Kevin Bishop

Kevin Bishop
Swedish University of Agricultural Sciences | SLU · Department of Aquatic Sciences and Assessment

About

324
Publications
68,250
Reads
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15,368
Citations
Citations since 2016
66 Research Items
8055 Citations
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201620172018201920202021202202004006008001,0001,200
201620172018201920202021202202004006008001,0001,200
201620172018201920202021202202004006008001,0001,200

Publications

Publications (324)
Article
Full-text available
Air‐sea exchange of gaseous elemental mercury (Hg⁰) is not well constrained, even though it is a major component of the global Hg cycle. Lack of Hg⁰ flux measurements to validate parameterizations of the Hg⁰ transfer velocity contributes to this uncertainty. We measured the Hg⁰ flux on the Baltic Sea coast using micrometeorological methods (gradien...
Chapter
This chapter reviews how global change affects forest-water interactions and water availability to ecosystems and people and synthesises current understanding of the implications of present and anticipated changes to forests and tree cover for local and global hydrology. Forest cover has declined in the past half-century, despite an increase in pla...
Article
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The rapid development of novel technologies to obtain high‐frequency observations has provided new possibilities to observe and understand carbon cycling in inland waters. This study investigates carbon dioxide (CO2) dynamics along a boreal soil‐stream transect using a state‐of‐the‐art dataset in combination with a spectral methodology to identify...
Article
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Human water use, climate change and land conversion have created a water crisis for billions of individuals and many ecosystems worldwide. Global water stocks and fluxes are estimated empirically and with computer models, but this information is conveyed to policymakers and researchers through water cycle diagrams. Here we compiled a synthesis of t...
Article
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Stream CO2 emissions contribute significantly to atmospheric climate forcing. While there are strong indications that groundwater inputs sustain these emissions, the specific biogeochemical pathways and timescales involved in this lateral CO2 export are still obscure. Here, via an extensive radiocarbon (¹⁴C) characterisation of CO2 and DOC in strea...
Article
Streamflow recession analysis provides valuable insights into catchment functioning that can be related to runoff generation, storage retention and baseflow dynamics. As an integrated characteristic, recession analysis is particularly useful in catchment comparison studies to help explain drivers of spatial and temporal variability in hydrological...
Article
Soil compaction is a common consequence of forestry traffic traversing unprotected, moist soils; it decreases porosity and affects hydraulic conductivity even in coarse-textured soils. The aim here was to study root-zone hydrology and vegetation in three microsites – in, between, and beside wheel tracks – 4-5 years after forwarder traffic, on stony...
Article
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This focus article presents the state of the West African rainforest (WARF), its role in atmospheric moisture transport to the Nile Basin, and the potential impact of its deforestation on the Nile Basin's water regime, as well as options for improving transboundary water governance. The Nile is the longest river in the world, but delivers less wate...
Article
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Managed forests can play an important role in climate change mitigation due to their capacity to sequester carbon. However, it has proven difficult to harness their full potential for climate change mitigation. Managed forests are often referred to as socio-ecological systems as the human dimension is an integral part of the system. When attempting...
Article
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A number of studies have evaluated the effects of forest harvest on mercury (Hg) concentrations and exports in surface waters, but few studies have tested the effect from forest harvest on the change in fish Hg concentrations over the course of several years after harvest. To address this question, mercury (Hg) concentrations in perch (Perca fluvia...
Article
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The boreal ecoregion supports about one-third of the world’s forest. Over 90% of boreal forest streams are found in headwaters, where terrestrial–aquatic interfaces are dominated by organic matter (OM)-rich riparian zones (RZs). Because these transition zones are key features controlling catchment biogeochemistry, appropriate RZ conceptualizations...
Article
In this paper we explored how landscape characteristics such as topography, geology, soils and land cover influence the way catchments respond to changing climate conditions. Based on an ensemble of 15 regional climate models bias-corrected with a distribution-mapping approach, present and future streamflow in 14 neighboring and rather similar catc...
