Point effluent discharges have unclear direct impacts on local biogeochemical P cycling against high background complexity in catchment pollution processes and ecosystem responses

2020 ◽  
Author(s):  
Marc Stutter ◽  
Samia Richards
Keyword(s):  
Spatial Data ◽  
Stream Water ◽  
Ex Situ ◽  
Stream Network ◽  
Ecosystem Responses ◽  
High Background ◽  
Ecosystem Effects ◽  
Multiple Stressor ◽  
Downstream Effects ◽  
Substrate Induced Respiration

<p>Point discharges of pollution such as effluents, enriched in bioavailable nutrients, organic matter and multiple contaminants, are often considered as having both strong local and cumulative downstream effects on aquatic ecosystem quality. Since potential impacts of effluents involve many multiple stressor interactions it requires an integrated suite of in-situ and ex-situ techniques to evaluate the biotic and abiotic interplay of the ecosystem effects. This study aimed to evaluate impacts using sampling transects around discharges from wastewater treatment works (WWTW) to a range of watercourses. The hypothesis was that major effluent discharges would lead to local downstream enrichment in nutrient and microbial contaminants, altered microbial communities and impairment in P processing rates with downstream recovery distances related to cumulative upstream pollution.</p><p>Five river transects were evaluated on two dates comprising points 100m above then 100, 200, 500 m below stream-side WWTW. Stream water samples were collected (effluents where possible) and analysed for C, N, P forms, coliforms, pesticides and pharmaceuticals. Biofilms (grown on tiles between sampling dates) and recovered for analysis alongside bed sediments for stoichiometry, P enzyme activity, substrate induced respiration assays and chlorophyll (biofilms). Catchments were characterised using spatial data on landcover, stream network and cumulative pollution sources.</p><p>Patterns of pollution presence in the waters and cycling indicators in the bed and periphyton did not show clear patterns of high local and declining downstream impacts. Instead a surprising complexity of weak transect effects amongst a high background heterogeneity was seen. This likely results from a heterogeneous biophysical environment of the channel as well as the complexity of the catchment ‘diffuse’ pollution inputs. Hence, WWTW impacts on aquatic pollution presence and processing factors were unclear and masked by catchment system heterogeneity and complexity.   </p>

scholarly journals A Geospatial Thinking Multiyear Study

2020 ◽  
Vol 12 (11) ◽  
pp. 4586
Author(s):  
Carlos Carbonell-Carrera ◽  
Jose Luis Saorin ◽  
Stephany Hess-Medler
Keyword(s):  
Academic Success ◽  
Water Flow ◽  
Spatial Data ◽  
Environmental Sustainability ◽  
Engineering Students ◽  
Stream Water ◽  
Landscape Management ◽  
Data Infrastructure ◽  
Agricultural Engineering ◽  
Geospatial Thinking

In the field of environmental sustainability and landscape management, geospatial thinking is necessary. A good level of geospatial thinking is related to academic success in engineering degrees. It is relevant, therefore, to detect the possible deficiencies that university students may have in tasks related to geospatial thinking. This research presents the results of a 2014‒2019 multiyear study with agricultural engineering students, in which seven geospatial tasks were analyzed. The statistical analysis shows that geospatial tasks related to slope, stream/water flow, visibility, and relief interpretation are the best at predicting the final course mark. The present research provides quantitative data on the efficiency that four technologies have to reinforce geospatial thinking focused on each task. Augmented Reality is an appropriate 3D technology for geospatial tasks related to route search, stream/water flow, and elevation points. SketchUp Make 2017 and Autodesk 123D Make showed their potential to solve tasks related to terrain slope and visibility analysis. Spatial Data Infrastructure has given the best results in geospatial tasks related to the photointerpretation of the relief and with topographic profiles of the terrain. Our findings will help teachers to select the most appropriate geospatial tasks to include in their courses.

