Survey of Soil Seed Bank in Two Secondary Forests in Nnamdi Azikiwe University Awka, Nigeria

摘要

The survey of soil seed bank in two secondary forests in Nnamdi Azikiwe University Awka was conducted through random collection of soil samples on the study areas at different depths, taking records of the time of germination and number of sprouts on the soil and carrying out taxonomic identification of the species of plants that sprout on the soil samples. The result revealed that for the botanical garden study site, 13 species were identified at soil depth of 0-5cm, 9 species were identified at soil depth of 6-10cm while 2 species were identified at soil depth of 11- 15cm. For the law faculty forest site, 12 species were identified at soil depth of 0-5cm, 9 species were identified at 6-10cm while 4 species were identified at soil depth of 11-15 cm. Specifically, 18 species were identified in botanical garden forest while 15 species were identified in law faculty forest sites with seeds of species like Ageratum conyzoides, Sorghum halepense, Phyllantus niruri found at both sites. About half the species identified were found at soil depth of 0-5 cm while slightly above one-third of species identified were found at soil depth of 6-10cm. The Pearson Momentum Correlation of abundance and diversity measures of the study sites revealed that species diversity was significantly and positively correlated with soil depth while the number of species was significantly and negatively correlated with soil dept. Soil seed bank plays an important role in the vegetation restoration process. This study suggested that the soil seed bank would be adequate to enable a functional cover of indigenous vegetation to re-establish after clearing.