Spruce forest afforestation leading to increased Fe mobilization from soils

AbstractIncreasing exports of Fe and DOC from soils, causing browning of freshwaters, have been reported in recent decades in many regions of the northern hemisphere. Afforestation, and in particular an increase of Norway spruce forest in certain regions, is suggested as a driver behind these trends in water chemistry. In this study, we tested the hypothesis that the gradual accumulation of organic soil layers in spruce forests, and subsequent increase in organic acid concentrations and acidity enhances mobilization of Fe. First generation Norway spruce stands of different ages (35, 61, 90 years) and adjacent arable control plots were selected to represent the effects of aging forest. Soil solutions were sampled from suction lysimeters at two depths (below organic soil layer and in mineral soil) during two years, and analyzed for Fe concentration, Fe speciation (XAS analysis), DOC, metals, major anions and cations. Solution Fe concentrations were significantly higher in shallow soils under older spruce stands (by 5- and 6-fold) than in control plots and the youngest forest. Variation in Fe concentration was best explained by variation in DOC concentration and pH. Moreover, Fe in all soil solutions was present as mononuclear Fe(III)-OM complexes, showing that this phase is dominating Fe translocation. Fe speciation in the soil was also analyzed, and found to be dominated by Fe oxides with minor differences between plots. These results confirmed that Fe mobilization, by Fe(III)-OM complexes, was higher from mature spruce stands, which supports that afforestation with spruce may contribute to rising concentrations of Fe in surface waters.

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The effects of afforestation on Fe mobilization in soils and potential for leaking into surface waters

10.5194/egusphere-egu2020-20462 ◽

2020 ◽

Author(s):

Martin Škerlep ◽

Ulf Johansson ◽

Dan Berggren Kleja ◽

Per Persson ◽

Emma S Kritzberg

Keyword(s):

Soil Water ◽

Northern Hemisphere ◽

Surface Waters ◽

Mineral Soil ◽

Coniferous Forest ◽

Organic Soil ◽

Soil Horizon ◽

Societal Implications ◽

Spruce Stands ◽

Fe Speciation

Increasing surface water concentrations of Fe and DOC (browning), have been reported around the northern hemisphere in the last couple of decades. This increase has far-reaching ecological and societal implications, as it alters the light climate in water and decreases the quality of drinking water. One of the hypothesis behind the increase has been that afforestation and a dominance of coniferous forest have increased the availability of Fe and DOC for transport from soils into surface waters. The accumulation of organic soil layers in coniferous forests increases acidity and the amounts of organic acids in soils and may thus enhance weathering, solubility and mobilization of Fe as the forest ages. In this study we examined the effects of afforestation and growth of Norway spruce on the mobilization and potential leakage of Fe and DOC from soils to surface waters. To represent the effects of ageing forest we used plots with spruce stands of different ages (35, 61, 90 years) and unforested control plots in their immediate proximity, in T&#246;nnersj&#246;heden experimental forest (Sweden). Soil water collected in lysimeters (installed below the organic horizon and in the mineral soil) and analyzed for Fe, Fe speciation, using X-ray absorption spectroscopy (XAS), as well as DOC, metals, major anions and cations. Soil samples were analyzed for Fe speciation and crystallinity at different depths. Results from the soil water analysis show that more Fe was mobile in older spruce forest stands with higher DOC concentrations and lower pH. Covariation of Fe and DOC concentrations in soil waters, indicate the dependence of Fe on DOC to solubilize and stay in solution. Preliminary results from our XAS analysis also indelicate a considerable amount of Fe(II) in soil water that is likely stabilized from oxidation by organic complexation. Surprisingly Fe extracted from the organic (O) soil horizon showed the highest crystallinity and crystallinity did not vary much between soils of different stand ages. &#160;The results of this study indicate that afforestation promotes Fe and DOC availability for export into surface waters as well as strengthens the notion that the effects of afforestation are not immediate, but take time as soils develop slowly. As afforestation and dominance of coniferous forest continues in many parts of the northern hemisphere, we can expect further increase of Fe and DOC in surface waters.

