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Updated: Jul 4, 2026
10:30
Soil Lysimeter Excavation for Coupled Hydrological, Geochemical, and Microbiological Investigations
Published on: September 11, 2016
Spatial and temporal variations of microbial properties at different scales in shallow subsurface sediments
C Zhang1, R M Lehman, S M Pfiffner
1Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA.
Applied Biochemistry and Biotechnology
|April 1, 1997
Summary
Water and nutrient availability, along with land use, significantly impact microbial abundance and activity in subsurface environments. These factors influence microbial properties at both centimeter and meter scales.
Area of Science:
- Environmental microbiology
- Subsurface ecology
- Soil science
Background:
- Microbial communities drive essential subsurface processes.
- Understanding microbial responses to environmental factors is crucial for soil health and ecosystem function.
- Spatial and temporal variations in microbial properties require investigation at multiple scales.
Purpose of the Study:
- To investigate microbial abundance, activity, and community-level physiological profiles (CLPP) at centimeter and meter scales.
- To determine the influence of water availability, nutrient status, and land use on subsurface microbial communities.
- To analyze spatial and temporal variations in microbial properties using regression models.
Main Methods:
- Quantification of aerobic culturable heterotrophs (ACH) and microaerophiles.
- Measurement of glucose mineralization rates (GMR) under aerobic and anaerobic conditions.
- Assessment of community-level physiological profiles (CLPP) to evaluate carbon source utilization.
- Application of regression models to analyze spatial and temporal data.
Main Results:
- Microbial abundance and activity peaked in the water table zone at the centimeter scale, highlighting water availability's importance.
- Microbial populations decreased with depth, while anaerobic GMR increased, suggesting low redox potentials.
- Microbial communities in soybean fields showed greater carbon source utilization than those in corn fields, linked to nutrient differences.
- Significant spatial and temporal variations were observed for ACH, microaerophiles, anaerobic GMR, and CLPP.
Conclusions:
- Water availability is a key driver of microbial abundance and activity at the centimeter scale in subsurface environments.
- Nutrient availability and land use (e.g., crop type) significantly influence microbial community structure and function.
- Subsurface microbial properties exhibit substantial spatial and temporal variability influenced by environmental factors.
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