Introduction

The traditional studies of food webs and food chains began with pioneering efforts of Summerhayes and Elton (1923), in Spitsbergen, Norway. This early study explicitly linked detrital biotic interactions with other parts of the terrestrial and aquatic food web (Fig. 6.1). Work on detrital food webs progressed slowly for the next 20 years, although Bornebusch (1930) carried out some pioneering studies of detrital food webs and their energetics. Further insights were gained from the studies of Lindeman (1942), who developed the concept of trophic levels.

Building on the soil ecology studies funded by the U.S. Atomic Energy Commission in the late 1950s (Auerbach, 1958) and into the early 1960s, soil ecologists recognized a clear need for a more holistic study of energetics and interactions of organisms in ecosystems. This led to the ambitious effort known as the International Biological Program (IBP). The overall intent was to bring working groups together, addressing how carbon and energy flow in a wide range of terrestrial and aquatic ecosystems, with the ultimate goal being a better understanding of how ecosystems work and could be manipulated for the benefit of mankind (Blair, 1977). The main findings of the IBP were that for a wide range of grassland, desert, and forested ecosystems, the net flow into the above-ground grazing (consumer) component is only 5% or less, with the remainder entering the detrital-decomposer food web (Coleman et al., 1976). This research led to several post-IBP studies in North America and Europe to follow up on the initial results.

In the late 1970s and 1980s, a series of investigations of detrital food webs were carried out in the semiarid and arid grasslands and desert lands of Colorado and New Mexico (Coleman et al., 1977; Coleman et al.,

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