114 Abstracts

anaerobic treatment for this waste was observed, decreasing the organic content to 65580% and totally reducing the acute toxicity levels. The organic matter was still being reduced in the aerobic system, despite the fact that the effluent did not present acute toxicity anymore. During the observation period, it was concluded that the effluent did not cause any impact on the stream. This kind of treatment also seemed to be convenient for the residues of the citrus industry.

rates, determined by 14C02 evolution, were between 0.16 and 0.26%. The distribution of radioactivity in the soil profile showed that more than 90% of the total amount remained in the soil and it was mostly in the top 2cm layer of the soil. (Financial Support: CNPq, IBAMA and DLR.)

Investigations into the Aerobic Treatment of Cattle Slung With and Without the Inclusion of an Adapted Microcial Culture

Anaerobic Eflluent Piggery Waste Treatment Using a Trickling Filter C.R. Alvariiio Environmental Pollution Department, CNIC, Havana City, Cuba

P.J. Farrell and S. Beeton Department of Applied Biology, University of Central Lanca- shire, Preston, UK

An aerated batch laboratory treatment system for the removal of solubilized substrates from cattle slurry is described. Treat- ment was performed with and without the inclusion of an adapted microbial culture to slurry of 2.5 and 50% total solids continuously over an 8-day period. The system proved very successful in the elimination of soluble substrates in both treatment processes, although separation into two distinct fractions was only observed with the inclusion of the adapted microcial culture at 50% solids. Chemical analysis of the two fractions confirmed the reduction of solubilized substrates with average losses of 94.8, 83.8, 100 and 57% for suspended solids, COD, ammonia and total solids, respectively, within the liquor fraction of the slurry containing the adapted microbial culture. Reductions were found within the liquor fraction of the slurry without an inoculum, but were not of this magnitude.

Phosphorus and nitrogen must be considered two of the most important elements and the main factor responsible for eutro- phication of receiving waters. Some research has been done about nitrogen and phosphorus removal from piggery waste. In this paper, the trickling filter for anaerobic pretreated piggery waste is described. The influence of the concentration of organic matter and hydraulic loading on the depuration efficiency of the system was studied. The total volume of trickling filter was 3.6 1 and it was packed with ceramic rings. A total of five runs were done at different hydraulic load (0.3- 2.75m3/m3 day) and organic load (699-1304mg COD/l). The efficiency of depuration on ammonia-nitrogen and orthopho- sphate were 4&65% and 85-90%, respectively, for hydraulic loading range between 1.7 and 1.83 m3/m3 day.

Utilization of Rice-straw by Pycnoporus sanguineus, Tricoderma viride and Rhizopus stolonifir E. Endres and R.W.S.P. Thomas Agronomy Faculty, UFRGS, Porto Alegre, RS, Brazil

Experiences in Cornposting of Sugar Cane Agrowastes in Cuba M. Klibansky, M.A. Leon, F. Eng and M.A. Brizuela ICIDCA (Cuban Research Institute of Sugar Cane Byproducts)

The characteristics of the sugar agroindustrial sector in the Republic of Cuba, with its huge amounts of byproducts and residues concentrated around the mills and sugar cane cleaning stations, together with the known advantages of the ‘composting process’ have recently awakened interest in the application of this technology on a large scale. Results obtained in the composting of various sugar cane byproducts and residues have demonstrated the feasibility of this process in Cuban conditions without addition of any external inocula and the possibility of obtaining a biofertilizer in a l&12 week period with an adequate grade of maturity as is endorsed by the values of the C/N and HA/FA relation, humification index, cation exchange capacity as well as the bromatological analysis performed.

Pycnoporus sanguineus, Tricoderma viriak and Rhizopus stolo- nzfer were assessed for radial growth on potato dextrose agar (PDA) and on three different rice-straw agars made with either distilled water (RSA), Bushnell and Haas mineral salts solu- tion (RSB), or the mineral salts solution of Kaufmann and Kearney (RSK) at three different pH values (5, 7 and 9). Radial growth was most rapid on PDA for T. viride and R. stolonzfer, each covering the plates (9cm) in l-2 days, but P. sanguineus grew slowly on BDA, requiring more than 10 days to cover a plate. Growth rate did not appear to change as a function of pH when the fungi were growing on BDA. Of the rice-straw agars growth was most rapid on RSB at pH 5 and pH 7, with T. viride and R. stolonzfer requiring 2-3 days to cover a plate. The lactase-producing fungus, P. sanguineus, grew better on RSB than on BDA, requiring only 7 days to complete growth on the rice-straw based media. these results indicate that rice straw can serve as a carbon source for the growth of these fungi which could be used for the upgrading of rice-straw for use as animal feed.

Distribution of Atrazine in a Brazilian Red Yellow Biological Control of Disease and Spoilage of Edible Latossol Soil Produce S. Paim”, R. Scbroll’ and T. Langenbacba aInstituto de Microbiologia da UFRJ, Brazil and bGSF, Germany

P.N. Green National Collection of Industrial and Marine Bacteria (NCIMB) Ltd, Aberdeen, Scotland, UK

The herbicide atrazine is an s-triazine used worldwide in control of broadleaf weeds in agriculture, and has caused a number of environmental problems. A new microcosm test- system was used to monitor the behavior and distribution in soil profile of 14C atrazine in a Brazilian Red Latossol soil. Atrazine was applied at a rate of 3 kg is/ha. Ninety days after the application about 1% of the initially applied amount was lost by volatilization, and 0.1% by leaching. Mineralization

A significant proportion of the world’s food resource is lost each year due to disease of the plant or crop from which it is derived. In addition, further losses occur after harvest and during storage of perishable produce. Such post-harvest losses can be reduced or prevented by a variety of measures. These include improved storage and transportation meth- ods, as well as control of the disease or spoilage organisms which lead to this form of biodeterioration. In severe cases,