Metal Amended Liquid Sludge Experiment
- Local identifier
- W/CS/428
- Years operational
- 1994—
- Objective
- To the effects of zinc, copper and cadmium on soil microbial activity with low organic matter inputs.
- Description
- Enables the comparison of metal concentrations (zinc, copper and cadmium) at 3 rates in small amounts of organic matter applied as a specially made liquid sludge applied. 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 3 sites across the UK and can also be compared with related Contaminated Sludge Cake Experiment and Metal Salts Experiment, also at Woburn.
- Data Access Statement
- Available to any researcher on request
- Data license
- CC BY
- Data policy
- Yes (not online)
- Organizations
- Rothamsted Researchresearch organisationWoburn Experimental Farmexperimental research station
- Person
- Prof. Steve McGrathprincipal investigatorRothamsted ResearchSustainable Agricultural Sciences
Site: Butt Close West
- Type
- research station field
- Location
- Husborne CrawleyHertfordshireUnited Kingdom
- Geographic location
- 52.01195, -0.597963
- Elevation
- 96 Metres
- Visits permitted?
- No
- Management
- Plots were bounded by wooden boards prevent soil movement during cultivation. Cultivations were carried out annually to ensure that the sludge additions were evenly incorporated in the top 0-25cm. The soil pH was maintained at 6.5.
- Soil type
- arenosol
- Soil properties
Variable Depth Value (range) Units Ref year Estimated? Baseline? sand content 0 – 25 Centimetres 83 Percent 1995 silt content 0 – 25 Centimetres 8 Percent 1995 clay content 0 – 25 Centimetres 9 Percent 1995 soil pH 0 – 25 Centimetres 7.3 1995 soil organic carbon 0 – 25 Centimetres 1.1 Percent 1995 - Climatic type
- temperate oceanic climate
Design period: (1995—)
- Design Type
- Randomized complete block design
- Description
- The metal amended sludges were prepared by mixing either zinc, copper or cadmium salts with a low metal content liquid digested sludge. . The sludges were applied for 3 years between 1995 and 1997. Plots measured 3.5 x 1.2m
- Design description
- Each plot received only one of the three metal amendments for 3 years between 1995 and 1997. In addition to the 9 treated plots there were 2 low metal content only sludge treatment plots and 2 untreated/no sludge control plots. All sludge treatments received the same organic matter loading.
- Number of blocks
- 3
- Number of plots
- 39
- Number of harvests per year
- 1
- Crop
Crop Years grown rye grass - Factors
- Factor name
- Factor levels
- zinc nutrient exposure Applied as liquid sludgePlot application: Whole plot
Rate 1 (348 kg/ha)
1995—1997Application frequency: annuallyRate 2 (696 kg/ha)
1995—1997Application frequency: annuallyRate 3 (1094 kg/ha)
1995—1997Application frequency: annually- copper nutrient exposure Plot application: Whole plot
Rate 1 (181 kg/ha)
1995—1997Application frequency: annuallyRate 2 (351 kg/ha)
1995—1997Application frequency: annuallyRate 3 (523 kg/ha)
1995—1997Application frequency: annually- cadmium exposure Plot application: Whole plot
Rate 1 (5.02 kg/ha)
1995—1997Application frequency: annuallyRate 2 (7.8 kg/ha)
1995—1997Application frequency: annuallyRate 3 (10.58 kg/ha)
1995—1997Application frequency: annually
Related publications
- Gibbs, P. A. , Chambers, B. J. , Chaudri, A. M. , McGrath, S. P. and Carlton-Smith, C. H. (2006) "Initial results from long-term field studies at three sites on the effects of heavy metal-amended liquid sludges on soil microbial activity", Soil Use and Management, 22, 180-187 https://doi.org/10.1111/j.1475-2743.2006.00009.x [In English]
- 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 https://doi.org/10.1016/j.soilbio.2008.01.026 [In English]