RIBEIRO, T. O.; http://lattes.cnpq.br/9251683873331652; RIBEIRO, Terezinha de Oliveira.
Resumo:
The semi-arid northeastern region is mostly covered by the Caatinga, and this vegetation is
influenced by environmental conditions in which influences the diverse flora and fauna. The
floristic composition of the herbaceous, shrubs and trees provide food for the animals, raw
material for various purposes and keeps the seed bank as a reserve for maintenance of
vegetation. The natural regeneration processes that occur in this biome depend on the
sequence of the mechanisms responsible for depositing seeds in the soil seed bank formation
and development of these seedlings and into grown trees. These processes are related to the
presence of seed carrying tree in the areas or nearby, to the conditions of land use and climatic
factors, which can affect the properties of the soil and the organisms richness of mesofauna
and macrofauna soil that play an important role in the decomposition of the organic,
contributing to the functionality of natural ecosystems. This study aimed to evaluate the seed
bank in the soil and quantify organisms of the mesofauna and macrofauna soil in areas with
different management in semiarid region of Paraíba : 1 ) Planting of Craibeira (Tabebuia
áurea (Silva Manso) Benth. & Hook.f. ex S.Moore,), ( 2 ) degraded area without any woody
vegetation , and ( 3 ) Planting of jurema branca (Piptadenia stipulacea (Benth) Ducke), sabiá
(Mimosa caesalpiniifolia Benth) e jurema preta (Mimosa tenuiflora (Willd.) Poiret). The seed
bank study was conducted by collecting five samples of litter and soil in each area, stored at
the nursery UFCG , Campus de Patos , where they remained for about 90 days under shading
and manual irrigation for counting and identification of emerging individuals. The total
number of plants was compared between areas through the χ2 test at p < 0.05, and floristic
diversity and species richness were assessed using the Shannon - Wiener index ( H ' ) and
evenness of Uniformity ( e') . It was found in all three areas the dominance of seeds of
herbaceous species. The degraded area had the highest density of grass seed, greater number
of families and species, but lower diversity, while the planting area of craibeiras had the
highest number of seeds of tree species and herbaceous seed stock and diversity were similar
to those found in the planting area jurema and sabia. For capturing of the macrofauna we used
PROVID traps, and every 45 days we collected soil+litter samples to determine the
mesofauna, using metal rings with subsequent extraction of invertebrates present in the
sample by the type of modified Berlese Tullgren equipment. The greater abundance of
macrofauna organisms was observed in the area with planting of craibeiras while the planting
area with jurema / sabia showed higher abundance of the mesofauna organisms. The largest
groups of macrofauna abundance in different areas and periods , in order of decreasing
density, were Hymenoptera, Coleoptera and Aranea . As for the mesofauna , groups
Collembola and Acarina experienced seasonal fluctuations with the greatest diversity of
Collembola and Acarina lower diversity recorded in the period of greatest water regime in the soil.
