Assessment the effect of traditional gold mining activities on soil seed bank at al-sobag area of butana rangeland-gad arif state-sudan

Traditional gold mining is one of most human activities practiced at Al-Sobag area of Butana rangeland. Two range sites were selected, one of them near mining area (site A) and the other far from the mining area (site B) represent the unaffected areas. The sample distributed systematically along four lines transects. About 24 soil samples were taken from the two sites to assess seed bank, each sample collected from three depths (0-5, 5-10 and10- 15 cm). All sample of the same depth were mixed of sub-sample of weight 250-g was for seed extraction. All data were analyzed using the Duncan procedure, SAS statistical program. The affected range site by gold mining activities was recorded the same percentage of live and dead seeds (50%), while the unaffected range site was recorded (31.6%) and (68.4%) for live and dead seeds respectively. It observed that the mean of dead seeds in both range sites was more than (50%) of the total seed bank. Also the study revealed the higher species compositions of live seeds in upper soil layer were Indigoferaochstetteri, recorded (36.3%). While the higher species compositions at unaffected range site were Chloris virgate (27.3%). The misuses of rangeland of like traditional gold mining and over grazing may increase soil erosion and loosed upper layer of soil and attributed to decrease the live seed percentage.