Wildlife fire and climate change in the forest-steppe area of Mongolia

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1 Bayarsaikhan Uudus & Batsaikhan Nyamsuren Department of Biology, School of Arts and Sciences, National University of Mongolia Wildlife fire and climate change in the forest-steppe area of Mongolia Workshop on Carbon Fluxes & Sequestration in the Ecosystems of Mongolia September 6, 2017 Ulaanbaatar

2 Effects of fire on major ecosystem processes Fire and fire ecology are among the best-studied topics in contemporary ecosystem ecology. The large body of existing literature on fire and fire ecology indicates an urgent need to synthesize the information on the pattern of fire effects on ecosystem composition, structure, and functions. Clearly, fire can shape ecosystem composition, structure and functions by selecting fire adapted species and removing other susceptible species, releasing nutrients from the biomass and improving nutrient cycling, affecting soil properties through changing soil microbial activities and water relations, and creating heterogeneous mosaics, which in turn, can further influence fire behavior and ecological processes.

3 Fire Regimes and Fire Environment Forest fire statistics for the period reveal that the majority of fires burned within the central and eastern parts of forested area. Sep. Oct. Second fire peak falls within a short period in autumn from September to October and accounts for 5 to 8 percent of all fires. The average fire season usually has two peaks. One peak is during spring from March to Mid June and accounts for 80 percent of all fires. Mar. June Source: J.G. Goldammer Global Fire Monitoring Center (GFMC), 2000 In an average year, forest fires and steppe fires occur annually. About 95 percent of steppe and forest fires in Mongolia are caused by human activities.

4 Number of fires and amount of area destroyed by fire (thousand hectares, Erdenetuya, 2010) Years Number of Fires Total burned area (thousand hectares) Average hectares burned per fire event Source: The increase in the number of fires (during ) is related to the opening of markets once highly controlled or restricted.

5 The burned area forest and steppe area, (Erdenetuya, 2010)

6 Fire case study: Tarvagatai in Khangai Mountain range Fire is a major factor which determines spatial and temporal dynamics of forest and grassland ecosystems. The Forest fire situation in Mongolia Fireweed - Chamaenerion angustifolium

7 Share of tree species by main regions. Tree species Region Central Western Eastern Larch (Larix Sibirica) Pine (Pinus Silvestris) Cedar (Pinus cembra, var. sibirica) Spruce (Picea obovate) 3 Birch (Betula sp.) Total Source: The total forest area of Mongolia is 17.5 million ha or 11.2% of the total land area. The area of potentially exploitable forest is estimated to be between 5 and 6 million ha. Data from the Global Forest Resources Assessments (FRA) 2005 indicate a total of 10.2 million ha of forest which is equivalent to 6.5 percent of total land area. Монгол орны нутаг дэвсгэрийн 8 хувийг эзэлж байна.

8 FOREST DISTRIBUTION OF TARVAGATAI MOUNTAIN Before fire, 2002 Total area of Tarvagatai Mountain protected area is 525,000 ha. Forest area is ~160,000ha.

9 Inside burnt area ~60,000 ha

10 FOREST DISTRIBUTION OF TARVAGATAI MOUNTAIN After fire, During the ground fire 2002, burnt down ~45 percent of total forested area, Tarvagatai, Khangai Mountain range.

11 FOREST DISTRIBUTION OF TARVAGATAI MOUNTAIN In

12 Moraine dam and small moraine lake in Songino river valley, Tarvagatai, Khangai Mountain range, August 2007

13 Remains of forest in valley of Songino river, Tarvagatai, Khangai Mountain range, August 2007

14 View of burnt down forested area in same locality, August, 2007 Dried out permafrost marsh area after burnt down by ground fire in July, Photo taken in August, 2007.

15 Forest regeneration

16 FOREST REGENERATION Comparisons of NDVI between Lowest NDVI values shows in August 2002, after the ground fire occurred in July, 2002.

17 FOREST REGENERATION

18 FOREST REGENERATION SEEDLING OF LARCH TREES Number of ind Forest regenerating process in a time scale нас 4 нас 3 нас 2 нас 1 нас 5 years later, after burnt down by the ground fire, documented in August 2007.

19 Forest regenerating process in a time scale 15 years later, after burnt down by the ground fire, documented in August 2017.

20 Fire in grassland or steppe area Grasslands and arid grazing cover km 2 (80 percent of the land area) Steppe fires under certain weather conditions often invade the adjacent forest-steppe and sub-taiga zones. Fire frequency was highest in tallgrass (1-3 yr), and lowest in shortgrass (maybe yr)

21 Terra and Aqua Modis data, MODIS fire product Uncontrolled fire can be serious; it rarely originates from, or near, gers or winter shelters since great care is taken in such flammable surroundings.

22 Typical steppe landscape and vegetation type in Eastern Mongolia, Fall 2016

23 View of burnt down steppe landscape, Spring 2016

24 Typical plant community in Eastern Mongolia

25 After burnt down by steppe fire

26 Effects of Fire in Grasslands: Plant growth-form Most woody species are killed Bunch-grasses more susceptible to damage by fires than sod-formers Fires raging in arid pastures are often associated with strong winds.

27 Grasses and herbs recover faster than shrubs in grasslands.

28 By visual observation, the spatial distribution of grassland fire depends on high growth of plant biomass continuously more than two years in grassland areas.

29 According to NDVI anomalies (MODIS, 250m, years) grassland fire event strongly correlated to high NDVI values of anomaly in grassland areas.

30 Conclusion Forest fire in Mongolia depends on lower precipitation and combined with summer drought (the forest fire appeared in late July, 2002). Larch seedlings growth is very slowly but growing very densely, and extending into unforested areas before the fire. Grassland fire distribution behavior depends on accumulation of burning materials in given areas of grasslands. Accumulated plant biomass of continuously more than two years in grassland areas is strongly correlated to grassland fire event in Eastern steppe of Mongolia.

31 For future works: Our research is to identify causal relationships between the local constellation of geo-ecological and anthropogenic factors on the one hand, and patterns of discontinuous permafrost, forest distribution, occurrence of forest fires and succession of vegetation after fire events (back to forest or into steppe instead) on the other hand. Both, natural forests and forests under human influence in this area, will be subjected to analysis of forest-use and fire history, soil properties, depth of the permafrost layer, hydrological parameters and vegetation. Charcoal, palaeosoils, and aeolian deposits, combined with luminescence and radiocarbon dating, will be used for reconstructing forest and landscape development prior to the onset of human influence.

32 Thank you very much for your attention!