Landsat based distribution mapping of high-altitude peatlands in Hindu Kush Himalayas – a case study of Broghil Valley, Pakistan

In the alpine regions of Hindu Kush, Himalayas and Karakorum, climatic and topographic conditions can support the formation of peat, important for the livelihood of the local communities, and ecological services alike. These peatlands are a source of fuel for the local community, habitat for nesting birds, and water regulation at source for rivers. Ground-based surveys of high-altitude peatlands are not only difficult, but also expensive and time consuming. Therefore, a method using cost-effective remote sensing technology is required. In this article we assessed the distribution and extent of high-altitude peatlands in a 2000 ha area of Broghil Valley using Landsat 8 data. The composite image was trained using a priori knowledge of the area, and classified into peatland and non-peatland land covers using a supervised decision tree algorithm. The Landsat-based classification map was compared with field data collected with a differential GPS. This comparison suggests 82% overall accuracy, which is fairly high for high altitude areas. The method was successfully applied and has the potential to be replicated for other areas in Pakistan and the high-altitude regions of the neighbouring Asian countries.