Prospecção ambiental em áreas rurais: o estudo de caso da zootecnia em Paulista - PE

Abstract

Agricultural activities are causing environmental impacts and all of those activities generate liquid effluents, which when improperly disposed can cause soil, air and water pollution. In addition, the use of natural resources in a irresponsibly way also causes negative results to the environment. The objective of this study was to determine through one case study, the main environmental impacts and their variables due the zootechnical activities developed in the stretch area located on the banks of the Paratibe River, municipality of Paulista (Pernambuco state) during the months of June, July and August of 2018, using the following methodologies: field check list to characterize the environmental diagnosis; hydrological analysis of the Paratibe river in the aforementioned station for pH measurement, transparency, nutrient concentration; and samples for plankton community analysis to perform the occurrence stimation of each organism identified that is in this work function as bioindicators. Data from the planktonic community were submitted to statistical analysis using the Relative Abundance (RA) and Frequency of occurrence (OF) methods. The impacts evidenced in the area during the months of June, July and August/2018 were quantified respectively with the following total indices: -173, -178, -232 which prove the presence of extreme environmental impacts. The nutrient contents were 2.8 mg/L for nitrite concentration and 39.95 mg/L nitrate, mean concentrations of ammonia in the Paratibe river were 3.995 mg/L and for water transparency measurements were verified values of 30 and 40 cm depth of penetration of sunlight. In the three collected samples of plankton 5 taxa were identified in total (Protozoa, Rotifera, Nematoda, Polychaeta, and Copepoda) plus Diptera larvae (insects). With respect to the Protozoa in this work they were visualized as external parasites of some Copepoda organisms, as well as filamentous bacteria. It was verified that the contents of all the analyzed nutrients exceed the maximum concentrations allowed by Resolution 357 ̸2005 of the National Council of the Environment (Brazilian CONAMA); also, that there is a little variety and less survival rates of plankton in the waters of the Paratibe river and that there is much contamination of solid waste in the studied environmental area. Therefore, the region needs preventive and emergencial measures that will guarantee the conservation of this ecosystem and will help in the development of a sustainable animal production breeding system, capable of providing sanitary security to the producer and the population.