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Studies on past changes in vegetation are a central key to understanding modern plant distribution, to reconstructing past climates, and to testing biome and climate models. This chapter is an initial attempt to reconstruct and to map spatial changes in the vegetation across Mongolia since ca 15,000 14C yr B.P. Our work is a logical continuation of extensive studies on the late Quaternary vegetation and environments of Mongolia done by Soviet and Mongolian scientists during recent decades (Giterman et al., 1968; Lavrenko & Rachkovskaya, 1976; Dinesman et al., 1989; Logatchov, 1989; Sevastyanov et al., 1994; etc.). Since the main publications only are published in Russian and poorly accessible for the English speaking scientific community, we first briefly will summarize previous studies, which reconstructed regional vegetation changes in Mongolia. These vegetation reconstructions are broadly correct, but some major discrepancies do appear. This summary demonstrates that Mongolian pollen records, rather than other sources of paleobotanical data, are the main information source for vegetation reconstructions and that these are based on relationships between modern pollen spectra and actual vegetation. Moreover, we will describe some potential problems that different types of sediments can cause in the interpretation of fossil pollen spectra.

An analysis of modern changes in plant communities reveals that the most important active factors today are climate and human-associated modifications. Indeed major detrimental effects are exerted by both climate cycles and human activities.

The dynamics of plant cover has long received much attention and is addressed in numerous publications. Methods for the investigation of vegetation dynamics were treated in detail in the monograph Field Geobotany (Aleksandrova, 1964). Today, in addition to these conventional methods, remote-sensing (Vostokova et al., 1988a, b) GIS and ecological databases are used extensively (Trofimova & Novikova, 1994).

Mongolia is at the center of the Asian continent and for a long time it has attracted attention from European scientists. Russian scientists and explorers also were keenly interested in this part of Central Asia. Their investigations were both pragmatic and scientific in character and were aimed at understanding this country which occupied the «crown» of Asia. Studies on the vegetation cover of Mongolia carried out by Russian scientists and explorers can be roughly subdivided into three periods: Brief route observations done alongside the main tasks of an expedition; Mainly floristic investigations aimed at collecting a comprehensive inventory of the region’s flora; Geobotanical investigations accompanied by studies on the distribution of plant communities and their mapping, as well as by studies on the physiological features of plants and their ecology.

Introduction to Studies on the Vegetation of Mongolia. Natural and Anthropogenic Factors and the Dynamics of Vegetation Distribution in Mongolia. 1.1. Introduction. 1.2. Natural Features of Mongolia. 1.3. Landscape-Ecological Regions. 1.4. Landscape and Ecological Factors of Vegetation Dynamics. 1.5. Conclusion. Late Quaternary Vegetation History of Mongolia. 2.1. Introduction. 2.2. An Overview of Previous Studies. 2.3. Data Used in this Study. 2.4. Regional Pollen Records from Individual Sites. 2.5. Holocene Changes in the Distribution of Tree and Shrub Taxa in Mongolia. 2.6. Spatial Reconstruction and Mapping of Mongolian Vegetation during the Last 15,000 Years. 2.7. General Discussion and Conclusions. Assessing Present-Day Plant Cover Dynamics. 3.1. Introduction. Modern Methods for Studying and Monitoring Plant Cover. 3.2. Mountain Plant Community Dynamics. 3.3. Plant Community Dynamics in Plains and Rocky Areas. 3.4. Dynamics of Water-Associated Vegetation. 3.5. Conclusions. Analysis of Present-Day Vegetation Dynamics. 4.1. Basic Changes in Vegetation. 4.2. Regressive Plant Community Successions. 4.3. Progressive Plant Community Regeneration. 4.4. Mapping Vegetation Dynamics. 4.5. Conclusions. Strategies for Nature Management and Vegetation Conservation. 5.1. Introduction. Methods for Vegetation Conservation. 5.2. Restoration and Conservation of Botanical Successions. 5.3. Systems for the Conservation of Botanical Diversity. 5.4. Conclusions. Summary Conclusions and Recommendations. References. Appendix 1. Appendix 2. Index.

The livestock-grazing based society of Mongolia is directly dependent upon the primary production of its vegetation. Vegetation on the vast fenceless steppes of Mongolia has sustained this society for many centuries. Evenso the vegetation of Mongolia is in a very strained ecological condition, hence work on plant cover dynamics is of central importance to help sustain and develop sound considered nature management programs.

Our analysis of modern plant cover dynamics has shown bi-directional successions in various plant communities with some ecosystems recovering and some being degraded currently in Mongolia. Across Mongolia the largest areas are occupied by plant communities that have been exposed to human-associated effects to varying extents and which are at different degradation stages. This vegetation degradation is a result of immediate and long-term human-associated modifications, the widespread effects of natural climatic cycles, water erosion processes, and strong wind movement of soils. Human effects of great importance now are: an expanded and intensive economic exploitation of natural resources; population growth caused by new enterprises to develop mineral resources; the growth of cities; and the widespread construction of new built-up areas. These are illustrated in the maps Ecosystems of Mongolia (1995) partially shown in Figure 5.1, which demonstrate some ecosystem disturbances with respect to vegetation degradation. Figure 5.1 shows some affects on plant cover with reference to grazing livestock breeding, to tree fellings, and to fires in forest steppes.