Sec on 3: Mechanisms of influence: Basic ecology

Transcription

1 Sec on 3: Mechanisms of influence: Basic ecology Learning outcomes A er this sec on, you should be able to: understand the mechanisms by which temperature and moisture influence plants and animals describe adaptations of plants and animals that allow them to live in suboptimal environments 1

2 Environmental Gradients Different plants have different climate factors Pinus ponderosa Pinus ponderosa Pseudotsuga menziesii Pseudotsuga menziesii McKenzie et al.,

3 Environmental Gradients Range and density MacDonald,

4 Temperature Slide courtesy of C. Still 4

5 Temperature 0 deg C for >24 hours Temperature and the saguaro cactus (Carnegiea gigantea) Frost damage in 1962: More than 12 to 24 hours below freezing damages the plant Lomolino et al.,

6 Temperature 6 Slide courtesy of C. Still

7 Temperature Animals: Temperature effects on distributions 7

8 Temperature Animals: Temperature adaptations to cold Migration North-south Higher-lower 8

9 Temperature Animals: Temperature adaptations to cold Physiology Cold hardening of mountain pine beetle Decrease of supercooling point as winter progresses 9 Bentz and Mullins, 1999

10 Temperature Animals: Temperature adaptations to heat Shelter homepages.gac.edu/~cjgroh/classes/tzpictures.html Lomolino et al

11 Temperature Animals: Temperature adaptations to heat Morphology Cool adaptations to hot conditions Elephant (Loxodonta africana) Chameleons (Chamaeleo) fohn.net/elephant-pictures-facts 11

12 Temperature Temperature affects sex ratio of turtle hatchlings Implications of global warming? Bull and Vogt,

13 Moisture Soil moisture controls on woody plants in desert Southwest Lomolino et al

14 Moisture Moisture stress on plants: mortality Croplands Pinyon pine in SW Photo by Craig Allen - USGS 14

15 Moisture Soil moisture controls on tree species distribution in PNW Barnes et al.,

16 Moisture Rooting depth in arid landscape controls species distribution Elmore et al.,

17 Moisture Controls of soil moisture at larger scale 17 Friedl et al.

18 Moisture Controls of soil moisture at larger scale Precip Biomass Veg type dry wet none high none shrublands savannas dense forest dry none 18 Friedl et al.

19 Moisture Plant strategies to deal with drought: 1. Escapees Perennials (dormancy) Annuals ( emphemerals ) 19

20 Moisture Plant strategies to deal with drought: 2. Avoiders Slide courtesy C. Still 20 DeFries et al., 2000

21 Moisture Plant strategies to deal with drought: 2. Avoiders Slide courtesy C. Still 21

22 Moisture Adaptations to low water availability Namib Desert beetle (Onymacris unguicularis) morphology adaptations to capture fog: bumps on back channels to mouth head down behavior can capture 40% of body weight in one morning

23 Multiple factors/interactions What factors limit white spruce at its northern and southern extent? Summer temperatures Moisture stress (high summer temps, low precip) 23

24 Multiple factors/interactions Controls on Net Primary Production Nemani et al.,

25 Annual water balance and climatic water deficit Sierra Nevada, CA: Coniferous soil water recharge surplus deficit surplus Water supply PET AET Stephenson,

26 Annual water balance and climatic water deficit Sierra Nevada, CA: Coniferous soil water recharge deficit surplus surplus Water supply (rain+snowmelt) PET AET 26 Stephenson, 1998

27 Annual water balance and climatic water deficit Erie, PA: Deciduous Water supply (rain+snowmelt) PET AET 27

28 Multiple factors/interactions Distribution of major N. America plant formations 28 Stephenson, 1990

29 higher growth Multiple factors/interactions Distribution of major N. America plant formations Energy and water availability AET: separation of different forest types 29 Stephenson, 1990

30 higher growth Multiple factors/interactions Distribution of major N. America plant formations Energy and water availability AET: separation of different forest types Deficit: separation of forest types from prairie Moisture limitation higher growth 30 Stephenson, 1990

31 Multiple factors/interactions Three reasons conifers dominate over deciduous trees energy limited: low PET => low AET/growth Precipitation PET water limited: low precip => low AET/growth AET S = surplus of water (hatched) D = deficit of water (stippled) asynchrony in energy, water supplies => low AET/growth 31 Stephenson, 1990