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Natural 15N abundance in two nitrogen saturated forest ecosystems at Solling, Germany

Journal of Forest Science ◽

10.17221/4794-jfs ◽

2012 ◽

Vol 49 (No. 11) ◽

pp. 515-522 ◽

Cited By ~ 8

Author(s):

S. P Sah ◽

R. Brumme

Keyword(s):

Soil Water ◽

Soil Depth ◽

Mineral Soil ◽

Soil Layer ◽

Organic Soil ◽

Soil Horizon ◽

Nitrification Rate ◽

Seepage Water ◽

Natural Occurrence ◽

N Enrichment

This research deals with a comparative study of two different N-saturated forests: 1. beech forest and 2. spruce forest at the same locality of \solling, Central Germany. The present results show that 15N natural occurrence in the rainfall (both above and below canopy) at Solling site is similar (δ15N = –15&permil; to +19&permil;) to other sites of the world (such as NITREX sites, USA etc.). Furthermore, 15N values in the soil water ranged from –4.32 (± 2.09) to +5&permil; (± 1.47), which also corresponds to NITREX sites and other sites of Europe and USA. In both forests, δ15N enrichment of both NH4-N and NO3-N showed a decreasing trend of their values from bulk precipitation to the upper soil layer, but increasing in the deeper soil layer again. An increase in the 15N enrichment of soil water from upper soil depth to lower soil depth was observed in our study and it is assumed to be due to the strong net nitrification taking place in the upper layer (organic surface layer) of soil. The soils at both sites showed characteristic low (negative) δ15N values in the upper organic layers, strongly increasing to positive δ15N values in the mineral soil. In the lower depths of mineral soil horizons of both stands, an increase in δ15N values was found to culminate at +3 to +5&permil;. In contrast to the mineral soil horizon, in the organic soil horizon (0 to 6 cm depth) of both sites there was almost a similar or slight decrease in δ15N values with depth. This is attributed to the high nitrification rate in the organic soil horizon, resulting in excessive seepage water NO3-output at both sites (especially at the spruce site).

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Findings regarding ectotrophic stability of Norway spruce forest of the Krkonoše and Orlické Mountains based on mycorrhiza studies

Journal of Forest Science ◽

10.17221/139/2010-jfs ◽

2011 ◽

Vol 57 (No. 11) ◽

pp. 500-513

Author(s):

V. Pešková ◽

J. Landa ◽

F. Soukup

Keyword(s):

Species Composition ◽

Norway Spruce ◽

Forest Soils ◽

Agricultural Soils ◽

Data Series ◽

Spruce Forest ◽

Fruiting Bodies ◽

Spruce Stands ◽

Norway Spruce Forest

 Analyses of root mycorrhizal samples and monitoring of fruiting bodies of macromycetes from Norway spruce stands at mountain and foothill localities in the Krkono&scaron;e and Orlické Mts. provided several data series allowing to assess and compare (albeit somewhat preliminarily) mycorrhizal conditions and macromycete incidence related to stand ages and  location conditions. The overall mycorrhizal conditions in young (10 years old) and older (80 years old) stands on formerly agricultural soils are comparable to those in 80- and 90-year-old forests growing on standard forest soils, but young spruce stands in the Orlické Mts. replanted on forest soils do not surprisingly show any favourable mycorrhizal characteristics. The research documents a marked diversity of macromycete species composition in mountain spruce stands compared to foothill spruce stands on former agricultural soils. While in the younger mountain spruce stands of the Orlické Mts. the expansion of macromycete species composition began to develop in a similar fashion to that in the Krkono&scaron;e Mts., the comparison of older (80-year-old) stands on formerly agricultural soils in the Orlické Mts. foothills and Krkono&scaron;e Mts. implies that the macromycete species composition developed quite differently but with a similar success.

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Adsorption of dissolved nitrogen by forest mineral soils

Canadian Journal of Forest Research ◽

10.1139/x09-147 ◽

2009 ◽

Vol 39 (12) ◽

pp. 2381-2390 ◽

Cited By ~ 22

Author(s):

D.N. Kothawala ◽

T.R. Moore

Keyword(s):

Soil Properties ◽

Dissolved Organic Nitrogen ◽

Organic Nitrogen ◽

Mineral Soil ◽

Organic Soil ◽

Nutrient Sources ◽

Dissolved Nitrogen ◽

Soil Solutions ◽

Mineral Soils ◽

Similar Soil

Dissolved nitrogen (N) species, including ammonium (NH4+-N), nitrate (NO3–-N), and dissolved organic nitrogen (DON), are important nutrient sources in soils. The mobility of DON and NH4+-N in soil solutions is influenced by abiotic adsorption to mineral soil particle surfaces. We determined relationships between soil properties and their ability to adsorb NH4+-N, NO3–-N, and DON, using batch experiments. A range of 41 mineral horizons was collected from across Canada, including Podzols, Brunisols, Luvisols, Gleysols, and an organic soil. The adsorption of DON and dissolved organic carbon (DOC) were positively correlated (R2 = 0.86), and both were best explained by the amount of iron and aluminum associated with poorly crystalline phases. Adsorption of NH4+-N was strongest in Gleysols and Luvisols, while adsorption of NO3–-N was weak in all soils. A reduction in the DOC:DON ratio was observed for most mineral horizons (89%) after equilibration from an original ratio of 35:1. Mineral horizons with a net desorption of DON had a significantly greater reduction in the final DOC:DON ratios than horizons with a net adsorption of DON. The results from this study found that while similar soil properties could predict DOC and DON adsorption, DON was slightly more mobile than DOC.

