![]() 2000 Olson 1991 Nadkarni and Longino 1990) and for the extraction of forest-litter inhabiting Coleoptera ( Didham et al. 2002 Parr and Chown 2001 Bestelmeyer et al. 2007 Underwood and Fisher 2006 Longino et al. Winkler extraction is suitable for the extraction of litter-inhabiting, rapidly mobile Formicidae ( Delabie et al. 1978) moreover, in the Berlese extraction method, separation of soil particles and debris that drop into the collection solution along with fauna makes sampling more time-consuming and labour intensive than pitfall trapping ( Robertson 2007 Edwards 1991). ![]() Berlese extraction necessitates the use of expensive and unwieldy apparatuses and electricity, which may not be available in remote study sites ( Krell et al. Pitfall trapping is most effective in open habitats, such as grasslands and scrub vegetation because the capture values can be affected by vegetation complexity ( Melbourne 1999 Majer 1997 Greenslade 1964). 1995 Spence and Niemela 1994 Topping and Sunderland 1992 Adis 1979 Geenslade 1964). ![]() Pitfall trapping, the simplest and cheapest method among the three, is efficient in capturing those arthropod taxa that are nocturnally active on the surface, but is inefficient in capturing either the bottom dwellers or those that disseminate by flying ( Hansen and New 2005 Leather and Watt 2005 Woodcock 2005 Work et al. 2004 Fisher and Robertson 2002 Longino et al. 2005 Edwards 1991 Frith and Frith 1990), and Winkler extraction ( Anto and Thomas 2007 Philpott et al. 2007 Anu and Thomas 2006 King and Porter 2005 Richardson et al. 1995 Olson 1991 Adis 1979), Berlese extraction ( Anu et al. 1999 Holland and Smith 1999 Mommertz et al.1996 Mesibov et al. Three methods employed widely to survey ground- dwelling arthropods are pitfall trapping ( Holland and Reynolds 2005 King and Porter 2005 Ward et al. Specific methods that are effective in extracting a high proportion of these taxa are usually necessary. Since most ground-dwelling arthropods are minute and numerous, and usually not easy to detect by an unaided eye, assessment of populations of these organisms is hard and labor-intensive. Inclusion of ground-dwelling arthropods in biodiversity inventories and environmental assessment surveys has increased in the recent past ( Oliver and Beattie 1996). Significantly a greater frequency and higher abundance of arthropods belonging to Orthoptera, Blattaria, and Diptera occurred in pitfall-trapped samples and Psocoptera and Acariformes in Berlese-extracted samples than that were obtained in the other two methods, indicating that both methods are useful, one complementing the other, eliminating a chance for possible under-representation of taxa in quantitative studies. A comparison of the Berlese and Winkler extraction data shows that in a quantitative multigroup approach, Winkler extraction was inferior to Berlese extraction because the total number of arthropods caught was the lowest and many of the taxa that were caught from an identical sample via Berlese extraction method were not caught. Berlese extraction is the better method for quantitative measurements than the other two methods, whereas pitfall trapping would be appropriate for qualitative measurements. However, with possible bias towards surface-active taxa, pitfall-trapping data is inappropriate for quantitative studies, and Berlese extraction is the better alternative. Highest abundance and frequency of most of the represented taxa indicated pitfall trapping as the ideal method for sampling of ground-dwelling arthropods. The abundance of ground-dwelling arthropods was compared among large numbers of samples obtained using pitfall trapping, Berlese and Winkler extraction methods. The present study provides data to decide on the most appropriate method for sampling of ground-dwelling arthropods measured in a moist-deciduous forest in the Western Ghats in South India.
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