the smaller fractions of irrigated areas in the vast areas of semi-arid tropics. The present study analyses the sustainability using three different approaches. One, Geospatial analysis, second crop simulation modelling and third an econometric analysis. In Geospatial analysis both spatial and temporal changes in per unit cropped area are captured with more precision and accuracy. Crop simulation models are valuable tools in assessing sustainability of cropping systems. The major components of the model are vegetative and reproductive development, carbon balance, water balance and nitrogen balance. It simulates crop growth and development using a daily time step from sowing to maturity and ultimately predicts yield. In the present study we evaluated eight sustainability indicators, crop yield, water-use efficiency (WUE), the amounts of soil organic carbon (OC) across cycles of the rotation, nitrogen fixing, ‘N’ leaching, Nitrogen-use-efficiency, inorganic ‘N’ in soil at maturity, total ‘N’ uptake at maturity. Sustainability polygons were developed to illustrate the sustainability state of a crop rotations to traditional rotations. To measure sustainability, household survey data collected from designated studies was used to derive indicators of sustainability. A range of sustainability indicators were generated from the survey relating to ecological, economic and social dimensions. The main purpose of this study was to elicit changes across the farming systems and agro-ecological regions and derive conclusions for sustainability across study locations
Low soil fertility and water shortage are major constraints to food production and food security in semi-arid environments. Field experiments were conducted during two growing seasons (2014 and 2015) in Nigeria. The study examined the effects of Phosphorus (P) applications on crop transpiration (ETc) water use efficiency (WUE)and agronomy phosphorus use efficiency (APUE) and sorghum productivity. The experiments were arranged in split plot design with five (5) P-fertilizerlevels(0, 15, 30, 45 and 60 kg P205ha-1) as the main plot and threevarieties (CSR01, ICSV400 and local) as sub-plot in four replications.Results showed significant differences (P<0.05) amongthe P levels and sorghum varieties for grain yield in both locations and seasons. P increased grain yield by 19-39% over control treatment.The highest mean yield of 3156 kg ha-1 at Minjibir and 2929 kg ha-1 at BUK indicate optimum yield was recorded at the 45 kgP205ha-1 application rate and significantly higher than P rates at 0, 15 and 30kgha-1 respectively.Grain yield WUE washighly significantamongP-fertilizer levels and varieties, however, no significant differences between P-fertilizer rates for biomass WUE.P-application increased grain WUE of sorghum by 20-39%, the ICSV400 estimated the mean highest value of 9.3 and 8.6 kg ha-1mm-1 over CSR-01 and local at both locations.The study observed that the application of P could be an effective fertilization strategy to enhance sorghum yield and water use in low-rainfall cropping system and drought prone environment.
Experimental location on Google Maps
This study aims at describing the baseline situation of crop-livestock systems in the semi- arid regions of Zimbabwe. Using quantitative household surveys data and stakeholder workshops, it captures livelihood strategies, community visions, crop and livestock production and marketing, perceptions of risk and uncertainties and farm household typologies. The present data set captures quantitative household data from two districts of Gwanda and Nkayi. At each site multi-stage sampling approach was used. A total of four wards in each district were purposively selected, to include wards close to and far from market centres and in each ward three villages were randomly selected. Household village population across the two districts ranged from 200-300 households. Using random sampling techniques 25-30 households were selected in each village. The sample size (n) for Gwanda is 350 and for Nkayi is331. The overall goal of the project is to identify, test and prove ways to increase agricultural production, improve household food security, alleviate poverty and thereby reduce food aid dependency in rural Zimbabwe through better integrated crop and livestock production and market participation. The project integrates a participatory technology development framework , including baseline diagnostics, stakeholder workshop, systems simulation modeling, technology screening, on farm trials and demonstrations, with value chain analyses that feed into multi-stakeholder platforms for knowledge exchange thereby linking to effective impact pathways.Two districts of Goromonzi and Murehwa are in the semi-humid region and the other two districts of Gwanda and Nkayi are in the semi-arid region of the country.