Article
Full-text available
Purpose Much attention is directed to the accumulation of mercury and methylmercury (MeHg) in rice grown on Hg-contaminated paddy fields, since they pose a risk to the health of both people and wildlife. Ultimately, measures to control the accumulation of Hg and MeHg in rice should become a key focus of research on this topic. The objective of this...
Article
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Low-order streams are suggested to dominate the atmospheric CO2 source of all inland waters. Yet, many large-scale stream estimates suffer from methods not designed for gas emission determination and rarely include other greenhouse gases such as CH4. Here we present a compilation of directly measured CO2 and CH4 concentration data from Swedish low-...
Article
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Considerable CO2 evasion to the atmosphere occurs as DIC is transported from soils to streams. While this physical process has been the focus of multiple studies, less is known about the underlying biogeochemical transformations that accompany this transfer of C from soils to streams. Here, we used patterns in streamwater and groundwater δ13C-DIC v...
Article
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It is well established that stream dissolved inorganic carbon (DIC) fluxes play a central role in the global C cycle, yet the sources of stream DIC remain to a large extent unresolved. Here, we explore large-scale patterns in δ¹³C-DIC from streams across Sweden to separate and further quantify the sources and sinks of stream DIC. We found that stre...
Article
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Peatlands are a major source of methylmercury that contaminates downstream aquatic food webs. The large store of mercury (Hg) in peatlands could be a source of Hg for over a century even if deposition is dramatically reduced. However, the reliability of Hg mass balances can be questioned due to missing long-term land-atmosphere flux measurements. W...
Article
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Neurotoxic methylmercury causes adverse effects to ecosystem viability and human health. Previous studies have revealed that ponding alters natural organic matter (NOM) composition and increase methylmercury concentrations in rivers, especially in the first years after flooding. Here, we investigate the influence of NOM composition (i.e., sources a...
Article
The dramatic increase of bioreactive nitrogen entering Earth's ecosystems continues to attract growing attention. Increasingly large quantities of inorganic nitrogen are flushed from land to water, accelerating freshwater and marine eutrophication. Multiple, interacting, and potentially countervailing drivers control the future hydrologic export of...
Article
Full-text available
Quantitative estimates of the land-atmosphere exchange of gaseous elemental mercury (GEM) are biased by the measurement technique employed, because no standard method or scale in space and time are agreed upon. Here we present concurrent GEM exchange measurements over a boreal peatland using a novel relaxed eddy accumulation (REA) system, a rectang...
Article
Mercury (Hg) is a globally-distributed pollutant, toxic to humans and animals. Emissions are particularly high in Asia, and the source of exposure for humans there may also be different from other regions, including rice as well as fish consumption, particularly in contaminated areas. Yet the threats Asian wildlife face in rice-based ecosystems are...
Article
Earlier studies have shown that boreal forest logging can increase the concentration and export of methylmercury (MeHg) in stream runoff. Here we test whether forestry operations create soil environments of high MeHg net formation associated with distinct microbial communities. Furthermore, we test the hypothesis that Hg methylation hotspots are mo...
Article
Soil moisture is an important variable for hillslope and catchment hydrology. There are various computational methods to estimate soil moisture and their complexity varies greatly: from one box with vertically constant volumetric soil water content to fully saturated-unsaturated coupled physically-based models. Different complexity levels are appli...
Article
A better understanding of the dominant source areas and transport pathways of pesticide losses to surface water is needed for targeting mitigation efforts in a more cost-effective way. To this end, we monitored pesticides in surface water in an agricultural catchment typical of one of the main crop production regions in Sweden. Three small sub-catc...
Article
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The stability of northern peatland's carbon (C) store under changing climate is of major concern for the global C cycle. The aquatic export of C from boreal peatlands is recognized as both a critical pathway for the remobilization of peat C stocks as well as a major component of the net ecosystem C balance (NECB). Here, we present a full year chara...
