4.5 Review

Methods for evaluating human impact on soil microorganisms based on their activity, biomass, and diversity in agricultural soils

Journal

JOURNAL OF PLANT NUTRITION AND SOIL SCIENCE
Volume 169, Issue 3, Pages 295-309

Publisher

WILEY-V C H VERLAG GMBH
DOI: 10.1002/jpln.200521941

Keywords

activity; biomass; diversity; conversion factors; PLFA; DNA; turnover

Ask authors/readers for more resources

The present review is focused on microbiological methods used in agricultural soils accustomed to human disturbance. Recent developments in soil biology are analyzed with the aim of highlighting gaps in knowledge, unsolved research questions, and controversial results. Activity rates (basal respiration, N mineralization) and biomass are used as overall indices for assessing microbial functions in soil and can be supplemented by biomass ratios (C : N, C : P, and C : S) and eco-physiological ratios (soil organic C : microbial-biomass C, qCO(2), qN(min)). The community structure can be characterized by functional groups of the soil microbial biomass such as fungi and bacteria, Gram-negative and Gram-positive bacteria, or by biotic diversity. Methodological aspects of soil microbial indices are assessed, such as sampling, pretreatment of samples, and conversion factors of data into biomass values. Microbial-biomass C (mu g (g soil)(-1)) can be estimated by multiplying total PLFA (nmol (g soil)(-1)) by the F-PLFA-factor of 5.8 and DNA (mu g (g soil)(-1)) by the FDNA-factor of 6.0. In addition, the turnover of the soil microbial biomass is appreciated as a key process for maintaining nutrient cycles in soil. Examples are briefly presented that show the direction of human impact on soil microorganisms by the methods evaluated. These examples are taken from research on organic farming, reduced tillage, de-intensification of land-use management, degradation of peatland, slurry application, salinization, heavy-metal contamination, lignite deposition, pesticide application, antibiotics, TNT, and genetically modified plants.

Authors

I am an author on this paper
Click your name to claim this paper and add it to your profile.

Reviews

Primary Rating

4.5
Not enough ratings

Secondary Ratings

Novelty
-
Significance
-
Scientific rigor
-
Rate this paper

Recommended

No Data Available
No Data Available