Temperate Forest Watersheds: Responses to Atmospheric Pollutants and Climate Change

Transcription

1 Temperate Forest Watersheds: Responses to Atmospheric Pollutants and Climate Change Myron J. Mitchell Distinguished Professor SUNY College of Environmental Science and Forestry Syracuse, New York, USA

2 Effects of Acid Rain (Atmospheric Acidic Deposition) Historical Patterns of SO 2 emissions Linkages to surface water chemistry Watershed sulfur budgets Effect of acidic deposition in China Importance of nitrogen Global Climate Change Importance of climate change in East Asia Concluding Statements

3 Effects of Acid Rain (Atmospheric Acidic Deposition) Historical Patterns of SO2 emissions Linkages to surface water chemistry Watershed sulfur budgets Effect of acidic deposition in China Importance of nitrogen Global Climate Change Importance of climate change in East Asia Concluding Statements

4 Processes Involved in Acid Deposition Sources

5 The Effects go beyond on that of Acid Deposition Acidic mobile, anions (SO 4 2- and NO 3- ) result in the mobilization of cations. Nutrient cations (Ca 2+, Mg 2+, K + ) may be lost. Acidic cations (H +, Al +3 ) may be mobilized in soils and surface waters. Al +3 may be toxic to aquatic (i.e., fish) and terrestrial vegetation (i.e., fine roots)

6 Effects of Mobile Anions on Cation Leaching in Soil Nutrients Toxic to Biota

7 Other Problems Related to Acidic Deposition Degradation of materials. Interactions with other air pollutants including O 3, NO x and hydrocarbons. Fixed N inputs are causing eutrophication of coastal waters that are N limited. Interrelationships with global change including, climate alteration, biotic diversity and carbon budgets.

8 Effects of Acid Rain (Atmospheric Acidic Deposition) Historical Patterns of SO 2 emissions North America Europe Asia Linkages to surface water chemistry Watershed sulfur budgets Effect of acidic deposition in China Importance of nitrogen Global Climate Change Importance of climate change in East Asia Concluding Statements

9 SO 2 Emissions in U.S.A Peaked Mid-1970 s U.S. EPA

10 SO 2 Emissions in Europe peaked in 1980 s Figure 1. Historical development of sulfur dioxide emissions in Europe (Unit: Tg SO2) from Vestreng et al Emissions Peaked in 1980 s

11 In Asia emissions are still increasing. From Streets et al. (2000) Atmospheric Environment

12 Effects of Acid Rain (Atmospheric Acidic Deposition) Historical Patterns of SO 2 emissions Linkages to surface water chemistry Watershed sulfur budgets Central European watershed case studies North American watershed case studies Effect of acidic deposition in China Importance of nitrogen Global Climate Change Importance of climate change in East Asia Concluding Statements

13 Black Triangle Intensive study watersheds in Central Europe for examining sulfur budgets. Black Triangle: area of pollutants from lignite coal

14 *Syracuse

15 Highest inputs of S and N in northern China, but ph also high due to high [base cations] e.g. Ca 2+. From: Wang, W. and T. Wang Atmospheric Environment 30: μeq L -1 ph Acid Rain in China Acidity 2- SO 4 - NO 3 + NH 4 Ca South-1986 South-1993 North-1986 North-1993 Location and Year

16 Effects of Acid Rain (Atmospheric Acidic Deposition) Historical Patterns of SO 2 emissions Linkages to surface water chemistry Watershed sulfur budgets Effect of acidic deposition in China Importance of nitrogen Changes in relative contribution of sulfur and nitrogen Nitrogen Cascade Nitrogen concentrations in Japanese surface waters Global Climate Change Importance of climate change in East Asia Concluding Statements

17 100 Wet-Only Preciptation Huntington Forest Relative contribution of NO 3 increasing 80 SO4 NO3 Cl μeq L Mitchell et al. unpublished data (New York State) Year

18 Atmosphere Smog formation Visability NO x NH 3 Nitrogen HNO 3 Acidification NO 2 Global Warming Cascade Terrestrial Ecosystems NH 4 + NO 3 - From: Galloway et al. (2003) BioScience Freshwater Ecosystems Changes in Biotic Diversity Coastal Eutrophication

