Soil Fauna Activities in Agricultural Greek Landscapes
95
several long-term entomological agronomic research programs, some operate since
>170 years, it has been found that due to agricultural intensification the relative
earthworm biomass declined by 50–100% (mean 83.3%) in comparison to organic
fertilizing [15]. Further a soil moisture reduction by –22.3%, topsoil erosion, a mean
loss of SOC/SOM humus by –56.8%, and a 2–9 times earthworm abundance and
composition diversity reduction from the optima were recorded. In this context it
is observed that recruitment from surrounding fields apparently doesnot balance
earthworm declines ([106], [15]). Kopiejewska et al. [25] counted 279–349 individuals (biomass of 103.3–119.5 g) per square meter of a mineral fertilized pasture in
comparison to 351–418 earthworm individuals (biomass of 142.4–173.0 g) in an
organic fertilized pasture (P < 0.05). In both studied pasture treatments the earthworm species L. terrestris and A. rosea were present, but Apporectodea caliginosa
dominated the total number by 77.0–93.2% in the mineral fertilized pasture [25].
Across seven of the major biomes on Earth [107] compared in a meta-analysis of
>1300 data points the belowground plant, microbial, and faunal biomass. In this
study it was found that the microbial biomass carbon represented 0.6–1.1% of soil
organic carbon (r
2
= 0.91), the belowground plant biomass 1–20% of total carbon (r
2
= 0.42), and the belowground soil faunal biomass accounted for <4% of the microbial biomass, for approximately 50% of the total animal biomass across all biomes.
In spite of the available >1300 data points our understanding of the global belowground biomass and community structure patterns is limited, although it has been
observed that the detritivores and geophagous earthworm “ecosystem engineers”, as
part of the wide soil microbial/fauna biomass ratio, are majorly active in the upper
15–35 cm soil layer [108, 109]. The databases in the “Acta zoologica Hungaria,
28, 421–454” are currently over 6000 plant litter and mammalian dung consuming,
plant material into deeper soil layers transporting, to nutrient turnover contributing,
seedling development and plant favouring growth earthworm species, inclusively the
megadrile earthworm families suborders (Lumbricina and Moniligastrida), listed and
named [110–114]. Identification of juvenile earthworms by morphological comparison is not easy and thus the use of majorly under development DNA based methods is
recommended to underestimate not the from soil type to soil type in numbers varying
epigeic endogeic and anecic earthworms, particularly in N, P fertilized, limed, and
tilled soils (Fig. 4; [115, 116]). Earthworms prefer well- aerated soils in areas with
around 800 mm rainfall per year, a good availability of low-humified organic material, a soil pH between 5 and 7, and in such environments the earthworm abundance
may range from 30 to 300 individuals (m-3) and the biomass from 110–1100 kg/ha
(Table 1; [110]). The maturing periods of growing earthworms is 1–2 years and
the lifespan 1.5–4 years while not favourable conditions are related to acidic soils
with high clay contents, generally found in waterlogged peats (pH < 4), as well
as coarse, freely drained and often too dry soils are not favourable for earthworms
[117]. Earthworm species differ in length between 1–1.5 m (weight about 600 g).
For example, small, 10–20 mm in size, are forest litter dwelling earthworms, having
short lifespans because of the living conditions, whereas for South African earthworm a length of 7 m long (30 kg weight) was reported [118]. In Europe, spread
epigeic, endogeic and anecic earthworms (Figs. 3 and 4) are decimated by predating,
95
several long-term entomological agronomic research programs, some operate since
>170 years, it has been found that due to agricultural intensification the relative
earthworm biomass declined by 50–100% (mean 83.3%) in comparison to organic
fertilizing [15]. Further a soil moisture reduction by –22.3%, topsoil erosion, a mean
loss of SOC/SOM humus by –56.8%, and a 2–9 times earthworm abundance and
composition diversity reduction from the optima were recorded. In this context it
is observed that recruitment from surrounding fields apparently doesnot balance
earthworm declines ([106], [15]). Kopiejewska et al. [25] counted 279–349 individuals (biomass of 103.3–119.5 g) per square meter of a mineral fertilized pasture in
comparison to 351–418 earthworm individuals (biomass of 142.4–173.0 g) in an
organic fertilized pasture (P < 0.05). In both studied pasture treatments the earthworm species L. terrestris and A. rosea were present, but Apporectodea caliginosa
dominated the total number by 77.0–93.2% in the mineral fertilized pasture [25].
Across seven of the major biomes on Earth [107] compared in a meta-analysis of
>1300 data points the belowground plant, microbial, and faunal biomass. In this
study it was found that the microbial biomass carbon represented 0.6–1.1% of soil
organic carbon (r
2
= 0.91), the belowground plant biomass 1–20% of total carbon (r
2
= 0.42), and the belowground soil faunal biomass accounted for <4% of the microbial biomass, for approximately 50% of the total animal biomass across all biomes.
In spite of the available >1300 data points our understanding of the global belowground biomass and community structure patterns is limited, although it has been
observed that the detritivores and geophagous earthworm “ecosystem engineers”, as
part of the wide soil microbial/fauna biomass ratio, are majorly active in the upper
15–35 cm soil layer [108, 109]. The databases in the “Acta zoologica Hungaria,
28, 421–454” are currently over 6000 plant litter and mammalian dung consuming,
plant material into deeper soil layers transporting, to nutrient turnover contributing,
seedling development and plant favouring growth earthworm species, inclusively the
megadrile earthworm families suborders (Lumbricina and Moniligastrida), listed and
named [110–114]. Identification of juvenile earthworms by morphological comparison is not easy and thus the use of majorly under development DNA based methods is
recommended to underestimate not the from soil type to soil type in numbers varying
epigeic endogeic and anecic earthworms, particularly in N, P fertilized, limed, and
tilled soils (Fig. 4; [115, 116]). Earthworms prefer well- aerated soils in areas with
around 800 mm rainfall per year, a good availability of low-humified organic material, a soil pH between 5 and 7, and in such environments the earthworm abundance
may range from 30 to 300 individuals (m-3) and the biomass from 110–1100 kg/ha
(Table 1; [110]). The maturing periods of growing earthworms is 1–2 years and
the lifespan 1.5–4 years while not favourable conditions are related to acidic soils
with high clay contents, generally found in waterlogged peats (pH < 4), as well
as coarse, freely drained and often too dry soils are not favourable for earthworms
[117]. Earthworm species differ in length between 1–1.5 m (weight about 600 g).
For example, small, 10–20 mm in size, are forest litter dwelling earthworms, having
short lifespans because of the living conditions, whereas for South African earthworm a length of 7 m long (30 kg weight) was reported [118]. In Europe, spread
epigeic, endogeic and anecic earthworms (Figs. 3 and 4) are decimated by predating,