Cameron, Roy E.

David, Charles N.

King, Jonathan

English

Open Access LMU

BIOLOGY Soil Microbial and Ecological Studies in Southern Victoria Land1 R O Y C A M E R O N , J O N A T H A N K I N G , and CHARLES D A V I D Bioscience Section Jet Propulsion Laboratory California Institute of Technology Since 1961, the Jet Propulsion Laboratory (JPL) has conducted a desert-microflora program involving investigations on several continents of desert environ­ments, soils, and microorganisms relevant to the detection and quarantine of life on Mars. The ob­jectives are to study and identify basic groups of microorganisms of extreme environments, especially those of desert soils, and to correlate the environ-mental parameters with the distribution, abundance, and kinds of microorganisms and their activities. Antarctic dry valleys have been studied during the austral summers of 1966-1967 (Cameron, 1967) and 1967-1968. Five field sites were established for ap­proximately one-week periods, some in cooperation w i t h the Virginia Polytechnic Institute (VPI ) (Benoit and Cameron, 1967). Soil samples were col­lected aseptically from the surface to a level a few inches below the upper surface of permafrost at selected sites throughout the valleys. Measurements o r observations were made either continuously or every three hours of soil temperature, solar-radiation flux, net thermal exchange, ultraviolet-radiation flux, l i ght intensity, wind direction and velocity, baro­metric pressure, evaporation rate, relative humidity, dew point, and gas concentration. Dur ing the past season, 58 surface and subsurface soil samples were collected. Twelve of them were obtained with Dr. James Turnock of NASA, Wash­ington, D.C., for testing at the Lunar Receiving Laboratory. Microbiological analyses of 45 samples f r o m 22 sites were made at the McMurdo biological laboratory. More than 1,000 pounds of frozen sam­ples were sent to JPL's Soil Science Laboratory for further processing and analysis. Sandy, saline soils * This paper presents the results of one phase of research carried out by the Jet Propulsion Laboratory, California I n ­stitute of Technology, under contract Ν AS 7-100, sponsored by the National Aeronautics and Space Administration. Logistic support and facilities for the investigations in Ant­arctica were Arranged by the Office of Antarctic Programs, Rational Science Foundation. that are sometimes high in chlorides, nitrates, and sulfates, but quite low in organic matter, yielded few microorganisms. For the first time i n the study of desert-soil micro­bial ecology, i t was found that the abundance and diversity of microorganisms was greatly dependent upon variations of specific ecologic factors. Unfavor­able environmental conditions, such as east-west val­ley orientation, south-facing slopes, low solar-radia­tion flux, high southerly winds, low humidities, short duration of available water, and salty soils, were ob­served to restrict greatly the existence and activity of microorganisms. A comparison of favorable and un­favorable ecologic factors important for determining the distribution of life in the antarctic dry valleys is shown i n Fig. 1. Under the least favorable conditions, either no microorganisms or only a single population of heterotrophic, aerobic, nonpigmented bacteria was observed. For example, such conditions were observed fAVORABU N-S ORIENTATION NORTHERN EXPOSURE GENTLE, NORTH-FACING SLOPES HIGH SOLAR RADIATION MICROCLIMATE ABOVE FREEZING ABSENCE OF WIND NORTHERLY WINDS HIGH HUMIDITIES SLOW OR IMPEDED DRAINAGE LENGTHY DURATION OF AVAILABLE HjO (PRESENCE OF GLACIERS, LAKES, STREAMS, SNOW AND ICE FIELDS) TRANSLUCENT PEBBLES NON-SALTY SOILS, BALANCED IONIC COMPOSITION APPROX NEUTRAL pH ORGANIC CONTAMINATION (SKUAS, SEALS, ETC) UNFAVORABLE E-W ORIENTATION SOUTHERN EXPOSURE FLAT OR SOUTH-FACING SLOPES LOW SOLAR RADIATION MICROCLIMATE BELOW FREEZING HIGH WINDS SOUTHERLY WINDS LOW HUMIDITIES RAPID DRAINAGE SHORT DURATION OF AVAILABLE Η ? 0 (ABSENCE OF GLACIERS, LAKES, STREAMS. SNOW AND ICE FIELDS) OPAQUE PEBBLES SALTY SOILS, UNBALANCED IONIC COMPOSITION HIGH (OR LOW) pH NO ORGANIC CONTAMINATION (NO LARGE INCREMENTS OF ORGANIC MATTER) Figure /. Ecological factors determining distribution of life in antarctic dry valleys* July-August 1968 121 OffΤΗ. AfROIK «ACTCRIA • ACTINOMYCtT» SURF I 3.7 · »0 1 - 4 20 VJRF ι ο S U « . I 0 4 » 10 1 .