Landscape variations in stream water SO42− and δ34SSO4 in a boreal stream network

2009 ◽  
Vol 73 (16) ◽  
pp. 4648-4660 ◽  
Author(s):  
Louise Björkvald ◽  
Reiner Giesler ◽  
Hjalmar Laudon ◽  
Christoph Humborg ◽  
Carl-Magnus Mörth
Keyword(s):  
Stream Water ◽  
Stream Network

scholarly journals Particle-by-Particle in Situ Characterization of the Protein Corona via Real-Time 3D Single Particle Tracking Microscopy

2021 ◽  
Author(s):  
Xiaochen Tan ◽  
Kevin Welsher
Keyword(s):  
Real Time ◽  
Particle Tracking ◽  
Single Particle ◽  
Biological Fluids ◽  
Protein Corona ◽  
Single Particle Tracking ◽  
Ex Situ ◽  
High Background ◽  
Particle Nature

<p>Nanoparticles (NPs) adsorb proteins when exposed to biological fluids, forming a dynamic protein corona that affects their fate in biological environments. A comprehensive understanding of the protein corona is lacking due to the inability of current techniques to precisely measure the full corona <i>in situ</i> at the single particle level. Herein, we introduce a 3D real-time single-particle tracking spectroscopy to "lock-on" to single freely-diffusing polystyrene NPs and probe their individual protein coronas. The diffusive motions of the tracked NPs enable quantification of the "hard corona" using mean-squared displacement analysis. Critically, this method's particle-by-particle nature enabled a lock-in-type frequency filtering approach to extract the full protein corona, despite the typically confounding effect of high background signal from unbound proteins. From these results, the dynamic <i>in situ </i>full protein corona is observed to contain double the number of proteins than are observed in the <i>ex situ</i> measured "hard" protein corona.</p><br>

Linking the dynamic expansion and contraction of stream networks to changes in water storage and water quality in a pre-Alpine catchment

2021 ◽  
Author(s):  
Izabela Bujak ◽  
Andrea Rinaldo ◽  
Ilja van Meerveld ◽  
Florian Käslin ◽  
Jana von Freyberg
Keyword(s):  
Water Quality ◽  
Stream Water ◽  
Network Dynamics ◽  
Water Storage ◽  
Stream Water Quality ◽  
Stream Network ◽  
Rainfall Events ◽  
Headwater Catchments ◽  
Research Activities ◽  
Flowing Stream

&lt;p&gt;Many headwater catchments are characterized by temporary streams that flow only seasonally or during rainfall events. As a result, the network of flowing streams is a dynamic system that periodically expands and contracts. This dynamic is likely to affect water flow and composition: the expansion of the stream network enhances the hydrologic connectivity of hillslopes to the streams, which facilitates shorter transit times. Also, the onset of flow in previously dry streambeds can cause flushing of sediments and nutrients. However, our knowledge of the relationships between flowing stream network dynamics and water quantity and quality in headwater catchments is still limited because experimental data remain sparse.&lt;/p&gt;&lt;p&gt;Within the TempAqua project we investigate the processes that drive stream network dynamics by relating measurements of stream network geometry to changes in catchment water storage and stream water quality. For this, we monitored the flow state, discharge, groundwater levels, soil moisture, and precipitation in three (3-7 ha) headwater catchments in the northern Swiss pre-Alps (Alptal catchment) in summer and fall 2020 using a wireless sensor network. To obtain high-resolution data of the dynamic stream network, we did multiple mapping surveys using a self-developed mobile phone application. Moreover, we sampled streamwater and precipitation at an hourly resolution during rainfall events at multiple locations to quantify the short-term changes in water quality when the stream network expands. We will present our research activities in the Alptal catchment and discuss the initial results obtained from the combined monitoring of the flowing stream network and hydrometric and hydrochemical variables.&lt;/p&gt;

scholarly journals Sorbitol-fermenting Bifidobacteria are indicators of very recent human faecal pollution in streams and groundwater habitats in urban tropical lowlands

2010 ◽  
Vol 8 (3) ◽  
pp. 466-478 ◽  
Author(s):  
Douglas Mushi ◽  
Denis Byamukama ◽  
Amelia K. Kivaisi ◽  
Robert L. Mach ◽  
Andreas H. Farnleitner
Keyword(s):  
Stream Water ◽  
Evaluation Studies ◽  
Water Quality Monitoring ◽  
High Background ◽  
Human Faeces ◽  
E Coli ◽  
Faecal Pollution ◽  
Tropical Water ◽  
Microcosm Studies ◽  
Tropical Lowlands

