The drilosphere is the part of the

soil Soil, also commonly referred to as earth or dirt, is a mixture of organic matter, minerals, gases, liquids, and organisms that together support life. Some scientific definitions distinguish ''dirt'' from ''soil'' by restricting the former te ...

influenced by

earthworm An earthworm is a terrestrial invertebrate that belongs to the phylum Annelida. They exhibit a tube-within-a-tube body plan; they are externally segmented with corresponding internal segmentation; and they usually have setae on all segments. Th ...

secretions, burrowing and castings. Therefore, it is the fraction of soil which has gone through the digestive tract of earthworms, or the lining of an earthworm burrow. The average thickness of the drilosphere (lining of an earthworm burrow) is 2mm, but it can be much wider (about 8mm) around the burrows of litter-feeding earthworms. Through the drilosphere, earthworms influence soil microbial communities, with effects on microbial processes related to

soil organic matter Soil organic matter (SOM) is the organic matter component of soil, consisting of plant and animal detritus at various stages of decomposition, cells and tissues of soil microbes, and substances that soil microbes synthesize. SOM provides numerous b ...

and nutrient dynamics.Earthworm Ecology By Clive Arthur Edwards. 2nd Ed. 2004. CRC Press. A study of one soil type found that contained within the drilosphere was 40 per cent of the

aerobic Aerobic means "requiring air," in which "air" usually means oxygen. Aerobic may also refer to * Aerobic exercise, prolonged exercise of moderate intensity * Aerobics, a form of aerobic exercise * Aerobic respiration, the aerobic process of cellu ...

(and 13 per cent of

anaerobic Anaerobic means "living, active, occurring, or existing in the absence of free oxygen", as opposed to aerobic which means "living, active, or occurring only in the presence of oxygen." Anaerobic may also refer to: * Anaerobic adhesive, a bonding a ...

)

nitrogen-fixing bacteria Nitrogen fixation is a chemical process by which molecular nitrogen (), with a strong triple covalent bond, in the air is converted into ammonia () or related nitrogenous compounds, typically in soil or aquatic systems but also in industry. Atmos ...

and 16 per cent of the

denitrifier Denitrifying bacteria are a diverse group of bacteria that encompass many different phyla. This group of bacteria, together with denitrifying fungi and archaea, is capable of performing denitrification as part of the nitrogen cycle. Denitrification ...

s.T. Bhatnagar, Lombriciens et humification: Un aspect nouveau de l'incorporation microbienne d'azote induite par les vers de terre. The drilosphere is generally richer in nitrogen, phosphorus, and humified organic material than the surrounding soil. This is probably because earthworms preferentially ingest plant residue such as leaf and root litter, or occasionally fungi. The term was coined by M. B. Bouché.

References

{{reflist Soil