Initial evaluation of impact of evenness of spreading wood ash in forest on additional radial increment

Abstract

Abstract. One of the most feasible options for utilization of wood ash obviously is to improve the forest growth conditions, particularly in fertilization of drained forests and peatlands, where the positive impact on tree growth response is observed by many studies in boreal and temperate moist climate zone. Forest fertilization as forestry measure meets several obstacles. One of the main is evenness of mechanized spreading, which is affected by the strip road configuration and stand density. It is also difficult to provide even spread of ash because of variable texture if untreated ash is used. The aim of this study is to determine how far from the fertilized area tree growth is affected. Experiment was established in 3 Norway spruce stands on drained forest soils. In each stand 9 systematically located 20×20 m sample plots were set. Tree measurements were made before fertilization and increment cores were collected 5 growing seasons after fertilization from trees in the sample plots and trees in different distances from the sample plots to determine annual radial increments. Cumulative additional radial increment varied from 0.95 to 3.58 mm in the ash fertilized plots. Significant and positive (t = 4.68 > t 0.05;37 = 1.69) effect of wood ash in outer 10 m zone of the fertilized plots was observed only in 1 spruce stand, which could be partly explained by leaching of biogenic elements and distribution of roots.

Review of climate change mitigation measures applicable in degraded peatlands in Latvia

“…(Bērziņa et al, 2018). Fertilization increases N 2 O emissions from soil; however, this effect is far less than the net removals (Okmanis et al, 2018;Petaja et al, 2018). No support is considered for fertilization in national legislation; however, it is not restricted either.…”

“…Wood ash recycling is another type of fertilization, which can be combined with mineral fertilizers to substitute expensive P and K mineral fertilizers and can be added alone in moderately rich soils not suffering from shortage of nitrogen. Linear additional increment (around 15 m 3 ha -1 per treatment) is considered in several studies assuming that the forest management is optimized to ensure the additional increment (Okmanis et al, 2018;Okmanis, Lazdiņš et al, 2015;Okmanis, Polmanis et al, 2015). There are no models elaborated for Latvia to estimate impact of changes in the forest management; therefore, only a short term impact is considered.…”

The Impact of Forest Fertilization on the Ecological Quality of Two Hemiboreal Streams

“…Local studies have reported the positive impact of wood ash on the radial increment of hybrid aspen plantation [11] in the first 1-2 years and additional radial increment in Forests 2022, 13,196 2 of 15 middle-aged Norway spruce stands [12] 5 years after soil improvement with fertilizers. Recent studies have also shown the impact of fertilization on soil organic carbon stock and chemical properties of the soil, groundwater, and stem wood [13][14][15].…”

Soil carbon stock in fertilized forest stands with mineral soils

“…Forest fertilization can be commenced during the whole rotation or 10-15 years before the regenerative felling, respectively, forest fertilization can be conducted once during the rotation period or can be repeated to ensure continuously high growth rates (Högberg et al, 2006). Studies in Latvia have reported a short-term impact of forest soil fertilization with wood ash on the growth of stand (Okmanis et al, 2016;Okmanis et al, 2018) while other studies reported a long-term effect of forest soil fertilization on growth of trees (Jansons et al, 2016;Libiete et al, 2016;Petaja et al, 2018).…”