Article
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Beaver impoundments modify the structure of river reaches and lead to changes in ecosystem function and biogeochemical processes. Here, we assessed the changes in dissolved organic matter (DOM) quality and the biodegradation patterns in a set of beaver systems across Sweden. As the effect of beaver impoundments might be transient and local, we comp...
Article
This study assessed variations in the concentrations of poly- and perfluoroalkyl substances (PFAS) in European perch (Perca fluviatilis) in Swedish lakes and the extent to which fish size, age and indicators of fish trophic ecology (δ(15)N and δ(13)C) correlate with the sum of individual PFAS concentrations (ΣPFAS). Fish muscle tissue samples (n=80...
Article
Basin infiltration managed aquifer recharge (MAR) is a commonly used method for storing and treating surface water to be used as drinking water. This study examined how the removal of bacteriophage MS2 was affected by the relative age of the sand used for basin infiltration MAR at 4 °C using batch experiments (static and agitated) and column experi...
Conference Paper
The distribution of groundwater residence time in a catchment provides synoptic information about catchment functioning (e.g. nutrient retention and removal, hydrograph flashiness). In contrast with interpreted model results, which are often not directly comparable between studies, residence time distribution is a general output that could be used...
Article
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This study examined how the inactivation of bacteriophage MS2 in water was affected by ionic strength (IS) and dissolved organic carbon (DOC) using static batch inactivation experiments at 4 °C conducted over a period of 2 months. Experimental conditions were characteristic of an operational managed aquifer recharge (MAR) scheme in Uppsala, Sweden....
Article
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A survey carried out in Lake Tana in 2015 found that Hg levels in some fish species exceeded internationally accepted safe levels for fish consumption. The current study assesses human exposure to Hg through fish consumption around the Lake Tana. Of particular interest was that a dietary intake of fishes is currently a health risk for Bihar Dar res...
Article
Excess nitrogen fertiliser in agricultural soils might be leached to streams and converted to the greenhouse gas nitrous oxide (N2O). To assess the importance of N2O emissions from agricultural streams, concentration dynamics and emissions N2O emissions in streams were investigated in a 32 km² lowland agricultural catchment located in Sweden. Disso...
Article
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The permeability architecture of the critical zone exerts a major influence on the hydrogeochemistry of the critical zone. Water flow path dynamics drive the spatiotemporal pattern of geochemical evolution and resulting streamflow concentration-discharge (C-Q) relation, but these flow paths are complex and difficult to map quantitatively. Here we c...
Article
Studies on hydrology, biogeochemistry or mineral weathering often rely on assumptions about flow paths, water storage dynamics and transit times. Testing these assumptions requires detailed hydrometric data which are usually unavailable at the catchment scale. Hillslope studies provide an alternative for obtaining a better understanding, but even o...
Article
Mercury (Hg), deposited from emissions or from local contamination, can have serious health effects for humans and wildlife. Traditionally, Hg has been seen as a threat to aquatic wildlife, because of its conversion in suboxic conditions into bioavailable methylmercury (MeHg), but it can also threaten contaminated terrestrial ecosystems. In Asia, r...
Article
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To achieve a safe and reliable drinking water supply, water producers need to manage a large range of risks regarding both water quality and quantity. A risk management approach where risks are systematically identified and handled in a preventive manner is promoted by the World Health Organization and supported by researchers and drinking water ex...
Article
Residue biomass from conventional forestry, such as slash (i.e., tree tops and branches) and stumps, are used at an increasing rate for energy purposes in Sweden. This review examined current knowledge on how extraction of forest biomass for large-scale energy production, including the practice of ash application for nutrient recycling, influences...
