Name: FRANCIELEN BARROSO ARAGÃO
Type: PhD thesis
Publication date: 01/12/2021
Advisor:
Name |
Role |
|---|---|
| Silvia Tamie Matsumoto | Advisor * |
Examining board:
| Name |
Role |
|---|---|
| Antelmo Ralph Falqueto | Internal Alternate * |
| Diolina Moura Silva | Internal Examiner * |
| Elias Terra Werner | Internal Examiner * |
| IAN DRUMOND DUARTE | External Examiner * |
| Larissa Fonseca Andrade Vieira | External Examiner * |
| LÍVIA DORSCH ROCHA | External Alternate * |
| Silvia Tamie Matsumoto | Advisor * |
Summary: The inadequate management of residues from swine production can cause
contamination of water courses, soil and air, representing a risk to the
environment. The objective of this work was to evaluate the environmental risk
of the raw residue and effluent from the stabilization pond of swine biodigester,
to evaluate the reuse of the effluent from the stabilization pond as a biofertilizer
and the quality of water samples from the Santa Maria do Doce River, in the
around the pig farm. The effluents from the swine biodigester (raw waste and
from the stabilization pond) and river water samples were collected in the
municipality of Santa Tereza-ES, Brazil, and chemical characterization analyzes
were carried out. Dilutions were carried out from the pure effluents (C1), and
successive reductions were made in the amount of effluent, 50% (C2), 25%
(C3), 12.5% ​​(C4), 6.25% (C5) , 3.12% (C6), 0.78% (C7) and 0.39% (C8). The
river samples were collected in two campaigns (highest and lowest rainfall), in 3
sampling stations: upstream from the swine farm (EA1), close to the swine farm
(EA2) and downstream from the swine farm (EA3). Seeds of Lactuca sativa and
Allium cepa were germinated in the treatments, and germination, root growth,
evaluation of toxicogenetic potential and analyzes of the activity of SOD, CAT,
GST enzymes and quantification of GSH and LPO were evaluated. Dilutions
from the stabilization pond were used to evaluate the effluent as a biofertilizer in
corn plants, through gas exchange and growth analyses. Two controls were
used: a treatment containing only water and a treatment with commercial
fertilizer. All data were submitted to ANOVA, followed by the Kruskal Wallis or
Tukey mean test (p<0.05). The two effluents inhibited the germination of L.
sativa and A. cepa, in addition to reducing root growth, and promoting higher
frequencies of chromosomal alterations in the other concentrations. The
observed damages are possibly related to the heavy metals found in the studied
samples. The river samples showed a reduction in the mitotic index in EA2 and
EA3 (second campaign) in A. cepa compared to the negative control, in both
models, there was an increase in chromosomal alterations (EA2 and EA3). The
damages observed are possibly related to the excess of aluminum found in the
samples, human activity in the surroundings of the river, the discharge of
effluents from pig farming and domestic sewage. Corn plants, when compared
to the water control, showed a significant increase in biomass, but the higher
concentrations of the effluent prevented seed germination. Possibly the excess
of K and Na may have caused water stress in the seeds, preventing
germination and development of plants, in which the dilution of the effluent
reduced the effects of excess K and Na and, consequently, reduced the
availability of other essential nutrients for the corn plants.
Key-Words: Stabilization pond; Allium cepa; Lactuca sativa; Zea Mays; cell
cycle.