19 High NO 3 - in area of high N deposition Nitrate concentration in forest stream water during base flow (Shibata et al. 2001) 1.0 mg N L mg N L -1

20 Effects of Acid Rain (Atmospheric Acidic Deposition) Historical Patterns of SO 2 emissions Linkages to surface water chemistry Watershed sulfur budgets Effect of acidic deposition in China Importance of nitrogen Global Climate Change Linkage of climate change with changes in chemistry of alpine lakes in Europe Nitrate loss linked with snow melt in forested watershed in North America Linkage of sulfur watershed budgets and climatic events Importance of climate change in East Asia Concluding Statements

21 Change in Albedo

22

23 Time series. (a) River and stream water temperatures (RWT) measured in Switzerland from 1965 to 2002 (b) Air temperature in Switzerland, Hurrell s (1995) winter NAO index (NAOwin) and the brown trout catch in the 87 river sections. From Hari et al. (2006). Global Change Biology Linkage of water temperature and fish survival in Switzerland

24 Water Chemistry and Climate Change Linked: Conductivity, sulfate, calcium, and magnesium in two high alpine lakes in of Rasass See in Italy (black triangles) and Schwarzsee ob Solden in Austria (open circles) ( ). From Thies et al. (2007) ES&T

25 Snowpack depth (cm) concentration (μmol L -1 ) Runoff (mm day -1 ) NO /95 a c 1/96 2/96 Temperature NO 3-3/96 4/96 Snowpack Runoff 5/ Daily average air temperature ( o C) Daily average air temperature ( o C) Responses of snowpack depths, runoff amounts, and nitrate concentrations in drainage water from the Archer Creek catchment to temperature changes from December 1995 to May Adirondack Mountains, New York State) Park et al. Global Change Biol. (2003)

26 Relationships between average air temperatures and NO 3- export in Arbutus Lake outlet for either the entire year or the months preceding spring snowmelt from 1984 to Winter air temperature major driver of NO 3- export. Our current research is trying to evaluate what is causing this relationship. export from Jan - Mar (mol ha -1 period -1 ) - Annual NO 3 export (mol ha -1 yr -1 ) NO a. January - December R 2 = 0.30, P = b. January - March R 2 = 0.72, P < Average daily air temperature C

27 Sulfur and Climate Change High concentrations of S aerosols in the atmosphere result in less warming. High sulfur loading in the past has resulted in sulfur storage in soils and wetlands. Sulfur stored in wetlands is stored as sulfide. When wetlands become oxidized (lowering of water table) the stored sulfide is oxidized to sulfuric acid (similar to acid mine drainage): 6FeS O 2 + 6H 2 O ---> 6FeSO 4 + 6H 2 SO 4 Changes in hydrology predicted with global climate change.

28 [SO 4 2- ] Days with no discharge Drier conditions result in higher SO 4 2- concentrations in Ontario, Canada (Eimers and Dillon, 2002)

29 Late Summer/Fall Storms at Archer Creek Low ph related to SO 4 2- mobilization ph Long-Term Avg. Lowest ph LTM Mitchell et al. (2006) 4.7 Inamdar et al. (2004) McHale et al. (2002) Storm # (Study) (LTM = Long-Term Avg.) Mitchell et al. Biogeo. (2006)

30 Effects of Acid Rain (Atmospheric Acidic Deposition) Historical Patterns of SO 2 emissions Linkages to surface water chemistry Watershed sulfur budgets Effect of acidic deposition in China Importance of nitrogen Global Climate Change Importance of climate change in East Asia General impacts Effects on monsoonal rain Melting of Himalayan glaciers Permafrost in Mongolia Nitrogen and snow in northern Japan (Hokkaido) Concluding Statements

31 Major Risks in Asia from Climate Change- IPCC 2007 and certainty Very High, High, Medium, Low, Very Low Permafrost degradation from global warming will increase the vulnerability of many climatedependent sectors affecting the economy in boreal Asia. *** Surface runoff will increase during spring. Summer periods will become more pronounced in boreal Asia. *** The frequency of forest fires will increase in boreal Asia. The large deltas and coastal low-lying areas of Asia will be inundated by sea-level rise. ****