Article
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Improving the understanding of how stream flow dynamics are influenced by landscape characteristics, such as soils, vegetation and terrain, is a central endeavor of catchment hydrology. Here we investigate how spatial variability in stream flow is related to landscape characteristics using specific discharge time series from 14 partly nested sub-ca...
Article
Risk assessments are important to ensure efficient and effective flood risk management. Methods and strategies for flood risk assessment are described in the literature, but less is known about how assessments are actually performed. We have studied local flood risk assessments in Sweden by interviewing flood risk managers in municipalities and ana...
Article
Predicting hydrological catchment behaviour based on measurable (and preferably widely available) catchment characteristics has been one of the main goals of hydrological modelling. Residence time distributions provide synoptic information about catchment functioning and can be useful metrics to predict their behaviours. Moreover, residence time di...
Article
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Defining the catchment transit time distribution remains a challenge. Here, we used a new semi-analytical physically-based integrated subsurface flow and advective-dispersive particle movement model to assess the subsurface controls on subsurface water flow paths and transit time distributions. First, we tested the efficacy of the new model for sim...
Article
Nearby catchments in the same landscape are often assumed to have similar specific discharge (runoff per unit catchment area). Five years of streamflow from 14 nested catchments in a 68km2 landscape was used to test this assumption, with the hypothesis that the spatial variability in specific discharge is smaller than the uncertainties in the measu...
Article
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The study presents a hydrology concept developed to include lateral water flow in the biogeochemical model ForSAFE. The hydrology concept was evaluated against data collected at Svartberget in the Vindeln Research Forest in Northern Sweden. The results show that the new concept allows simulation of a saturated and an unsaturated zone in the soil as...
Article
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As the permafrost region warms, its large organic carbon pool will be increasingly vulnerable to decomposition, combustion, and hydrologic export. Models predict that some portion of this release will be offset by increased production of Arctic and boreal biomass; however, the lack of robust estimates of net carbon balance increases the risk of fur...
Article
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The fate of anthropogenic emissions of mercury (Hg) to the atmosphere is influenced by the exchange of elemental Hg with the earth surface. This exchange holds the key to a better understanding of Hg cycling from local to global scales, which has been difficult to quantify. To advance research about land–atmosphere Hg interactions, we developed a d...
Article
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Inputs of anthropogenic mercury (Hg) to the environment have led to accumulation of Hg in terrestrial and aquatic ecosystems, contributing to fish Hg concentrations well above the European Union standards in large parts of Fennoscandia. Forestry operations have been reported to increase the concentrations and loads of Hg to surface waters by mobili...
Article
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Protecting water quality in forested regions is increasingly important as pressures from land-use, long-range transport of air pollutants, and climate change intensify. Maintaining forest industry without jeopardizing sustainability of surface water quality therefore requires new tools and approaches. Here, we show how forest management can be opti...
Article
Full-text available
In spite of the great abundance and ecological importance of headwater streams, managers are usually limited by a lack of information about water chemistry in these headwaters. In this study we test whether river outlet chemistry can be used as an additional source of information to improve the prediction of the chemistry of upstream headwaters (si...
Article
Full-text available
Dissolved organic carbon (DOC) is a significant constituent in aquatic ecosystems with concentrations in streams influenced by both temperature and water flow pathway dynamics associated with changes in discharge (streamflow). We investigated the sensitivity of DOC concentrations in 12 high-latitude headwater streams to changes in temperature and d...
Article
Full-text available
The strong vertical gradient in soil and subsoil saturated hydraulic conductivity is characteristic feature of the hydrology of catchments. Despite the potential importance of these strong gradients, they have proven difficult to model using robust physically based schemes. This has hampered the testing of hypotheses about the implications of such...
Article
In this paper we combined a multimodel ensemble based on 15 regional climate models with a multicatchment approach to explore the hydrologic sensitivity of 14 neighboring and rather similar catchments to changing climate conditions. Current (1982-2010) and future (2062-2090) streamflow was simulated with the HBV model. A diagnostic approach was use...