Ecologically-Relevant Maps of Landforms and Physiographic Diversity for Climate Adaptation Planning

<div><p>Key to understanding the implications of climate and land use change on biodiversity and natural resources is to incorporate the physiographic platform on which changes in ecological systems unfold. Here, we advance a detailed classification and high-resolution map of physiography, built by combining landforms and lithology (soil parent material) at multiple spatial scales. We used only relatively static abiotic variables (i.e., excluded climatic and biotic factors) to prevent confounding current ecological patterns and processes with enduring landscape features, and to make the physiographic classification more interpretable for climate adaptation planning. We generated novel spatial databases for 15 landform and 269 physiographic types across the conterminous United States of America. We examined their potential use by natural resource managers by placing them within a contemporary climate change adaptation framework, and found our physiographic databases could play key roles in four of seven general adaptation strategies. We also calculated correlations with common empirical measures of biodiversity to examine the degree to which the physiographic setting explains various aspects of current biodiversity patterns. Additionally, we evaluated the relationship between landform diversity and measures of climate change to explore how changes may unfold across a geophysical template. We found landform types are particularly sensitive to spatial scale, and so we recommend using high-resolution datasets when possible, as well as generating metrics using multiple neighborhood sizes to both minimize and characterize potential unknown biases. We illustrate how our work can inform current strategies for climate change adaptation. The analytical framework and classification of landforms and parent material are easily extendable to other geographies and may be used to promote climate change adaptation in other settings.</p></div

Ecoregional distribution of landforms.

<p>Ecoregional distribution of landforms.</p

Parent soil material types by landform class in the conterminous USA.

<p>Parent soil material types by landform class in the conterminous USA.</p

Landforms of the conterminous USA.

<p>(A) A landform map of the USA, with Landscape Conservation Cooperatives used by the Department of Interior to guide climate change adaptation. Labels a-h refer to inset examples and legend for class types. (B) Examples of landform classes, zoomed in to illustrate different patterns: (a) the Pacific Northwest around Mount St. Helens (1:175,000); (b) along the Missouri River at the boundary of Montana and North Dakota (1:200,000); (c) near Milton, Pennsylvania (1:500,000); (d) in the Sky Islands of southern Arizona (1:500,000); (e) Estes Park, Colorado (1:175,000); (f) near Smithfield, North Carolina (1:400,000); (g) along the Ogeechee River near Statesboro, Georgia (1:300,000); and (h) south Texas tablelands (1:200,000).</p

Level of land protection by landform class.

<p>Results from a “gap” analysis of landforms showing the level of land protection for each land form class. Level of protection follows the gap status classes [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0143619#pone.0143619.ref048" target="_blank">48</a>]: Status 1—permanent protection from conversion and natural disturbances; Status 2—permanent protection from conversion but may have some modification of natural disturbances; Status 3—protection from conversion for most areas but extractive uses may be allowed; and Status 4—no known formal legal mandates or restrictions to prevent conversion of natural habitat types.</p

Physiographic diversity in the conterminous USA.

<p>Multi-scale physiographic diversity, calculated using the Shannon-Weaver index. Labels are mean diversity by Landscape Conservation Cooperatives, with standard deviations in parentheses.</p

Landform classes in the conterminous USA at different resolutions.

<p>Landform classes in the conterminous USA at different resolutions.</p