The Impact of N Input on Plant Functional Traits Such as C3, C4, Native, and Non-native in Terms of Abundance, Frequency, and Density

Abstract

This study investigates the ecological changes in grassland vegetation at Banaras Hindu University’s horticulture field. Caudatemethods were used for vegetation analyses. In 72 experimental plots of 1×1m2, repeated quadrat sampling yielded 176 herbs. Plantfunctional types such as legumes, non-legumes, grasses, forbs, and sedges were classified as C3, C4, native, and non-natives traitsbased on their frequency, abundance, and density. From the rainy season of 2016 to the summer season of 2019, the mean values offrequency, abundance, and density against the N gradient were calculated. Therefore the results showed that, nitrogen is essential forthe competitive equilibrium of C3 and C4 species. This study suggests that N deposition-induced changes in competitive interactionsmay be disadvantages to native species that thrive in low-nutrient environments, such as N2-fixers, ultimately leading to changes in thecomposition of plant communities. In comparison to N2 fixers, non-N2 fixers appear to be more effective at using extra N for growth.Our findings show that the diversity of grasslands has dramatically shifted from native to introduced species, proving that non-nativespace invaders are destroying the rich grassland ecosystems around the world. By changing the dominant species and its response towhich species dominates the response at the community level, this change in abundance may alter the ecosystem functions. Based onour study, the vegetation was found to be heterogeneous up to N dosage of 60 kg/ha/year.