* > »0 ? ' 10 7? m I Figure 2. Diversity vs. abundance for surface samples at each soil-collection site in the Asgard Range. • iO'C I Λ • 10 1.7 . I0 S 2 . . 0 1 ANAfROIfS ROOM I IMP su». 1 »·?» »0 ι T R Y F T I C A U S O Y A G A R 5 I ? i! VA»«»I a a u : m ·4>ι·ο«·ο*·< Mrrtn» -SAW (SIMULATED TAYLOR VAll fY SOU EXTRACT) · VIASt CX TRACT « NiormoNi - J FUNGI I AlGAC • 20'C ; ROOM TCMf 2.5 . »0* 3 » I0 2 3 » I0 3 20 . MlCROAEIORMtm 10 J THORNTON'S FLUID SAIT THIOGIVCOILATI MEDIUM (FOSIIIVti OO gm . R I C O R O I O F O R INOCUtUMI HIGHCST I D I L U T I O N ) iMOMU ~. . Mt«r*i* -Figure 4. Variability of population density and diversity tcith variability of ecological factors in antarctic dry valleys. at a!! locations examined by the authors and Prof. Robert Benoit of V P I during a traverse they made cooperatively along the west side of the Matterhorn Glacier from the glacier's head to Lake Bonney in Taylor Valley. The abundances of microorganisms determined for 18 samples are shown in Fig. 3. The maximum total abundance did not exceed 10 5 /g of soil, and some samples contained few or no microorganisms as deter­mined by culture techniques.2 I n three out of every four sites investigated, the subsurface microflora was more abundant than the surface microflora. Nonpig-mented bacteria were generally more abundant than pigmented species and had the ability to grow in a 8 Fifteen antarctic soils were studied by Dr. Jerry Hubbard of the JPL Bioscience Section. Soils were incubated with a substrate mixture containing ,4C-glucose and 1 4C~amino acids. Metabolic 1 < C 0 2 was then determined. The net CPM was found to correlate to a considerable extent with the absence or presence of microorganisms as determined by culture techniques. 122 Figure 3. Microorganisms in Asgard Range soil samples (per gram of soil). wider variety of culture media. Most of the bacterial isolates were Bacillus spp., soil diptheroids, Micro-coccus spp., and Mycocöccus spp. The algae were primarily oscillatorioid and coccoid blue-green forms, including Oscillatoria spp., Microcoleus spp., Schizo-thrix spp., Anacystis spp., and Coccochloris spp. The fungi included a number of ascomycetous molds and some yeasts. Protozoa were of the flagellated or amoeboid forms. No bacteriophages were found. The absence of anaerobes is especially significant since they have not been found in the harshest of other desert soils (such as those of the Sahara and Atacama Deserts) investigated by JPL. The relationship of population diversity and abun-dance of microorganisms in samples obtained from a valley in the Asgard Range is shown in Fig. 2. As indicated in this figure, species diversity and abun-dance increase with the favorableness of ecological conditions. For this valley, as well as for other valleys investigated, i t was predicted and then substantiated that, with a given set of environmental conditions, there would be an ecologic succession as well as a numerical increase in organisms as the environment became more favorable (Fig. 4 ) . Additional antarctic soil samples wil l be analyzed and attempts made to correlate the abundance, dis-tribution, and kinds of microorganisms according to pertinent ecological factors operative in the dry val -leys. For life-detection purposes, whether terrestrial or A N T A R C T I C J O U R N A L extraterrestrial, i t is becoming more evident that the environmental conditions, especially the duration of availability of nonsalty moisture, are extremely i m ­portant for the existence of life in a harsh environ­ment . References Benoit, R. E. and R. E. Cameron. 1967. Microbial ecology of jome dry valley soils of Antarctica. Bacteriological Proceed' ings, Abstracts, A13, p. 3. Cameron, R. E. 1967. Soil Studies—Desert Microflora: XIV, Soil Properties and Abundance of Microflora from a Soil Profile in McKelvey Valley, Antarctica, California Insti» tute of Technology, Jet Propulsion Laboratory, Space Pro­grams Summary 37-44, vol. I V , p. 224-236. July-August 1968 123 

