Contaminated sludge cake experiment

Local identifier
W/CS/427
Years operational
1994—
Objective
To test the effect of zinc, copper and cadmium enriched sewage sludges on soil microbial activity and agricultural productivity.
Description
Enables the comparison of different sewage sludge processing (digested versus undigested), metal concentrations (zinc, copper and cadmium) at four rates up to EU limits and period of application (short term versus long-term). All had the same amount of organic matter added. Samples of the sludge used and periodic soil and plant samples are available in the Rothamsted Sample Archive. This experiment is part of a network of 9 sites across the UK and can also be compared with related Metal Amended Liquid Sludge Experiment and Metal Salts Experiment, also at Woburn.
Farm operation data?
Sample archive?
Samples available?
 
Data Access Statement
Available to any researcher on request
Data license
CC BY
Data policy
Yes (not online)
Organizations
Rothamsted Research
research organisation
Woburn Experimental Farm
experimental research station
Person
Prof. Steve McGrath
principal investigator
Rothamsted Research
Sustainable Agricultural Sciences

Site: Butt Close West

Type
research station field
Location
Husborne Crawley
Bedfordshire
United Kingdom
Geographic location
52.01195, -0.597963
© OpenStreetMap contributors
Elevation
96 Metres
Visits permitted?
No
Management
Mineral fertilisers added every year. Plots were bounded by permanent grass strips to prevent soil movement during cultivation. Cultivations were carried out annually to ensure that the sludge additions were evenly incorporated in the top 0-25cm and to encourage organic matter breakdown of the sludge cakes. The soil pH was maintained at 6.5.
Soil type
arenosol
Soil properties
VariableDepthValue (range)UnitsRef yearEstimated?Baseline?
sand content0 – 25 Centimetres80 Percent1994
silt content0 – 25 Centimetres12 Percent1994
clay content0 – 25 Centimetres8 Percent1994
soil pH0 – 25 Centimetres7.2 1994
soil organic carbon0 – 25 Centimetres1.3 Percent1994
Climatic type
temperate oceanic climate

Design period: (1994—)

Design Type
Randomized complete block design
Description
Plots measured 6 x 8m
Design description
Five types of sewage sludge cake were applied: 1. Digested low metal sludge 2. Digested sludges with 1 of 4 rates of zinc contamination 3. Undigested sludges with 1 of 4 rates of copper contamination 4. Digested sludges with 1 of 4 rates of cadmium contamination 5. Undigested low metal sludge Sludges were applied in two different ways, as short-term treatments applied in four large applications between 1994 and 1997 or as long-term treatments of annual applications between 1994 and 2014 of approximately 1/25th of the amounts of the same sludges to realize the same total dose of metal application as in the short term treatments in 25 years.
Number of blocks
3
Number of plots
63
Number of harvests per year
1
Crop
CropYears grown
wheat
Factors
zinc nutrient exposure
Applied with digested sludge
Plot application: Whole plot
Rate 1  (254 kg/ha)
1994—1997
Application frequency: annually
Rate 2  (514 kg/ha)
1994—1997
Application frequency: annually
Rate 3  (784 kg/ha)
1994—1997
Application frequency: annually
Rate 4  (1065 kg/ha)
1994—1997
Application frequency: annually
low rate  (15 kg/ha)
1994—2014
Application frequency: annually
copper nutrient exposure
Applied with undigested sludge
Plot application: Whole plot
Rate 1  (125 kg/ha)
1994—1997
Application frequency: annually
Rate 2  (245 kg/ha)
1994—1997
Application frequency: annually
Rate 3  (375 kg/ha)
1994—1997
Application frequency: annually
Rate 4  (500 kg/ha)
1994—1997
Application frequency: annually
low rate  (7.5 kg/ha)
1994—2014
Application frequency: annually
cadmium exposure
applied with digested sludge
Plot application: Whole plot
Rate 1  (2.15 kg/ha)
1994—1997
Application frequency: annually
Rate 2  (4.64 kg/ha)
1994—1997
Application frequency: annually
Rate 3  (7.22 kg/ha)
1994—1997
Application frequency: annually
Rate 4  (9.72 kg/ha)
1994—1997
Application frequency: annually
low rate  (0.15 kg/ha)
1994—2014
Application frequency: annually

Related publications

  • Gibbs, P. A. , Chambers, B. J. , Chaudri, A. M. , McGrath, S. P. , Carlton-Smith, C. H. , Bacon, J. R. , Campbell, C. D. and Aitken, M. N. (2006) "Initial results from a long-term, multi-site field study of the effects on soil fertility and microbial activity of sludge cakes containing heavy metals", Soil Use and Management, 22, 11-21
  • Charlton, A. , Sakrabani, R. , McGrath, S. P. and Campbell, C. D. (2016) "Long-term Impact of Sewage Sludge Application on Rhizobium leguminosarum biovar trifolii: An Evaluation Using Meta-Analysis", Journal of Environmental Quality, 45, 1572-1587
  • McGrath, S. P. , Chambers, B. J. , Taylor, M. J. and Carlton-Smith, C. H. (2012) "Biofortification of zinc in wheat grain by the application of sewage sludge", Plant and Soil, 361, 97-108
  • Macdonald, C. A. , Clark, I. M. , Zhao, F.-J. , Hirsch, P. R. , Singh, B. K. and McGrath, S. P. (2011) "Long-term impacts of zinc and copper enriched sewage sludge additions on bacterial, archaeal and fungal communities in arable and grassland soils", Soil Biology & Biochemistry, 43, 932-941
  • Chaudri, A. , McGrath, S. , Gibbs, P. , Chambers, B. , Carlton-Smith, C. , Bacon, J. , Campbell, C. and Aitken, M. (2008) "Population size of indigenous Rhizobium leguminosarum biovar trifolii in long-term field experiments with sewage sludge cake, metal-amended liquid sludge or metal salts: Effects of zinc, copper and cadmium", Soil Biology & Biochemistry, 40, 1670-1680