This page has only limited features, please log in for full access.

Unclaimed
Tobias Bölscher
Department of Soil and Environment, Swedish University of Agricultural Sciences, P.O. Box 7014, SE-750 07 Uppsala, Sweden

Basic Info

Basic Info is private.

Honors and Awards

The user has no records in this section


Career Timeline

The user has no records in this section.


Short Biography

The user biography is not available.
Following
Followers
Co Authors
The list of users this user is following is empty.
Following: 0 users

Feed

Journal article
Published: 12 February 2021 in Geoderma
Reads 0
Downloads 0

Structure liming aims to improve soil structure (i.e., the spatial arrangement of particles and pores) and its stability against external and internal forces. Effects of lime application on soil structure have received considerable interest, but only a few studies have investigated effects on macro- and mesopore networks. We used X-ray computed tomography to image macropore networks (ø ≥ 0.3 mm) in soil columns and mesopores (ø ≥ 0.01 mm) in soil aggregates from three field sites with (silty) clay soils after the application of structure lime (3.1 t ha−1 or 5 t ha−1 of CaO equivalent). Segmented X-ray images were used to quantify soil porosity and pore size distributions as well as to analyse pore architecture and connectivity metrics. In addition, we investigated the amount of readily dispersible soil particles. Our results demonstrate that structure liming affected both, macropore networks and amounts of readily dispersible soil to different degrees, depending on the field site. Significant changes in macropore networks and amounts of readily dispersible soil after lime application were found for one of the three field sites, while only some indications for similar changes were observed at the other two sites. Overall, structure liming tended to decrease soil macroporosity and shift pore size distribution from larger (ε>1.0 mm) and medium sized macropores (ε0.3–1.0 mm) towards smaller macropores (ε0.1–0.3 mm). Furthermore, liming tended to decrease the critical and average pore diameters, while increasing the surface fractal dimension and specific surface area of macropore network. Structure liming also reduced the amounts of readily dispersible soil particles. We did not find any changes in mesopore network properties within soil aggregates or biopore networks in columns and aggregates. The effects of lime on macropore networks remain elusive, but may be caused by the formation of hydrate phases and carbonates which occupy pore space.

ACS Style

Tobias Bölscher; John Koestel; Ararso Etana; Barbro Ulén; Kerstin Berglund; Mats Larsbo. Changes in pore networks and readily dispersible soil following structure liming of clay soils. Geoderma 2021, 390, 114948 .

AMA Style

Tobias Bölscher, John Koestel, Ararso Etana, Barbro Ulén, Kerstin Berglund, Mats Larsbo. Changes in pore networks and readily dispersible soil following structure liming of clay soils. Geoderma. 2021; 390 ():114948.

Chicago/Turabian Style

Tobias Bölscher; John Koestel; Ararso Etana; Barbro Ulén; Kerstin Berglund; Mats Larsbo. 2021. "Changes in pore networks and readily dispersible soil following structure liming of clay soils." Geoderma 390, no. : 114948.

Preprint content
Published: 09 March 2020
Reads 0
Downloads 0

Protective mineral-organic associations are the quantitatively most important soil carbon storage mechanism, but their vulnerability to environmental change is largely uncertain. While it is well established that root growth can promote (or “prime”) the microbial decomposition of organic matter (OM), our mechanistic knowledge of the ability of roots to destabilize OM protected within mineral-organic associations remains limited. Here we examined how the composition of root-derived compounds (rhizodeposits) affects the stability of mineral-organic associations.

In model systems, we first tested the ability of functionally distinct low-molecular weight compounds (ligands, reductants, simple sugars) commonly observed in the rhizosphere to cause the mobilization and mineralization of isotopically labeled OM from different mineral types (Fe and Al hydroxides). Our results showed that all compounds stimulated mobilization and mineralization of previously mineral-associated OM. However, OM bound to Al hydroxide was less susceptible to mobilization than OM bound to Fe hydroxide. Further, sugars and reductants revealed a greater mobilization potential than ligands for both mineral types, suggesting that OM mobilization in soils may be microbially mediated, rather than driven by direct mineral dissolution. In complementary pot experiments, we investigated the effect of rhizodeposition on the mobilization of mineral-associated OM. We grew Avena sativa in soils amended with isotopically-labeled mineral-organic associations and followed mobilization dynamics over four weeks. First results indicated that rhizodeposition dynamics dictate the mobilization and mineralization of mineral-associated OM. Together, our results suggest a strong mechanistic linkage between the composition and functionality of rhizodeposits and their ability to destabilize mineral-associated OM.

