Agriculture, Ecosystems and Environment 105 (2005) 323���333 Microarthropod communities as a tool to assess soil quality and biodiversity: a new approach in Italy Vittorio Parisi a, Cristina Menta a,���, Ciro Gardi b, Carlo Jacomini c, Enrico Mozzanica d a Department of Evolutionary and Functional Biology, Section Natural History Museum, University of Parma, via Farini 90, I-43100 Parma, Italy b Department of Environmental Sciences, University of Parma, Viale delle Scienze, I-43100 Parma, Italy c APAT, Department Defense of Nature, Italian Agency for Environment Protection and for Technical Services, Via Curtatone 3, I-00185 Rome, Italy d ARPA-Parma, Regional Agency for Environment Protection, Via Spalato 4, I-43100 Parma, Italy Received 3 June 2003 received in revised form 5 February 2004 accepted 11 February 2004 Abstract Traditional approaches to soil quality evaluation were based on the use of physical, chemical and microbiological indicators. Recently, new methods, based on soil microarthropods have been proposed for soil quality evaluation. Soil microarthropods have been shown to respond sensitively to land management practices and to be correlated with beneficial soil functions. In Italy, a new approach (called QBS index) based on the types of edaphic microarthropods has been proposed to assess soil biological quality. The QBS index is based on microarthropod groups present in a soil sample. Each type found in the sample receives a score from 1 to 20 (eco-morphological index, EMI), according to its adaptation to soil environment. The QBS index sums up these scores, thereby characterizing the microarthropod community of the sample being studied. QBS has been applied on a range of soil types and land uses in Italy, its validity evaluated for assessing biological quality of soil in different situations. This paper describes the QBS methods and presents three applications of the proposed methodology. �� 2004 Elsevier B.V. All rights reserved. Keywords: Soil quality Microarthropod QBS Soil fauna Mites Collembola 1. Introduction A common criterion to evaluate long-term sus- tainability of ecosystems is to assess the fluctu- ations of soil quality (Schoenholtz et al., 2000). Soil reflects ecosystem metabolism within soils, all bio-geo-chemical processes of the different ecosystem components are combined (Dylis, 1964). ��� Corresponding author. Tel.: +39-0521-236465 fax: +39-0521-533673. E-mail address: cristina.menta@unipr.it (C. Menta). Indicators of soil health or quality should ful- fill the following criteria (Doran and Zeiss, 2000): (1) sensitivity to variations of soil management (2) good correlation with the beneficial soil functions (3) helpfulness in revealing ecosystem processes (4) comprehensibility and utility for land managers (5) cheap and easy to measure. Soil quality can be evalu- ated by using a large number of indicators (chemical, physical, biological) depending on the scale and the objective of the evaluation the importance of some of these parameters is generally accepted. A review of soil quality indicators showed that there is heavy 0167-8809/$ ��� see front matter �� 2004 Elsevier B.V. All rights reserved. doi:10.1016/j.agee.2004.02.002

324 V. Parisi et al. / Agriculture, Ecosystems and Environment 105 (2005) 323���333 reliance on a few appraisals. Soil organic matter among chemical indicators (Liebig and Doran, 1999 Bowman et al., 2000 Brejda et al., 2000 Kettler et al., 2000 Gilley et al., 2001 Li et al., 2001 ), bulk density (Liebig and Doran, 1999 Kettler et al., 2000 Gilley et al., 2001 Li et al., 2001) and aggre- gate stability (Bowman et al., 2000 Six et al., 2000) among physical indicators, were the most often used but these were few examples of biological indicators of soil quality (Pankhurst, 1997 Liebig and Doran, 1999 Gilley et al., 2001). However, biological moni- toring is required to correctly assess soil degradation and correlated risks (Eijsackers, 1983 Turco et al., 1994). In particular, there is a strong need to iden- tify systems of indicators capable of expressing soil quality criteria, to be used as benchmarks in environ- mental remediation, as well as to assess and monitor soil quality in soils subjected to degradation risk (van Straalen and Krivolutsky, 1996 van Straalen, 1998 ANPA, 2002). Recently, different authors proposed new methods for soil quality assessment, based on soil microfauna. Some of these methods are based on the general eval- uation of microarthropods (Parisi, 2001), while others are based on the evaluation of a single taxon (Bernini et al., 1995 Iturrondobeitia et al., 1997 Paoletti, 1999 Paoletti and Hassal, 1999 Parisi, 2001). The application of biological indicators is often limited by the difficulties in classifying microarthropods. The introduction of a simplified eco-morphological index, that does not require the classification of organisms to species level, allows a wider application of these methodologies. The increasing recognition of problems deriv- ing from soil degradation contributed to identify soil fauna research as a priority in soil quality as- sessments (Bongers, 1990, 1999 van Straalen and Krivolutsky, 1996 Pankhurst, 1997 Pankhurst et al., 1997 van Straalen, 1997). Most edaphic animals have life cycles that are highly dependent on their immediate environment, interacting with soil in sev- eral different ways. To be able to evaluate their role and function, it is important to use methodologies that highlight either the number of species present or the processes and roles that they play in the soil environment. Mesofauna groups are a key component of soil biota. They are very abundant, their role in soil for- mation and transformation is well-recognized, the area covered during their life cycle is representa- tive of the site under examination, their life histories permit insights into soil ecological conditions and, several species have already been recognized as use- ful biological indicators of soil quality. In general, soil invertebrate-based indices consider the consis- tency and richness of populations (van Straalen, 1998 Jacomini et al., 2000). Most recently, the in- tegrated QBS index���i.e. ���Qualit�� Biologica del Suolo���, namely biological quality of soil���was pro- posed (Parisi, 2001). The objectives of this paper are to describe more fully the QBS index, and three applications of the proposed methodology. 2. Materials and methods 2.1. QBS index The QBS index is based on the following concept: the higher soil quality, the higher will be the number of microarthropod groups well adapted to soil habitats. QBS is applied to soil microarthropods, separated ac- cording to the biological form approach (sensu Sacchi and Testard, 1971), with the intention of: (1) evalu- ating the microarthropods��� level of adaptation to the soil environment life (Parisi, 1974), and (2) overcom- ing the well-known difficulties of taxonomic analy- sis to species level for edaphic mesofauna. Edaphic microarthropods show morphological characters that reveal adaptation to soil environments, such as: re- duction or loss of pigmentation and visual apparatus streamlined body form, with reduced and more com- pact appendages (hairs, antennae, legs) reduction or loss of flying, jumping or running adaptations reduced water-retention capacity���e.g. thinner cuticle, lack of hydrophobic compounds on the outer surface (Parisi, 1974). Focusing on the presence of these characters, and not requiring the complex taxonomic identification to the species level, means that non-specialists can use QBS analysis also. The main phases for obtaining QBS values are: (1) sampling (2) microarthropods��� extraction (3) pre- serving the collected specimens (4) determination of biological forms (5) calculation of QBS index (Parisi, 2001).