Agriculture - Fertiliser pollution

Title

Application of SWAT model to small agricultural catchment in Poland

Reference

Journal of Land and Water Development. 15; 157-166

Author(s)

Jan Brzozowski, Zygmunt Miatkowski, Damian Śliwiński, Karolina Smarzyńska, Maria Śmietanka

Study type

Peer Review Journal    

Abstract

Poland is obliged, like the other EU countries, to implement the Water Framework Directive - WFD (2000/60/WE) by the end of 2015. The main objective of WFD is to provide normative quality of all water resources. To reach this goal reduction of water polluter emission to the environment is needed. Our project focuses on pollution from agricultural sources which share in global pollution is high and growing still. As a pilot area, where the WFD is going to be implemented, small agricultural Zgłowiączka catchment was chosen.
The state monitoring of surface water quality for the catchment is conducted in three points along the Zgłowiaczka River. In each of these three points, nitrates concentration periodically significantly exceeds the allowable value of 50 mg NO3·dm-3. The highest average monthly values of nitrates concentration in years 1990-2007 occur in February, March and April, which indicates on agriculture as a source of pollution. The Zgłowiaczka catchment is an area where reduction of nitrogen run-off from agricultural lands to water resources is especially needed. The main topic of the research carried out in the Polish-Norwegian project is to propose different means for reduction of migration of nitrate to surface water based on modeling approach. In the paper a conception of creating buffer zones using SWAT model is presented. We considered fitting the buffer zone width, depending on the flow rate of water flowing from the fields to the stream. Using SWAT model interface a map of potential flow under the conditions of the intensive precipitation was generated. The next step was distribution over the whole Zgłowiączka catchment, places with high density of the temporal streams network. It was done using GRASS program. The map of stream "density" was done by assigning the raster number which is the sum of raster in the neighbourhood (radius of neighbourhood smaller or equal 25 raster). The choice of the most endangered subbasins was done on base of visual evaluation of the surface flow density map.
It is visible in the results that filter strips on endangered areas are far more effective and therefore more required. If the width of the vegetated buffer strips is not sufficient, it will not attain the desired effectiveness. Conversely, if the width is too great, it will cause agricultural land waste, preventing farmers' interest in cooperating with environmental preservation efforts. For the above reasons, it is important to set a reasonable width range. According to the results we are suggesting wider buffer zones in endangered subbasins and narrow in other subbasins.

Policy theme(s)

Agriculture >> Agricultural pollution >> Fertiliser pollution
Water >> River basin management (WFD)                          
Water >> Water quality >> Water pollution and safety

Keywords

agriculture, nitrate, diffuse pollution, SWAT, buffer strips

Entry Source:

Shortlisted for Science for Environment Policy News Alert 

Selected for Science for Environment Policy News Alert

View this study at:

http://versita.metapress.com/content/mu57921875828357/
This study is free to view

Contact the study author at:

Jan.brzozowski@gmail.com

Title

Biodiversity improves water quality through niche partitioning

Reference

Nature, Volume 472, Pages 86-89, 07 April 2011
DOI:doi:10.1038/nature09904

Author(s)

Bradley J. Cardinale

Study type

Peer Review Journal

Abstract

Excessive nutrient loading of water bodies is a leading cause of water pollution worldwide, and controlling nutrient levels in watersheds is a primary objective of most environmental policy. Over the past two decades, much research has shown that ecosystems with more species are more efficient at removing nutrients from soil and water than are ecosystems with fewer species. This has led some to suggest that conservation of biodiversity might be a useful tool for managing nutrient uptake and storage, but this suggestion has been controversial, in part because the specific biological mechanisms by which species diversity influences nutrient uptake have not been identified. Here I use a model system of stream biofilms to show that niche partitioning among species of algae can increase the uptake and storage of nitrate, a nutrient pollutant of global concern. I manipulated the number of species of algae growing in the biofilms of 150 stream mesocosms that had been set up to mimic the variety of flow habitats and disturbance regimes that are typical of natural streams. Nitrogen uptake rates, as measured by using 15N-labelled nitrate, increased linearly with species richness and were driven by niche differences among species. As different forms of algae came to dominate each unique habitat in a stream, the more diverse communities achieved a higher biomass and greater 15N uptake. When these niche opportunities were experimentally removed by making all of the habitats in a stream uniform, diversity did not influence nitrogen uptake, and biofilms collapsed to a single dominant species. These results provide direct evidence that communities with more species take greater advantage of the niche opportunities in an environment, and this allows diverse systems to capture a greater proportion of biologically available resources such as nitrogen. One implication is that biodiversity may help to buffer natural ecosystems against the ecological impacts of nutrient pollution.

Policy theme(s)

Agriculture >> Agricultural pollution >> Fertiliser pollution
Biodiversity >> Ecosystem services >> Ecosystem service identification
Water >> Water quality >> Water pollution and safety

Keywords

Ecology, Earth Science, Environmental Science

Entry Source:

N/A

Referred to in EC doc:

Shortlisted for Science for Environment Policy News Alert

View this study at:

http://www.nature.com/nature/journal/v472/n7341/full/nature09904.html
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Contact the study author at:

bradcard@umich.edu

Title

Ex-ante institutional compatibility assessment of policy options: methodological insights from a case study on the Nitrate Directive in Auvergne, France

Reference

Journal of Environmental Planning and Management,
Volume 54, Issue 5 June 2011 , pages 661 - 684 DOI:10.1080/09640568.2010.527128

Author(s)

Laurence Amblard; Carsten Mann

Study type

Peer Review Journal

Abstract

The Procedure for Institutional Compatibility Assessment (PICA) has been developed as a formalised methodology to predict the compatibility between a policy option and the institutional context of its implementation. As a first empirical test of the tool, PICA was applied to the implementation of the EUNitrate Directive in Auvergne, France. Valuable insights were acquired on thecombination of experts and stakeholders' perspectives and the choice of qualitative methods for the collection of the information needed at each step ofthe assessment. Further, this procedure proved to be a valuable tool for the ex-ante identification of institutional factors affecting the implementation of policies.

