THE EFFECTS OF SOIL MANAGEMENT SYSTEMS IN ORCHARDS IN THE CHERNOZEMS OF THE EASTERN PART OF DOBROGEA PUBLISHEDC. PĂLTINEANU1, Leinar SEPTAR2, Irina CALCIU1, Olga VIZITIU1, Mihaela LUNGU1
Abstract . The calcaric chernozems from orchards in the eastern part of Dobrogea were less studied by now from the view point of soil physical properties. The purpose of this paper is therefore to show the physical state of the chernozems from the eastern part of Dobrogea as effect of the specific orchard tillage practices after a few decades of intensive activity. Soil samples were taken from both between tree rows (ITR) and in the rows (IR). It was found that soil physical properties worsened in ITR versus IR, and this was attributed to the compaction caused by the specific fruit growing technological traffic. Bulk density (BD), macroporosity (P50), resistance to penetration (RP) and saturated hydraulic conductivity (Ksat) showed significant differences between ITR and IR in some soil layers. The soil compaction degree (GT) values revealed the fact that only the upper part of the soil profiles having direct or close contact with the agricultural machinery and tractors underwent a moderate soil compaction. The present practical recommendations for orchard establishing for a large area of more clayey and compacted soils from the hilly regions of Romania were to plow deeply the soils at 0.5-0.6 m depth. Having done this way in the cherozems of Dobrogea, it would bring carbonates upper and humus and the nutrients deeper in the soil, and would also change the chemical reaction towards alkalinization in the Am layers, where most of the tree roots exist. Deep plowing would also cut additionally the soil structural elements and would worsen the soil structure as well. In order to improve the physical state of the chernozems of Dobrogea it is recommended to deep loosen the soil at the end of orchard life from the reasons of clearing the soil, and also to penetrate the compacted soil layers without overturning the soil, followed by cropping some ameliorative plants like alfalfa, peas or other such crop for a few years. When new orchards are established, the fruit tree rows (IR) should be placed over ITR positions and vice versa, if possible, to alleviate the soil fatigue.
Key words: inter-row, in-row, soil compaction, bulk density