ACS Style

Tobias Bölscher; Hui Li; Mariela Garcia Arredondo; Zoe G. Cardon; Carolyn M. Malmstrom; Matthew Winnick; Marco Keiluweit. Chemical complexity matters: differential mobilization of mineral-associated organic matter driven by functionally distinct rhizodeposits. 2020, 1 .

AMA Style

Tobias Bölscher, Hui Li, Mariela Garcia Arredondo, Zoe G. Cardon, Carolyn M. Malmstrom, Matthew Winnick, Marco Keiluweit. Chemical complexity matters: differential mobilization of mineral-associated organic matter driven by functionally distinct rhizodeposits. . 2020; ():1.

Chicago/Turabian Style

Tobias Bölscher; Hui Li; Mariela Garcia Arredondo; Zoe G. Cardon; Carolyn M. Malmstrom; Matthew Winnick; Marco Keiluweit. 2020. "Chemical complexity matters: differential mobilization of mineral-associated organic matter driven by functionally distinct rhizodeposits." , no. : 1.

Journal article
Published: 24 October 2019 in Soil Biology and Biochemistry
Reads 0
Downloads 0

Soil organic carbon (SOC) is a substantial source of atmospheric CO2, but also a large cause of uncertainties in Earth-system models. A principal control on soil CO2 release is the carbon-use efficiency (CUE) of microbial communities, which partitions the carbon (C) allocation between biosynthetic stabilization and CO2 respiration during SOC decomposition. In Earth-system models, CUE is commonly considered as a constant, although it should be susceptible to environmental factors such as temperature. We explored CUE across a set of land-uses and temperatures, and we show the hitherto neglected phenomenon that land-use can alter the temperature response of CUE. In arable soils, CUE was constant over a temperature range between 5 and 20 °C, but it decreased with temperature in ley farming, grassland, and forest soils at temperatures above 12.5 °C. The decrease in CUE was strongest for forest soils. Implementing our findings into a soil-C model revealed substantial differences in projected SOC losses: Assuming an increase of mean annual temperature of 2 or 4 °C, soils were projected to lose up to 6 or 15% of their current SOC, respectively, until they reach a new steady-state. These projections varied among land-uses. Our findings confront the current representation of CUE in global C models and challenges C sequestration strategies based on land-use changes, because land-uses such as e.g. forest ecosystems with current high C storage may lose substantially more C than agricultural soils due to strong declines of CUE.

ACS Style

Tobias Bölscher; Göran I. Ågren; Anke M. Herrmann. Land-use alters the temperature response of microbial carbon-use efficiency in soils – a consumption-based approach. Soil Biology and Biochemistry 2019, 140, 107639 .

AMA Style

Tobias Bölscher, Göran I. Ågren, Anke M. Herrmann. Land-use alters the temperature response of microbial carbon-use efficiency in soils – a consumption-based approach. Soil Biology and Biochemistry. 2019; 140 ():107639.

Chicago/Turabian Style

Tobias Bölscher; Göran I. Ågren; Anke M. Herrmann. 2019. "Land-use alters the temperature response of microbial carbon-use efficiency in soils – a consumption-based approach." Soil Biology and Biochemistry 140, no. : 107639.

Journal article
Published: 23 February 2016 in Biology and Fertility of Soils
Reads 0
Downloads 0

Microbial substrate use efficiency is an important property in process-based soil organic matter models, but is often assumed to be constant in mechanistic models. However, previous studies question if a constant efficiency is appropriate, in particular when evaluating carbon (C) cycling across temperatures and various substrates. In the present study, we evaluated the relation between substrate use efficiency, microbial community composition and substrate complexity in contrasting long-term management regimes (47–49 years of either arable, ley farming, grassland, or forest systems). Microbial community composition was assessed by phospholipid fatty acid analysis and three indices of substrate use efficiencies were considered: (i) thermodynamic efficiency, (ii) calorespirometric ratio, and (iii) metabolic quotient. Three substrates, d-glucose, l-alanine, or glycogen, varying in complexity, were added separately to soils, and heat production as well as C mineralization was determined over a 32-h incubation period at 12.5 °C. Microbial communities from forest systems were most efficient in utilizing substrates, supporting our hypothesis that maturing ecosystems become more efficient. These changes in efficiency were linked to microbial community composition with fungi and Gram-negative bacteria being important biomarkers. Despite our initial hypothesis, complex substrate such as glycogen was utilized most efficiently. Our findings emphasize that differences in land use management systems as well as the composition of soil organic matter need to be considered when modelling C dynamics in soils. Further research is required to establish and evaluate appropriate proxies for substrate use efficiencies in various ecosystems.

