Ecological assessment and suitability ranges of Ban oak (Quercus oblongata D. Don) in Chamba district, Himalayas: implications for present and future conservation

Quercus oblongata D. Don is a multipurpose tree of ecological and economical importance. Continued overuse for forage and fuel purposes has resulted in the rapid decimation of its natural habitats. Therefore, the present study was undertaken to assess the population status, regeneration pattern, and habitat suitability model (in present and future) of Q. oblongata in the temperate forest ecosystem of the northwestern Himalaya. We sampled 14 populations, representing 3 major habitats and 6 aspects between 812 and 2266 m amsl and with 14°–65° slope, to determine nonparametric measures of diversity. In total, we recorded 188 species (Trees: 30; Shrubs: 33 and Herbs: 125) belonging to 162 Genera and 66 Families. Density of Quercus oblongata ranged between 90 and 580 Indha −1 . Total basal area varied from 11.18 to 80.95 m 2 ha −1 . The concentration of dominance varied between 0.31 and 0.99. H ' of trees varied from 0.07 to 0.49. The MaxEnt model calibration test yielded satisfactory results (AUC mean = 0.825 ± 0.02). The mean temperature of the wettest quarter (BIO_09) was the most influential variable and had a permutation importance of 71.40%. The model identified an area of 1865 km 2 as high suitable for the reintroduction of Q. oblongata . In the CCSM4 model, future projections for RCP 4.5 and 8.5 (2050 and 2070, respectively) are remarkably close to the present distribution. Total above ground biomass density ranged from 13.01 to 164.94 Mgha −1 . Total below ground biomass density from 3.77 to 61.53 Mgha −1 and total carbon density ranged from 8.39 to 106.39 Mgha −1 . In conclusion, our study identified factors that define environmentally suitable areas for the occurrence of Q. oblongata , representing the first distribution model for the Chamba district. These findings can be used to guide government policies to protect this species.