Exploration of the ecology and ex-situ conservation of Betula utilis D. Don: Insights from topography, edaphic factors, and nursery management practices

Abstract

The global mean temperature is rising at an unprecedented rate, and the investigation of ecosystem functioning and phenological events offered some of the most compelling evidence for the impact of these changes on plant species in alpine regions. The present study assessed the impact of topographic and edaphic factors on treeline structure/diversity, regeneration behavior, phenological characteristics, and ex-situ conservation of endemic and relict species, Betula utilis D. Don in the Kashmir Himalaya, India. The data was collected using a stratified random sampling method along the three altitudinal gradients of 3000–3200 m, 3200–3400 m and 3400–3600 m asl. The results revealed that IVI of this species on the Southeastern and Southwestern aspect increase from lower to higher altitude. The lower IVI value of 156.92 and 181.85 % was observed at lower altitudes, followed by 186.05 and 208.80 percent at middle altitude and higher value of 236.58 and 260.04 % at the upper altitudinal range. On the eastern slope, the maximum and minimum numbers of recruits (1375 and 593 ha^-1) were present at middle and upper altitudinal gradients, respectively. The established regeneration decreased with altitude and better regeneration was observed in the Southwest. The phenophases of B. utilis were completed earlier with an increase in altitude. Under the nursery conditions, the maximum germination of 89.11 % was recorded in the seeds subjected to 90 days of stratification while a minimum of 47.33 % was recorded under control. The satellite data observations on resource mapping showed the scattered distribution of B. utilis dominated forests at higher elevations within the Sindh Forest division in patches. B. utilis dominated forests are distributed over an area of 2746.58 ha (1.67 %) of the total 164,236.82 ha) geographical area of the division which makes its conservation highly significant. The Canonical Correspondence Analysis highlights the primary role of soil particularly sand, silt, and clay content well as bulk density in shaping the ecological distribution and regeneration patterns of B. utilis forest stands. The study's findings reveal field-based patterns related to numerous ecological characteristics of the endemic and relict species, B. utilis, which can be utilized in developing ecological restoration and conservation efforts in the region.