Efficient land use of sludge and manure

Reports and reviews

197

Inactivation of Micro-organisms in Sewage Sludge by Stabilization Processes. Edited by D . Strauch, A . H. Havelaar and P . L'Hermite . Seminar held in Hohenheim, F.R .G ., October 1984, published 1985 . 225 pp . $37 .50 . This volume may, due to the delay in publication, seem to have been a wasted effort . However, the hazards from micro-organisms exist . Epidemiological studies have just not been able to establish statistically useful conclusions .

Efficient Land use of Sludge and Manure . Edited by A . Dam Kofoed, J. H. Williams and P . L'Hermite . Proceedings of a Round-Table Seminar, held at Brorup-Askov, Denmark, June 1985, published 1986 . 245 pp . £25 .00 and Factors Influencing Sludge Utilisation Practices in Europe . Edited by R . D . Davis, H . Haeni and P. L'Hermite . Proceedings of a Round-Table seminar held at Liebefeld, Switzerland, May 1986, published 1986 . 123 pp . £20 .00 . A major problem addressed in these two volumes is the escape of nitrogen from sludge and manure applications . Losses to the atmosphere and by denitrification represent loss of fertilizer. Escape of nitrates to groundwater also represents a potential hazard to health and a serious problem to entrophication of surface waters . The use of DCD (dicyandiamid) to reduce nitrification of NH 3 to N03 was not promising . Injected sludge carries organic matter which can aid denitrification so that there may be less chance of nitrate leaching than from equivalent applications of chemical nitrogen fertilizers . There are good summaries of each paper . Metals were discussed only at the Swiss seminar .

Long-term Effects of Sewage Sludge and Farm Slurries Applications . Edited by J. H. Williams, G . Guidi and P. L'Hermite . Proceedings of a Round-Table Seminar held in Pisa, Italy, September 1984, published 1985 . 235 pp . £25 .00 . This book reports the first EEC seminar where experts from both the sewage sludge and animal manure sides came together to discuss their common problems . Much of the emphasis was on the availability of nitrogen and phosphorous over time as a function of source and treatment including composting . There are excellent reports of the discussions at the end of each session . For example a beneficial effect of earthworm treatment of compost was reported in discussions between Hall (Rothamsted) and Tomati (Rome), although the subject was not mentioned in the formal papers .

Chemical Methods for Assessing Bio-available Metals in Sludges and Soils . Edited by R . Leschber, R . D . Davis and P . L'Hermite (1985) . 96 pp . £20 .00 . This volume deals largely with the chemical aspects of measuring availability based on the assumption that one or a small number of extractants can simulate the availability of toxic metals to plants . There is abundant evidence that different varieties of a single species have markedly different susceptibilities to the same element . In the 1960s, Bradshaw (Liverpool) identified zinc-tolerant grasses growing on mine dumps, and Hinesley (Urbana, Illinois) showed marked differences in the uptake of cadmium by