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Revise existing guidelines on safe use of sewage sludge for clover & other legumes by determining effects of heavy metal (follow on SP0117) - SP0101

(New code SP0117)

SP0101. Sewage sludge contaminants.

Current guidelines for sewage disposal on arable land may have adverse effects on some crops and the environment. It is thought that elevated soil heavy metal levels can impair growth of clover and some legumes that have symbiotic association with N fixing microorganisms. This study will build on existing research on clover and will initiate new research on peas/beans to examine the effects of heavy metals from sewage sludges on legume/microbial interactions and crop growth and yield. At established and new experimental plots representing a range of soil types, sewage sludge will be applied to clover and legume crops in the late summer. Heavy metals will then be analysed in soils during the autumn period and in harvested legume crops the following summer; with clover, 3 harvest cuts will be taken each season (May, July and August) for analysis of heavy metals. Yields of all crops on treated plots will also be recorded. Results will be used to revize existing guidelines on the safe use of sewage sludges for clover and other legume crops by determining the impact of heavy metals on crop growth and yield.
To determine the impact of sewage sludge on the yield of white clover and other legumes (peas/beans). To determine the impact of sewage sludge on the yield of legumes. To provide a test bed facility for IACR (RES) to determine the effect of heavy metals on soil and plant microbial spp. (especially Rhizobium spp.)
Project Documents
• Final Report : Effect of heavy metals from sewage sludge on the growth and yield of legumes   (227k)
Time-Scale and Cost
From: 1991

To: 1995

Cost: £388,000
Contractor / Funded Organisations
Environmental Protection              
Fields of Study
Soil Protection