Transcript Chauhan_NCCSD COnference_2014

The Vital Soil Microbiome and
Impacts of Climate Change
Ashvini Chauhan, Ph.D.
Associate Professor
Environmental Biotechnology and Genomics Laboratory
School of the Environment, 1515 S. MLK Blvd.,
Suite 305B, FSHSRC, Florida A&M University,
Tallahassee, FL-32307, USA
[email protected]
Florida A&M University (FAMU)
The School of the Environment (SoE)
• SoE is one of several innovative programs in the STEM
disciplines at FAMU offering BS, MS and Ph.D. degrees in
environmental sciences and policy.
• Home to 10 faculty and 80 students in all degree programs.
• Several new cutting-edge programs are being developed:
• BS in environmental studies
• PSM in environmental biotechnology
• Ph.D. concentration track in environmental laws
• Research activities supported by state funds, grants and contracts.
Research Interests
1. Responses to environmental microorganisms by anthropogenic impacts, such as
global warming;
2. Sustainable solutions for contaminant cleanup using microbially-mediated
biodegradation technologies;
3. Sustainable production of cyanobacteria and microalgal based biofuels and other
value-added products;
4. Bacterial genomics and metabolomics to better understand the genomic, catabolic
and metabolic potential of environmental microorganisms
Jesse Thomas
Devin Alvarez
Denis Wafula
Devin Alvarez
Lowell Collins
Claire Smith
Ashish Pathak
Why are Microorganisms so Important
to the Environment?
• Microbes make up most living matter (~60% of the
earths biomass)
• Up to 1 billion cells/g of soil>>maintain soil fertility
• Microbes degrade pollutants, generate at least half
the oxygen we breathe, fix atmospheric nitrogen for
plants and recycle carbon, phosphorus, iron and even
water!
• Bacterial biomass is the basis of marine and
freshwater food webs
• Without microorganisms, life would cease to exist…
Microbes are Everywhere and Live Together
http://www.da
nmarco.net/m
ultipoint/biofi
lm.htm\
In human oral biome
http://www.hypertextbookshop.com/biofilmbook/working_version/index.html
With plant
roots
and with others…..In cow rumen
In oyster guts
In corals
(Chauhan et al., Under
preparation)
In lichens
In human guts
In squids
In termite guts
Human Microbiome Project
Ecological Diversity
-Salinity: Fresh water to marine and hypersaline environments (Dead sea and the
Great Salt Lake, halophiles can tolerate 5-times the salt found in oceans
-Temperature: from –12 (chryophiles) to 113oC to 121oC) (thermophiles)
-pH: from 0 to 13 pH
- Redox Potential: from –200mV
(methanogens) to +600mV
- Hydrostatic Pressure: from 1 to 1400
atm (barophiles)
Metabolic Diversity
Phototrophs: Energy is obtained from light
• Heterotrophs: carbon is obtained from organic compounds
(halophilic Archaea and several bacteria)
• Autotrophs: carbon is obtained by fixing
CO2 (most cyanobacteria, photosynthetic
bacteria)
http://arctida.blogspot.com/2010/11/cyanobacteriaasymmetric-contemporary.html
Chemotrophs: Energy is obtained from
chemicals
• Lithotrophs: Inorganic chemicals
(sulfur, iron, hydrogen)
• Organotrophs: carbon and energy are
obtained from organic chemicals
(E.coli, pathogens)
http://ncassyellowstone.wordpress.com/pictures/
Latest Research Suggests that…
Based on 4 Generalizations:
(1) All animals and plants establish symbiotic relationships with
microorganisms
(2) The association between host and symbionts affects the
fitness of the holobiont within its environment
(3) Variation in the hologenome can be brought about by changes
in either the host or the microbiota genomes
(4) Under environmental stress, the symbiotic microbial
community can change rapidly
"The role of the infinitely small
in nature is infinitely large"
-Louis Pasteur
Many Soil Bacteria Enhance Plant
Productivity
Rhizosphere
Bulk
Soil
Efficient Microorganisms:
EM™ stands for "Effective
Microorganisms™" developed by
Professor Dr. Teruo Higa from Japan.
EM™ consists of a wide variety of
effective, beneficial and non-pathogenic
microorganisms produced through a
natural process and not chemically
synthesized or genetically engineered that
is shown to enhance plant productivity.
Rhizonify™ is a formulation from Grigg
Brothers designed to facilitate the
interaction of turfgrass roots with water,
nutrients, and sugars in the rhizosphere to
improve rooting, enhance plant energy
status, and promote turfgrass vigor in
challenging soil conditions or during
environmental stress.
Intergovernmental Panel on Climate Change
(commissioned by UN) "most of the warming observed
over the last 50 years is attributable to human activities".
Blame is on
primarily
on CO2
emissions
GCC and Microbes
GCC are likely to affect soil microbial
processes by:
• Altering the function of environmental
microorganisms
• Restructuring the community
• Modifying the physiologies of microbes
that drive biogeochemical processes
GCC Will Influence Soil
Productivity:
Directly:
- Affecting the growth, survival and dispersal of soil
organisms
- Changing decomposition rates and C and N cycling
Indirectly:
- Influencing plant productivity and litter fall rates and
root turnover and soil organic matter
-Changing substrate chemistry
-Changing plant species composition
Free-Air CO2 Enrichment (FACE) provides a unique opportunity
Four FACE rings
surrounding deciduous
forest trees at the Oak
Ridge National
Laboratory.
- These FACE research facilities give scientists an opportunity to
understand how different plant biochemical, physiological, and growth
processes within the ecosystem will respond as a result of long-term
exposure to elevated CO2 levels.
- The FACE studies are designed to address the question of how
ecosystems will respond to future atmospheric CO2 environments and
whether the growth response level off at some future CO2 level.
Conclusions
• It is difficult to draw general conclusions
about the full effects of elevated CO2 on
terrestrial ecosystems.
• Elevated (CO2) has adverse effects on
microbial
community
structure
and
microbial activity.
• Simulated climate change reduced species
number, richness and diversity.
Recommendations
- Climate change is global and thus the impacts of
global warming on plants and their native microbiota
needs to be studied at a global level
- Integrated international teams need to work
seamlessly on the many facets of global warming
and climate smart environmental practices
- A holistic understanding on effects of climate change
on plant’s aboveground and belowground forces
need to be studied in further details.