Rainfall Effects on the Distribution and Abundance of Conspicuous Termite Nests in Ecosystems of the Brazilian Northeast

More than 25% of termite species inhabiting tropical forests of South America build conspicuous nests. Their nests are
remarkable components of the ecosystems composition and influence the biodiversity of a wide variety of organisms from
functional groups other than termites. Thus, the evaluation of abundance and distribution of nests may represent an 
additional tool in the analysis of habitat quality in tropical forests. The density and volume of conspicuous nests 
were estimated in an east-west direction along Paraiba state, in order to assess the variation of these factors among
the studied areas. The study was carried out in eight areas of the Atlantic Forest domain (including humid highland 
forests – "Brejos de Altitude") and Caatinga. The density of nests was estimated from six plots (65 x 20 m) randomly 
established. In these plots, all nests with volume > 2,0 liters were analyzed. There was significative variation among 
areas in relation to nest density (F=2,4; P=0,03) and volume (F=2,45; P=0,03). Nests had a greater density in Caatinga
areas. The highest density value in this area was represented mainly by \textit{Constrictotermes cyphergaster}, species with strong performance in nutrient cycling in the areas of this domain. There was a negative and significant relationship
between the species composition and the rainfall of the areas (r=-0,71; P=0,04; N=8). The results indicate an influence
of environmental variables, such as rainfall, in nest density and distribution, and in the population size of termites 
throughout the studied gradient. Financial support: CNPq, CAPES