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Abstract: Recently, rare-earth activated phosphors have gained new and exciting applications in various fields, like display and illumination, phototherapy, plant growth, etc. The phosphorconverted white light emitting diode is prime in the art of solid-state lighting owing to its numerous merits, including desired spectral distribution, excellent chemical and thermal stability, high operational lifetime, reliability, and color quality of w-LEDs for lighting. The enhancement of the color gamut of backlight w-LEDs still needs to be addressed, which requires the design of high-efficient downshifting converter phosphors featuring thermally stable luminescence. The class of materials under suitable activation exhibit applications in a particular field. The emission in the UV region (312-315nm) is widely used for phototherapy lamps. Phototherapy has proven to be an excellent therapeutic option for the treatment of various types of skin diseases. Moreover, the emission corresponds to 600-750nm for plant cultivation. The present review article describes various rare-earth activated phosphors and their impact on human and plant physiology.

The Soil Organic Carbon (SOC) stock of soil plays an important role in mitigating the effect of climate change. The soils capacity to the atmospheric carbon depends upon climate, land use and altitude of area. The present study was conducted to estimate the SOC stocks (0–25 cm soil) along the altitudinal gradient viz., low mountain ( 2500m) in associated forest, agricultural, plantations and grass land/open scrub land uses in Uttarakhand state using geospatial technique. Altitudinal zone had observed to have strong influence on the distribution of SOC stock in the state. Study confirms that upper mountain areas hold SOC stocks ranging from 51to 160 t C ha−1. This can be attributed to the fact that whole of the studied area in upper mountains falls under forests and grasslands/open scrub. In general, forest and grassland/open scrub had recorded SOC stock >51 t C ha−1 (72.7% of forest area and 77.7% area under grassland/open scrub) as compared to agriculture (18.6% of agriculture land).