Effect of ethnicity on the plant species diversity in the traditional agroforestry system of upper Brahmaputra valley region of Northeast India

Abstract

Abstract The traditionally rich agroforestry systems are usually sustained on the basis of choice, need and importance of plants. Indigenous knowledge of ethnic communities is associated with the inherent tradition of natural resource conservation based on their customary religious beliefs. The present study aims to assess plant species diversity and understand the effect of various factors on the plant diversity of home garden agroforestry system among three ethnic tribes of Dhemaji district viz. Mishing, Bodo and Sonowal Kachari residing in the unique floodplain system of Brahmaputra valley region of Assam, Northeast India. A total of 368 plant species were recorded with herbs being the most abundant (159 species) followed by trees (148 species) and shrubs (63 species). The Sonowal Kachari home gardens with 294 species contributed higher species richness followed by Mishing (244 species) and Bodo tribe (214 species). Sorenson similarity index revealed high similarity in plant species composition between the Mishing and Sonowal Kachari tribe home gardens in comparison to others. Home garden size and proximity of gardens to major roadways had a significant positive effect on species richness and diversity of plant, while duration of flood and ethnicity had a negative effect on the same. Home gardens may prove to be an important and effective component in formulating robust strategies for management and conservation of plant species having high economic prospect especially in the flood prone areas. The information generated from the present study will help to develop a better understanding of the agroforestry system of the ethnic communities, their preferences of plantation and development of home garden agroforestry systems towards achieving the goals of sustainable livelihood, while contributing to biodiversity conservation.