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Spatial heterogeneity may have differential effects on the distribution of native and nonnative plant species richness. We examined the effects of spatial heterogeneity on native and nonnative plant species richness distributions in the central part of Rocky Mountain National Park, Colorado, USA. Spatial heterogeneity around vegetation plots was characterized using landscape metrics, environmental/topographic variables (slope, aspect, elevation, and distance from stream or river), and soil variables (nitrogen, clay, and sand). The landscape metrics represented five components of landscape heterogeneity and were measured at four spatial extents (within varying radii of 120, 240, 480, and 960 m) using the FRAGSTATS...
Some theories and experimental studies suggest that areas of low plant species richness may be invaded more easily than areas of high plant species richness. We gathered nested-scale vegetation data on plant species richness, foliar cover, and frequency from 200 1-m2 subplots (20 1000-m2 modified-Whittaker plots) in the Colorado Rockies (USA), and 160 1-m2 subplots (16 1000-m2 plots) in the Central Grasslands in Colorado, Wyoming, South Dakota, and Minnesota (USA) to test the generality of this paradigm. At the 1-m2 scale, the paradigm was supported in four prairie types in the Central Grasslands, where exotic species richness declined with increasing plant species richness and cover. At the 1-m2 scale, five forest...
In this study, we investigate changes in ecosystem structure that occur over a gradient of land-degradation in the southwestern USA, where shrubs are encroaching into native grassland. We evaluate a conceptual model which posits that the development of biotic and abiotic structural connectivity is due to ecogeomorphic feedbacks. Three hypotheses are evaluated: 1. Over the shrub-encroachment gradient, the difference in soil properties under each surface-cover type will change non-linearly, becoming increasingly different; 2. There will be a reduction in vegetation cover and an increase in vegetation-patch size that is concurrent with an increase in the spatial heterogeneity of soil properties over the shrub-encroachment...
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The data represent counts of Rocky Mountain Tailed Frog larvae from 8 streams in Glacier National Park, Montana. Each stream was surveyed during 5 different years. We originally sampled the eight streams during June 2001 to evaluate a time-constrained method for potential inclusion in a monitoring program. We sampled streams by turning rocks and disturbing the substrate in front of D-frame nets for 250 min, with surveyors moving progressing upstream. Surveyors focused on areas of optimal habitat (e.g., turbulent water, coarse substrates) to increase the likelihood of capturing larvae. Two surveyors sampled simultaneously for 5-min each (making one 10-min period) and called out captures to a data recorder. Surveyors...
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We investigated butterfly responses to plot-level characteristics (plant species richness, vegetation height, and range in NDVI [normalized difference vegetation index]) and spatial heterogeneity in topography and landscape patterns (composition and configuration) at multiple spatial scales. Stratified random sampling was used to collect data on butterfly species richness from seventy-six 20 � 50 m plots. The plant species richness and average vegetation height data were collected from 76 modified-Whittaker plots overlaid on 76 butterfly plots. Spatial heterogeneity around sample plots was quantified by measuring topographic variables and landscape metrics at eight spatial extents (radii of 300, 600 to 2,400 m)....
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Conclusions: Results offer support for the use of land cover as an indicator of biotic integrity estimated by both vegetation and bird communities. Strong, significant predictions of IBI scores in plant and bird communities were achieved using land cover data from every spatial extent. Plant-based IBI scores were best predicted using data from 100 m buffers and bird-based IBI scores were best predicted using data extracted from 500 m buffers. Road density and measures of the proportion of disturbed land were consistent predictors of IBI score, suggesting their universal importance to plant and bird communities. Thresholds/Learnings: Road effects on bird communities were most pronounced at the 500m spatial extent....
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Environmental Analysis Data: These data were compiled to investigate the complex interactions between environmental gradients and geographic distance across the Intermountain West of the western United States. Due to complex topography, physiographic heterogeneity, and complicated relationships with large bodies of water, spatial autocorrelation of environmental similarity may be expected. We provide an R script (VarioAnalysis.R) that uses four associated data files (annualprecip.csv, annualSWA.csv, annualtemp.csv, key.csv) to reproduce Figure 3 in Massatti et al. 2020 (see Larger Work Citation). The data files contain information on yearly soil water availability, temperature, and precipitation, which are summed...
Tags: Arizona, Botany, California, Climatology, Colorado, All tags...


    map background search result map search result map Effects of spatial heterogeneity on butterfly species richness in Rocky Mountain National Park, CO, USA The accuracy of land cover-based wetland assessments is influenced by landscape extent. Spatial and temporal relationships between the invasive snail Bithynia tentaculata and submersed aquatic vegetation in Pool 8 of the Upper Mississippi River data Robert Fire Montana Tailed Frog Data 2001-2015 Population genetic and climatic variability data across western North America, 1915-2015 Spatial and temporal relationships between the invasive snail Bithynia tentaculata and submersed aquatic vegetation in Pool 8 of the Upper Mississippi River data Effects of spatial heterogeneity on butterfly species richness in Rocky Mountain National Park, CO, USA The accuracy of land cover-based wetland assessments is influenced by landscape extent. Population genetic and climatic variability data across western North America, 1915-2015