Umfang:
Online Ressource (273 S., 4.565 KB)
,
Ill., graph. Darst
Inhalt:
The habitat association by forest type and distribution pattern, seasonal abundance, correlation between mean abundance and geographic range and the feeding guild and indicator properties of swallowtail butterflies (Lepidoptera: Papilionidae) were studied in a disturbed secondary protected forest reserve in Assam, Northeast India. The method of multivariate analysis by constrained canonical correspondence ordination was used for examining the effects of some independent, continuous environmental variables like altitude, rainfall, year, geographical position (latitude and longitude) on the swallowtail butterfly group and species assemblages during the two-year study period. The separating effects of season and forest type as categorical variables were examined for observing their effects on the abundance and distribution of the Papilionidae within the study area. We used the indicator (IndVal) method of Dufrene & Legendre (1997) to detect some characteristic indicator taxa within the study area by defining the indicator values of the group and species assemblages for the transects by forest types and mean seasonal abundances. The analyses were done separately for the three study sites of Garbhanga range and two study sites of Rani range based on the pooled abundance data. Line transect method was followed for sampling the butterflies within a 50 ha study area. Permanent line transects were laid within the study sites on the basis of habitat type - scattered forest and closed forest, which were selected on the basis of canopy openness and observed levels of disturbance. As the study area experiences a tropical monsoon type of climate, therefore the different diversity parameters including species richness, evenness and rarefaction estimates were examined by forest type and season. A total sample effort of 131 days across the five study sites during dry and wet seasons of the two-year study period resulted in 18,371 individuals identified from 28 species of Papilionidae ...
Anmerkung:
Göttingen, Univ., Diss., 2008
Sprache:
Englisch
Schlagwort(e):
Hochschulschrift
URN:
urn:nbn:de:gbv:7-webdoc-1709-0
