Simplistic predictions, confounding effects, and complex responses; climate tales from Archbold Biological Station

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Terence Merritt
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1 Simplistic predictions, confounding effects, and complex responses; climate tales from Archbold Biological Station Hilary Swain 1, Nancy Deyrup 1, Kye Ewing 1, Evelyn Gaiser 2, Reed Bowman 1 & Eric Menges 1 1 Archbold Biological Station 2 Florida International University

2 Archbold Biological Station founded 1941 data collection from 1931

4 Eric C. Grimm Illinois State Museum Research and Collections Center

5 2001 Higher summer temperatures, decrease in winter cold spells, shift north in frost line, earlier breeding for plants and animals Warming of lakes Increases in drought related fires

6 Maximum summer temperatures (J,J,A) Maximum midwinter temperatures (D,J,F)

7 Summer minimum temperatures (J,J,A) Midwinter minimum temperatures (D,J,F)

Number of freeze days at Archbold 24 22 20 18 16 14 12 10 8 6 4 2 0

1971-1972 1976-1977 1981-1982 1986-1987 1991-1992 1996-1997 2001-2002

8 Number of freeze days at Archbold Archbold Temp change in relation to land use change- Marshall

9 Lake Istokpoga

10 Long-term climate trends in timing of breeding in Florida Scrub-Jays? Unclear - except breed earlier during La Nina Mean laying date (day of year) el nino Year la nina all years supplemented not supplemented Reed Bowman Laying date Southern Oscillation Index (SOI) Reed Bowman

11 Marked land use effect on timing of breeding in suburban versus Archbold Scrub jays 1 March 1 April 1 May 1993 natural suburban natural suburban natural suburban natural suburban natural suburban natural suburban natural suburban natural suburban First clutch initiation (Julian date) Reed Bowman

12 2001 Warming of lakes test using Lake Annie long-term datasets from Archbold

13 Lake Annie: decreasing temperature over time 12 Mo. Running Mean T (ºC) Mean Water T (ºC) Air T Water T Surface Bottom Stage (FSL) Min Ann. 1% Light (m) Groundwater Level Lake Stage Lake 2 Stage 4 R 2 = Groundwater 10 Level R 2 = Increased stage and groundwater height are associated with decreased transparency Gaiser et al in prep

14 80 70 Precipitation (Jun-Oct) Precipitation (Nov-May) Annual rain above/below average (52.87") AMO warm AMO cool warm Inches rain

15 2001 Increases in drought related fires

16 Increasing fires in relation to drought? Archbold - acres burned annually 47% prescribed, 35% accidental, 18% lightning Prescribed/Escape Prescribed Lightning Accidental Dry season rainfall driven by ENSO Dry season rainfall (inches) Southern Oscillation Index

17 Prescribed fires acres in relation to drought KBDI Acres Accidental fire acres in relation to drought KBDI Acres Lightning fire acres in relation to drought KBDI Acres

18 Climate change and plants Eric Menges In Florida, predictions of more variable climate NCEAS group: explore different types of variation and effects on stochastic growth rate (Morris et al. 2007, Ecol. Letters) 3 of 5 species in analysis from Florida scrub (data from Menges et al., ABS plant lab) Expectation from past studies: variation reduces stochastic growth rate

Positive elasticities for between-phase variance, especially for survival (left group of bars), for D. frutescens 0.1 0-0.1-0.

19 Positive elasticities for between-phase variance, especially for survival (left group of bars), for D. frutescens Greater demographic variation between, rather than within time-since-fire phases Positive elasticities for between-phase demographic variance Implies adaptation to fire-driven disturbance regime Also implies that climate-change effects on plants will be mediated by effects on disturbance regime (e.g. will there be increased fire frequency given more variable climate?)

20 No good support for our simplistic predictions - plenty of confounding effects, and complex responses Land use change Wetland losses, urbanization AMO and SOI drivers Overwhelming drivers for intermediate (20-30year) and short term drought and flooding cycles Socio-economic responses - burn permits, FSJ supplementary feeding Recommend a return to Lake Annie for a detailed year core to elucidate a decadal resolution climate record Team of researchers very interested in such an undertaking.

REMINDERS: UPCOMING REVIEW SESSIONS: - Thursday, Feb 27, 6:30-8:00pm in HSS 1330

REMINDERS: UPCOMING REVIEW SESSIONS: - Thursday, Feb 27, 6:30-8:00pm in HSS 1330 REMINDERS: Midterm 2: Friday, February 28 - lecture material covering chapters 6, 7, and 15 (since first midterm and through Wed lecture) - same Format as first midterm UPCOMING REVIEW SESSIONS: - Thursday,