Development of microbial communities in organochlorine pesticide contaminated soil: A post-reclam...

1. Materials and methods

1.1. Fifteen soil samples were collected from a field for crops, with characteristics of a sandy Cambisol

1.2. Se realizo el respectivo tamizaje a dicha muestra a través de una malla de 4 mm, hata su secado al aire. La muestra se rego con agua esteril y se incubó a temperatura ambiente durante 14 días

1.3. At the end of time it was evident that the soil was enriched with lindane (alkyl halide), dissolving in the acetone and water solution

1.4. To carry out the evaluation of the microbial communities in the soil of the rhizosphere contaminated with lindane, barley seeds were used, which were sterilized with ethanol and sodium hypochlorite transferred to nutrient broth medium agar plates and incubated in the dark for 72 hours at 28 ° C, to synchronize germination

2. Soil quality parameters

2.1. To determine the carbon of microbial biomass after fumigation with chloroform, the samples were extracted from which they were carried out in triplicate and stored at -20 ° C for their subsequent measurement. Organic Carbon and Nitrogen were measured in an analyzer of total carbon

2.1.1. Project specifications

2.1.2. End User requirements

2.1.3. Action points sign-off

3. Sampling procedure

3.1. To collect the samples, each pot was emptied and the soil sample was crushed to obtain the roots, which were stored in plastic bags. The mass of the soil was harvested for the determination of the microbial carbon biomass, the dissolved organic carbon, nitrogen, and pH this sample was stored at 4 ° C

4. Results

4.1. Plant development and physical-chemical properties of the soil

4.2. Lindane severely affected the development of barley plants

4.3. The pH values ​​in bulk soil decreased significantly over time.In the rhizosphere soil, the DOC concentration was significantly higher

4.3.1. Microbial biomass carbon and bacterial abundance

4.3.1.1. In the bulk soil sample, the microbial biomass was significantly higher at 14 days, compared to the 28 day time pointIn bulk soil, lindane concentration had a significant influence on overall bacterial abundance

5. Conclusion

5.1. The results obtained in the laboratory show that the functional parameters of the soil that were investigated, as well as the microbial communities, are strongly affected by the traces of lindane.

5.1.1. Materials

5.1.2. Personnel

5.1.3. Services

5.1.4. Duration

5.2. Lindane had severe effects on soil functionality preventing plant development and nitrogen fixation of diazotrophs defects that could hinder soil restoration efforts when non-resistant crops are involved

5.3. Changes in the composition of the bacterial community of the rhizosphere generally related to the toxic effects of lindane on plants