Fischer et al. (2014) reported that the infiltration of water in the soil directly
depends on the soil texture and earthworm abundance. They observed high water
infiltration within the soil having high sand content with large earthworm population
and vice versa. This increase in water infiltration was due to the formation of
burrows in the soil by earthworm which acts as a channel for water infiltration.
They also observed that a decrease in the earthworm abundance at the site also
disturbed the water infiltration. They also reported that this water infiltration also
changes with the ecological nature of the earthworm species.
19.4.5 Organic Carbon and Organic Matter
Organic carbon (OC) and Organic matter (OM) are the main food reserve for
earthworms (Brown et al. 2004). Earthworm populations are usually associated
with plant species in the forest or native grasslands which provide them organic
matter produced by the above-or below-ground litter (Marhan and Scheu 2005;
Campana et al. 2002; Nachtergale et al. 2002). Most species of earthworms have
the capability to discriminate between diverse kinds of forest litter. Thus, the litter
composition is the main factor that greatly affects the abundance and biomass of
earthworms. The type of vegetation, quantity and quality of their food supply also
affect the earthworm populations. Earthworms have the capability to feed on a wide
variety of organic materials and also accumulate a sufficient amount of nourishment
from organic matter from soil or microorganisms even in adverse conditions to
survive. Soil organic carbon is a critical factor in the distribution and abundance of
earthworms at a particular site (Chan and Barchia 2007). The availability of organic
matter in the soil directly influences the earthworm’s abundance and distribution.
The soil having a low content of organic matter does not support a high abundance of
earthworms (Edwards and Bohlen 1996). The types and quantity of food available
affect not only the biomass and number of earthworm populations but also their rate
of growth and fecundity (Edwards and Bohlen 1996). Various studies have been
reported a positive relationship between earthworm abundance and OC and they
showed that with an increase in OC and OM content within the soil, the abundance
and density of earthworm also increased and vice versa (Briones and Schmidt 2017).
According to Ayuke et al. (2011), the agricultural soil has a lower content of OC due
to agricultural management practices, while high OC content was observed in
undisturbed soil, which may be the reason for less earthworm diversity and abundance in agricultural fields. On the other hand, Kibet et al. (2016) and Piccoli et al.
(2016) reported that OC and OM content was much higher in the field with crop
residue left as such in the field as compared to the field without any crop residue. The
type of vegetation and its leaf litter around the earthworm species sampling site is
also an important factor. The vegetation which supports low understory biomass C:N
and C:P ratio supports high microbial activity, which in turn provides more nutrient
to earthworm species around that vegetation (De Wandeler et al. 2016). The type of
collection site, i.e. disturbed (tillage) or non-disturbed (non-tillage) are also affecting
344
S. Singh et al.
depends on the soil texture and earthworm abundance. They observed high water
infiltration within the soil having high sand content with large earthworm population
and vice versa. This increase in water infiltration was due to the formation of
burrows in the soil by earthworm which acts as a channel for water infiltration.
They also observed that a decrease in the earthworm abundance at the site also
disturbed the water infiltration. They also reported that this water infiltration also
changes with the ecological nature of the earthworm species.
19.4.5 Organic Carbon and Organic Matter
Organic carbon (OC) and Organic matter (OM) are the main food reserve for
earthworms (Brown et al. 2004). Earthworm populations are usually associated
with plant species in the forest or native grasslands which provide them organic
matter produced by the above-or below-ground litter (Marhan and Scheu 2005;
Campana et al. 2002; Nachtergale et al. 2002). Most species of earthworms have
the capability to discriminate between diverse kinds of forest litter. Thus, the litter
composition is the main factor that greatly affects the abundance and biomass of
earthworms. The type of vegetation, quantity and quality of their food supply also
affect the earthworm populations. Earthworms have the capability to feed on a wide
variety of organic materials and also accumulate a sufficient amount of nourishment
from organic matter from soil or microorganisms even in adverse conditions to
survive. Soil organic carbon is a critical factor in the distribution and abundance of
earthworms at a particular site (Chan and Barchia 2007). The availability of organic
matter in the soil directly influences the earthworm’s abundance and distribution.
The soil having a low content of organic matter does not support a high abundance of
earthworms (Edwards and Bohlen 1996). The types and quantity of food available
affect not only the biomass and number of earthworm populations but also their rate
of growth and fecundity (Edwards and Bohlen 1996). Various studies have been
reported a positive relationship between earthworm abundance and OC and they
showed that with an increase in OC and OM content within the soil, the abundance
and density of earthworm also increased and vice versa (Briones and Schmidt 2017).
According to Ayuke et al. (2011), the agricultural soil has a lower content of OC due
to agricultural management practices, while high OC content was observed in
undisturbed soil, which may be the reason for less earthworm diversity and abundance in agricultural fields. On the other hand, Kibet et al. (2016) and Piccoli et al.
(2016) reported that OC and OM content was much higher in the field with crop
residue left as such in the field as compared to the field without any crop residue. The
type of vegetation and its leaf litter around the earthworm species sampling site is
also an important factor. The vegetation which supports low understory biomass C:N
and C:P ratio supports high microbial activity, which in turn provides more nutrient
to earthworm species around that vegetation (De Wandeler et al. 2016). The type of
collection site, i.e. disturbed (tillage) or non-disturbed (non-tillage) are also affecting
344
S. Singh et al.