The natural recovery of disturbed soil, plant cover and trees after clear-cutting in the boreal forests, Russia

Abstract

Biogeosciences and Forestry Biogeosciences and Forestry The natural recovery of disturbed soil, plant cover and trees after clear-cutting in the boreal forests, Russia Aleksey Ilintsev (1-2) , Alexander Bogdanov (1-2) , Elena Nakvasina (2) , Irina Amosova (3) , Sergey Koptev (2) , Sergey Tretyakov (2) This study aims to determine the impact of forest harvesting machinery on the temporarily moist soil of spruce forests (Picea abies Karst.) during the summer. For research purposes, we investigated 23 sites of the boreal forest in the European North of Russia (Arkhangelsk region) where logging operations had been carried out using harvesters and forwarders (CTL, cut-to-length harvesting). In the 15 years after logging, the sites were monitored for changes in physical soil properties and the depth/width of ruts and vegetation. In freshly cut areas, the depth of the ruts was linked to the amount of logging residue that had been used to strengthen skidding trails. After 15 years, the ruts were smooth but had not disappeared entirely. The average depth of the ruts decreased from 36 cm to 18 cm during the period under review. At a depth of 0-10 cm, the soil bulk density of the section between the control area and the wheel track increased by 19-27% within the first two years. At a depth of 10-20 cm, the soil bulk density only increased by 16-17% within the two-year period. After 15 years, the soil bulk density had decreased to the extent that there were no signs of heavy machinery movement. The natural restoration of vegetation in the ruts was affected by the presence of stagnant water in the initial post-logging period. Ruderal species and species with broad ecological amplitude to environmental factors grew over the skid trails. 15 years after logging, this overgrowth had stabilised, with the biodiversity level in the control area approaching its pre-logging state. Primarily, the renewal of the cutting areas occurred through species such as birch (Betula pendula Roth.) and aspen (Populus tremula L.). The highest amount of undergrowth (more than 30,000 ha-1) was detected 6-8 years after logging. This then decreases in areas that were cut down earlier. There are environmental consequences of clearcutting (using the CTL system) on temporarily moist soil. To prevent the formation of deep ruts, it is recommended to leave 15-20 kg m-2 of felling residue.

Natural Regeneration of the Tree Stand in the Bilberry Spruce Forest—Clear-Cutting Ecotone Complex in the First Post-Logging Decade

“…The study of the regeneration distribution over the EC and its determinant factors confirmed our previous findings [31] of the four distinct zones: forest, a transition from forest to clear-cut under forest canopy, a transition from forest to clear-cut beyond forest scant in the surveyed stands, it does populate clear-cuts very actively, propagating by root sprouts and seeds [56]. Prickly rose, like rowan, is a widespread understory species but is more light-demanding [57] and forms single-species stands in open sites.…”

“…Birch is known for frequent and abundant seed-bearing and intensive growth [58,59]. It can, therefore, rapidly capture the released spaces, occupying the dominant position [56]. Another factor is its capacity for vegetative propagation-after a stand comprising birch is logged down, birch begins to regenerate rapidly and grow actively [60].…”

Ground vegetation, forest floor and mineral topsoil in a clear-cutting and reforested Scots pine stands of different ages: a case study

“…This suggests that reforested sites could recover during the first 30-year period. Previous studies found that different types of silvicultural management highly modify ground vegetation, even under the same tree species (Tyle 1989;Ilintsev et al 2020;Marozas and Sasnauskienė 2021). For example, shelter wood cuttings in Scots pine stands resulted in an increase of herbaceous species but decreased the abundance of mosses and lichens (Marozas and Sasnauskienė 2021).…”

“…It was also noticed that species richness increased after clear-cutting. Changes in microenvironmental conditions create new ecological niches that lead to changes in plant cover and composition and the emergence of different ecological cenotic groups (Ilintsev et al 2020).…”

“…It can be argued hypothetically that differences from the mature stand should continue for a limited time. If changes in ground vegetation indices could be detected soon after clear-cutting (Česonienė et al 2019;Stefańska-Krzaczek et al 2019;Ilintsev et al 2020), changes in the soil could be less noticeable. An exception is a post-harvest peak in nitrate concentrations in runoff water which is caused by more intensive mineralization of organic matter in the clearcuttings (Bergholm et al 2015;Armolaitis et al 2018).…”