Fig. 2.

Structure of attributes defining soil quality. The basic attributes were measured in the field and are in bold, while the aggregate attributes form the stages leading to soil quality. Attributes within a bold box aggregate to form a higher level attribute. Thus: Earthworms and Enchytraeids combine to give Faunal pores; Faunal pores, Water retention and Air permeability combine to give Pore structure; etc. It should be noted that Decomposition occurs twice as it contributes to both Function and Losses. The abbreviated attributes are: PNR – potential nitrification rate; PDR – potential denitrification rate; ELFA – ester linked fatty acids; TEN – total extractable nitrogen; DOC – dissolved organic carbon. Nematodes contribute to both the decomposition and biodiversity attributes of soil quality (from Griffiths et al., 2010).