On the usage and measurement of landscape connectivity

TLDR

Connectivity refers to how a landscape facilitates or impedes organism movement among patches, yet the term is used inconsistently in the literature, causing confusion over function versus structure, patch isolation versus landscape connectivity, and corridors versus connectivity. The study reviews 33 recent papers on landscape connectivity, argues for restricting the term to its original definition, and proposes a new quantification method to avoid misleading conclusions. The authors analyze nine studies—both modeling and empirical—that measured connectivity per definition, explain why some conclusions are misleading, propose a revised quantification approach, and recommend a sampling‑intensity reduction method for landscape‑scale empirical studies. They found that current connectivity measurements can be misinterpreted as supporting habitat fragmentation to improve connectivity.

Abstract

This paper examines the usage and measurement of “landscape connectivity” in 33 recent studies. Connectivity is defined as the degree to which a landscape facilitates or impedes movement of organisms among resource patches. However, connectivity is actually used in a variety of ways in the literature. This has led to confusion and lack of clarity related to (1) function vs structure, (2) patch isolation vs landscape connectivity and, (3) corridors vs connectivity. We suggest the term connectivity should be reserved for its original purpose. We highlight nine studies; these include modeling studies that actually measured connectivity in accordance with the definition, and empirical studies that measured key components of connectivity. We found that measurements of connectivity provide results that can be interpreted as recommending habitat fragmentation to enhance landscape connectivity. We discuss reasons for this misleading conclusion, and suggest a new way of quantifying connectivity, which avoids this problem. We also recommend a method for reducing sampling intensity in landscape‐scale empirical studies of connectivity.