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As the world’s population continues to expand, the pressure on farmland, both from expansion of urban areas (United Nations, 2002) and from a need to produce more food and fiber (Hewitt and Smith, 1995; Gardner, 1996), will increase. In direct competition with the increasing demand for more food and fiber is a growing public desire for conservation of natural systems and a focus on quality of life issues (Matson et al., 1997; Jackson and Jackson, 2002; Pimentel et al., 2004).
These two societal needs are clearly linked. Unfortunately, they are antagonistic, not complementary. The impacts of intensive agriculture, needed to increase food and fiber production, extend well beyond the field border (CAST, 1999). Similarly, many species found in natural systems, both flora and fauna, do not remain within protected reserves provided for their benefit and are impacted by land-use decisions in surrounding areas. A challenge to resource managers is to develop management strategies that support both sets of needs and lead to the “right compromise” between production agriculture, sustainability, and conservation of native floral and fauna (Mineau and McLaughlin, 1996; Swift et al., 2004).
Shelterbelts and other types of linear forest systems, such as riparian buffer strips (Benton et al., 2003), can support both sets of needs and be a link between production agriculture and protection of biodiversity. These systems, both planted and naturally occurring, provide various ecosystem services (Guertin et al., 1997). While this review focuses on shelterbelts, many of the principles discussed apply to other linear forest systems. 1