Soil arthropod diversity in organic, integrated and conventional olive orchards in Crete

Summary

Soil fauna biodiversity and its functional counterpart were monitored in 24 olive orchards under conventional, organic and integrated management located in eight different locations for a year in Messara valley, in southern Crete. In each location three neighbouring orchards under different management were monitored. Pitfall traps were used as trapping method and fixed data collection points were used in each olive orchard for arthropod fauna monitoring. Counter groups of functional taxa were defined, with respect to services of biological pest control and of nutrient cycling in the olive agroecosystem, Monitoring took place weekly for 5 weeks per season, all year around. Comparison of the different management systems in terms of abundance and diversity of soil arthropods and functional groups was performed. Formicidae, Coleopteran family of Tenebrionidae, Araneae, Colembola and Opiliones were the most abundant taxa found in the olive orchards. A trend of higher total abundance and richness was found in the organic olive orchards, however not statistically significant. Functional arthropod abundance followed a similar trend. Diversity indices did not show a constant pattern in terms of management system comparison; however a trend of higher diversity appeared in the less-intensified organic orchards.