Policy theme(s)

Agriculture >> Agricultural pollution >> Fertiliser pollution
Environmental information services >> Environmental communication >> Stakeholder/public engagement

Keywords

ex-ante policy assessment, institutional compatibility, EU Nitrate
Directive, integrative methodology

Entry Source:

Selected for Science for Environment Policy News Alert

Referred to in EC doc:

N/A

View this study at:

http://www.tandfonline.com/doi/abs/10.1080/09640568.2010.527128  
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Contact the study author at:

laurence.amblard@cemagref.fr

Title

Agronomic phosphorus imbalances across the world's croplands

Reference

Proceedings of the National Academy of Sciences, 2011;
DOI: 10.1073/pnas.1010808108

Author(s)

G. K. MacDonald, E. M. Bennett, P. A. Potter, N. Ramankutty.

Study type

Peer Review Journal

Abstract

Increased phosphorus (P) fertilizer use and livestock production has fundamentally altered the global P cycle. We calculated spatially explicit P balances for cropland soils at 0.5° resolution based on the principal agronomic P inputs and outputs associated with production of 123 crops globally for the year 2000. Although agronomic inputs of P fertilizer (14.2 Tg of P y-1) and manure (9.6 Tg of P y-1) collectively exceeded P removal by harvested crops (12.3 Tg of P y-1) at the global scale, P deficits covered almost 30% of the global cropland area. There was massive variation in the magnitudes of these P imbalances across most regions, particularly Europe and South America. High P fertilizer application relative to crop P use resulted in a greater proportion of the intense P surpluses (>13 kg of P ha-1 y-1) globally than manure P application. High P fertilizer application was also typically associated with areas of relatively low P-use efficiency. Although manure was an important driver of P surpluses in some locations with high livestock densities, P deficits were common in areas producing forage crops used as livestock feed. Resolving agronomic P imbalances may be possible with more efficient use of P fertilizers and more effective recycling of manure P. Such reforms are needed to increase global agricultural productivity while maintaining or improving freshwater quality.

Policy theme(s)

Agriculture >> Agricultural management >> Soil management
Agriculture >> Agricultural pollution >> Fertiliser pollution
Water >> Water quality >> Water pollution and safety

Keywords

agriculture, eutrophication, nutrient balances, phosphorous depletion

Entry Source:

Shortlisted for Science for Environment Policy News Alert

Referred to in EC doc:

N/A

View this study at:

http://www.pnas.org/content/early/2011/01/26/1010808108.abstract
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Contact the study author at:

graham.macdonald@mcgill.ca

Title

Cost effectiveness of nitrate leaching mitigation measures for grassland livestock systems at locations in England and Wales

Reference

Science of The Total Environment
Volume 409, Issue 6, 15 February 2011, Pages 1104-1115

Author(s)

L.M. Cardenas , S.P. Cuttle, B. Crabtree, A. Hopkins, A. Shepherd,
D. Scholefield and A. del Prado

Study type

Peer Review Journal

Abstract

As much as 60% of the nitrate in water in England is thought to derive from agriculture. Legislation aims to improve water quality by limiting nitrate concentration in surface and groundwaters to 50 mg l-1. The UK Government responded to the requirements of the EC Nitrate Directive by delineating Nitrate Vulnerable Zones (NVZs) to cover 55% of England in 2002 and increased it to 70% in 2009. In this study we assessed the cost-effectiveness of measures for implementation in livestock systems to mitigate nitrate leaching in the UK. These estimates were prepared for a range of hypothetical farms representative of typical dairy, beef and sheep farms at different locations in England and Wales and for a list of mitigation measures identified to reduce leaching. The NGAUGE and NFixCycle models were used to estimate leaching from these systems. The costs of implementation of the mitigation measures were also assessed in order to evaluate the cost-effectiveness of these measures. In general, the most effective measures to reduce leaching for all systems were the ones that involved a reduction in stocking rates and grazing time, followed by those involving improvements in fertiliser and crop management. Only in the case of the dairy system was effectiveness affected by location of the farm. The costs for implementation in the sheep system were relatively low compared with beef and dairy systems. Implementation of some of the measures with high cost-effectiveness would need to be incentivised financially or with legislation due to the high costs involved.

Policy theme(s)

Agriculture >> Agricultural pollution >> Fertiliser pollution
Water  >> Water quality >> Water pollution and safety

Keywords

Nitrate, Leaching, Modelling, Cost effectiveness, Mitigation

Entry Source:

Selected for Science for Environment Policy News Alert

Referred to in EC doc:

N/A

View this study at:

http://www.sciencedirect.com/science/article/pii/S0048969710013094
There is a fee to view this study in full

Contact the study author at:

laura.cardenas@bbsrc.ac.uk