Effect of climatological factors on ground-layer vegetation: a case study to assess and protect the fire-prone grasslands of Odisha, India

Vegetation diversity and the effect of fire on grassland communities in Odisha were evaluated, along with phenological behaviour in response to climatic factors. This study noted 3100 individuals from 63 grassland taxa under 12 families and 44 genera. Of these, 22 grass species and 11 non-grass species were found in burned grassland sites, while 13 grass species and 17 non-grass species were observed in unburned sites. About 81% of the examined individuals flowered in burned sites compared to 35% in unburned sites. The phytosociological investigation reveals that <i>Imperata cylindrica, Cynodon dactylon, Mimosa pudica,</i> and <i>Dichanthium annulatum</i> thrived and showed dominance after a severe fire. Phenological analyses revealed that flower initiation positively correlates with available nitrogen (<i>r</i> = 0.8, <i>p</i> &lt; 0.01) and rainfall (<i>r</i> = 0.6, <i>p</i> &lt; 0.01). However, a negative correlation was found between fruit senescence and soil moisture (<i>r</i> = -0.8, <i>p</i> &lt; 0.01). Principal component analysis revealed that rainfall and available nitrogen are the main factors explaining phenological divergence in sampling sites. This case study on the interaction between phenological data and fire may help to conserve fire-resistant species and develop a conservation strategy for grassland taxa in fire-prone regions.