Influences of Complex Topography on Microclimate Variations
in a Mountainous Forest Region of Gangwon Province

Mariam Hussain1*, Keunchang Jang2, Tae Kyung Yoon1

(1Department of Forest Science, Sangji University,
2Landslide Division, Natioanl Institute of Forest Science)

Abstract: Forests in complex terrains experience a range of microclimates due to variations in elevation, aspect (orientation), steep slopes, and topography. This diversity creates opportunities for different species to thrive under specific conditions, promoting adaptation and resilience to environmental changes. The variations in environmental conditions allow moisture transport, share nutrients, and exchange heat. To understand these mechanisms, variations of weather variables (e.g. temperature and wind) in relation to topography are explored. This paper presents high temporal observations from mountainous regions of Gangwon Province, South Korea. Mean annual and seasonal diurnal variations show a typical pattern for temperature but chaotic for winds. This study found steep slopes resulting in high turbulent regions examined by turbulence intensity (TI), kinetic energy (TKE), and wind shear. For instance, an average wind shear was 0.15 m/s with thermal gradients of −0.0011°C. The effects of topography were the prime factor for diurnal and seasonal variations for temperature and wind by analyzing mountain-ocean interactions, human-agricultural uses, and forest density against altitudes. The mountainous elevation showed a strong linear relationship between atmospheric pressure (−1.0), temperature (−0.93), RH (0.88), and wind speed (0.52). The highest mountain peak (1573 m) also determined the maximum wind speed (5.8 m/s) and RH (76 %) with minimum pressure (842.24 hPa) and temperature (3.23 °C) whereas minimum or other tendency had diverse values. The investigations of environmental conditions such as temperature and moisture variations suggest a cooler temperature caused by dense tree cover that retains moisture better than open areas. The microclimatic conditions of wind create a buffer or channel by trees and terrain that influence seed dispersal, pollination, and microhabitat suitability for different organisms. Eventually, the variations in microclimate would allow understanding of ecological exchanges in the complex topographic forests.

Keyword: Forest meteorological variables, Diurnal and seasonal patterns, Mountain observatory networks, Korean Peninsula

Acknowledgment: This research was supported by a research fund of the National Research Foundation of Korea (NRF) grant funded by the Ministry of Science and ICT of the Korea (RS-2023-00213308).