Can increased weathering rates due to future warming compensate for base cation losses following whole-tree harvesting in spruce forests?

Abstract. Soil and water acidification was internationally recognised as a severe environmental problem in the late 1960s. The interest in establishing “critical loads” led to a peak in weathering research in the 1980s and 1990s, since base cation weathering is the long-term counterbalance to acidification pressure. Assessments of weathering rates and associated uncertainties have recently become an area of renewed research interest, this time due to demand for forest residues to provide renewable bioenergy. Increased demand for forest fuels increases the risk of depleting the soils of base cations produced in situ by weathering. This is the background to the research programme Quantifying Weathering Rates for Sustainable Forestry (QWARTS), which ran from 2012 to 2019. The programme involved research groups working at different scales, from laboratory experiments to modelling. The aims of this study were to (1) investigate the variation in published weathering rates of base cations from different approaches in Sweden, with consideration of the key uncertainties for each method; (2) assess the robustness of the results in relation to sustainable forestry; and (3) discuss the results in relation to new insights from the QWARTS programme and propose ways to further reduce uncertainties. In the study we found that the variation in estimated weathering rates at single-site level was large, but still most sites could be placed reliably in broader classes of weathering rates. At the regional level, the results from the different approaches were in general agreement. Comparisons with base cation losses after stem-only and whole-tree harvesting showed sites where whole-tree harvesting was clearly not sustainable and other sites where variation in weathering rates from different approaches obscured the overall balance. Clear imbalances appeared mainly after whole-tree harvesting in spruce forests in southern and central Sweden. Based on the research findings in the QWARTS programme, it was concluded that the PROFILE/ForSAFE family of models provides the most important fundamental understanding of the contribution of weathering to long-term availability of base cations to support forest growth. However, these approaches should be continually assessed against other approaches. Uncertainties in the model approaches can be further reduced, mainly by finding ways to reduce uncertainties in input data on soil texture and associated hydrological parameters but also by developing the models, e.g. to better represent biological feedbacks under the influence of climate change.

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Potential impact of forest harvesting on lake chemistry in south-central Ontario at current levels of acid deposition

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f03-093 ◽

2003 ◽

Vol 60 (9) ◽

pp. 1095-1103 ◽

Cited By ~ 45

Author(s):

S A Watmough ◽

J Aherne ◽

P J Dillon

Keyword(s):

Critical Load ◽

Base Cation ◽

Forest Harvesting ◽

Lake Chemistry ◽

South Central ◽

Sulphate Deposition ◽

Potential Impact ◽

Whole Tree Harvesting ◽

Whole Tree ◽

Tree Harvesting

The potential impact of harvesting on lake chemistry was assessed for ~1300 lakes in south-central Ontario using a critical loads approach based on the steady-state water chemistry (SSWC) model. The critical load of acidity is currently only exceeded by bulk sulphate deposition in 9% of the lakes if harvesting does not occur. However, the percentage increases to 23%, 56%, and 72% under potential harvesting scenarios that assume wood-only (stem without bark), stem-only, or whole-tree harvesting, respectively. This increase in exceedance of critical load is due to the much lower base cation concentrations in lakes resulting from base cation removals during harvest. For example, only 0.3% of lakes will have Ca2+ concentrations <50 μequiv.·L1 if harvesting does not occur, whereas 52% of lakes will have Ca2+ concentrations <50 μequiv.·L1 if whole-tree harvesting occurs. Harvesting clearly has an enormous potential impact on lake chemistry, which will become more apparent as exchangeable base cation pools in soil decline and acid inputs can no longer be buffered.

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Soil carbon, nitrogen, and base cation cycling 17 years after whole-tree harvesting in a low-elevation red spruce (Picea rubens)-balsam fir (Abies balsamea) forested watershed in central Maine, USA

Forest Ecology and Management ◽

10.1016/j.foreco.2005.10.033 ◽

2006 ◽

Vol 222 (1-3) ◽

pp. 234-253 ◽

Cited By ~ 37

Author(s):

James W. McLaughlin ◽

Stephanie A. Phillips

Keyword(s):

Soil Carbon ◽

Abies Balsamea ◽

Base Cation ◽

Picea Rubens ◽

Red Spruce ◽

Balsam Fir ◽

Forested Watershed ◽

Whole Tree Harvesting ◽

Whole Tree ◽

Tree Harvesting

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Weathering rates in Swedish forest soils

10.5194/bg-2019-1 ◽

2019 ◽

Author(s):

Cecilia Akselsson ◽

Salim Belyazid ◽

Johan Stendahl ◽

Roger Finlay ◽

Bengt Olsson ◽

...

