Jennifer Moore-Kucera

1. Phylogenetic Changes in Soil Bacterial
and Fungal Communities in Land under
CRP and during Conversion to Cropland
PI: Jennifer Moore-Kucera,
Co-PIs: Veronica Acosta-Martinez
John Zak, Juske Horita,
Franciso Calderon, David Weindorf
Ph.D. students: Mamatha Kakarla, Chenhui Li,
Former post-doc: Lisa Fultz
Depart of Plant & Soil Science
Depart of Biological Sciences
Dept of Geosciences
Award #:
2012-67019-30183

2. nual row crops
7 fields
Rangeland
3 fields
CRP
16 fields
Objective 1:
ective 1: Evaluate soil microbial and quality
nges with increasing time under CRP restoration
>50Early: 6-15 yrs restored
Late: 20-26 yrs restored
yrs
estored
26 fields sampled across 7 Texas High Plains Counties
Sampled in 2012 (5.7% H2O) and 2014 (14% H2O)
Target soil series: Amarillo fine sandy loam
Soil: Amarillo fine sandy loam
pH: 7.6 (0-30cm)

3. Soil Restoration following Disturbance
Ecosystem
Disturbance
Original
Ecosystem
Long-term
ow crops
Early
CRP
Late
CRP
Rangeland

4. reased restoration time increased nutrient
ling potential and decreased metabolic stress
Metabolic quotientzymatic activity
MBC/CO2
with positive correlation:

5. Time Under Restoration Not Significant Driver of
Soil Bacterial Composition
Cropped fields:
Proteobacteria,
Firmicutes, Bacteroidetes,
Nitrospirae, and
CRP & Rangeland:
Rubrobacteria,
Acidobacteria,
Verrucomicrobia,
Chlorobi, Fibrobacters
and Planctomycetes

6. Verrucomicrobia and Planctomycetes:
Key taxa involved in soil organic matter?
anctomycetes, Verrucomicrobia, and Rubrobacteria
y = 4.1x - 0.57
R = 0.744**
0
5
10
15
20
25
30
35
0.0 2.0 4.0 6.0 8.0
Soilorganicmatter(gkgsoil)
Verrucomicrobia (%)

7. Microbial Network Analysis:
Rare Microbiome Differentiate Management
Common OTUs bring nodes
or samples together  No
Distinct OTUs repel nodes
Long-term
croplands
Early CRP
(6-14y)
Late CRP
(21-26y)
Abundant Microbiome
(counts are 1700 or more):
Rare Microbiome
(counts are 5-10)

8. Soil Fungal Community More Sensitive to
Restoration Time Than Soil Bacterial Community

9. j 1 Conclusions
urrent conservation contracts may not be long
nough to realize optimal ecosystem functions
oil bacterial communities were not affected by
estoration time but were distinct from croplands.
Rare” bacterial biome may provide more insight
oil fungi were more sensitive to time under
estoration than bacteria
acterial taxa were identified that may play key

10. Objective 2: What happens to the soil
ecosystem when CRP land is converted?
Ecological Benefits:
Reduced soil erosion
Improved water, air,
soil quality
?

11. Converted CRPCRP
aluate short-term changes in soil quality and
crobial dynamics after CRP conversion
Main plot: System (CRP vs. Converted)
Split: 3 depths (0-10, 10-30, 30-50cm)
Block: 3 counties
Sampling: Fall 2012, 2013, 2014
23-25 yrs enrolled 22-25 yrs enrolled
(converted 2010 or 2012)
Soil texture: Fine sandy loam
pH: 7.6 (0-30cm)
SOM: 1.4%
plit-plot
RCB:

12. 10-30cm: Converted fields had greater bacterial
cies richness and diversity measures in
P and converted CRP fields
Phylogenetic diversity indexSpecies Richness
Phylogeneticdiversityindex
p<0.0001p<0.0001
Converted
CRP
CRP Converted
CRP
CRP
10-30cm
10-30cm
10-30cm
10-30cm

13. nverted CRP fields associated with a
istribution of SOM
Initial SOM
incorporation provides
flux of resources to
bacteria  promotes
bacterial diversity
Converted
CRP
CRP
10-30cm
10-30cm
Soil organic C

14. nversion of CRP back to crop systems altered
terial communities in both depths
p<0.001
0-10cm
0-10cm
10-30cm
10-30cm
Converted
CRP
CRP
Bacterial communities

15. nversion of CRP back to crop systems altered
terial communities in both depths
0-10cm
0-10cm
10-30cm
10-30cm
Converted
CRP
CRP
CRP Greater:
Verrucomicrobia
(18%)
Cyanobacteria
(58-80%)
Rubrobacteria
(40%)
Acidobacteria
Converted Greater:
γ-proteobacteria
(49-62%)
β-proteobacteria
(74-97%)
Gemmatimonadetes
(104-138%)
Firmicutes
(20-36%)

16. reduction in Verrucomicrobia or Planctomycetes
ay be early indications of SOM decline?
Planctomycetes, and Verrucomicrobia were positively
y = 4.1x - 0.57
R = 0.744**
0
5
10
15
20
25
30
35
0.0 2.0 4.0 6.0 8.0
Soilorganicmatter(gkgsoil)
Verrucomicrobia (%)

17. j 2 Conclusions
onversion of CRP to cropland resulted in
ncreased SOM into lower soil depths and
ncreased bacterial diversity but this is
ypothesized to be a short-term effect
Within 1-5 yrs of conversion, bacterial
ommunities resembled long-term cropped fields
Low resiliency
onverted CRP were associated with reductions in
cologically significant taxa involved in OM

18. Thank You!