Topoclimatic diversity within forest landscapes can underlie variation in water availability, which may correspond to patterns in habitat suitability of tree species with differing hydrologic niches. However, the trade‐off between the collection of data at a fine grain size over large spatial extents has limited comprehensive analyses of landscape scale variation in habitat suitability. We present a fine scale analysis of the roles of topographic gradients in moisture availability, soil water storage and fog frequency in the spatial pattern of habitat suitability for coast redwood Sequoia sempervirens, at 10 m resolution across 34 800 ha and three landscapes spanning approximately one‐third of redwood's latitudinal range. A new 10 m resolution presence‐absence map derived from airborne imaging spectroscopy was used to characterize current redwood distributions in three landscapes. Access to belowground moisture was assessed through four measures calculated from a high‐resolution LiDAR digital elevation model, soil water storage was mapped from the USDA Soil Survey Geographic Database, and fog frequency was calculated from MODIS cloud cover data. Access to belowground moisture and fog predicted variation in suitability as redwood habitat from 22–75% and predicted redwood presence and absence at 10 m resolution with 63–74% accuracy. Across all three landscapes, redwood density consistently decreased with increasing interpolated height above a stream (IHAS), but the role of other predictors varied among the sites. Our results challenge previous assumptions that redwood habitat suitability within much coarser resolutions (800 m × 800 m) can be described by a single value. The elevated habitat suitability of sites close to streams suggests that these sites should be evaluated for their potential to become microrefugia within landscapes that may become climatically‐unsuitable for redwoods at a regional scale.

中文翻译：

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加利福尼亚海岸红杉水文生态位的景观尺度变化

森林景观内的地形气候多样性可能是水可利用量变化的基础，这可能与具有不同水文生态位的树木物种的栖息地适宜性模式相对应。然而，在大空间范围内以细粒度的数据收集之间的权衡限制了对生境适宜性景观尺度变化的综合分析。我们对地形梯度在水分有效性，土壤水分存储和雾化频率在海岸红杉红杉生境适宜性空间格局中的作用进行了精细的分析，以10 m的分辨率跨越了34800公顷，分布着三幅景观，约占红木纬度范围的三分之一。从机载成像光谱学获得的新的10 m分辨率存在图被用来表征三个景观中当前的红木分布。通过高分辨率LiDAR数字高程模型计算出的四项措施评估了地下水分的可利用性，从美国农业部土壤调查地理数据库绘制了土壤蓄水量，并从MODIS云量数据计算了雾化频率。获得地下水分和雾气可以预测红木生境的适应性变化在22–75％之间，并预测10 m分辨率下红木的存在和不存在，准确度为63–74％。在所有三个景观中，红树林密度随着溪流上方插值高度的增加而持续降低（IHAS），但其他预测因子的作用因地点而异。我们的结果挑战了以前的假设，即可以用一个值来描述在更粗糙的分辨率（800 m×800 m）内对红木生境的适应性。靠近溪流的地点的栖息地适宜性提高，建议应评估这些地点在可能因气候而变得不适合区域范围红木的景观中成为微荒地的潜力。