# Properties of Vermicomposts Derived from Cameroon Sheep Dung
## Materials and Methods
### Vermicomposting  
The experiment was conducted at the University of Rzeszow in 2016-2017 and ran for a period of six months in each year.  
Earthworms used in the experiment (_Dendrobaena veneta_ [PERSON], 1886) came from our own multi-annual breeding line. Before starting the experiment, the earthworms were selected from breeding beds and placed into containers filled with garden soil and manure for 14 days, so that they would become acclimatized to experimental conditions, in accordance with the methodology used by [PERSON] et al. [15].  
The experiment was carried out in containers: \(18\times 18\times 8\) cm. Each was filled with garden soil (2 dm\({}^{3}\)) of known physico-chemical characteristics (Kronen universal soil: pH in H\({}_{2}\)O 6.0-6.5; salinity 1.0-2.0 (mg\(\cdot\)dm\({}^{-3}\)); N 355 \(\pm\) 57 (mg\(\cdot\)dm\({}^{-3}\)); P\({}_{2}\)O\({}_{5}\) 300 \(\pm\) 36 (mg\(\cdot\)dm\({}^{-3}\)); K\({}_{2}\)O 400 \(\pm\) 59 (mg\(\cdot\)dm\({}^{-3}\)) solid, loose form, fraction 0-20 mm) and properly balanced food. Holes in the containers were made to allow for air flow. Waste biomass was contained in traps made of latthing mesh.  
Eight containers were divided between two treatments: Cameroon sheep dung (CSD) and CSD mixed in a 1:1 ratio with unpalatable (waste) hay (CSDH) as outlined below:  
* CSD (10 mature _D. veneta_ with known and balanced biomass were placed within each container--(0.550 \(\pm\) 0.016 g) + garden soil + 400 g of Cameroon sheep dung;
* CSDH (10 mature _D. veneta_ with known and balanced biomass within each container--(0.553 \(\pm\) 0.011 g) + garden soil + 400 g of Cameroon sheep dung mixed with dampened hay (in 1:1 ratio).  
To maintain appropriate waste humidity, containers were dampened every 7 days with the same volume (100 mL) of tap water (pH--7.5, conductivity--486 uS-cm\({}^{-1}\), nitrates V--8.5 mg\(\cdot\)dm\({}^{-3}\), nitrates III--0.01 mg\(\cdot\)dm\({}^{-3}\), Mg--14.2 mg\(\cdot\)dm\({}^{-3}\), hardness water--231 CaCO\({}_{3}\) mg\(\cdot\)dm\({}^{-3}\).).  
The containers were placed in an air-conditioned chamber (temperature 20 \(\pm\) 0.5 \({}^{\circ}\)C, humidity 70%). Macroelement (N, P, K, Ca, Mg) content was determined both in the waste material and in vermicompost, in accordance with the methodology used by the Ministry of Agriculture, Fisheries and Food [58]. All measurements were performed in three replications. Moreover, some trace elements (Ni, Pb, Cr, Cd, Cu) were also determined in the vermicompost.  
Organic carbon was determined by use of an elemental analyzer Vario EL Cube (Thermo Fisher Sci); N--by [PERSON]'s method, pH in H\({}_{2}\)O--by potentiometric method, salinity (NaCl g-dm-3) and conductivity (mS)--by conductometric method, phosphorus--by vanadium-molybdenum method, potassium and calcium--by flame photometry method (FES), magnesium--by atomic absorption spectrophotometry method (AAS). The C:N ratio was calculated (in mass/mass ratios).  
Cd, Cr, Cu, Pb and Ni were determined in soil extracts with aqua regia--using flame and electrothermal absorption spectrophotometry [59]. In the research pursued, the total content of trace elements was determined. The uncertainty for the total analytical procedure (including sample preparation) was below the level of 15%. The accuracy was checked using reference materials SRM 2709a (San Joaquin Soil) and the recovery (87%-102%) was acceptable for determined heavy metals.  
The dynamics of the populations of \(D\). _veneta_ during vermicomposting (CSD and CSDH) were assessed 5 times per month, using manual sorting [60]. Earthworms found were counted and had biomasses determined.  
The results were developed and presented as the mean \(\pm\) SD. Statistical analysis at a confidence level of 0.05 was performed with the use of a Student's t-test using Statistica software v.10.1.