Conversion to Extensive Grass Land

Content Table

• Conversion to Extensive Grass Land
  • General description
  • Pros and Cons
    • Pros
    • Cons
  • Literature and Links
  • Case studies
  • Related Publications from IWA
  • Articles in this Series
  • ConversiontoextensivegrasslandforFloodRiskManagement

General description

Conversion to Extensive Grassland means changing arable crop to permanent grassland, which is either no grazed or has a low stocking rate and zero or low fertiliser input. The main focus of the measure is reducing erosion of soil particles and decreasing losses of nitrate and phosphorus. High nutrient input leads to eutrophication, one of the main problems of water quality (WFD 2009). Flood protection is a secondary effect of the conversion to extensive grassland, through increased infiltration (additional preventing soil silting) and slowed down surface runoff due to high roughness. The hydrologic- hydraulic effect varies depending on the vegetation, the soil condition at the time of conversion (compression, water conductivity) and the season. The method is applicable to all forms of arable farmland (especially suitable for land historically kept as grazing land). Attention is necessary if the field contains endangered arable weed species. Benefits will be the greatest on sandy and silty soils that are most prone to erosion. Conversion to extensive grassland effects in medium (flood protection) to long terms (decrease nutrients).

Introduction of land set-aside:

• Develop a site- and open space typical and species-rich permanent grassland,
• When possible, use only seed from the area, alternatively, application of meadow cut (hay harvest).
• The spontaneous development of extensive grassland species from the seed bank or through immigration should be additional approved,
• Previous impoverishment of the site by biomass removal over two to three times cut per year between the end of May and October,
• About 10 to 50 m distance from extensive developing Grassland to intensive arable land necessary to prevent the risk of eutrophication,
• The steps to take care of development activities shall be based on the location and target habitat types (e.g.thin mountain meadow, mesophilic grassland)
• Extensive or less intensive use or no use of pesticide application, saving manure management, drainage, leveling the ground relief, plowing up the grassland
• Mowing/ grazing potential meadow bird breeding areas have to be individually coordinated with the founded breeding places.

Cultivation Meadow:

• One or two cuttings a year from June to October as a mosaic of different times cut areas,
• Mowing of plots as possible from the inside out or from one to the other side,
• As possible use of cutting, not beating mowing machines, no use of drawing mowing machines,
• Cutting height of not less than 10 cm,
• Removal of the harvest

Cultivation pastures:

• Year-round grazing,
• Stocking capacity not more than three cattle per hectare,
• Use as permanently pastures is possible, exclude unused edge strips and waters,
• Avoid soil compaction by grazing animals or driving compaction as a result of fertilization, mowing, haymaking etc.

Costs/promotion possibilties :

• varying seed cost depending on seed (special flower-filled mixture can cost 10 to 15 times the usual mixture)
• Process costs: depending on the size of the cultivating area,
• promotion possible depending on the landscape (nature protection area)  and use of the extensive grassland (e.g. 124€/ha for 5 years)

A cost benefit analysis has to be done separately for each individual project. A possible procedure and the coast range for alternative solutions you will find here (link).

Pros and Cons

Pros

• Permanent vegetation cover minimises the erosion of soil particles
• Groundwater protection trough reduction of nitrate leaching,
• Reduction of phosphorus losses in surface runoff
• Increase the infiltration of rainwater by high roughness and prevented soil silting,
• Reducing the flow velocity of surface run off
• Improvement of habitat and biotope networking function for plant and animal species characteristic of open land (particularly potential grassland bird- nesting areas, bird resting places),
• Appreciation of the landscape and increased the effectiveness of the experience of landscape (depending on the grassland proportion of the landscape)
• Easy to implement and maintain

Cons

• Loss of income for farmers (depending on the agricultural structure and crop rotation).
• Harvest reduction possible, depending in site-specific yields, crop rotation and the possibilities of using pasture yield (feed, biogas)
• only slow (mores than 10 years) reduction of soil phosphorus content (for soils previous intensive fertiliser) caused by low off- takes by extensive systems

Literature and Links

• WFD (2000): Water frame work directive, Directive  2000/60/EC of the European Parliament and of the Council of 23 October 2000 establishing a framework for Community action in the field of water policy
• SIEKER, F. (2007): Maßnahmensteckbrief "Umwandlung von Acker in extensives Grünland", In: Istitut für Wasserwirtschaft, Hydrologie und Landwirtschafltichen Wasserbau: Abschlussbericht zum Forschungsprojekt "Vorbeugender Hochwasserschutz durch Wasserrückhalt in der Fläche unter besonderer Berücksichtigung naturschutzfachlicher Aspekte - am Beispiel des Flusseinzugsgebietes der Mulde."
• DWA Deutsche Vereinigung für Wasserwirtschaft, Abwasser und Abfall (2005) Dezentrale Maßnahmen zur Hochwasserminderung,
• Floodplain Management
• Macleod, C.J.A. 1, Blackstock, K.L., Haygarth, P.M.(2008): Mechanisms to Improve Integrative Research at the Science-Policy Interface for Sustainable Catchment Management, Appendix 1, link
• Reisinger (2009): Kosten zur Biodiversitätssicherung (in German)

Case studies

Floodplain management Elbe, Germany

A SAWA case study was done by the Chamber of Agriculture, Lower Saxony (Landwirtschaftskammer Niedersachsen), Germany. The study is related to the SAWA-Project „Flood control and prevention in cooperation with rural development to reduce the inundation risk on agricultural land“.
With the increase of extreme rainfall due to Climate Change, the issue of nutrients and pollutants distribution on farmlands in floodplains is becoming more important. More information is necessary on how these flood plain areas can be successfully used by farmers, as they are an essential part within integrated and sustainable land use. This project will provide recommendations on how to integrate sustainable water management, flood information and contamination risk data into a spatial land use management for rural characterised floodplains. detailed description

Related Publications from IWA

Edit

Water, Wastewater and Stormwater Infrastructure Management - Neil S. Grigg 
Publication Date: Jul 2012 - ISBN - 9781780400334

Articles in this Series

Flood hazard maps

Cost range of measures concerning to flood protection

Flood Adaptive Architecture

Cost benefit analysis

Depth Loosening

Rainwater Harvesting

Groundwater Defence

Infiltration and retention structures

Green Corridors / Strips

Conversion to Extensive Grass Land

Decision Support Tools - Planning