02936nam a2200241 a 450000100080000000500110000800800410001910000300006024501740009026000470026430000100031150000410032152021560036265000110251865000160252965000120254565000220255765300110257965300110259065300360260165300130263765300440265015461972000-05-26       1999    bl uuuu     u00u1 u    #d1 aCAMARGO, A. A. de, coord.  aRelatorio anual de cooperacao tecnica entre a Companhia de Promocao Agricola - CPA e Embrapa Cerrados para estudos de avaliacao de impacto ambiental em Balsas, Maranhao.  aPlanaltina: Embrapa-CPAC, 1998-1999.c1999  a121p.  aContrato Embrapa Cod. 22300.97/044-3  aThe field studies were carried out from 1995 to 1999 in a Colonization Project of Balsas, Maranhao state. This report, presents comparative results of four years of study (1996, 1997, 1998 and 1999). This study has the objective of verifying the antropic activities in the population dynamic of the nocturnal Lepidoptera in these areas. The methodology used is the same of the previous years. The sampling of 1999 were done between February 11th and March 2th, in the areas near to plots 15 and 16 in the points MA-4 and MA-5, during an hour (20:00 h to 21:00 h). They were four nights of collecting with light traps. Moths were captured in a white sheet, hung vertically, and illuminated by a 250 Watt mercury vapor lamp. All species were captured. The first site of sampling (SI) was installed inside a agricultural farm, 600 m from the protected vegetation, the second sampling site (SII) was installed inside a preserved area, 50 meters away from the crop. The third and fourth sampling sites (SIII and SIV) were respectively located in a protected area, 400 m and 750m away from the crop. The climatic data were also logged during the collection of the samples (Temperature and Relative Humidity). Every entomological material was separated by families and species. All exemplars of each species were quantified. The ecological diversity was calculated using the Simpson index: (formula) where, n= number of individuais in the ith species and N= total number of individual in the sample; and Margalef index: D= S-1x0, 4343/logN where, S= number of species and N= total number of individuals. Besides, with the purpose of comparing the different sites in relation to composition of species, two similarity indexes were used: Morisita, where, M=(formula) and Sorensen = 2J/A+B where A= number of species in the first area, B= number of species in the second area and J=number of species shared by the two areas. It was also calculated the frequency of species related to the number of individuals too (evenness). To determine group homogeneity of Lepidoptera families and different sites of sampling. Cluster Analysis was used (STATISTICA program).  aBrazil  aLepidoptera  aCerrado  aImpacto Ambiental  aBalsas  aBrasil  aEnvironmental impact assessment  aMaranhao  aProjeto de Colonizacao Gerais de Balsas