Microbial ecology of jome dry valley soils of Antarctica.

Soil Studies—Desert Microflora: XIV, Soil Properties and Abundance of Microflora from a Soil Profile in McKelvey Valley,

Soil microbial and ecological studies in southern Victoria land

Universität München: Elektronischen Publikationen

BIOLOGY 
Soil Microbial and Ecological Studies in 
Southern Victoria Land1 
R O Y C A M E R O N , J O N A T H A N K I N G , and 
CHARLES D A V I D 
Bioscience Section 
Jet Propulsion Laboratory 
California Institute of Technology 
Since 1961, the Jet Propulsion Laboratory (JPL) 
has conducted a desert-microflora program involving 
investigations on several continents of desert environ­
ments, soils, and microorganisms relevant to the 
detection and quarantine of life on Mars. The ob­
jectives are to study and identify basic groups of 
microorganisms of extreme environments, especially 
those of desert soils, and to correlate the environ-
mental parameters with the distribution, abundance, 
and kinds of microorganisms and their activities. 
Antarctic dry valleys have been studied during the 
austral summers of 1966-1967 (Cameron, 1967) and 
1967-1968. Five field sites were established for ap­
proximately one-week periods, some in cooperation 
w i t h the Virginia Polytechnic Institute (VPI ) 
(Benoit and Cameron, 1967). Soil samples were col­
lected aseptically from the surface to a level a few 
inches below the upper surface of permafrost at 
selected sites throughout the valleys. Measurements 
o r observations were made either continuously or 
every three hours of soil temperature, solar-radiation 
flux, net thermal exchange, ultraviolet-radiation flux, 
l i ght intensity, wind direction and velocity, baro­
metric pressure, evaporation rate, relative humidity, 
dew point, and gas concentration. 
Dur ing the past season, 58 surface and subsurface 
soil samples were collected. Twelve of them were 
obtained with Dr. James Turnock of NASA, Wash­
ington, D.C., for testing at the Lunar Receiving 
Laboratory. Microbiological analyses of 45 samples 
f r o m 22 sites were made at the McMurdo biological 
laboratory. More than 1,000 pounds of frozen sam­
ples were sent to JPL's Soil Science Laboratory for 
further processing and analysis. Sandy, saline soils 
* This paper presents the results of one phase of research 
carried out by the Jet Propulsion Laboratory, California I n ­
stitute of Technology, under contract Ν AS 7-100, sponsored 
by the National Aeronautics and Space Administration. 
Logistic support and facilities for the investigations in Ant­
arctica were Arranged by the Office of Antarctic Programs, 
Rational Science Foundation. 
that are sometimes high in chlorides, nitrates, and 
sulfates, but quite low in organic matter, yielded few 
microorganisms. 
For the first time i n the study of desert-soil micro­
bial ecology, i t was found that the abundance and 
diversity of microorganisms was greatly dependent 
upon variations of specific ecologic factors. Unfavor­
able environmental conditions, such as east-west val­
ley orientation, south-facing slopes, low solar-radia­
tion flux, high southerly winds, low humidities, short 
duration of available water, and salty soils, were ob­
served to restrict greatly the existence and activity of 
microorganisms. A comparison of favorable and un­
favorable ecologic factors important for determining 
the distribution of life in the antarctic dry valleys is 
shown i n Fig. 1. Under the least favorable conditions, 
either no microorganisms or only a single population 
of heterotrophic, aerobic, nonpigmented bacteria was 
observed. For example, such conditions were observed 
fAVORABU 
N-S ORIENTATION 
NORTHERN EXPOSURE 
GENTLE, NORTH-FACING SLOPES 
HIGH SOLAR RADIATION 
MICROCLIMATE ABOVE FREEZING 
ABSENCE OF WIND 
NORTHERLY WINDS 
HIGH HUMIDITIES 
SLOW OR IMPEDED DRAINAGE 
LENGTHY DURATION OF AVAILABLE HjO 
(PRESENCE OF GLACIERS, LAKES, STREAMS, SNOW 
AND ICE FIELDS) 
TRANSLUCENT PEBBLES 
NON-SALTY SOILS, BALANCED IONIC COMPOSITION 
APPROX NEUTRAL pH 
ORGANIC CONTAMINATION 
(SKUAS, SEALS, ETC) 
UNFAVORABLE 
E-W ORIENTATION 
SOUTHERN EXPOSURE 
FLAT OR SOUTH-FACING SLOPES 
LOW SOLAR RADIATION 
MICROCLIMATE BELOW FREEZING 
HIGH WINDS 
SOUTHERLY WINDS 
LOW HUMIDITIES 
RAPID DRAINAGE 
SHORT DURATION OF AVAILABLE Η ? 0 
(ABSENCE OF GLACIERS, LAKES, STREAMS. SNOW 
AND ICE FIELDS) 
OPAQUE PEBBLES 
SALTY SOILS, UNBALANCED IONIC COMPOSITION 
HIGH (OR LOW) pH 
NO ORGANIC CONTAMINATION 
(NO LARGE INCREMENTS OF ORGANIC MATTER) 
