Although defining population structure according to discrete habitat patches is convenient for metapopulation theories, taking this approach may overlook structure within populations continuously distributed across landscapes. For example, landscape features within habitat patches direct the movement of organisms and define the density distribution of individuals, which can generate spatial structure and localized dynamics within populations as well as among them. Here, we use the neighborhood concept, which describes population structure relative to the scale of individual movements, to illustrate how localized dynamics within a population of lizards (Sceloporus arenicolus) arise in response to variation in landscape pattern within a continuous habitat patch. Our results emphasize links between individual movements at small scales and the emergence of spatial structure within populations which resembles metapopulation dynamics at larger scales. We conclude that population dynamics viewed in a landscape context must consider the explicit distribution and movement of individuals within continuous habitat as well as among habitat patches.

Irreplaceable, self-organizing landforms and the endemic and ecologically specialized biodiversity they support are threatened globally by anthropogenic disturbances. Although the outcome of disrupting landforms is somewhat understood, little information exists that documents population consequences of landform disturbance on endemic biodiversity. Conservation strategies for species dependent upon landforms have been difficult to devise because they require understanding complex feedbacks that create and maintain landforms and the consequences of landform configuration on demography of species. We characterized and quantified links between landform configuration and demography of an ecological specialist, the dunes sagebrush lizard (Sceloporus arenicolus), which occurs only in blowouts (i.e., wind-blown sandy depressions) of Shinnery oak (Quercus havardii) sand-dune landforms. We used matrix models to estimate vital rates from a multisite mark-recapture study of 6 populations occupying landforms with different spatial configurations. Sensitivity and elasticity analyses demonstrated demographic rates among populations varied in sensitivity to different landform configurations. Specifically, significant relationships between blowout shape complexity and vital rate elasticities suggested direct links between S. arenicolus demography and amount of edge in Shinnery oak sand-dune landforms. These landforms are irreplaceable, based on permanent transition of disturbed areas to alternative grassland ecosystem states. Additionally, complex feedbacks between wind, sand, and Shinnery oak maintain this landform, indicating restoration through land management practices is unlikely. Our findings that S. arenicolus population dynamics depended on landform configuration suggest that failure to consider processes of landform organization and their effects on species' population dynamics may lead to incorrect inferences about threats to endemic species and ineffective habitat management for threatened or endangered species. As such, successful conservation of these systems and the biodiversity they support must be informed by research linking process-oriented studies of self-organized landforms with studies of movement, behavior, and demography of species that dwell in them.

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Abstract. The Stratospheric Aerosol and Gas Experiment III (SAGE III, 2018) instrument was launched on 19 February 2017 from the NASA Kennedy Space Center and was integrated aboard the International Space Station (ISS). SAGE III-ISS has been providing ozone profile measurements since June 2017. This paper presents an early validation of the Level 2 solar and lunar occultation ozone data products using ground-based lidar and ozonesondes from Hohenpeißenberg and Lauder as well as satellite ozone vertical products from the Atmospheric Chemistry Experiment Fourier Transform Spectrometer (ACE-FTS) instrument. Average differences in the ozone concentration between SAGE III-ISS and Hohenpeißenberg lidar observations for 1 year are less than 10 % between 16 and 42 km and less than 5 % between 20 and 40 km. Hohenpeißenberg ozonesonde comparisons are mostly within 10 % between 18 and 30 km. The Lauder lidar comparison results are less than 10 % between 17 and 37 km, and the Lauder ozonesonde comparison results are less than 10 % between 19 and 31 km. The seasonal average differences in the ozone concentration between SAGE III-ISS and ACE-FTS are mostly less than 5 % between 20 and 45 km for both the Northern Hemisphere and Southern Hemisphere. All results from these comparisons show that the SAGE III-ISS ozone solar data compare well with correlative measurements throughout the stratosphere. With few comparisons available, the percentage difference between the SAGE III-ISS lunar ozone data and the ozonesonde data is less than 10 % between 19 and 27 km. The percentage difference between the SAGE III-ISS lunar ozone data and the ACE-FTS ozone data is less than 10 % between 20 and 40 km.