Annemarie König

Principal impacts of irrigation with polluted sewerage waters on the banks of Lower Bodocongó - PB, Brazil

A bacia do Rio Bodocongo se situa na regiao Sudoeste do Estado da Paraiba e e contribuinte da bacia do Medio Rio Paraiba, receptor da maior parte dos esgotos brutos e do efluente final da Estacao de Tratamento de Esgotos (ETE) da cidade de Campina Grande. O trecho situado a jusante da ETE, aqui chamado Baixo Bodocongo, tem 50 km de extensao e suas aguas sao usadas para irrigacao irrestrita, destacando-se forrageiras e hortalicas (alface, repolho, tomates) e para recreacao de contato primario, dentre outros. Neste trabalho analisaram-se parâmetros sanitarios, fisicos e quimicos de suas aguas, os impactos causados pelo uso na qualidade sanitaria de duas culturas irrigadas (capim e repolho) e na salinizacao dos solos. Verificou-se que essas aguas sao improprias para irrigacao irrestrita e que em nenhum dos pontos amostrados sua qualidade atende simultaneamente aos dois criterios da OMS para irrigacao: coliformes fecais < 1000 UFC 100 mL-1 e ovos de helmintos < 1 ovo L-1. Os repolhos irrigados com a agua desse rio apresentaram concentracoes de coliformes fecais de 103 NMP g-1, 17 vezes superior ao maximo para alimentos ingeridos crus. Essas aguas tem condutividade eletrica entre 2,42 a 3,51 dS m-1 e as areas irrigadas apresentam maior nivel de sais em relacao aos solos de areas nao irrigadas proximas.

Effects of the Irrigation with Treated Wastewater on Fodder Corn Production

The objective of this research was to analyze the effects of the treated wastewater and of the residual nitrogen manuring on the production of the AG 1051 hybrid fodder corn with straw, without straw and in grains. The experiment was conducted in the Sewers Treatment Station of Campina Grande city, Paraiba state, Brazil, in randomized blocks design with factorial scheme (2 x 5) + 2, having as factors two types of irrigation water (water of provisioning and treated wastewater), five doses of nitrogen (0, 60, 90, 120 and 180 kg N ha-1 and foundation manuring with P and K), and two controls (water of provisioning and treated wastewater), with four replications. The results showed that there was linear increase of the production as a function of the increase of the incorporated doses of nitrogen into the soil and although that the irrigation with treated wastewater promoted an increment of the productivity of 144% in relation to the productivity reached with the water of provisioning.

Production of Lettuce (Lactuca Sativa, L.) Under Effects of Irrigation with Treated Wastewater

The present work tells an experience of direct reuse of sewer treated at a stabilization pond in the cultivation of lettuce (Lactuca sativa, L.), evaluating the influence of irrigation on the non destructive components of growth and on the vegetable production, with the application of wastewater and of addition of organic manuring. The experiment was conducted in the dependences of the Station of Treatment of Sewer of the municipal district of Campina Grande, belonging to the Company of Water and Sewer of Paraiba state, Brazil, in entirely randomized experimental design with four replications, being the factors two types of water (provisioning and wastewater treated by system of stabilization ponds) and the presence or not of bovine fertilizer. Two cycles of lettuce cultivation were performed and the results analyzed statistically; the first experiment was accomplished during the period from July to August of 2003 and the second one from October to November of 2003. Before the harvest of the lettuce plants of the useful area of the experimental plots, the measurements of the height and of the diameter of each plant were made. Soon afterwards, all the 14 lettuce plants were harvested, making latter the wash of them to remove the soil and then to proceed the counting of the number of leaves, measurements of the length and diameter of the root and the weighting of the aerial part and of the root, separately. The productivity (kg m-2) for each treatment was evaluated in the useful area of each plot. The largest values for the productivity and for the non destructive variables were found in the lettuces produced under irrigation with wastewater and organic manuring.

Macronutrients in Soil and Lettuce After the Irrigation with Effluents of Stabilization Pond

The disposition of sewers into the soil is an old practice, dating since the centuries XVI and XVII in Germany and in England. The treated wastewater has been used in the irrigation not only for providing a continuous supplying of water, but also due to its high nutritional power, which reduces or even eliminates the need of chemical manuring. The present work tells an experience of direct reuse of sewer treated at a pond of stabilization in the cultivation of the lettuce (Lactuca sativa, L.), evaluating the chemical modifications that happen in the soil and in the vegetable with the application of wastewater and of the addition of the organic manuring. The experiment was conducted in the Campina Grande Sewage Treatment Plant, Paraiba state, Brazil, in a randomized experiment with four replications, being the factors two types of irrigation water (provision water and wastewater treated by stabilization ponds) and the presence or absence of bovine manure. Two cycles of lettuce cultivation were carried out and statistically analyzed: the first one from July to August of 2003 and the second from October to November of 2003. Macronutrients analyses were accomplished in soil and lettuce root. The addition of the organic matter through bovine fertilizer promoted larger alterations in the chemical characteristics of the soil and of the lettuce.