Identifying native endemic plant species in Nilgiris using the interval type 2 q-rung orthopair fuzzy Bonferroni mean operator

The Nilgiris biosphere reserve in the Western Ghats of South India is an International Biosphere Reserve. This paper focuses on the diversity of woody species found in the Nilgiri Hills’ evergreen forest. A total of 133 plant species have been identified and their quantitative features such as density, frequency, relative density, relative frequency, basal area and their absolute values were obtained. The specific purpose for plant species identification in the Nilgiri Biosphere reserve is to understand the plant vegetation characteristics, to estimate the species richness and also to identify the endemic, vulnerable and threatened species so that they can be conserved in the future. In this paper, we select the best soil type for cultivation and identify the most endemic species in the Nilgiris biosphere reserve which involves multiple criteria leading to a multi criteria decision making problem. In order to arrive to this result, we propose the notion of interval type 2 q -rung orthopair fuzzy sets in terms of trapezoidal numbers which will effectively reflect the ambiguity in these real-life circumstances. We also describe the concept of interval type 2 q -rung orthopair fuzzy sets and its implications in the scenario under discussion. Some of its properties are also discussed together with the interval type 2 q -rung orthopair Bonferroni mean operator and interval type 2 q -rung orthopair normalised weighted Bonferroni mean operator that are proposed. In order to demonstrate the efficiency of the operator and to validate it, we also compared our results with those of the existing operators.