Peat depth mapping using grid interpolation from terrestrial peat drilling points data: A case study in Zamrud National Park

¹ Department of Agrotechnology, Faculty of Agriculture, Universitas Riau, Pekanbaru, Riau, Indonesia
² Department of Marine Science, Faculty of Fisheries and Marine, Universitas Riau, Pekanbaru, Riau, Indonesia

^* Corresponding author: besrinasrul@lecturer.unri.ac.id

Abstract

Zamrud National Park is the peak of the peat dome in the Kampar Peninsula. Peat depth data is needed as a baseline to maintain the balance of the water reservoir and carbon stock. Currently, available peat depth data is predictive photogrammetric data. Soil survey activities need to be carried out to provide accurate and up-to-date data. This research aims to map the peat depth using the best grid interpolation technique. Peat depth measurements were carried out terrestrially, while peat depth mapping used inverse distance weighted, kriging, and spline interpolation techniques. Drilling observation points are arranged based on a system of longitudinal transects and transverse transects in a northeast-southwest direction. The distance between longitudinal transects is 500 m and between transects is 1,000 m. The results showed that the Zamrud National Park area has diverse peat depths ranging from 5.3 to 16.7 m. The Kriging interpolation technique gives the best mapping accuracy results. The standard deviation value is 1.9 is smaller, the accuracy value is 98.82% higher, and the thickness of the dominating peat is 8.4-9.4 m for 7,093.47 ha (24.42% of the total park area).