Monitoring the vegetation coverage of the grasslands in the Poiana Ruscă Mountains using different remote sensing indices

Abstract

The development of remote sensing means and methods applied to satellite images currently allows the analysis and monitoring of the environment, a very important research direction and in full "expansion" being the analysis of the biosphere. In this context, the aim of the research presented in this article was the analysis of the vegetation cover of the meadows and the assessment of their "state", by means of remote sensing indices, applied to Sentinel 2 satellite images (fAPAR, LAI and SAVI). The analysis took into account: the percentage of radiation used by plants for photosynthesis; the amount of biomass and soil cover by vegetation. The researches were completed with the evaluation through the combined application of the three indices, on the grasslands of the Poiana Ruscă Mountains, a complex area from a physical-geographic point of view, which also determines the diversity of the vegetation of the grasslands. During a sequence of the vegetation season (March - October period), the values of all applied indices had the same trend: the lowest values in March, the "beginning" of vegetation in the mountain areas, high values in July and their gradual reduction towards the autumn period, against the backdrop of "worsening" environmental conditions. The combined evaluation of vegetation cover supported the same evolutionary trend, with 99% of grasslands in poor condition in March and 66% of them in good and very good condition in July.

Keywords

• grasslands
• vegetation
• spatio-temporal dynamics
• indices
• satellite images