Plant Derived Mineral Bodies as Ecological, Geobiological and Climatic Indicators: A Look at NM Plant Communities

K.D. Morgan-Edel1,2, M.N. Spilde3, and P.J. Boston1,2

1 Earth & Environmental Sciences Dept., New Mexico Institute of Mining & Technology, Socorro, NM 87801

2 National Cave & Karst Research Institute, Carlsbad, NM 882223 Institute of Meteoritics, University of New Mexico, Albuquerque, NM 87131

The Team

Mike Spilde

Mineralogy/Geology

SEM/Microprobe K. Daisy Morgan EdelBiology/EcosystemsGeochemistry

Penny BostonGeomicrobiologyExtreme EnvironmentsKarst Hydrology

Living Organisms Make Inorganic Minerals

Sea shellsBonesTeethDiatomsSponge spiculesCoralRadiolariansPhytoliths

Equisetum Sp.

Flower Coral (Natgeo)

Radiolarian

Phytolith Life CycleFire releases phytoliths

Phytoliths are released during plant decay

Plants take up minerals from the soil. The biominerals made by the plant put minerals back into the soil when released.

Phytoliths are deposited with sediments in the cave during flood events.

Aeolian transport

Si, Al, Ca, etc

Silica Chemistry● Monosilicic Acid (H4SiO4) dissolved in

groundwater● Absorbed by plant roots actively and/or

passively● Bioavailability affected by soil pH and

presence of Fe and Al oxides● High ET rates can force aerial deposition in

some plants● Silica minerals (non-crystalline) dissolve

rapidly in pH > 9● The presence of Al in silica phytoliths slows

dissolution

Silica Morphologies

Giant Sacaton Sporobolus wrightii

Ananas comosus leaf Helianthus maximiliani leaf Morus alba leaf

Achillea millefolium flower

Calcium, it's everywhere!

● Ubiquity in lower and higher plants● Root tips uptake Ca2+ ions from soil● Ca bioavailability is limited by pH < 7,

presence of other competitive ions and minerals eager to bind with Ca ions

● Major calcium plant functions are protection, heavy metal sequestration, and Ca regulation (Franceschi and Nakata 2005)

● Calcic horizons in desert soils● Cacti (Hartl et al 2007); most plants in this

study (crystalline minerals)

Calcium Morphologies

Tamarix ramosissima leaf

Yucca baccata leaf Yucca elata fiber

Opuntia Sp. pad

Larrea tridentata wood

Larrea tridentata leaf epidermal tissue

North American Deserts

Great BasinChihuahuanSonoranMojave

Precipitation EventsElevationTemperatureRain ShadowGeomorphology

Chihuahuan Desert

Agave lechuguilla

Sonoran Desert

Carnegiea gigantea wood 20 micronsParkinsonia florida stem

Riparian ZonesPerennial and ephemeral sources, flood pulsingGeomorphologyEvaporites, halophytesPhreatophytes Tamarix ramosissima

Equisetum Sp. along Rio Bonito, NM

Ephedraceae

● Ubiquitous in the fossil record with well preserved specimens including pollen

● Gnetophyta (70 sp in 3 families) vessel elements

● Diverse and dominant during Tertiary; genus is lone survivor

● present in all four NA deserts

Discussion

● Calcium phytoliths an adaptation to desert soils? Other biominerals?

● What are the optimal conditions for preservation of phytoliths and recovery?

● How does transport mechanically weather the mineral body morphologies?

● Biosignatures?● Applications

Future Work

● Methods● Mineralogy● Cave sediments● Mojave and Great

Basin Desert● Growing conditions ● Mechanical

weathering exp

Acknowledgements● National Cave and Karst Research Institute (NCKRI)● Bureau of Land Management (BLM)

-Jim Goodbar, Mike Bilbo, & other staff● Fort Stanton Cave Study Project (FSCSP)

- Steve Peerman, Wayne Walker, Garrett Jorgensen for cave fieldwork collection

● Stas Edel for field and photography assistance● Virgil Lueth, NMT Mineral Museum● USDA Forest Service & Jason Walz ● Peter Breslin for Sonoran photos

Questions???

Snowy River calcite