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Regional Scale Dryland Vegetation Classification With An Integrated Lidar-Hyperspectral Approach, Hamid Dashti, Andrew Poley, Nancy Glenn, Nayani Ilangakoon, Lucas Spaete, Dar Roberts, Et. Al. Sep 2019

Regional Scale Dryland Vegetation Classification With An Integrated Lidar-Hyperspectral Approach, Hamid Dashti, Andrew Poley, Nancy Glenn, Nayani Ilangakoon, Lucas Spaete, Dar Roberts, Et. Al.

Michigan Tech Publications

The sparse canopy cover and large contribution of bright background soil, along with the heterogeneous vegetation types in close proximity, are common challenges for mapping dryland vegetation with remote sensing. Consequently, the results of a single classification algorithm or one type of sensor to characterize dryland vegetation typically show low accuracy and lack robustness. In our study, we improved classification accuracy in a semi-arid ecosystem based on the use of vegetation optical (hyperspectral) and structural (lidar) information combined with the environmental characteristics of the landscape. To accomplish this goal, we used both spectral angle mapper (SAM) and multiple endmember spectral …


Experimental Nitrogen Addition Alters Structure And Function Of A Boreal Bog: Critical Load And Thresholds Revealed, R. Kelman Wieder, Dale H. Vitt, Melanie A. Vile, Jeremy A. Graham, Jeremy A. Hartsock, Hope Fillingim, Et Al. Aug 2019

Experimental Nitrogen Addition Alters Structure And Function Of A Boreal Bog: Critical Load And Thresholds Revealed, R. Kelman Wieder, Dale H. Vitt, Melanie A. Vile, Jeremy A. Graham, Jeremy A. Hartsock, Hope Fillingim, Et Al.

Michigan Tech Publications

Bogs and fens cover 6% and 21%, respectively, of the 140,329 km2 Oil Sands Administrative Area in northern Alberta. Development of the oil sands has led to increasing atmospheric N deposition, with values as high as 17 kg N.ha-1yr-1; regional background deposition is N.ha-1yr-1. Bogs, being ombrotrophic, may be especially susceptible to increasing N deposition. To examine responses to N deposition, over five years, we experimentally applied N (as NH4NO3) to a bog near Mariana Lake, Alberta, unaffected by oil sands activities, at …


Natural Graphite Cuboids, Andrey Korsakov, Olga V. Rezvukhina, John Jaszczak, Dmitriy I. Rezvukhin, Denis Mikhailenko Feb 2019

Natural Graphite Cuboids, Andrey Korsakov, Olga V. Rezvukhina, John Jaszczak, Dmitriy I. Rezvukhin, Denis Mikhailenko

Department of Physics Publications

Graphite cuboids are abundant in ultrahigh-pressure metamorphic rocks and are generally interpreted as products of partial or complete graphitization of pre-existing diamonds. The understanding of the graphite cuboid structure and its formation mechanisms is still very limited compared to nanotubes, cones, and other carbon morphologies. This paper is devoted to the natural occurrences of graphite cuboids in several metamorphic and magmatic rocks, including diamondiferous metamorphic assemblages. The studied cuboids are polycrystalline aggregates composed either of numerous smaller graphite cuboids with smooth surfaces or graphite flakes radiating from a common center. Silicates, oxides, and sulphides are abundant in all the samples …


Landslides Near Enguri Dam (Caucasus, Georgia) And Possible Seismotectonic Effects, Alessandro Tibaldi, Paolo Oppizzi, John S. Gierke, Thomas Oommen, Nino Tsereteli, Zurab Gogoladze Jan 2019

Landslides Near Enguri Dam (Caucasus, Georgia) And Possible Seismotectonic Effects, Alessandro Tibaldi, Paolo Oppizzi, John S. Gierke, Thomas Oommen, Nino Tsereteli, Zurab Gogoladze

Department of Geological and Mining Engineering and Sciences Publications

The Enguri dam and water reservoir, nested in the southwestern Caucasus (Republic of Georgia), are surrounded by steep mountain slopes. At a distance of 2.5 km from the dam, a mountain ridge along the reservoir is affected by active deformations with a double vergence. The western slope, directly facing the reservoir, has deformations that affect a subaerial area of 1.2 km2. The head scarp affects the Jvari–Khaishi–Mestia main road with offsets of man-made features that indicate slip rates of 2–9 cm yr−1. Static, pseudostatic and Newmark analyses, based on field and seismological data, suggest different unstable …