Effects of wetland conversion into farming on water quality, sediment and nutrient retention - synthesis, conclusions and recommendations

The largest blue-green infrastructures in industrialized, urbanized and developed regions in China are often multiuse wetlands, located just outside growing urban centers. These areas have multiple development pressures while providing environmental, economic, and social benefits to the local and regional populations. Given the limited information available about the tradeoffs in ecosystem services with respect to competing wetland uses, wetland managers and provincial decision makers face challenges in regulating the use of these important landscapes. In the present study, measurements made by citizen scientists were used to support a comparative study of water quality and wetland functions in two large multiuse wetlands, comparing areas of natural wetland vegetation, tourism-based wetland management and wetland agriculture. The study sites, the Nansha and Tianfu wetlands, are located in two of the most urbanized areas of China: the lower Yangtze River and Pearl River catchments, respectively. Our results indicated that the capacity of wetlands to mitigate water quality is closely related to the quality of the surrounding waters and hydrological conditions. Agricultural areas in both wetlands provided the lowest sediment and nutrient retention. The results show that the delivery of supporting ecosystem services is strongly influenced by the location and use of the wetland. Furthermore, we show that citizen scientist-acquired data can provide fundamental information on quantifying these ecosystem services, providing needed information to wetland park managers and provincial wetland administrators.

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Nutrient Limitation and Uptake Rates in Streams and Rivers of the Greater Yellowstone Ecosystem

The UW National Parks Service Research Station Annual Reports ◽

10.13001/uwnpsrc.2013.4011 ◽

2013 ◽

Vol 36 ◽

pp. 153-159

Author(s):

Jennifer Tank ◽

Alexander Reisinger

Keyword(s):

Water Quality ◽

Nutrient Limitation ◽

Water Column ◽

Nutrient Dynamics ◽

Nutrient Retention ◽

Light Limitation ◽

Small Stream ◽

Streams And Rivers ◽

Greater Yellowstone ◽

Uptake Studies

Nutrient pollution of aquatic ecosystems is a growing concern as the influence of human activities continues to increase on the landscape. Headwater streams have long been shown to process nutrients via the biofilm community growing on the bottom of streams. The growth and activity of these biofilms is often limited by the availability of nitrogen (N), phosphorus (P), or co-limited by both N and P. Although small stream nutrient dynamics are relatively well understood, comparatively little is known about larger, non-wadeable rivers. Biofilms on the river bottom are likely still nutrient limited, but there becomes an increased potential for light limitation as rivers increase in depth. In addition to biofilms on the bottom of rivers, free-living microbial communities suspended in the water column also occur in rivers and process nutrients - a component of nutrient processing largely ignored in streams. In summer 2013 we worked in streams and rivers of the Greater Yellowstone Area (GYA) to establish the nutrient limitation status of minimally-impacted rivers, as well as the role of the water column in processing nutrients as streams increase in size. For both the nutrient limitation and water column uptake studies, we are using the GYA sites in addition to systems from other regions of the US to establish what controls the various aspects of nutrient dynamics in rivers. Our results from the GYA, in addition to Midwest and Southwest US rivers, will provide water quality managers with new strategies for improving water quality downstream, and clarify mechanisms controlling nutrient retention in rivers.

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Observations of carbon-nitrogen manipulation and periphyton growth stimulation on fish farming in an integrated intensive-extensive aquaculture system

Fisheries & Aquatic Life ◽

10.2478/aopf-2019-0019 ◽

2019 ◽

Vol 27 (4) ◽

pp. 169-177

Author(s):

Ludmiła Kolek ◽

Maciej Pilarczyk ◽

Michał Inglot ◽

Bartłomiej Stonawski ◽

Joanna Szczygieł

Keyword(s):

