Environmental Engineering Reference
In-Depth Information
Chapter 15
Neutral Models and the Analysis of Landscape
Structure
Robert H. Gardner
Abstract Neutral landscape models were originally developed to test the hypo-
thesis that human-induced fragmentation produces patterns distinctly different
from those associated with random processes. Other uses for neutral models were
immediately apparent, including the development and testing of metrics to charac-
terize landscape change. Although metric development proved to be significant, the
focus on metrics obscured the need for iterative hypothesis testing fundamental to
the advancement of science. In this chapter, we will present an example of an
alternative neutral model and hypothesis designed to relate the process of landscape
change to the resulting patterns observed. The methods and programme, Qrule, are
described and options for statistical testing outlined. The results show that human
fragmentation of landscapes results in a non-random association of land-cover
types. Options for additional landscape studies are discussed and access to Qrule
described in hope that these methods may be employed to advance our understand-
ing of the process that affect the structure and function of our landscapes.
15.1
Introduction
The accelerating rate and global extent of habitat loss and fragmentation are having
a direct and significant impact on species diversity (Lindborg and Eriksson 2004;
Vellend et al. 2006), the rate and extent of exotic species invasions (Hooper et al.
2005; Vitousek et al. 1997), water quality and availability (Ferrari et al. 2009;
Meyer and Turner 1992) and the productivity of ecosystems that humans depend on
for food and materials (Osher et al. 2003; Williams et al. 2004). Even local and
regional weather patterns are recognized as being significantly affected by land-
scape change (Pyke 2004; Stohlgren et al. 1998). The importance and difficulty of
understanding the immediate and long-term consequences of landscape change has
