Spaceward Bound:Mojave Expedition

2nd Online Training Session

February 13, 2007

Welcome !!!

Science Themes

1. Desert soil: Soil microbiology, soil oxidants, and soil formation.

2. Geology: Volcanoes, rocks, Amboy crater, Cima lava flows and geology.

3. Photosynthesis: desert hypolithic algae, cyanobacterial soil crusts, and stromatolites.

4. Caves and lava tubes, paleolakes, and remote sensing

Agenda• Introduction (Liza)• Science (Chris, Jim, Henry)

– Photosynthesis (Theme 3)• Hypolithic algae under stones• Photosynthetic layers in Badwater salt mat• Stromatolites of the Crystal Springs Formation

– Soil microbiology (Theme 1)• Transect: dry to wet• Soil microbiology studies• Modeling of soil physics and water state to correlate with

microbiology• Soil organic analysis

• Wrap up and Homework !!!

On the phone

• Dr. James Nienow– Valdosta State University,

Valdosta, GA– jnienow@valdosta.edu

• Dr. Henry Sun– Desert Research Institute,

Las Vegas, NV– henry.sun@dri.edu

Spaceward Bound MojaveScience Themes

• Photosynthesis- hypolithic cyanobacteria- salt mats- stromatolites

• Soil Microbiology- microbial number- life/dead ratios- soil organics & oxidants

Photosynthesis

• Photosynthesis is the ultimate base for virtually all ecosystems

• Life on the surface is Mars = Is there photosynthesis on the surface of Mars

• We are studying photosynthesis in dry and cold environments (Mars-like)

What is a hypolith?

0

20

40

60

80

100

120

23 24 25 26 27 28 29 30 31

Latitude

Mean Annual Rainfall (mm)

-5

0

5

10

15

20

25

30

Percent Colonization

A

R

d=3(2)t=2,600

d=6(5)t=600

d=9(7)t=modern

d=8(5)t=modern

Colonized Stones in the Atacama Desert

Warren-Rhodes et al. Micro. Ecol. 2005

Microbial mat from Badwater salt flats in Death Valley

Wierzchos etal 2006.

Stromatolites from the Crystal Springs carbonate formation from the Mojave Desert. Evidence of photosynthesis over a billion years ago.

Soil Microbiology

• Microbial number and diversity variations from dry to wet- culture methods- non culture methods

• Live/dead ratios and turnover rates

• Presence of organic material in soils

• Presence of oxidants in soils

Hyperarid, < 1 mm/yr

5 mm/yr

25 mm/yr

Mars-like soils in the Atacama Desert; compare Mojave

• Organics drop to low levels in the arid core.

• Oxidized organics increase in relative concentration

• Places with no culturable microorganisms

• Places with no recoverable DNA

• Abiotic consumption of organic material

Viking 2 lander:water frost on Mars

Mars-like soils?

The Viking Biology Experiments

Upcoming Events• Training

– 2 more• Wed., Mar. 7, noon PST

– Two of the science themes– More logistics and Q & A

• Wed., Mar. 21, noon PDT– Final preparations

– Goal• By the end of the training broadcasts you each will be

able to decide whether you want to focus on only one or sample them all

– Homework !!!

Homework p.1Read:• On Spaceward Bound Resources page under

Interesting Readings:– “Desert Landforms and Surface Processes in the

Mojave National Preserve and Vicinity”– “The camels of the prokaryotic world”– “Levels of Bacterial Community diversity in Four Arid

Soils Compared by Cultivation and 16S rRNA Gene Cloning”

– On the web:• http://lsweb.la.asu.edu/fgarcia-pichel

– Click on Research on the bottom of the page

• http://www.soilcrust.org (USGS)

Homework p.2Write a letter to your teacher leader

– Tell him/her about your class and your school• Include the good things and the bad things• Go deeper than just “I teach 6th grade science.”

– Tell him/her:• What you are looking forward to during the

expedition• What’s you’re worried/unsure about

Spaceward Bound:Mojave Expedition

2nd Online Training Session

February 13, 2007

Thanks for joining us