Water Quality ◽

Silver Carp ◽

Nutrient Retention ◽

Fish Farming ◽

Growth Stimulation ◽

Nutrient Utilization ◽

Fish Production ◽

Hypophthalmichthys Molitrix ◽

Chondrostoma Nasus ◽

Fish Tanks

Abstract The results of observations of intensive sturgeon production integrated with an extensive earthen fish pond are described. The main objective of the study was to show how technological modifications applied to enhance nitrogen assimilation in ponds and nutrient retention in aquaculture products influenced fish production. Each of two integrated systems, A and B, consisted of four intensive fish tanks stocked with sturgeon and one extensive carp pond stocked with carp (Cyprinus carpio L.), silver carp (Hypophthalmichthys molitrix (Val.)) and common nase (Chondrostoma nasus L.). The fish tanks were supplied with water from the extensive pond and the effluent from the tanks was discharged into the same pond, which acted as a biological filter for fish production. System B pond was supplemented with carbohydrates (methanol) and plastic substrates for periphyton development that were installed to increase nutrient utilization. The results of the observations showed better water quality and higher fish production in pond B, but no differences were noted in sturgeon growth performance in system A. The combination of these modifications appeared to be an efficient way of increasing nutrient retention and improving water quality.

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Managing the small stream network for improved water quality, biodiversity and ecosystem services protection (SSNet)

Research Ideas and Outcomes ◽

10.3897/rio.5.e33400 ◽

2019 ◽

Vol 5 ◽

Author(s):

Mary Kelly-Quinn ◽

Michael Bruen ◽

Jens Carlsson ◽

Angela Gurnell ◽

Helen Jarvie ◽

...

Keyword(s):

Water Quality ◽

Ecosystem Services ◽

Environmental Protection Agency ◽

Nutrient Retention ◽

Integrated Approach ◽

Stream Network ◽

Management Options ◽

Small Stream ◽

Biological Water ◽

Small Streams

This paper outlines the research being undertaken by the recently-initiated four-year (to March 2022) project on the small stream network in Ireland (SSNet) funded by the Irish Environmental Protection Agency (EPA). The overarching objective of SSNet is to advance knowledge on the role of small streams in water quality, biodiversity and ecosystem services protection that will inform policy, measures and management options to meet water quality and other resources protection targets. The project will start with a synthesis of available information on the importance of small streams to initiate communication with stakeholders and introduce the project. This will be followed by a compilation and analysis of existing data on small streams in Ireland to inform the selection of sites for the proposed research. Three work packages will collect new data on hydrochemistry with a focus on the nutrient retention potential of headwater streams, hydromorphology and biodiversity. All three investigations will share common sites to enable interconnections between the three elements to be explored and provide an integrated approach to the research. Modelling based on the results from each of the aforementioned tasks will be used to estimate the level of intervention in the small stream network required to have measurable effects throughout a catchment on both water quality (N, P & sediment) and flows, and overall delivery/maintenance of ecosystem services. We will also engage volunteers in both biological water quality and hydromorphological assessments and evaluate the potential of citizen science in facilitating greater monitoring coverage of the small stream network.

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Modelling the impact of increased lateral connectivity on nutrient retention in Austrian Danube floodplains

10.5194/egusphere-egu2020-18887 ◽

2020 ◽

Author(s):

Martin Tschikof ◽

Stephanie Natho ◽

Thomas Hein ◽

Elisabeth Bondar-Kunze

Keyword(s):

