Principles of Classification and Mapping of Permafrost in Central Asia
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Permafrost, Phillips, Springman & Arenson (eds) © 2003 Swets & Zeitlinger, Lisse, ISBN 90 5809 582 7 Principles of classification and mapping of permafrost in Central Asia G.F. Gravis & E.S. Melnikov Institute of Earth Cryosphere, Russian Academy of Sciences, Moscow, Russia Guo Dongxin, Li Shuxun, Li Shude, Tong Boliang, Zhao Lin & Nan Zuotong Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou, China N. Sharkhuu Institute of Geography, Mongolian Academy of Sciences, Ulaanbaatar, Mongolia A.P. Gorbunov, S.S. Marchenko & E.V. Seversky Permafrost Institute, Russian Academy of Sciences, Kazakhstan Alpine Geocryological Laboratory, Almaty, Kazakhstan ABSTRACT: The agreement to prepare a uniform permafrost map of Central Asia by an international team (China, Mongolia, Russia and Kazakhstan) was reached at the International Symposium in Mongolia in September 2001. In this paper we consider some initial results of mapping mountain and plateau permafrost in Central Asia as the first step for geocryologists of the four countries. A brief review of the experiences in small-scale mapping of permafrost in Russia, China, Mongolia and Kazakhstan is provided. We distinguish two types of cryogenetic zones: high-latitudinal (polar) and low-latitudinal (alpine). The altitude of 500 m a.s.l. is suggested as a criterion for division of permafrost area into two types of cryogenesis. We propose two morphological types of alpine cryogenesis within the Central Asian permafrost area: mountain and plateau. General regularities of permafrost distribution, its structure and temperature, ice content and distribution of periglacial phenomena in the Central Asian permafrost area are briefly described. 1 INTRODUCTION of southern Russia, Mongolia, China, Kazakhstan and adjacent countries (Figure 1). At present, except for The distribution, mapping and modeling of permafrost the IPA permafrost map (Brown et al., 1997), there is in Argentina, Canada, China, Kazakhstan, Mongolia, no uniform map of Central Asian permafrost conditions. the Nordic and European countries, and Russia were one However, small scale permafrost maps have been of the major topics of the International Symposium on compiled for Central Asian territories of these regions. Mountain and Arid Land Permafrost which took place in Heginbottom et al. (1993) summarised corresponding Ulaanbaatar, Mongolia, September 2–4, 2001. Accord- major developments in permafrost mapping. The fol- ing to the first recommendation of the Symposium, an lowing is a brief review of these mapping approaches. international team of experts (China, Kazakhstan, Mongolia and Russia) is required to prepare a uniform 2.1 China map of Central Asian permafrost (Brown, 2001). Mapping of mountain permafrost of Central Asia is The map of snow, ice and frozen ground in China complicated by two circumstances. First, nonuniform (1:4,000,000), compiled by Lanzhou Institute of approaches, and as a whole, lack of studies of perma- Glaciology and Geocryology, Academia Sinica (1988) frost in this vast region. Secondly, lack of distinctions in shows regional distribution of the three types of frozen the principles of permafrost mapping. The poor infor- ground and the cryogenetic phenomena in these per- mation about frozen ground in the majority of moun- mafrost regions. These are (1) high latitute permafrost tains of Central Asia requires an understanding of the in Northeast China, (2) permafrost on Qinghai-Xizang general regularities of permafrost formation. It is impor- Plateau and (3) alpine permafrost in mountains of tant to analyse the experiences of permafrost mapping in the different countries and to employ a common usage of this experience. This collective experience and choice of the most acceptable methods of classifying and mapping are the basis for development of the uniform approach to the compilation a permafrost map of Central Asia. 2 SMALL-SCALE MAPPING OF MOUNTAIN PERMAFROST IN CENTRAL ASIA The Central Asian region is the largest area of alpine per- mafrost in the world. This region includes the territories Figure 1. The Central Asian permafrost region. 297 West and East China. Permafrost conditions of the ter- map (scale 1:5,000,000) was completed in 1970. In ritory along the Qinghai-Xizang Highway have been 1982 one more variant of this map (scale 1:7,500,000) studied in detail and mapped (Tong et al., 1983) at the was published (“Geocryological map of USSR”, 1982). scale of 1:600,000. The distribution map (1:4,000,000) The compilation of the Geocryological map of of frozen ground in China was compiled by Xu & Guo the USSR (scale 1:2,500,000) was started at the Geocry- (1982). The relation of climate, vegetation, soils and nat- ology Department of the Moscow State University ural landscapes determine the latitudinal zonation from under the initiative of V.I. Kudryavtsev (Kudryavtsev south to north of Northeast China (Guo et al., 1981). et al., 1977). The map was completed in 1991 under A map of permafrost and periglacial phenomena the direction of E.D. Ershov and subsequently pub- distribution on Qinghai-Xizang Plateau and adjacent lished (Ershov, 1996). The map is the most complete mountain regions was compiled at 1:3,000,000 (Li & source of the geocryologic–cartographic information Cheng, 1996). The map reflects the boundaries of for the territory of Russia (see Williams and Warren regions such as predominantly continuous permafrost, 1999 for the English language translation). sporadic permafrost, seasonally frozen ground, short- The Map of Morphology and Permafrost Tem- term frozen ground, as well as the distribution of perature of Northeast and South of Siberia (scale periglacial phenomena. 