Chapter 9 GROUND-DWELLING INSECTS Ground-dwelling insects A profile of a typical soil shows an upper layer of recently derived vegetational material, termed litter, overlying more decayed material that intergrades with humus-enriched organic soils. These organic materials lie above mineralized soil layers, which vary with local geology and climate, such as rainfall and temperature. | TIC09 5 20 04 4 44 PM Page 217 Chapter 9 GROUND-DWELLING INSECTS A mole cricket. After Eisenbeis Wichard 1987. TIC09 5 20 04 4 44 PM Page 218 218 Ground-dwelling insects A profile of a typical soil shows an upper layer of recently derived vegetational material termed litter overlying more decayed material that intergrades with humus-enriched organic soils. These organic materials lie above mineralized soil layers which vary with local geology and climate such as rainfall and temperature. Particle size and soil moisture are important influences on the microdistributions of subterranean organisms. The decompositional habitat comprising decaying wood leaf litter carrion and dung is an integral part of the soil system. The processes of decay of vegetation and animal matter and return of nutrients to the soil involve many organisms notably fungi. Fungal hyphae and fruiting bodies provide a medium exploited by many insects and all faunas associated with decompo-sitional substrates include insects and other hexapods. In this chapter we consider the ecology and taxonomic range of soil and decompositional faunas in relation to the differing macrohabitats of soil and decaying vegetation and humus dead and decaying wood dung and carrion. We survey the importance of insect-fungal interactions and examine two intimate associations. A description of a specialized subterranean habitat caves is followed by a discussion of some uses of terrestrial hexapods in environmental monitoring. The chapter concludes with seven taxonomic boxes that deal with non-insect hexapods Collembola Protura and Diplura primitively wingless bristletails and silverfish Archaeognatha and Zygentoma three small hemimetabolous orders the Grylloblattodea Embiidina and Zoraptera earwigs Dermaptera and cockroaches Blattodea . INSECTS OF LITTER AND SOIL Litter is fallen vegetative debris comprising materials such as leaves twigs wood fruit and flowers in various states of decay. The processes that lead to the