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Bucheckern-Voraussaat unter Fichtenschirm - Ergebnisse eines Versuchs des Deutschen Verbandes Forstlicher Forschungsanstalten/Sektion Waldbau -. Direct Seeding of European Beech (Fagus sylvatica L.) in Pure Norway Spruce Stands (Picea abies [L.] Karst.) - Results of an Experiment by the German Union of Forest Research Organizations/Silviculture Division -

Forftwiffenfchaftliches Centralblatt ◽

10.1046/j.1439-0337.2003.00160.x ◽

2003 ◽

Vol 122 (3) ◽

pp. 160-174 ◽

Cited By ~ 4

Author(s):

Bertram Leder ◽

Sven Wagner ◽

Jorg Wollmerstadt ◽

Christian Ammer

Keyword(s):

Picea Abies ◽

Norway Spruce ◽

Fagus Sylvatica ◽

European Beech ◽

Direct Seeding ◽

Forest Research ◽

Research Organizations ◽

Spruce Stands ◽

Fagus Sylvatica L

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Imitated Whole Tree Harvesting Show Negligible Effect on Economic Value of Spruce Stands

Forests ◽

10.3390/f12070841 ◽

2021 ◽

Vol 12 (7) ◽

pp. 841

Author(s):

Iveta Desaine ◽

Annija Kārkliņa ◽

Roberts Matisons ◽

Anna Pastare ◽

Andis Adamovičs ◽

...

Keyword(s):

Norway Spruce ◽

Economic Value ◽

Forest Types ◽

Spruce Stands ◽

The Difference ◽

Growing Conditions ◽

Whole Tree Harvesting ◽

Whole Tree ◽

Tree Harvesting

The increased removal of forest-derived biomass with whole-tree harvesting (WTH) has raised concerns about the long-term productivity and sustainability of forest ecosystems. If true, this effect needs to be factored in the assessment of long-term feasibility to implement such a drastic forest management measure. Therefore, the economic performance of five experimental plantations in three different forest types, where in 1971 simulated WTH event occurred, was compared with pure, planted and conventionally managed (CH) Norway spruce stands of similar age and growing conditions. Potential incomes of CH and WTH stands were based on timber prices for period 2014–2020. However, regarding the economics of root and stump biomass utilization, they were not included in the estimates. In any given price level, the difference of internal rate of return between the forest types and selected managements were from 2.5% to 6.2%. Therefore, Norway spruce stands demonstrate good potential of independence regardless of stump removal at the previous rotation.

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A Novel Approach to Evaluate the Effect of Neighboring Trees and the Orientation of Tree Social Area on Stem Radial Increment of Norway Spruce Trees

Forests ◽

10.3390/f12020163 ◽

2021 ◽

Vol 12 (2) ◽

pp. 163

Author(s):

Jan Světlík ◽

Jan Krejza ◽

Pavel Bednář

Keyword(s):

Norway Spruce ◽

Tree Growth ◽

Growth Models ◽

Explanatory Power ◽

Radial Increment ◽

Important Indicator ◽

The Czech Republic ◽

Novel Approach ◽

Spruce Stands ◽

Social Area

Tree growth depends on many factors such as microsite conditions, vitality, and variations in climate and genetics. It is generally accepted that higher growth indicates both an economic benefit and better vitality of any tree. Here we use a modified approach of evaluating tree social area to study mutual tree competition based on the orientation and shape of trees social area. The investigation was performed in nine Norway spruce stands in the Czech Republic. The objective of this study performed from 2008 to 2012 was to quantify relative tree radial increments with respect to the lowest and highest competition found in specific sectors of tree social area (AS). Specific groups of trees (tree classes) were evaluated according to their classes (dominant, co-dominant and sub-dominant) and their composition status in ninety-degree sectors of AS using established classifying rules. The results showed that a spatially-available area (AA) is an inappropriate parameter for predicting tree growth, whereas AS provided robust explanatory power to predict relative radial growth. Tree size was observed as an important indicator of relative radial increments. A significantly positive correlation was found for a radial increment of sub-dominant trees with the lowest competition from western directions; whereas a negative correlation was observed when the lowest competition was observed from eastern directions. For dominant trees, there was an evident growth reaction only when more than 50% of the AS was oriented towards one of the cardinal points. Individual differences in the orientation of tree AS may be important parameters with regard to competition and its spatial variability within an area surrounding a particular tree and deserve more detailed attention in tree growth models and practice.

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