Seed bank of the soil in recovery area with different agricultural history

Abstract

The objective of this study was to evaluate the seed bank of the soil with and without the presence of the superficial litterfall on two altitudinal peaks, in an area undergoing recovery, with a history of use and agricultural management, after one year of the site recovery process. Between the end of 2014 and the beginning of 2015, the first activities for the recovery of the site were carried out, such as the fencing of the area and the effective planting of native seedlings. In 2016, 20 soil samples were randomly collected, in four treatments (T1: highest point in the area with superficial litterfall; T2: highest point in the area without superficial litterfall; T3: lowest point in the area with superficial litterfall; T4: lowest point in the area without superficial litterfall), to evaluate the soil seed bank, with monthly evaluation for 6 months. In the soil seed bank were counted 40 species distributed in 33 genera and 13 families. Seed density showed normality (Kolmogoro-Smirnov) and homogeneity (Bartlett), which presented a statistical difference between the treatments by the Duncan test (p <0.05). T1 had the highest amount of germinated seeds (567 individuals), but it did not differ statistically from treatments T2 and T3. T4 had the lowest amount of germinated individual (293 individuals) and the lowest richness (23 species), which also did not differ statistically from treatments T2 and T3. The diversity of Shannon differed by the Hutcheson t test (p <0.05), with emphasis on litterfall treatments. The values of richness, number of germinated individuals and diversity were influenced by the history of the area. This study evidences the importance of soil seed bank evaluation as a decisive factor for the self recovery of degraded areas or in recovery process.