How agro-ecological services crops affect soil arthropod diversity in Mediterranean organic greenhouse production

Conventionalization of organic agriculture through input substitution, aimed to fulfill certification requirements, without improvement of natural ecological cycles in agroecosystem, is a relevant concern especially for the organic greenhouse (OGH) sector. Following a holistic approach, more resilient agroecosystems may be designed by taking advantage of Agro-ecological Services Crops (ASC) cultivation during the crops sequence and by using organic matter amendments for the soil fertility management. In this framework, we investigated ecological sustainability of three OGH production systems by studying the soil arthropods taxa. Following systems were under assessment: i) SUBST - bare soil priori to cash crop + organic fertilizer; ii) AGROCOM - ASC as green manure priori to cash crop + compost; and iii) AGROMAN ASC as dead mulch + animal manure. Monitoring of soil arthropods was performed by using pitfall traps and divided in two phases: the pre-crop period (during cultivation of ASC or bare soil in SUBST) and cash crop (kohlrabi) production. Collembola was the most abundant group during cultivation of ASC, in all tested systems and their activity density (AD) was higher in SUBST compared to other two systems. Isopoda, Araneae and Staphylinidae were significantly more abundant in AGROMAN, where manure was applied before ASC sowing. During kohlrabi cultivation Collembola group was confirmed as the most represented in all systems, with the highest values in AGROMAN. Moreover, significant differences were found among the systems for Opiliones, Myriapoda and Staphylinidae groups; with the highest abundance of all these taxa in the AGROCOM system. Results obtained indicate that an agro-ecological practices (ASC cultivation, compost and manure application) could contribute to ecological sustainability and the development of organic agriculture under protected environment.