Sorbitol-fermenting Bifidobacteria (SFB) proved to be an excellent indicator of very recent human faecal pollution (hours to days) in the investigated tropical stream and groundwater habitats. SFB were recovered from human faeces and sources potentially contaminated with human excreta. SFB were undetectable in animal faeces and environmental samples not contaminated with human faeces. Microcosm studies demonstrated a rapid die-off rate in groundwater (T90 value 0.6 days) and stream water (T90 value 0.9–1.7 days). Discrimination sensitivity analysis, including E. coli, faecal coliforms, total coliforms and Clostridium perfringens spores, revealed high ability of SFB to distinguish differing levels of faecal pollution especially for streams although high background levels of interfering bacteria can complicate its recovery on the used medium. Due to its faster die-off, as compared to many waterborne pathogens, SFB cannot replace microbiological standard parameters for routine water quality monitoring but it is highly recommendable as a specific and complementary tool when human faecal pollution has to be localized or verified. Because of its exclusive faecal origin and human specificity it seems also worthwhile to include SFB in future risk evaluation studies at tropical water resources in order to evaluate under which situations risks of infection may be indicated.

scholarly journals GIS-Based Site Selection for Check Dams in Watersheds: Considering Geomorphometric and Topo-Hydrological Factors

2019 ◽  
Vol 11 (20) ◽  
pp. 5639 ◽  
Author(s):  
Omid Rahmati ◽  
Zahra Kalantari ◽  
Mahmood Samadi ◽  
Evelyn Uuemaai ◽  
Davoud Davoudi Moghaddam ◽  
...  
Keyword(s):  
Sediment Transport ◽  
Spatial Data ◽  
Site Selection ◽  
Drainage Density ◽  
Stream Power ◽  
Topographic Wetness Index ◽  
Stream Network ◽  
Flood Peak ◽  
Check Dams ◽  
The World

Check dams are widely used watershed management measures for reducing flood peak discharge and sediment transport, and increasing lag time and groundwater recharge throughout the world. However, identifying the best suitable sites for check dams within the stream networks of various watersheds remains challenging. This study aimed to develop an open-source software with user-friendly interface for screening the stream network possibilities and identifying and guiding the selection of suitable sites for check dams within watersheds. In this developed site selection software (SSS), multi-criteria decision analysis (MCDA) was integrated into geographic information systems (GIS), which allowed for numerous spatial data of the multiple criteria to be relatively simply and visually processed. Different geomorphometric and topo-hydrological factors were considered and accounted for to enhance the SSS identification of the best locations for check dams. The factors included topographic wetness index (TWI), terrain ruggedness index (TRI), topographic position index (TPI), sediment transport index (STI), stream power index (SPI), slope, drainage density (DD), and stream order (SO). The site identification performance of the SSS was assessed using the receiver operating characteristic (ROC) curve method, with results for the case study example of the Poldokhtar watershed in Iran showing excellent performance and identifying 327 potential sites for efficient check dam construction in this watershed. The SSS tool is not site-specific but is rather general, adaptive, and comprehensive, such that it can and should be further applied and tested across different watersheds and parts of the world.

scholarly journals Multiple-Stressor Interactions in Tributaries Alter Downstream Ecosystems in Stream Mesocosm Networks

Water ◽  
2021 ◽  
Vol 13 (9) ◽  
pp. 1194
Author(s):  
Ana M. Chará-Serna ◽  
John S. Richardson
Keyword(s):  
Population Dynamics ◽  
Second Order ◽  
Physical Habitat ◽  
Stream Networks ◽  
Stream Network ◽  
Dispersal Patterns ◽  
Multiple Stressor ◽  
Ept Taxa ◽  
Stream Mesocosm ◽  
Ept Richness

