Field Experiments To Quantify The Agronomic Benefit Of Industrial Biowastes
Rigby, H. and Smith, S.R., Imperial College, London, UK
(free)
Organic residual materials produced by industrial processes, biowastes, are a valuable resource to agriculture in terms of
provision of N, P and K and inputs of trace elements and organic matter. However, the extensive range of processes that
produce these wastes means that their nutritional characteristics may be highly variable. Currently, approximately 7 million
tonnes of biowastes are recovered by land spreading in the UK. Quantitative research into the characteristics of biowastes
conferring agronomic benefit is essential to support their increasing use in agriculture. In addition, consideration of factors
that may influence nutrient availability of biowastes spread to land such as pre-treatment and length of storage is required. A
programme of field trials has been established at Imperial College London to provide information on the agronomic value of
a range of biowastes currently spread to land in the UK, results from the first year are presented. The field experiment uses
a systematic design and materials include examples of wastes from the vegetable, meat and dairy processing industries and
digested industrial biowastes from aerobic and anaerobic digestion plants. The yield response of perennial ryegrass to
application of biowastes at increasing rates, and the N fertiliser equivalency of these materials is presented. Factors
influencing the fertiliser value of industrial biowastes, and the strategic approach required in further investigation, are
discussed.
KEY WORDS
Agriculture, biowastes, commercial, industrial, fertiliser, land recovery, nitrogen, soil
