Marginal abatement costs for reducing leaching of nitrates in Croatian agriculture

Authors

• J. SUMELIUS
• M. MESIC
• Z. GRGIC

DOI: https://doi.org/10.2137/145960605775013236

Abstract

The aim of this paper is to estimate marginal abatement costs (MAC) of N-fertiliser tax policies which aim to prevent NO3 levels from rising. Estimates of MAC provide information on how large reductions in Nfertilisation rates should be before other measures are considered. Based on N-response experiments from Croatian field trials with maize, N-response curves were estimated and profit maximising N-doses were derived. Values of NO3-N concentration in lysimeter water from the same treatments were used to estimate an NO3-leaching function. A sample of 20 Croatian family farms was used to obtain records of producer and input prices as well as actual N-doses. Abatement costs and MAC for an N-tax, a product tax and an Nquota were estimated. The MAC for all the instruments are non-constant and increase at an accelerating rate. The MAC for N-taxes are positive for N-taxes lower than 60%, indicating a net return to society. Reduction rates in fertilisation up to this level should be achieved before considering governmental support for other measures. The N-tax has the lowest abatement cost and the lowest MAC for a particular level of reduction while the N-quota has a lower MAC than the product tax when total reduction levels are below 20 mg NO3 l-1.;