Studies on the soil seed bank of prosopis chilensis (molina) stuntz mesquite) at New Halfa Agricultural Scheme

The experiment was carried out at New Halfa Agricultural Scheme (NHAS) to study mesquite soil seed bank and its characteristics. Soil samples were taken from three sites in the scheme; Campo Elwehda, Tafteesh Elmadina and Gantarat Yaseen and one site out the scheme; Elbija Elhadandwa forest. Soil samples were taken per meter square into two depths (0-5) and (5-10) cm in three replications for two seasons, 2005/2006 and 2007/2008. Growing seedlings were counted at Tafteesh Elmadina and Gantarat Yaseen and Campo Elwehda canals and Burgans per one meter square. Animal faeces samples were taken from pathways and corrals in 1 square m. Randomized Complete Block Design (RCBD) with three replications was used. Other samples of pods were taken from canals and trees. The extracted seeds were tested for germination for five weeks. 15 seeds from 20 samples were sown in plastic trays, filled with sand. Completely Randomized Design (CRD) with three replicates was used. Soil seed bank in season 2005/2006 proved that sound seed bank in Campo Elwehda forest was very big in the both depths (0-5) cm and (5-10) cm which achieved 441000 and 109200 seed, respectively. But Tafteesh El Madina was free of seeds in the both depths. But in season 2007/08 results proved the depletion of seed bank in the study areas except Campo El wehda which was achieved 1386 seed/fed in depth (0-5) cm. The mean number of seeds was 35 and 8 seed/ square m in the first and second 5 cm depth, respectively. Animal seed bank of Campo El wehda pathway was found about 51 and 30 seed/ square m can be added from cattle and goats, respectively, while on the contrary crral animals achieved (103, 4692 and 70) seed/ square m of cattle, goats and donkeys, respectively. Results showed the huge seed bank in animal faeces. Also the study showed the intensive numbers of growing seedlings in eradicated areas before autumn at Tafteesh El madina. But eradicated areas after autumn at Gantarat Yaseen was absolutely free of seedlings. In season 2007/2008 Seedling numbers were diminished at Tafteesh El madina and exceeded at Gantarat Yaseen. The highest germination ratio achieved in the control (tree pods) which was 69% followed by the corral donkeys, canal pods, Campo Elwehda cattle and goats and then corral goats and cattle which were 62.8,62.6,61.9,61,58,4 and 51.6) % respectively. But most of seeds of animal faeces were germinated in the first week fastly and in a large amount. From the study, it is concluded that seed bank in soil and animal faeces was very big and concentrated in the first 5 cm depth. That gives a chance for the natural regeneration of mesquite and its dominance in the region; that is attributed to high seed viability and erminability. The study recommended that the following up and eradication of the re-growing seedlings from the agricultural lands and irrigation canals are very important in a period of three years from the eradication date of mature trees of mesquite and protection the scheme from animal