FEATURE
Figure 4 : Soil samples are taking on a bare field .
actively requiring edaphic micro and mesofauna to move downward through the soil sample , falling into a collection vessel below containing a preserving agent ( Gregorich and Carter 2007 ). Micro-arthropod extraction from soils and plant litter has been reviewed in numerous studies [ Evans et al . 1961 ; Macfadyen 1962 ; Murphy 1962 ; Edwards 1971 ; Edwards 1991 ; Coleman et al . 2017 ], and have been found to be effective and inexpensive .
One of the main limitations of utilising QBS as a measure of soil quality is the identification of Collembola to its taxonomic level , thus many indices being unable to support abundance data ( Paz-Ferreiro and Fu 2016 ). Parisi ( 2001 ) addressed these limitations by developing the Qualita Biologica del Suolo ( QBS ) index as a rapid means of characterising edaphic microarthropod populations from sampling sites without the need for taxonomic understanding of observed Collembola species .
Figure 5 : One of the vegetated sample sites .
Qualita Biologica del Suolo Collembola ( QBS-c ) is based on the concept that Collembola samples with high eco-morphological index scores ( EMI ) correlate positively with soil quality and positive edaphic functionality ( Parisi et al . 2005 ). Furthermore , results obtained with QBS-c in several studies have been validated using alternate soil quality indicators including soil organic carbon and aggregate stability ( Gardi et al . 2002 ). lembola morphotypes proportionate to their adaption level ( Parisi et al . 2005 ).
Extraction of Collembola is accomplished using Burlese-Tullgren funnels ( Figure 3 ). Extraction is achieved by applying a repellent stimulus ( incandescent light ) that dries soil from above ,
Qualita Biologica del Suolo Collembola ( QBS-c ) involves examining the extracted Collembola under a stereomicroscope at low magnifications . Extracted Collembola are then ranked according to their particular eco-morphological index ( EMI ) determination , based on phenological characteristics .
This is done by grouping them into systematic groups according to their ecomorphological forms ; Epigeic , Hemiedaphic or Euedaphic . EMI grouping is achieved by assigning a score based on phenological characteristics ; Ocelli are noted and scored a ‘ 0 ’ for present and ‘ 4 ’ for absent .
The antenna is observed and scored a ‘ 0 ’ should they be greater than its body length , a ‘ 2 ’ should they be approximately half of its body length , and scored a ‘ 4 ’ should the antenna be shorter than half the Collembola ’ s body length .
Furca is noted and scored a ‘ 0 ’ should it be fully developed , scored ‘ 2 ’ should it be reduced and scored a ‘ 4 ’ should furca be absent . Hairs and scales are noted and scored a ‘ 0 ’ should they be present and a ‘ 4 ’ should the Collembola show no discernible hairs or scales . As a gen-
13 Grassroots Vol 20 No 4 December 2020