32 Major Risks in Asia from Climate Change (continued) Developing countries of temperate and tropical Asia are vulnerable to droughts and floods; climate change and its variability will make this worse. **** Increased precipitation intensity, particularly during the summer monsoon, will increase flood-prone areas in temperate and tropical Asia. There is a potential for drier conditions in arid and semi-arid Asia during summer and more severe droughts. *** Freshwater availability is expected to be highly vulnerable to climate change.. **** Tropical cyclones will become more intense. Combined with sea-level rise, this will result in loss of life and properties in coastal low-lying areas of cyclone-prone countries of Asia ***

33 Major Risks in Asia from Climate Change (Continued) Crop production and aquaculture will be threatened by thermal and water stresses, sea level rise, increased flooding, and strong winds associated with intense tropical cyclones.*** Warmer and wetter conditions will increase potential for the higher incidence of heatrelated and infectious diseases in tropical and temperate Asia.* Climate change will make worse threats to biodiversity resulting from land-use/cover change and population pressure in Asia..*

34 Some recent results already show that southeast Asia is getting drier RegCM3 simulated interannual variation in precipitation index (mm/day) for two modeled periods. Precipitation index defined as the departure of rainfall from the climatological mean ( ), averaged over land points between 70 90E and 5 25N. From Ashfaq et al. (2009) GEOPHYSICAL RESEARCH LETTERS

35 Glaciers are melting in the Himalayas threatening water supplies to Asia From: Kulkarni et al. (2007) Current Science

36 Lake Hovsgol Mongolia

37 Lake Hövsgöl, Mongolia ( Clive Goulden Philadelphia Academy of Natural Sciences

38 Khusvgul in winter

39 Long-Term Climate Change of the Hovsgol Basin Area Year Temperature,0C Temperature,0C Gradual warming has occurred since the 1970s in Hovsgol area that is similar to reported changes throughout the southern Siberian region. Year Hanh Temperature,0C Murun Year C Hatgal

40 Hövsgöl is in transition zone for permafrost

41 Northern Japan Hokkaido Island Christopher et al.

42 Japan Hokkaido Uryu 1300 km Tokyo Shibecha

43 Long-term changes in maximum snowpack depth in Hokkaido University's Uryu Experimental forest located in northern Japan (Shibata et al., unpublished data, while mostly reported for data from 1956 to 1989 by Hokkaido University Forests 1990). The open circles represent data of each year. The line represents five year's mean which indicates significant decreasing with year (p<0.001).

44 Measured soil temp. and frost depth Uryu More Snow Less Snow Shibecha

45 Snow depth at sites in western versus eastern Hokkaido More Snow Less Snow

46 Snowmelt important period of solute export west Hokkaido Biogeochemical processes occurring under the snowpack vary in Shibecha vs. Uryu µmol L -1 NO Yearly Mean Uryu Shi µmol L -1 NO 3 - µmol L -1 NO /1/00 1/1/01 3/1/01 5/1/01 7/1/01 9/1/01 11/1/ Temporal Pattern Uryu Lower Conc. Shibecha Higher Conc. 0 11/1/01 1/1/02 3/1/02 5/1/02 7/1/02 9/1/02 11/1/02 Uryu unpublished data (Hashiba et al. 2005) Shibecha unpublished data (Nakagawa et al. 2005)

47 Effects of Acid Rain (Atmospheric Acidic Deposition) Historical Patterns of SO 2 emissions Linkages to surface water chemistry Watershed sulfur budgets Effect of acidic deposition in China Importance of nitrogen Global Climate Change Importance of climate change in East Asia Concluding Statements

48 Concluding Statements Acidic deposition has had major impacts on forested watersheds in the northern hemisphere. Emissions decreasing in Europe and North America. Emissions increasing in Asia but at a lower rate than previously predicted. The relative importance of nitrogen versus sulfur in acidic deposition is increasing. Global climate change is clearly documented in Europe, North America and Asia. These climatic effects vary among regions but include documented changes in both hydrology, chemistry and biota. Climatic changes and linkages with ecological changes will be very pronounced in Asia.

49 Domo arigato Xie xie Danyavad Gracias Thank you!