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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).

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.

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.