Global soil microbial biomass decreases with aridity and land‐use intensification

<p>Soil microbiota ensuring sustainable functioning of terrestrial ecosystems is strongly dependent on climatic conditions and vegetation type. Even within the same climatic zone, active land use alters the size, structure and functioning of the microbial community. We hypothesized that land use effect on soil microbial biomass will be more pronounced under impact of global warming. We also tested whether the biomass of specific microbial group (e.g., fungi) is more sensitive to environmental changes than total microbial biomass.</p><p>We proved these hypotheses in the experiments based on Global Change Experimental Facility platform, located at the field research station of the Helmholtz-Centre for Environmental Research in Bad Lauchst&#228;dt near Halle, Saxon-Anhalt, Germany. Experimental setup included 50 plots, located in 10 blocks (5 plots per block). Five blocks are under ambient climate and the rest 5 blocks are subjected to a realistic climate change treatment (under conditions predicted by several models of climate change in Central Germany for 2050&#8211;2080 period). Five land use types were established in every block: conventional farming; organic farming; intensively used meadow, extensively used meadow and extensively used pasture. We determined soil microbial biomass and its fungal component by chloroform fumigation-extraction method and by ergosterol content, respectively. We found that fungal biomass was more sensitive to intensive land use for crop production than to climate change. The possible mechanisms of such a sensitivity will be discussed.</p>

Download Full-text

Activity of soil microbial biomass altered by land use in the southwestern Amazon

Bragantia ◽

10.1590/1678-4499.066 ◽

2016 ◽

Vol 75 (1) ◽

pp. 79-86 ◽

Cited By ~ 4

Author(s):

André Mancebo Mazzetto ◽

Carlos Eduardo Pellegrino Cerri ◽

Brigitte Josefine Feigl ◽

Carlos Clemente Cerri

Keyword(s):

Land Use ◽

Microbial Biomass ◽

Soil Microbial Biomass ◽

Canonical Variate ◽

Physical Factors ◽

Mato Grosso ◽

Soil Microbial ◽

Physiological Diversity ◽

Increasing Demand ◽

Agricultural Areas

ABSTRACT The increasing demand for food creates environmental problems, mainly due to the removal of native vegetation cover for agriculture expansion in Brazil. These changes in land use lead to changes in the soil organic matter dynamics. Microorganisms represent the most biological and physiological diversity in soil, as well as are responsible for more than 95% of the decomposition and nutrient cycling processes. The objective in this research was to check if there is difference of patterns in activity of soil microbial biomass under varied natural vegetation, pastures in use and agricultural systems recently established. The area covered by this study corresponds to the states of Rondônia and Mato Grosso. Canonical variate analysis was used in physical, chemical and microbiological factors in each ecoregion and land use, looking for patterns and variables that can differentiate them. The native areas showed distinct patterns in the dynamics of microbiological attributes mainly related to the amount of litter in each biome studied. For the disturbed areas, there were similar results between pastures and native areas, significantly different from the results obtained in agricultural areas, which, due to differences in management and kind of cultures analyzed, showed a great variability in the final result. The results support the recommendation for use of microbiological attributes as indicators of land use change, combined with chemical and physical factors of the soil.

Download Full-text

Soil microbial biomass phosphorus under different land use systems of Central Himalaya

Tropical Ecology ◽

10.1007/s42965-021-00184-z ◽

2021 ◽

Author(s):

Kirtika Padalia ◽

Surendra Singh Bargali ◽

Kiran Bargali ◽

Vijyeta Manral

Keyword(s):

Land Use ◽

Microbial Biomass ◽

Soil Microbial Biomass ◽

Central Himalaya ◽

Land Use Systems ◽

Soil Microbial

Download Full-text

Relationships between bacterial diversity, microbial biomass, and litter quality in soils under different plant covers in northern Rio de Janeiro State, Brazil

Canadian Journal of Microbiology ◽

10.1139/w09-066 ◽

2009 ◽

Vol 55 (9) ◽

pp. 1089-1095 ◽

Cited By ~ 27

Author(s):

S. M. Ndaw ◽

A. C. Gama-Rodrigues ◽

E. F. Gama-Rodrigues ◽

K. R.N. Sales ◽

A. S. Rosado

Keyword(s):

Land Use ◽

Microbial Biomass ◽

Bacterial Diversity ◽

Litter Quality ◽

Soil Microbial Biomass ◽

Stand Age ◽

N Availability ◽

Eucalyptus Plantation ◽

Soil Microbial ◽

C And N

Microbial populations are primarily responsible for the decomposition of organic residues, the nutrients cycle, and the flow of energy inside of soil. The present study was undertaken to link soil microbiological and soil biochemical parameters with soil- and litter-quality conditions in the surface layer from 5 sites differing in plant cover, in stand age, and in land-use history. The aim was to see how strongly these differences affect the soil microbial attributes and to identify how microbiological processes and structures can be influenced by soil and litter quality. Soil and litter samples were collected from 5 sites according to different land use: preserved forest, nonpreserved forest, secondary forest, pasture, and eucalyptus plantation. Soil and litter microbial biomass and activity were analysed and DNA was extracted from soil. The DNA concentrations and soil microbial C and N correlated positively and significantly, suggesting that these are decisive nutrients for microbial growth and time required for microbial biomass renewal. The litter microbial biomass represented a source of C and N higher than soil microbial biomass and can be an important layer to contribute to tropical soil with low C and N availability. The litter quality influenced the litter and soil microbial biomass and activity and the soil bacterial diversity. The chemical and nutritional quality of the litter influenced the structure and microbial community composition in the eucalyptus plantation.

Download Full-text