Use and misuse of landscape indices

Abstract

Landscape ecology has generated much excitement in the past two decades. One reason was that it brought spatial analysis and modeling to the forefront of ecological research. However, high expectations for landscape analysis to improve our understanding and prediction of ecological processes have largely been unfulfilled. We identified three kinds of critical issues: conceptual flaws in landscape pattern analysis, inherent limitations of landscape indices, and improper use of pattern indices. For example, many landscape analyses treat quantitative description of spatial pattern as an end itself and fail to explore relationships between pattern and process. Landscape indices and map data are sometimes used without testing their ecological relevance, which may not only confound interpretation of results, but also lead to meaningless results. In addition, correlation analysis with indices is impeded by the lack of data because of difficulties in large-scale experimentation and by complicated behavior of indices because of their varying responses to changes in scale and spatial pattern. These problems represent significant challenges to landscape pattern analysis, especially in terms of relating pattern to process. In this perspective paper, we examine the underlying problems of these challenges and offer some solutions.

Characterising urban concentration and land-use diversity in simulations of future land use

“…study area) are crucial in the application and interpretation of indicators in land-use simulation. This has been discussed by many scholars (amongst others: Turner et al 1989;Verburg and Chen 2000;Li and Wu 2004) and also proved true in our case. The impact of spatial scale is demonstrated by the urban area size dependency of our application of shape-complexity indicator, as was discussed before.…”

“…It is, however, the combined use of composition and configuration indicators at various scale levels that makes it possible to unambiguously interpret the projected spatial developments. In fact, focussing on a single indicator can often be misleading, as was also discussed by Li and Wu (2004). A high average degree of compactness, for example, is not necessarily preferable from a spatial-policy perspective, if this compactness is associated with a large number of small, compact urban areas as this may pose a serious risk to open space fragmentation.…”

Seascape ecology in Posidonia oceanica seagrass meadows: Linking structure and ecological processes for management

“…Specifically, information on the relationship between some specific metrics and ecological processes (Fig. 8) are sometimes doubtful (Li and Wu, 2004). Consequently, landscape indices should not be used alone when studying P. oceanica seascapes, while the outcomes should not be considered as the ultimate tool for management decisions but rather require coupling with other landscape procedures and interpreted using knowledge of ecological processes (Fig.…”

Modelling the Constraints of Spatial Environment in Fauna Movement Simulations: Comparison of a Boundaries Accurate Function and a Cost Function

“…The problematic includes being able to define what is the quality of the data and how it propagates in the results (Devillers et al, 2007). It also includes at what scale data should be considered (Wilkin et al, 2007) and how they should be analyzed and the results interpreted (Li & Wu, 2004). Factors such as the trophic specialization rank of species can be taken into account while defining what spatial features should be studied.…”