National Workshop Report on Dryland Husbandry in Sudan
"The widely prevalent instability of annual rain input in the semi-desert of Northern Kordofan is reflected in low biomass productivity in poor rainy years. Evident indicators in recovery occur in good rainy years. This study assessed the 1994 good rainy year with respect to impacts on biomass productivity and soil organic matter content in these areas. However, due to factors related to the time when field work was carried out the study could only provide trends and qualitative description of the signals of recovery. Ideally, two visits of land survey must be made: one at approximately 10-12 weeks after the commencement of the rainy season, and the second visit 10-12 weeks after the first visit. The former visit would reflect the peak of the green mantle and vigour, the latter visit signals the beginning of vegetation anti-climax, though it gives information on the magnitude of disturbance and the residual seed bank stored in the soil for future recovery."