Water Quality ◽

National Park ◽

Nutrient Retention ◽

Danube River ◽

Retention Rates ◽

Nutrient Loads ◽

Lateral Connectivity ◽

The Danube River ◽

Nutrient Emissions ◽

Semi Empirical

In the last centuries, rivers in Central Europe have severely suffered from hydro-morphological alterations and excessive nutrient inputs. Their adjacent floodplains have the ability to retain transported nutrients in case of inundation, but are subject to progressing decoupling from the main river stem. In the Austrian Danube Floodplain National Park, restoration measures have been carried out and are planned for the near future to increase lateral connectivity in accordance with navigation purposes.We investigated nutrient retention capacity in seven differently connected side arms and the potential effects of further proposed reconnection measures using two complementary modeling approaches. With existing monitoring data on hydrology, nitrate and total phosphorus concentrations for three side arms, we derived a multivariate statistical model and compared these results to a larger scaled semi-empirical retention model (Venohr et al. 2011). We modelled nutrient retention at current state and after completion of side arm reconnections in a dry (2003) and wet (2002) hydrologic year.Both models show comparable annual retention rates and agree in calculating higher nutrient retention in floodplains where reconnection allows more frequent inundations at low discharges. The semi-empirical approach results in highest retention rates at low hydraulic loads and shows more reasonable results at high floods. On the other hand, the statistical approach predicts increasing retention rates with higher nutrient loads entering the side arms and also takes into account nitrate reduction in the remaining water bodies at times of no surface water connection.Our results suggest that water quality of the Danube River could be improved by increasing parameters related to lateral connectivity between river and floodplain. These include in particular the frequency and area of inundation, as well as nutrient input loads into the reactive zones of floodplains. Still, a frequently hydrologically connected national park stretch after restoration reduces nutrient loads of the Upper Danube by less than 0.1% due to its small areal extent in relation to transported river nutrient loads. In order to sustain an adequate water quality in future, both a reduction in nutrient emissions and a larger area of functional floodplains along the Danube River are required.References:Venohr, M., Hirt, U., Hofmann, J., Opitz, D., Gericke, A., Wetzig, A., ... & Mahnkopf, J. (2011). Modelling of nutrient emissions in river systems&#8211;MONERIS&#8211;methods and background. International Review of Hydrobiology, 96(5), 435-483.Key words:River floodplains, lateral connectivity, nutrient retention, river restoration, floodplain reconnection, water quality

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VEgetation NUtrient-retention Service (VENUS) index: an indicator to assess favourable conditions for nutrient retention by vegetation.

10.5194/egusphere-egu2020-20080 ◽

2020 ◽

Author(s):

Davide Murgese

Keyword(s):

Water Quality ◽

Riparian Vegetation ◽

Nutrient Retention ◽

Water Bodies ◽

Complete Analysis ◽

Retention Performance ◽

Hydrogeological Model ◽

Management Scenarios ◽

Management Measures ◽

Definition Of

Ecosystems role in preserving water resources is acknowledged by EU Water Framework Directive 2000/60/EC and by Groundwater Directive 2006/118/EC. In this view nutrient concentration represent a critical aspect with regard to water quality and eutrophication. Nitrate pollution is specifically addressed by the Nitrate Directive 91/676/EEC, which provides nitrate management rules for farming activities, defines nitrate vulnerable zones and gives indications on nitrate monitoring in water bodies.To preserve water quality levels an important role is played by Riparian Buffer Zones (RBZ) through the provision of the Ecosystem Service (ES) nutrient retention, the uptake process operated by plant roots. Research has shown how ES valuation is a very effective approach to support land management process, as it allows a better understanding of the importance of the role of ecosystems in guaranteeing wellbeing conditions for human communities and for the environment.In order to perform a complete assessment of ES, the use of maps only providing information on processes occurring at/above the surface (e.g land use maps, or ecosystem maps, or ecosystem function maps) does not allow a complete analysis of underground dynamics.In the case of the valuation of the ES &#8220;nutrient retention&#8221; provided by RBZ it is necessary to include the hydrogeological model and its links with the riverine network. The simple presence/absence of vegetation, or even a detailed vegetation classification map, cannot provide a complete description of all conditions required to fully assess this ES, as information on groundwater flow, sediments and soils characteristics is needed.For the Riparian Vegetation Management Plan of the Gesso Stura Riverine Park a specific index to study vegetation contribution to nutrient retention was introduced: the VEgetation NUtrient-retention Service (VENUS) Index. This index provides land managers a semi-quantitative indication on the spatial distribution of &#8220;best conditions&#8221; (suitability map) for nutrient retention by vegetation; it is based on a simple set of parameters representing the main factors controlling the interactions between vegetation roots and water flows (runoff and groundwater) from surrounding areas towards water bodies.The application of the VENUS Index improved the definition of management measures for riparian vegetation and allowed reaching the following results: (1) identification of homogeneous sectors in terms of RBZ relevance for nutrient retention; (2) assessment of different RBZ management scenarios with regard to nutrient retention performance; (3) definition of specific management measures to preserve and/or foster the provision of nutrient retention.

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