02178nas a2200205   4500008004100000245010100041210006900142490000700211520149900218653002701717653001801744653002501762653001901787653002201806100001501828700001701843700002301860700001901883856007001902       2019                        eng d00aHyperspectral analysis of leaf pigments and nutritional elements in tallgrass prairie vegetation0 aHyperspectral analysis of leaf pigments and nutritional elements0 v103 a<p>Understanding the spatial distribution of forage quality is important to address critical research questions in grassland science. Due to its efficiency and accuracy, there has been a widespread interest in mapping the canopy vegetation characteristics using remote sensing methods. In this study, foliar chlorophylls, carotenoids, and nutritional elements across multiple tallgrass prairie functional groups were quantified at the leaf level using hyperspectral analysis in the region of 470&ndash;800 nm, which was expected to be a precursor to further remote sensing of canopy vegetation quality. A method of spectral standardization was developed using a form of the normalized difference, which proved feasible to reduce the interference from background effects in the leaf reflectance measurements. Chlorophylls and carotenoids were retrieved through inverting the physical model PROSPECT 5. The foliar nutritional elements were modeled empirically. Partial least squares regression was used to build the linkages between the high-dimensional spectral predictor variables and the foliar biochemical contents. Results showed that the retrieval of leaf biochemistry through hyperspectral analysis can be accurate and robust across different tallgrass prairie functional groups. In addition, correlations were found between the leaf pigments and nutritional elements. Results provided insight into the use of pigment-related vegetation indices as the proxy of plant nutrition quality.</p>10aHyperspectral analysis10aLeaf pigments10aNutritional elements10aremote sensing10atallgrass prairie1 aLing, B.H.1 aGoodin, D.G.1 aRaynor, Edward, J.1 aJoern, Anthony  uhttps://www.frontiersin.org/articles/10.3389/fpls.2019.00142/full02414nas a2200157   4500008004100000245010000041210006900141300001400210490000600224520187700230100002302107700002502130700001902155700001902174856006302193       2017                        eng d00aComplex variation in habitat selection strategies among individuals driven by extrinsic factors0 aComplex variation in habitat selection strategies among individu  a1802-18220 v73 a<p>Understanding behavioral strategies employed by animals to maximize fitness in the face of environmental heterogeneity, variability, and uncertainty is a central aim of animal ecology. Flexibility in behavior may be key to how animals respond to climate and environmental change. Using a mechanistic modeling framework for simultaneously quantifying the effects of habitat preference and intrinsic movement on space use at the landscape scale, we investigate how movement and habitat selection vary among individuals and years in response to forage quality&ndash;quantity tradeoffs, environmental conditions, and variable annual climate. We evaluated the association of dynamic, biotic forage resources and static, abiotic landscape features with large grazer movement decisions in an experimental landscape, where forage resources vary in response to prescribed burning, grazing by a native herbivore, the plains bison (Bison bison bison), and a continental climate. Our goal was to determine how biotic and abiotic factors mediate bison movement decisions in a nutritionally heterogeneous grassland. We integrated spatially explicit relocations of GPS-collared bison and extensive vegetation surveys to relate movement paths to grassland attributes over a time period spanning a regionwide drought and average weather conditions. Movement decisions were affected by foliar crude content and low stature forage biomass across years with substantial interannual variation in the magnitude of selection for forage quality and quantity. These differences were associated with interannual differences in climate and growing conditions from the previous year. Our results provide experimental evidence for understanding how the forage quality&ndash;quantity tradeoff and fine-scale topography drives fine-scale movement decisions under varying environmental conditions.</p>1 aRaynor, Edward, J.1 aBeyer, Hawthorne, L.1 aBriggs, J., M.1 aJoern, Anthony  uhttps://onlinelibrary.wiley.com/doi/full/10.1002/ece3.2764