Probabilistic Regularities of Soil Cover Patterns in Landscapes with Polygonal Wedge Ice
摘要
Widespread distribution of wedge ice in the permafrost zone necessitates studying the patterns of its formation development and morphological features. The paper deals with probabilistic regularities in the soil cover patterns of landscapes with polygonal wedge ice. The study was conducted at 10 key sites of the Russian Arctic, on Spitsbergen Island, and on Banks Island located in different physico-geographical environments. Using high-resolution satellite imagery, the main parameters of the polygonal networks were obtained, such as the area of polygons, the area of lakes in them, and the location of polygon centers. The results obtained allowed us to conclude that the probability of distribution of polygon areas in the regions with random wedge ice networks in different physico-geographical environments obeys the same regularity, i.e., the lognormal distribution law. Specific conditions of each site (sediment composition, climatic and geocryological conditions) affect only the distribution parameters. The lognormal distribution of polygon areas can be explained by the random process of successive subdivision of polygons by frost cracking in random, independent ratios. The distribution of the number of polygon centers within randomly selected plots showed statistically significant deviations from the Poisson distribution, which indicates that the formation of polygons cannot be considered even in the landscapes with random polygonal networks of wedge ice.