Homestead landuse system and components of indigenous community enriches forest genetic resources in Eastern Himalayan landscape

The rich phyto-biodiversity of the Eastern Himalayas are at risk due to climate change, overexploitation, natural calamities, and commercialization in agriculture and forestry land use. This study aimed to ascertain the forest genetic resources (FGR), the different systems of land use, and the prevalence of bamboos in the homesteads of Tamenglong and Noney districts of Manipur, in the Indian Eastern Himalayas. The study found that 63 species of FGR (52 Native and 11 Alien) having diverse uses are being conserved in the homesteads. Native FGR of conservation concern includes Aquilaria malaccensis, Cinnamomum tamala, Garcinia pedunculata, Oroxylum indicum, Phyllanthus emblica and Toona ciliata. Seven different systems viz. AgriHortiSilviPastoral (AHSPL), AgriHortiSilvi (AHS), HortiSilvi (HS), Horti (H), Silvi (S), AgriSilviPastoral (ASPL), and HortiPastoral (HPL) land use were classified based on the composition of the crops and livestock in the total 120 homesteads studied. The study also found that bamboos (10 species) are important component found in a total of 72 land use across all the 7 classified types. Melocanna baccifera was the most common bamboo species found across five land use systems (AHSPL, AHS, HS, H and ASPL) in a total of 24 homesteads. Bambusa tulda (density 29.46 per acre), M. Baccifera (density 15.48 per acre) and Parkia timoriana (density 3.86 per acre) were the dominant FGR in AHSPL. In AHS the dominant FGRs were Gmelina arborea (density of 55.09 per acre), B. tulda (density of 21.0 per acre) and P. timoriana (density of 20.75 per acre). M. baccifera (density of 141.67 per acre), D. hamiltonii (density of 97.0 per acre) and G. Arborea (density of 91.81 per acre) were the most dominant FGR in the HS system. The Horti system had G. arborea (density of 55.09 per acre in 6 plots), M. baccifera (density of 38.52 per acre in 7 plots) as important FGR. In the Silvi system of the homesteads B. tulda has the highest density at 287.52 per acre, with D. hamiltonii (density of 230.02 per acre) and B. nutans (density of 143.76 per acre) as the second and third most prevalent FGR. In the ASPL system the dominant FGR included M. baccifera (density of 19.01), P. timoriana (density of 10.05 per acre) and C. tamala (density of 6.49 per acre). The HPL system had only two plots and hence less FGR species representation with B. Tulda (density of 14.11 per acre), Gigantochloa atter (density of 3.02 per acre) and Tamarindus indica (density of 0.50 per acre). The integration of multiple components trees, annual crops, perennial horticultural species, livestock, and in some cases aquaculture in these HLUs represents sophisticated land-use intensification that maximizes productivity while maintaining ecosystem stability and resilience to environmental variability and market fluctuations. The study thus confirmed that the homestead land use practiced by the Rongmei indigenous community are a sustainable land use system that conserves important FGR. To ensure sustenance and biodiversity enhancement bamboo-based homesteads of different component mixture can be promoted.