ACS Style

Tobias Bölscher; Lars Wadsö; Gunnar Börjesson; Anke Marianne Herrmann. Differences in substrate use efficiency: impacts of microbial community composition, land use management, and substrate complexity. Biology and Fertility of Soils 2016, 52, 547 -559.

AMA Style

Tobias Bölscher, Lars Wadsö, Gunnar Börjesson, Anke Marianne Herrmann. Differences in substrate use efficiency: impacts of microbial community composition, land use management, and substrate complexity. Biology and Fertility of Soils. 2016; 52 (4):547-559.

Chicago/Turabian Style

Tobias Bölscher; Lars Wadsö; Gunnar Börjesson; Anke Marianne Herrmann. 2016. "Differences in substrate use efficiency: impacts of microbial community composition, land use management, and substrate complexity." Biology and Fertility of Soils 52, no. 4: 547-559.

Journal article
Published: 11 September 2014 in Regional Environmental Change
Reads 0
Downloads 0

Climate studies show high likelihood of changing hydrological regimes in European rivers. Concerned authorities increasingly question the sustainability of current river management strategies. The aim of this paper is to apply the adaptation turning point (ATP) approach and demonstrates its potential for analysing turning points in river management strategies as a method to support authorities in decisions on adaptation to climate change. Two management strategies in the Rhine River basin were selected as case studies: (1) reintroduction of a sustainable population of Atlantic salmon and (2) inland shipping in relation to water depth variability. By applying the turning point approach, we search for answers to the following questions: when will these management strategies fail due to climate change impacts on the river’s hydrology? What adaptation measures exist to delay or avoid failure? The identification of adaption turning points is not easy, due to large scenario and model uncertainties in transient future projections of low-flow discharges and water temperatures. But the case studies demonstrate that the ATP approach is salient from a decision-maker’s perspective, because it addresses the timing of possible failure of current management strategies. Analysis of results allows policy makers to assess risks and the urgency for action and provides them with a time horizon for adaptation planning. It is also a valuable first step in the application of methods of formal appraisal of adaptation options when flexibility in planning is required.

ACS Style

Erik Van Slobbe; Saskia E. Werners; Marcela Riquelme-Solar; Tobias Bölscher; Michelle T. H. Van Vliet. The future of the Rhine: stranded ships and no more salmon? Regional Environmental Change 2014, 16, 31 -41.

AMA Style

Erik Van Slobbe, Saskia E. Werners, Marcela Riquelme-Solar, Tobias Bölscher, Michelle T. H. Van Vliet. The future of the Rhine: stranded ships and no more salmon? Regional Environmental Change. 2014; 16 (1):31-41.

Chicago/Turabian Style

Erik Van Slobbe; Saskia E. Werners; Marcela Riquelme-Solar; Tobias Bölscher; Michelle T. H. Van Vliet. 2014. "The future of the Rhine: stranded ships and no more salmon?" Regional Environmental Change 16, no. 1: 31-41.

Journal article
Published: 24 May 2013 in Sustainability
Reads 0
Downloads 0

Bringing a sustainable population of Atlantic salmon (Salmo salar) back into the Rhine, after the species became extinct in the 1950s, is an important environmental ambition with efforts made both by governments and civil society. Our analysis finds a significant risk of failure of salmon reintroduction because of projected increases in water temperatures in a changing climate. This suggests a need to rethink the current salmon reintroduction ambitions or to start developing adaptive action. The paper shows that the moment at which salmon reintroduction may fail due to climate change can only be approximated because of inherent uncertainties in the interaction between salmon and its environment. The added value of the assessment presented in this paper is that it provides researchers with a set of questions that are useful from a policy perspective (by focusing on the feasibility of a concrete policy ambition under climate change). Thus, it offers opportunities to supply policy makers with practical insight in the relevance of climate change.

ACS Style

Tobias Bölscher; Erik Van Slobbe; Michelle T.H. Van Vliet; Saskia E. Werners. Adaptation Turning Points in River Restoration? The Rhine Salmon Case. Sustainability 2013, 5, 2288 -2304.

AMA Style

Tobias Bölscher, Erik Van Slobbe, Michelle T.H. Van Vliet, Saskia E. Werners. Adaptation Turning Points in River Restoration? The Rhine Salmon Case. Sustainability. 2013; 5 (6):2288-2304.

Chicago/Turabian Style

Tobias Bölscher; Erik Van Slobbe; Michelle T.H. Van Vliet; Saskia E. Werners. 2013. "Adaptation Turning Points in River Restoration? The Rhine Salmon Case." Sustainability 5, no. 6: 2288-2304.