Agriculture Reference
In-Depth Information
chapter 1
Soil ecology and agroecosystem studies
A dynamic and diverse world
David C. Coleman
University of Georgia
Vadakattu V.S.R. Gupta
CSIRO Ecosystem Sciences Division
John C. Moore
Colorado State University
Contents
1.2.1 The origins of organic material ............................................................................... 4
1.2.2 The importance of litter quality and nutrients...................................................... 6
1.2.3 The importance of aggregate formation in soils ................................................... 7
1.2.4 The roles of soil microbes and invertebrates ......................................................... 7
1.4.1 Biodiversity in agricultural and agroforestry systems ...................................... 11
1.4.2 Changes in land use and impacts on detrital food webs................................... 15
1.1 Introduction
Soil organic matter (SOM) is a complex of many organic molecules of varied forms, repre-
senting one of the more important components of detritus in terrestrial ecosystems. The
maintenance and rehabilitation of SOM are considered to be desirable goals in agroeco-
systems (Coleman et al., 1984, 1994; Bossuyt et al., 2002). SOM maintains soil structural
stability and enhances water-holding capacity, soil fertility, and crop production, ensuring
long-term agricultural ecosystem stability (Hassink et al., 1997; Denef et al., 2004). For these
reasons, the impacts of agricultural practices on detritus in general through SOM are the
focus of this chapter.
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