1:2,500,000), compiled under the direction of I. A. A Map of Geocryological Regionalization and Nekrasov (1976) is an example of a special geocry- Classification in China at a scale of 1:10,000,000 has ological map. The relation between temperature and appeared as an appendix in the book “Geocryology thickness of permafrost was used within the mountain in China” (Zhou et al., 2000). Permafrost regions of territories. Another example is the special Geocry- China are divided into three major frozen ground ological Map of USSR (scale 1:4,000,000) compiled regions: Eastern, Northwestern and Southwestern. under the direction of A. I. Popov (1985). Two types of Within each region of frozen ground, sub-regions are distribution of cryolithogenesis are shown: syngenetic identified. In the Nortwestern and Southwestern regions and epigenetic, and the composition of ground and typ- sub-regions are selected as consistent with geomor- ical cryogenic textures are shown. phological units. The geocryological mapping on the landscape base Generally, the principle of mapping mountain and began to develop in 1960s in Western Siberia (Melnikov, plateau permafrost in China is based on permafrost 1981). Here geocryological maps were made only for zonality index or on degree of permafrost thermal sta- the plains. The first attempt to use the experience of bility depending on mean annual ground temperatures these operations for mapping of the entire permafrost (Cheng, 1983, Cheng & Dramis, 1992). A GIS-based area of Russia there was Geocryological Map of Russia map of permafrost distribution and thickness on and Mongolia (scale 1:10,000,000) compiled under Qinghai-Xizang Plateau using simulated data of soil the direction of E.S. Melnikov in 1993, which incor- temperature measurements from Chinese weather sta- porated into the circumarctic map (Brown et al., 1997). tions was presented recently (Nan et al., 2001). The compilation of such a map was possible due to appearance of landscape maps covering all territories of 2.2 Mongolia the former USSR (Isachenko, 1985; Gudilin, 1987). The most recent usage of landscape contours for Permafrost in Mongolia is concentrated in Altai, geocryological mapping is demonstrated on the Hovsgol, Khangai and Khentei mountainous regions. 1:7,500,000 map by Melnikov et al. (1996). The Distribution, thickness and temperature of permafrost mountains areas are depicted in differing colours for in Mongolia vary with altitudinal zonation of mountains. the altitudinal belts: arctic deserts and stony tundra; Based on altitudinal zonation of changes in permafrost mountain tundra; mountain sparse growth of trees; distribution geocryological maps of Mongolia have been mountain taiga; and mountain steppes. Within the alti- compiled (Gravis et al., 1990) at a scale of 1:2,500,000. tudinal belts the boundaries of complexes of cryo- The southern Siberian permafrost is characteristic of genic geological processes were delineated depending Mongolian territory. The southern permafrost boundary on relief and composition of ground. in Mongolia has not been studied and determined suffi- ciently. Permafrost conditions in the Selenge River Basin 2.4 Kazakhstan have been studied and mapped relatively well as com- pared to other territories of Mongolia (Sharkhuu, 1993). The problems in the study of geocryological condi- tions of the mountain countries were specifically 2.3 Russia analysed by members of the Kazakhstan Alpine Geocry- ological Laboratory of Permafrost Institute SB RAS In 1956, I.Y. Baranov created the first geocryological under the direction of A.P. Gorbunov. Geocryological map of the USSR (scale 1:10,000,000). The updated conditions of Pamir, Gissaro-Alai, Tien Shan and 298 Table 1. Characteristics of comparing principle and terminology for permafrost zonation used in each country of Central Asia. Country (author), land Principle of permafrost Terminology of form and region zonation permafrost distribution Permafrost extent CHINA 1.1. Middle height mountain Latitudinal zones Islands Ͻ30% region in the North-East Predominantly continuous 30–75% China (Xu & Guo, 1982). 1.2. Quinghai-Xizang Index or degree of Down belt 0° to Ϫ0.5°C High Plateau (Cheng, 1983). permafrost thermal Middle belt Ϫ0.5° to Ϫ3°C stability Up belt ϽϪ3°C 1.3. Alpine mountains in West and Altitudinal belts Islands East China (Zhang et al., 1985). Predominantly continuous KAZAKHSTAN (Gorbunov et al., 1996) High Altitudinal subbelts Sporadic Ͻ40% Alpine Tien Shan and Pamir Discontinuous 40–80% mountains.