Figure /. Ecological factors determining distribution of life 
in antarctic dry valleys* 
July-August 1968 
121 
OffΤΗ. 
AfROIK «ACTCRIA • ACTINOMYCtT» 
SURF I 3.7 · »0 
1 - 4 20 
VJRF ι ο 
S U « . I 0 
4 » 10 
1 .* > »0 ? 
' 10 7? m 
I 
Figure 2. Diversity vs. abundance for 
surface samples at each soil-collection 
site in the Asgard Range. 
• iO'C 
I Λ • 10 
1.7 . I0 S 
2 . . 0 1 
ANAfROIfS 
ROOM I IMP 
su». 1 »·?» »0 
ι T R Y F T I C A U S O Y 
A G A R 
5 
I 
? 
i! 
VA»«»I a a u : m 
·4>ι·ο«·ο*·< Mrrtn» -
SAW (SIMULATED 
TAYLOR VAll fY 
SOU EXTRACT) · 
VIASt CX TRACT « 
NiormoNi 
- J 
FUNGI I AlGAC 
• 20'C ; ROOM TCMf 
2.5 . »0* 3 » I0 2 
3 » I0 3 20 
. MlCROAEIORMtm 
10 J 
THORNTON'S FLUID 
SAIT THIOGIVCOILATI 
MEDIUM (FOSIIIVti 
OO gm . R I C O R O I O F O R 
INOCUtUMI HIGHCST 
I D I L U T I O N ) 
iMOMU 
~. . Mt«r*i* -
Figure 4. Variability of population density and 
diversity tcith variability of ecological factors in 
antarctic dry valleys. 
at a!! locations examined by the authors and Prof. 
Robert Benoit of V P I during a traverse they made 
cooperatively along the west side of the Matterhorn 
Glacier from the glacier's head to Lake Bonney in 
Taylor Valley. 
The abundances of microorganisms determined for 
18 samples are shown in Fig. 3. The maximum total 
abundance did not exceed 10 5 /g of soil, and some 
samples contained few or no microorganisms as deter­
mined by culture techniques.2 I n three out of every 
four sites investigated, the subsurface microflora was 
more abundant than the surface microflora. Nonpig-
mented bacteria were generally more abundant than 
pigmented species and had the ability to grow in a 
8 Fifteen antarctic soils were studied by Dr. Jerry Hubbard 
of the JPL Bioscience Section. Soils were incubated with 
a substrate mixture containing ,4C-glucose and 1 4C~amino 
acids. Metabolic 1 < C 0 2 was then determined. The net CPM 
was found to correlate to a considerable extent with the 
absence or presence of microorganisms as determined by 
culture techniques. 
122 
Figure 3. Microorganisms in Asgard Range soil samples (per gram of soil). 
wider variety of culture media. Most of the bacterial 
isolates were Bacillus spp., soil diptheroids, Micro-
coccus spp., and Mycocöccus spp. The algae were 
primarily oscillatorioid and coccoid blue-green forms, 
including Oscillatoria spp., Microcoleus spp., Schizo-
thrix spp., Anacystis spp., and Coccochloris spp. The 
fungi included a number of ascomycetous molds and 
some yeasts. Protozoa were of the flagellated or 
amoeboid forms. No bacteriophages were found. The 
absence of anaerobes is especially significant since 
they have not been found in the harshest of other 
desert soils (such as those of the Sahara and Atacama 
Deserts) investigated by JPL. 
The relationship of population diversity and abun-
dance of microorganisms in samples obtained from 
a valley in the Asgard Range is shown in Fig. 2. As 
indicated in this figure, species diversity and abun-
dance increase with the favorableness of ecological 
conditions. For this valley, as well as for other valleys 
investigated, i t was predicted and then substantiated 
that, with a given set of environmental conditions, 
there would be an ecologic succession as well as a 
numerical increase in organisms as the environment 
became more favorable (Fig. 4 ) . 
Additional antarctic soil samples wil l be analyzed 
and attempts made to correlate the abundance, dis-
tribution, and kinds of microorganisms according to 
pertinent ecological factors operative in the dry val -
leys. For life-detection purposes, whether terrestrial or 
A N T A R C T I C J O U R N A L 
extraterrestrial, i t is becoming more evident that the 
environmental conditions, especially the duration of 
availability of nonsalty moisture, are extremely i m ­
portant for the existence of life in a harsh environ­
ment . 
References 
Benoit, R. E. and R. E. Cameron. 1967. Microbial ecology of 
jome dry valley soils of Antarctica. Bacteriological Proceed' 
ings, Abstracts, A13, p. 3. 
Cameron, R. E. 1967. Soil Studies—Desert Microflora: XIV, 
Soil Properties and Abundance of Microflora from a Soil 
Profile in McKelvey Valley, Antarctica, California Insti» 
tute of Technology, Jet Propulsion Laboratory, Space Pro­
grams Summary 37-44, vol. I V , p. 224-236. 
July-August 1968 
123 


http://epub.ub.uni-muenchen.de/3440/1/3440.pdf

Soil microbial and ecological studies in southern Victoria land

Abstract

Similar works

Full text

Available Versions

Open Access LMU

Universität München: Elektronischen Publikationen