Žemdirbystės intensyvumo aplinkosauginis įvertinimas

Abstract

Straipsnyje pateikti apibendrinti medžiagų migracijos ryšio su agroekosistemos produktyvumu ir jį lemiančiais veiksniais tyrimų rezultatai

During the period 1995-1998, in Western Lithuania the Minija-Skinija basin the organic-biological and intensive cropping system on autonomous drainage plots in limed Bathihypogleyi-Albic Luvisol (LVa-gld-w), Dystri Endohypogleyic Combisol (CMg-n-w-dy) and non-acid Endocalcari Endohypogleyic Combisol (CMg-n-w-can soils were carried out in the system "soil-technology-water-plant". Cultivation of an intensive cropping system permits to receive a higher (by 38-76%) agroecosystem productivity as compared to organic-biological one. The drainage run-off depended on meterological conditions. Cultivation of intensive cropping system drainage runoff decreased by 6-57% as compared to organic-biological one. Cropping intensity has no influence on PO4 3- concentration and total mineral content in drainage and ground water. Under conditions of intensive cropping system, the concentration of NO3- in drainage water increased. A better efficiency of fertilization and higher yields decreased the nitrate concentration in drainage and ground water. The leached amounts of solutes depended upon drainage runoff volume and cropping intensity. Lower amounts of total mineral content and PO4 3- were leached under conditions of intensive cropping system. Nitrate leaching decreased with increasing fertilization efficiency. According ro these and other [3, 14] investigations, an intensive cropping system should not be considered a strong pollutant of a geosystem against an organic cropping system. However, the data of investigations show that fertilization recommendations in Lithuania insufficiently estimate the migration process of biogens. In order to reduce non-point source pollution of a geosystem, it should be aimed to reach maximum efficiency of fertilizers and to carry out other agricultural means irreproachably at the same time