Nitrogen mineralization and vegetation along skidding tracks

Abstract

-Forest management requires a dense forest road system which combines truck roads and skidding tracks. However, harvesting machines cause damage to forest stands and soils. The aim of this study is to examine the consequences skidding tracks have on net nitrogen mineralization and vegetation composition compared to adjacent forest stands. A beech forest on limestone as well as beech and Norway spruce forests on acidic soils were investigated in south Lower Saxony, Germany. Along the wheel tracks the net nitrogen mineralization is markedly reduced compared to the undisturbed stands. Although nitrogen mineralization is found to be low especially along the wheel tracks, ruderal plants with high nitrogen indicator values have established themselves. Along the skidding tracks, numerous species from fringe and ruderal communities, grasslands and wet sites occur while the stands are dominated by typical forest plant species. Therefore, species diversity is higher along the skidding tracks than in the adjacent stands.

Canopy effects on vegetation caused by harvesting and regeneration treatments

“…The influence of nutrient availability on primary production and the structure and diversity of plant communities has been demonstrated in many communities along soil fertility and/or soil moisture gradients (Tilman and Wedin 1991;Briggs and Knapp 1995;Ebrecht and Schmidt 2003). Effects of soil resource limitations are more pronounced in soils with low fertility, where biomass production is low and plant communities are dominated by a smaller number of species using the most limiting resources more efficiently (Mamolos et al 1995).…”

“…Yet, some additional factors do influence distribution, evenness and diversity of understorey plants in temperate forests, notably edaphic conditions (Gilbert and Lechowicz 2004;Hofmeister et al 2009), human activity (Ebrecht and Schmidt 2003;Godefroid and Koedam 2004) or former land-use (Fraterrigo et al 2006). …”

Effects of soil surface disturbances after logging on plant functional types

“…However, even if species richness decreases, rare species can develop in old forests and thus yield enhanced conservation value [11,61]. Logging changes canopy structure and induces large understorey modifications with regards to light [21,67], rainfall distribution on soil [1,10], temperature and humidity [9], as well as chemical and microbiological soil properties [18,37,44,51]. All these factors have effects on species diversity and thus on resistance [43], resilience [58] and overall functioning of ecosystems.…”

Developing site disturbance standards in Ontario: Linking Science to Forest Policy within an Adaptive Management Framework

“…Topics covered root and bark Although there is a considerable amount of literature related to soil disturbance, the majority of studies have focused on the effects of compaction, with only a limited number that have specifically examined rutting. These compaction studies have examined its effect on the physical properties of soils (Holman et al 1978;AbuHamdeh et al 2000;House et al 2001;Miller et al 2004), impacts on soil quality (Lipiec and Stepniewski 1995;Jensen et al 1996;Pennock and van Kessel 1997;Ebrecht and Schmidt 2003;Kranabetter and Sanborn 2003), and its effects on regeneration potential and plant growth (Perry 1964;Corns 1988;Farrish et al 1995;Groot 1998;Kozlowski 1999;Brais 2001;Stone and Kabzems 2002). The difficulty here is that compaction is not easily measured, requires many samples to accurately assess its impact at the stand level, and is difficult to separate from other forms of soil disturbance (e.g., displacement).…”