We studied how multiple-stresssors in tributaries affect function, diversity, and physical habitat of recipient downstream ecosystems. Using a mesocosm model of a stream network, we manipulated sediment and nutrients individually and in combination in tributaries of second-order channels, to test the effect of complex stressor interactions within tributaries on recipient channels. Sedimentation in second-order channels increased with the level of disturbance of the tributaries. Moreover, Ephemeroptera, Plecoptera, and Trichoptera (EPT) density and EPT richness were higher in second-order channels fed by tributaries where the stressors were applied separately, compared to those fed by tributaries where the stressors were applied simultaneously. Our observations suggest this result was due to the combination of the two stressors within the same tributary reducing EPT drift from the tributaries further than the addition of the stressors in separate tributaries. These results support the hypothesis that cumulative upstream disturbance can influence downstream recipient ecosystems in stream networks. However, contrary to our expectations, most observed effects were due to impacts on dispersal patterns of EPT taxa, rather than downstream accumulation of disturbances throughout the network. Our results underscore the importance of metacommunity frameworks to understand how tributary disturbance may influence population dynamics in downstream ecosystems.

scholarly journals INSPIRE standards as framework for artificial intelligence applications: a landslides example

2020 ◽  
Author(s):  
Gioachino Roberti ◽  
Jacob McGregor ◽  
Sharon Lam ◽  
David Bigelow ◽  
Blake Boyko ◽  
...  
Keyword(s):  
Artificial Intelligence ◽  
European Union ◽  
Spatial Data ◽  
Landslide Susceptibility ◽  
Semantic Networks ◽  
Scientific Models ◽  
Susceptibility Map ◽  
The European Union ◽  
Stream Network ◽  
Data Infrastructure

Abstract. This study presents a landslide susceptibility map using an artificial intelligence (AI) approach that is based on standards set by the INSPIRE framework. We show how INSPIRE standards enhance the interoperability of geospatial data, and enable deeper knowledge development for their interpretation and explainability in AI applications. INSPIRE is a European Union Spatial Data Infrastructure (SDI) initiative to standardize spatial data across borders to ensure interoperability for management of cross-border infrastructure and environmental issues. Despite the theoretical effectiveness of the SDI, very few real-world applications make use of INSPIRE standards. We designed an ontology of landslides, embedded with INSPIRE vocabularies and then aligned geology, stream network and land cover data sets covering the Veneto region of Italy to the standards. INSPIRE was formally extended to include an extensive landslide type code list, a landslide size code list and the concept of landslide susceptibility to describe map application inputs and outputs. Using the terms in the ontology, we defined conceptual scientific models of slopes likely to generate landslides as well as map polygons representing real slopes. Both landslide models and map polygons were encoded as semantic networks and, by qualitative probabilistic comparison between the two, a similarity score was assigned. The score was then used as a proxy for landslide susceptibility and displayed in web map application. The use of INSPIRE-standardized vocabularies in ontologies that express scientific models promotes the adoption of the standards across the European Union and beyond. Further, this application facilitates the explainability of the generated results. We conclude that public and private organisations, within and outside the European Union, can enhance the value of their data by bringing them into INSPIRE-compliance for use in AI applications.

scholarly journals Particle-by-Particle in Situ Characterization of the Protein Corona via Real-Time 3D Single Particle Tracking Microscopy

2021 ◽  
Author(s):  
Xiaochen Tan ◽  
Kevin Welsher
Keyword(s):  
Real Time ◽  
Particle Tracking ◽  
Single Particle ◽  
Biological Fluids ◽  
Protein Corona ◽  
Single Particle Tracking ◽  
Ex Situ ◽  
High Background ◽  
Particle Nature

<p>Nanoparticles (NPs) adsorb proteins when exposed to biological fluids, forming a dynamic protein corona that affects their fate in biological environments. A comprehensive understanding of the protein corona is lacking due to the inability of current techniques to precisely measure the full corona <i>in situ</i> at the single particle level. Herein, we introduce a 3D real-time single-particle tracking spectroscopy to "lock-on" to single freely-diffusing polystyrene NPs and probe their individual protein coronas. The diffusive motions of the tracked NPs enable quantification of the "hard corona" using mean-squared displacement analysis. Critically, this method's particle-by-particle nature enabled a lock-in-type frequency filtering approach to extract the full protein corona, despite the typically confounding effect of high background signal from unbound proteins. From these results, the dynamic <i>in situ </i>full protein corona is observed to contain double the number of proteins than are observed in the <i>ex situ</i> measured "hard" protein corona.</p><br>

Sign in / Sign up

Export Citation Format

Share Document