soil biological indicators organic farming systems l.
Download
Skip this Video
Loading SlideShow in 5 Seconds..
Soil biological indicators: Organic Farming Systems PowerPoint Presentation
Download Presentation
Soil biological indicators: Organic Farming Systems

Loading in 2 Seconds...

play fullscreen
1 / 16

Soil biological indicators: Organic Farming Systems - PowerPoint PPT Presentation


  • 206 Views
  • Uploaded on

Soil biological indicators: Organic Farming Systems. Dr. Rachel Creamer, Prof. Bryan Griffiths Johnstown Castle Environment Research Centre. Acknowledgements: A Bispo – ADEME, Karl Ritz – Cranfield University, Scottish Agricultural College, SCRI, Dundee.

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about 'Soil biological indicators: Organic Farming Systems' - giles


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
soil biological indicators organic farming systems

Soil biological indicators: Organic Farming Systems

Dr. Rachel Creamer, Prof. Bryan Griffiths

Johnstown Castle Environment Research Centre

Acknowledgements: A Bispo – ADEME, Karl Ritz – Cranfield University,

Scottish Agricultural College, SCRI, Dundee

why soil biology as indicators
Soil harbours most of the world’s biodiversity

Responsible for many key ecosystem functions

Turnover 50,000 kg fresh material ha-1 yr-1

Predicted 20 MT CO2-C yr-1 sequestered (NL)

Soil fauna represent 10% of biomass but are responsible for 30% of N mineralisation

Cycling of energy and nutrients intimately associated with the soil food web

Why soil biology as indicators?
comprehensive set of field measurements
Soil Physics – air permeability, bulk density, total porosity, macroporosity, available water capacity, and water repellency

Soil chemistry – NO3-, NH4+, DOC, DON, pH, soil C:N

Soil function – Potential nitrification and denitrification rates in lab assay. - Monthly in situ gas fluxes, CO2, N2O

Microbiology – Nucleic acid analysis of: nitrifiers, denitrifiers, methanotrophs, eubacteria and fungi. - ELFA, ester-linked fatty acids.

Soil animals – counted and identified where possible to species.

Earthworms, Microarthropods, Nematodes, Protozoa

Comprehensive set of field measurements

Samples taken in 2006 (summer, autumn) and 2007 (spring, summer, autumn). Analytical completion planned for end March 2008

slide14

Arable

Model Control

Grassland

  • Control
      • All parameters at medium values
  • Grassland Organic System
      • Increase in decomposition /

biodiversity and recovery of losses

  • Arable System
      • Added manure increased:

decomposition / physical strength/

chemistry / biodiversity

BUT increased losses of leachates and gases

literature overview
Marinari et al., 2006 (Ecological Indicators)

The field under organic management showed significantly better soil nutritional and microbiological conditions; with increased level of total nitrogen, nitrate and available phosphorus, and an increased microbial biomass content, and enzymatic activities (acid phosphatase, protease and dehydrogenase). No consistent increase in total organic carbon was observed.

Birkhofer et al., 2008 (Soil Biology and Biochemistry)

Long-term organic farming and the application of farmyard manure promoted microbial biomass and fostered natural enemies and ecosystem engineers. Application of farmyard manure increased the activity and biomass of decomposer biota. Mineral fertilizers and herbicide application, reduced natural pest control. The combined application of mineral and organic fertilizers appeared to counteract beneficial effects of organic fertilizers, such as enhanced microbial biomass or reduced pest abundance. However 23% higher yields in systems receiving min fertilisers and herbicides

Fließbach et al., 2006 (Agriculture, Ecosystems and Environment)

Both organic C and biological soil quality indicators were clearly dependent on the quantity and quality of the applied manure types, but soil microbial biomass and activities were much more affected than organic C.

Literature overview
conclusions
Organic systems – beneficial for soil biological communities

Type and quantity of organic matter is important

Assessment of soil biology can inform on the quality status of soils

Presence of different trophic groups within Taxa is the best indication e.g. feeding groups of nematodes

Conclusions