Diversity, spatial variability, and functional roles of invertebrates in desert grassland ecosystems

TitleDiversity, spatial variability, and functional roles of invertebrates in desert grassland ecosystems
Publication TypeBook Chapter
Year of Publication1995
AuthorsWhitford WG, Forbes GS, Kerley GI
EditorMcClaran M., Van Devender T.R.
Book TitleThe Desert Grassland
PublisherUniversity of Arizona Press
CityTucson, AZ
Accession NumberJRN00188
Call Number00654
Keywordsbiodiversity, invertebrates, book, books, chapter, chapters, ecosystem dynamics, invertebrates, grassland, invertebrate community, invertebrate community, invertebrate,grassland, report, reports

Any analysis of the community structure and functional roles of desert grassland invertebrates is constrained by the fact that there are few, if any, patches of grasslands undisturbed by humans and their domestic livestock. The desert grasslands currently exist as scattered patches surrounded by large expanses of desertscrub or as a grassland matrix with shrubs. Much of the area that was desert grassland in the 1850s is now classified as desertscrub (Buffington and Herbel 1965; York and Dick-Peddie 1969). Further, the remaining desert grassland remnants are diverse in terms of soil characteristics and grass species composition. In some areas, exotic introduced grasses have become dominant; in others, remnant grasslands are dominated by species of grasses that are relatively unpalatable to domestic livestock. The invertebrate fauna of desert grasslands is incredibly diverse and includes several phyla. while mammal, bird, reptile, and vascular plant species occur in the tens to hundreds, invertebrate species in desert grasslands number in the thousands or tens of thousands, and many of the less conspicuous species have never been described by taxonomists. Much of this fauna is never seen by the casual observer. If you were asked, "What invertebrates did you see on your morning walk in the desert grassland?" your response would probably be "ants." Ants are the most conspicuous and, along with unseen subterranean termites, the most numerous macroinvertebrates in arid environments. However, the fauna of desert grasslands includes many microscopic organisms and many large but cryptic species as well as the obvious and familiar ones (Crawford 1981; Wallwork 1982). Most of what we know about desert grassland invertebrates and their general life history characteristics is based on data from economically important species (Crawford 1981).