Advances in the growth of hitherto unculturable soil bacteria have emphasized the requirement for rapid bacterial identification methods. Due to the slow-growing strategy of microcolony-forming soil bacteria, successful fluorescence in situ hybridization (FISH) requires an rRNA enrichment step for visualization. In this study, catalyzed reporter deposition (CARD)-FISH was employed as an alterna...

Rising global temperatures may increase the rates of soil organic matter decomposition by heterotrophic microorganisms, potentially accelerating climate change further by releasing additional carbon dioxide (CO2) to the atmosphere. However, the possibility that microbial community responses to prolonged warming may modify the temperature sensitivity of soil respiration creates large uncertainty...

It is commonly assumed that microbial communities are structured by "bottom-up" ecological forces, although few experimental manipulations have rigorously tested the mechanisms by which resources structure soil communities. We investigated how plant substrate availability might structure fungal communities and belowground processes along an experimental plant richness gradient in a grassland ec...

The substrate-induced respiration inhibition (SIRIN) method of Anderson and Domsch for partitioning bacteria1 and fungal contributions to soil respiration was modified for application to dry soils. This new method also provided a comparative basis when measuring SIRIN in soils of different moisture contents. Soil was incubated under optimum moisture conditions (55% water-filled pore space) to m...

The primary habitat for Bacillus sp. is the soil. In this environment, they remain inactive until a suitable substrate (food source) becomes available. Usually these substrates include large molecules from the remains of plants and animals. The large molecules, like proteins, lipids, and carbohydrates are suitable substrate for Bacillus sp. because these strains excrete enzymes which break thes...

Soil enzyme activities are the direct expression of the soil community to metabolic requirements and available nutrients. While the diversity of soil organisms is important, the capacity of soil microbial communities to maintain functional diversity of those critical soil processes through disturbance, stress or succession could ultimately be more important to ecosystem productivity and stabili...

Phospholipid fatty acid (PLFA) analysis of a soil microbial community was coupled with (13)C isotope tracer analysis to measure the community's response to addition of 35 microg of [(13)C]toluene ml of soil solution(-1). After 119 h of incubation with toluene, 96% of the incorporated (13)C was detected in only 16 of the total 59 PLFAs (27%) extracted from the soil. Of the total (13)C-enriched P...

The indirect responses of soil microbiota to changes in plant physiology effected by elevated atmospheric carbon dioxide have the potential to alter nutrient availability and soil carbon storage. We measured fine root density, microbial biomass nitrogen, rates of nitrogen mineralization and nitrification, substrate utilization by soil bacteria and extracellular enzyme activities (EEA) associate...

Understanding of soil processes is essential for addressing the global issues of food security, disease transmission and climate change. However, techniques for observing soil biology are lacking. We present a heterogeneous, porous, transparent substrate for in situ 3D imaging of living plants and root-associated microorganisms using particles of the transparent polymer, Nafion, and a solution ...

Soil organic carbon is chemically heterogeneous, and microbial decomposers face a physiological challenge in metabolizing the diverse array of compounds present in soil. Different classes of polymeric compounds may require specialized enzymatic pathways for degradation, each of which requires an investment of microbial resources. Here we tested the resource allocation hypothesis, which posits t...