The aim of the paper is to point to the current structure and problems of agricultural production on hydroameliorated soils in the County of Zagreb. Based on the recognition of the causes of low economic effects, possibilities and prospects should be pointed out of further production on these areas (soils). The obtained results are mainly based on several year long stationary investigations, primarily of the functionality of the existing drainage systems and the achieved yields of the main agricultural crops. Investigations were carried out on several typical locations in the area of hydroameliorated soils in the County of Zagreb. Hydroameliorated - drained soils make up a considerable part of the total (8.64%), agricultural (15.69%) and arable (26.95%) land in the County of Zagreb. It should be noted that a large part (3.500 ha or 28%) of these land were left uncultivated in 1997. Most of these arable areas (96%) are used in agricultural production. Fruit growing accounts for only 3%, and the production of clover-grass mixture for negligible 1% of the overall production on these areas. Agricultural production is based on growing a few basic crops, in which participation of maize and wheat amounts to as much as 80% in some years. The remaining 20% areas are under oil rape, barley and soybean, the proportion of which has shown a sharp decrease in recent years. Results of several years of study point to considerable fluctuation in the yields of the mentioned crops, the average values being below those foreseen for conventional production. Analyses of the basic production indicators allow the conclusion that some financial profit may be realized on hydroameliorated areas (soils) in the production of maize, oil rape and wheat. Economic evaluation of investments into drainage of these soils and the realized economic effects of profitable crops, as well as the common credit conditions for such ameliorative practices also indicate that the remaining direct profit per unit area (1 ha) is barely sufficient to cover the annual costs of investment repayment. Causes of the low economic effects of the hydroameliorated areas in the County of Zagreb have to be sought for in the complex pedological - ameliorative problems related to these soils as well as the main characteristics of the existing hydroameliorative drainage systems. Unfortunately, the fact that the unfunctionality of the existing systems on most of the hydroameliorated - drained areas is the main cause of their low economic efficiency cannot be overlooked either. Unfunctionality, especially of the drainage systems, is further associated with the low efficiency of drainage, inadequate maintenance and inefficient land use, as well as inadequate surface systematization of arable land. Prospects of hydroameliorated - drained areas should be bases on: the strategy of long-term development of agriculture in the Republic of Croatia and the County of Zagreb, efficient use of hydroameliorated areas and revitalization of drainage systems. Agrarian policies should, therefore, be adjusted along these aims, as well as the concept of sustainable agriculture, in which the main characteristics of plant production will include procedures of sustainable land management together with the same system of plant nutrition and its integral protection.

soil; inklination; drainage; contact material; vertical soil loosening; soil moling; spacing

Published by University of Zagreb, Faculty of Agriculture, Zagreb, CROATIA
Sponsored by Ministry Science and Education of the Republic of Croatia