Here we investigate relationships between NDVI, Biomass, and Leaf Area Index (LAI) for six key plant species near Barrow, Alaska. We explore how key plant species differ in biomass, leaf area index (LAI) and how can vegetation spectral indices be used to estimate biomass and LAI for key plant species. A vegetation index (VI) or a spectral vegetation index (SVI) is a quantitative predictor of plant biomass or vegetative vigor, usually formed from combinations of several spectral bands, whose values are added, divided, or multiplied in order to yield a single value that indicates the amount or vigor of vegetation. For six key plant species, NDVI was strongly correlated with biomass (R2 = 0.83) and LAI (R2 = 0.70) but showed evidence of saturation above a biomass of 100 g/m2 and an LAI of 2 m2/m2. Extrapolation of a biomass-plant cover model to a multi-decadal time series of plant cover observations suggested that Carex aquatilis and Eriophorum angustifolium decreased in biomass while Arctophila fulva and Dupontia fisheri increased 1972-2008.

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Non-forest ecosystems, dominated by shrubs, grasses and herbaceous plants, provide ecosystem services including carbon sequestration and forage for grazing, and are highly sensitive to climatic changes. Yet these ecosystems are

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This is the first report of the family Tischeriidae in Colombia. We describe two new species recently discovered in the department of Valle del Cauca in southwestern Colombia: Astrotischeria ochrimaculosa Diškus, Stonis & Vargas, sp. nov., and A. colombiana Stonis & Vargas, sp. nov. The latter is a leaf miner of Asteraceae, while A. ochrimaculosa is trophically associated with Malvaceae. Astrotischeria colombiana is known only from Colombia, but A. ochrimaculosa is more widely distributed from Colombia to Peru. The new species are illustrated with photographs of their habitats, adults, male and female genitalia, and leaf mines. We comment on the rarity of tischeriids in collections and their current known distribution in the Neotropics.