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bioRxiv · 10.1101/2024.04.01.587657

Population growth poses a significant threat to forest ecosystems: a case study from the Hindukush-Himalayas of Pakistan

Abstract

Human population growth and associated increases in anthropogenic activities pose a significant threat to forest ecosystems by diminishing the natural ecosystem services these systems provide. Malam Jabba is located in District Swat Pakistans Hindukush-Himalayan temperate zone, which is renowned for ecotourism and skiing and is rich in timber-producing tree species, medicinal plants, and unique biodiversity; however, the majority of Swat Valleys population relies on Malam Jabba forests for their timber & fuelwood requirements. We examined how the deforestation rate increased with increasing human population density in Pakistans Malam Jabba area of the Hindukush-Himalayas. To identify the forest cover, remote sensing, and geographic information systems were used (RS & GIS). The study areas vegetation was analyzed with the Normalized Divergence Vegetation Index (NDVI) using multitemporal satellite images for the years 1980, 2000, and 2020. The deforestation rate from 1980 to 2020 was then determined using the decay model, and the MATLAB program was used to predict the deforestation rate for the following two decades in relation to the anticipated growth in the human population. Our result revealed that, in the last two decades, the average rate of deforestation increased from 0.7% to 1.93% per year, while the human population of District Swat increased from 1.2 to 2.3 million at a rate of 9% per year. The decay model predicts that the study areas deforestation rate will increase to 2.5% per year over the next two decades due to the forecasted 11.6% per year population growth rate. Human population growth in District Swat, Pakistan has seriously threatened the nearby forest ecosystems, and a future increase in human population will further accelerate anthropogenic activities like unsustanible tourism, fuel and timber wood collection and urbanization. Based on our results, we recommend that: (i) in addition to reforestation programs and sustainable use of forest resources, the government should implement a long-term forest management plan (ii) where the density of forest cover can be sustained at an equilibrium level dependent of population growth pressure (iii) and areas with extreme human pressure should be designated as most important for in situ conservation approach.

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Alam, N., Ullah, Z., Ahmad, B., Ali, A., Syed, K.. 2024-04-03. Population growth poses a significant threat to forest ecosystems: a case study from the Hindukush-Himalayas of Pakistan. https://doi.org/10.1101/2024.04.01.587657

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