Keyword(s):

Forest Soils ◽

National Level ◽

Base Cations ◽

Research Programme ◽

Sustainable Forestry ◽

Forest Fuels ◽

Weathering Rates ◽

Whole Tree Harvesting ◽

Whole Tree ◽

Tree Harvesting

Abstract. Soil and water acidification was first recognised as a severe environmental problem in the 1970s. The interest in establishing critical loads led to a peak in weathering research in the 1980s, since weathering is the long-term counterbalance to acidification pressure. Assessments of weathering rates and associated uncertainties have recently become an area of renewed research interest, this time due to demand for more harvest to provide renewable bioenergy. Increased demand for forest fuels increases the risk of depleting the soils of base cations produced in situ by weathering. This is the background to the research programme Quantifying Weathering Rates for Sustainable Forestry (QWARTS), which ran from 2012 to 2019. The programme involved research groups working at different scales, from lab experiments to extensive modelling. The aims of this paper are to summarise the state of knowledge about weathering rates in Swedish forest soils at different scales, with an emphasis on the knowledge added by the QWARTS programme, to discuss the uncertainties in relation to sustainable forestry, and to highlight knowledge gaps where further research is needed. The variation at single-site level was large, but most sites could be placed reliably in broader classes of weathering rates. At regional to national level, the results from the different approaches were in general agreement. Comparisons of base cation losses after stem-only and whole-tree harvesting showed sites with clear imbalances between weathering supply and harvest losses, and other sites where variation in weathering rates from different approaches obscured the overall balance. Clear imbalances appeared mainly after whole-tree harvesting in spruce forests in southern and central Sweden. Research findings in the QWARTS programme support the continued use of the PROFILE/ForSAFE family of models, but it is important to continue comparisons between these and other approaches. Uncertainties in the model approaches can be further reduced, mainly by finding ways to reduce uncertainties in input data on soil texture and associated hydrological parameters. Another way to reduce uncertainties is by developing the models to better represent the delivery of weathering products to runoff waters and biological feedbacks under the influence of climate change.

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Regional modelling of base cation losses from Swedish forest soils due to whole-tree harvesting

Applied Geochemistry ◽

10.1016/s0883-2927(09)80035-8 ◽

1993 ◽

Vol 8 ◽

pp. 189-194 ◽

Cited By ~ 54

Author(s):

M. Olsson ◽

K. Rosén ◽

P.-A. Melkerud

Keyword(s):

Forest Soils ◽

Base Cation ◽

Regional Modelling ◽

Whole Tree Harvesting ◽

Whole Tree ◽

Tree Harvesting

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Modelling the effects of forest management intensification on base cation concentrations in soil water and on tree growth in spruce forests in Sweden

European Journal of Forest Research ◽

10.1007/s10342-021-01408-6 ◽

2021 ◽

Author(s):

Giuliana Zanchi ◽

Klas Lucander ◽

Veronika Kronnäs ◽

Martin Erlandsson Lampa ◽

Cecilia Akselsson

Keyword(s):

Soil Water ◽

Soil Solution ◽

Tree Growth ◽

Nitrogen Availability ◽

Base Cation ◽

Forest Residues ◽

Forest Sites ◽

Whole Tree Harvesting ◽

Whole Tree ◽

Tree Harvesting

AbstractThe study investigated the effects of forest residue extraction on tree growth and base cations concentrations in soil water under different climatic conditions in Sweden. For this purpose, the dynamic model ForSAFE was used to compare the effects of whole-tree harvesting and stem harvesting on tree biomass and the soil solution over time at 6 different forest sites. The study confirmed the results from experimental sites showing a temporary reduction of base cation concentration in the soil solution for a period of 20–30 years after whole-tree harvesting. The model showed that this was mainly caused by the reduced inputs of organic material after residue extraction and thereby reduced nutrient mineralisation in the soil. The model results also showed that whole-tree harvesting can affect tree growth at nitrogen-poor forest sites, such as the ones in northern Sweden, due to the decrease of nitrogen availability after residue removal. Possible ways of reducing this impact could be to compensate the losses with fertilisation or extract residue without foliage in areas of Sweden with low nitrogen deposition. The study highlighted the need to better understand the medium- and long-term effects of whole-tree harvesting on tree growth, since the results suggested that reduced tree growth after whole-tree harvesting could be only temporary. However, these results do not account for prolonged extraction of forest residues that could progressively deplete nutrient pools and lead to permanent effects on tree growth.

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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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Whole-tree Harvesting Depletes Soil Nutrients

Canadian Journal of Forest Research ◽

10.1139/x74-077 ◽

1974 ◽

Vol 4 (4) ◽

pp. 530-535 ◽

Cited By ~ 39

Author(s):

Edwin H. White

Keyword(s):

Soil Nutrients ◽

Nutrient Removal ◽

Cropping Systems ◽

Soil Nutrient ◽

Site Conditions ◽

Nutrient Pool ◽

Whole Tree Harvesting ◽

The Impact ◽

Whole Tree ◽

Tree Harvesting

This paper reports the effects of whole-tree harvesting of eight cottonwood stands on the soil nutrient pool. The data indicate possible site degradation by depletion of soil reserves of N, P, and K but not Ca and Mg on a range of alluvial site conditions in Alabama. Foresters must establish the rate of nutrient removal in intensive tree cropping systems for a variety of species and sites and develop prescriptions to minimize the impact.

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