THE GROUND CREW


Berlese Extraction

Community Diversity

Identification

So What?

References



Right beneath our feet there is a world of living organisms that most people have never seen.   In a typical forest or grassland community the soil surface is covered by one or two inches of humus, a complex mixture of organic matter in various stages of decay.   This layer of humus is teeming with a fascinating variety of living organisms that play important roles in soil fertility and nutrient cycling.   These soil dwellers represent all trophic levels:   herbivores, carnivores, omnivores, and decomposers.   Their foods include roots, seeds, fungi, dead wood, and decaying leaves.   They may be predators, parasites, or saprophytes.   This soil community is a microcosm that illustrates the complex ecological interactions among living organisms.   Its diversity is astonishing -- 15 to 20 major taxonomic groups can usually be collected in a single square-foot sample of humus, with populations of some species exceeding one million individuals per acre.

Activities:

  • Build a Berlese Funnel and use it to extract arthropods from a sample of forest soil, compost, or ground cover.

  • Use a simple identification key to learn who's who among soil-dwelling arthropods.

  • Extrapolate from random samples to calculate population density, create ecological pyramids, and compare various indices of ecological diversity.


Animal Diversity in the Soil Community

Aschelminthes -- nematodes, roundworms
Annelida -- earthworms, segmented worms
Arthropods
Chelicerates
Araneae -- spiders
Acarina -- ticks, mites
Pseudoscorpions
Opiliones -- harvestmen, daddylonglegs
Crustacea
Isopoda -- pillbugs, sowbugs, woodlice
Myriapods
Diplopoda -- millipedes, thousand leggers
Chilopoda -- centipedes, hundred leggers
Symphyla
Pauropoda
Insects
Protura
Diplura
Collembola -- springtails
Archeognatha -- bristletails
Thysanura -- silverfish
Orthoptera -- grasshoppers, crickets
Isoptera -- termites
Blattodea -- cockroaches
Dermaptera -- earwigs
Thysanoptera -- thrips
Hemiptera -- true bugs
Homoptera -- leafhoppers, planthoppers, aphids
Psocoptera -- barklice
Neuroptera -- lacewings, antlions, aphislions
Hymenoptera -- ants, wasps
Coleoptera -- beetles, weevils
Lepidoptera -- moths
Diptera -- flies
Siphonaptera -- fleas
Return to ENT 591-K HomePage John R. Meyer
Last Updated:   3 January 1998 Department of Entomology
NC State University