Dirvos paruošimo įtaka žolinių augalų vystymuisi miško želdiniuose žemės ūkiui naudotuose plotuose ir kirtavietėse

Abstract

The influence of soil preparation on the development of ground vegetation during the establishment of forest plantations was studied. It was found that in the first-year plantations on former farmland the least biomass of ground vegetation develops on furrows. Complete soil tillage to the depth of 22-27 cm, ploughed in berms or elimination of weeds with Roundup Bio may reduce the biomass of ground vegetation by up to two times. Soil ploughing in berms or piles always reduced the mass of weeds.In the second year of plantations' growth, differences in the biomass of weeds among different soil preparation treatments decreased. On fresh clear-cut areas of fertile mineral soils any mechanical method of soil preparation reduced the biomass of ground vegetation. With increasing soil preparation depth (down to 40 cm) and the width of the strip (up to 100 cm), the biomass of ground vegetation decreased. The least (4-9 times less compared with unprepared soil) ground vegetation biomass was observed when the soil had been prepared in furrows, berms or piles. Soil preparation method affected also the height of ground vegetation. It depended on soil fertility and moisture content, weed species, spring and summer weather conditions. The shading class of seedlings and the volume of plantation tending depended on soil preparation method too. Seedlings planted on wide (100 cm) furrows and on 30 cm high piles were the least shaded, while those growing on unprepared, completely ploughed soil or on inverted humus mounds experienced the greatest suppression.

Influence of spot mounding on height growth and tending of Norway spruce: case study in Latvia

“…However, the actual mean projective cover of ground vegetation before the tending was signifi cantly higher in spot-mounded sites in comparison to disc-trenched sites: 78 and 54%, respectively. Earlier studies in similar climatic conditions had found, that soil preparation method determines the shading of seedlings and thus the need for tending; the least shaded were seedlings planted on wide (100 cm) furrows and 30 cm high mounds (Suchockas et al, 2014). So both of the soil preparation methods analysed in our study can yield similar results in relation to vegetation competition.…”

“…Similarly, grasses were the dominant ground vegetation type in second and third year after the clearcut in forest types on fertile soil also in Lithuania. Height of weeds were similar on ploughed berms and mounds (Suchockas et al, 2014). Grasses had been noted as most signifi cant competitors, capable to reduce height-growth of seedlings, primarily due to fast root growth and consequently intensive water uptake by graminoids (Coll et al, 2003).…”

“…Soil preparation increases the ground vegetation species richness (Balandier et al, 2006), but not necessarily its impact to seedlings. Impact of ground vegetation is related to its vicinity to the seedling and delayed by soil preparation depth and width (Suchockas et al, 2014).…”