2.3.3 Classification of Earthworms
Earthworms are broadly divided into three categories based on nature of feeding and
defecation activity and their vertical distribution in soil strata.
2.3.3.1 Epigeic
Besides having a small body size, these earthworm species have high reproduction
rate and are voracious eater of organic matter. Being surface dwellers they do not
change the soil structure, and such earthworm species are predominantly used in
vermicomposting. Examples include Eisenia fetida (brandling, red wiggler or
manure worm), Eisenia Andrei (red tiger), Lumbricus rubellus (red worms), etc.
2.3.3.2 Endogeic
The endogeic species are fairly pigmented with varied body size and feed more on
soil than organic matter, and they live in extensive horizontal burrows. These species
are rarely used in vermicomposting although they efficiently decompose dead plant
roots. Due to their burrowing nature, they take part actively in soil formation process
such as mixing and aeration. Examples include Allolobophora chlorotica (green
worms), Aporrectodea caliginosa (grey worm), etc.
2.3.3.3 Anecic
The anecic groups are burrowing earthworms forming complicated burrow system
under soil surface helping in regular mixing of soil surface matter with the lower
strata. They have large body size, relatively long-lived and have a longer growth and
reproduction time than epigeic species. Anecic species may be used in
vermicomposting but usually in combination with epigeic species. Aporrectodea
longa (black-headed worms), Lumbricus terrestris (lob worms) are examples for
anecic group.
The suitability of Eisenia fetida, Eudrilus eugeniae and Perionyx excavatus have
been described by Reinecke et al. (1992) in Table 2.2.
2.3.4 Studies on Vermifiltration
Vermifiltration as discussed earlier is a decentralized wastewater treatment option
which is recommended for adoption in small communities, colonies and rural areas
owing to the fact that the system is eco-friendly, compact and cost-effective.
2 Vermifiltration for Rural Wastewater Treatment
27
Earthworms are broadly divided into three categories based on nature of feeding and
defecation activity and their vertical distribution in soil strata.
2.3.3.1 Epigeic
Besides having a small body size, these earthworm species have high reproduction
rate and are voracious eater of organic matter. Being surface dwellers they do not
change the soil structure, and such earthworm species are predominantly used in
vermicomposting. Examples include Eisenia fetida (brandling, red wiggler or
manure worm), Eisenia Andrei (red tiger), Lumbricus rubellus (red worms), etc.
2.3.3.2 Endogeic
The endogeic species are fairly pigmented with varied body size and feed more on
soil than organic matter, and they live in extensive horizontal burrows. These species
are rarely used in vermicomposting although they efficiently decompose dead plant
roots. Due to their burrowing nature, they take part actively in soil formation process
such as mixing and aeration. Examples include Allolobophora chlorotica (green
worms), Aporrectodea caliginosa (grey worm), etc.
2.3.3.3 Anecic
The anecic groups are burrowing earthworms forming complicated burrow system
under soil surface helping in regular mixing of soil surface matter with the lower
strata. They have large body size, relatively long-lived and have a longer growth and
reproduction time than epigeic species. Anecic species may be used in
vermicomposting but usually in combination with epigeic species. Aporrectodea
longa (black-headed worms), Lumbricus terrestris (lob worms) are examples for
anecic group.
The suitability of Eisenia fetida, Eudrilus eugeniae and Perionyx excavatus have
been described by Reinecke et al. (1992) in Table 2.2.
2.3.4 Studies on Vermifiltration
Vermifiltration as discussed earlier is a decentralized wastewater treatment option
which is recommended for adoption in small communities, colonies and rural areas
owing to the fact that the system is eco-friendly, compact and cost-effective.
2 Vermifiltration for Rural Wastewater Treatment
27