Update of COGAP and adoption by signatory states

J Webb

Framework advisory COGAP for reducing ammonia emissions

• Draft Version, 25 September 2000– Editors: B. Pain; H. Menzi– With contributions from: – H. Döhler, Germany– H. Hendriks, Netherlands– A. Jagusiewicz, UN/ECE – H. Menzi, Switzerland– J. Webb, United Kingdom

COGAP requirements

• ‘Within one year of the date of entry into force of the Gothenburg Protocol, a Party shall establish, publish and disseminate, an advisory code of good agricultural practice to control NH3 emissions’

COGAP requirements

• ‘The national code shall take into account the specific conditions within the territory of the Party i.e. be tailor-made to local soil and geomorphological conditions, manure types and farm structure’

COGAP requirements

• ‘However, in order to harmonise some basic requirements of national codes and to incorporate the best available control options and techniques, the UN/ECE Expert Group on Ammonia Abatement was requested to prepare a framework advisory COGAP based on the experience and knowledge of its members’

COGAP requirements

• ‘This code includes provisions on all major agricultural sources of ammonia emissions, and particularly on N management, taking account of the whole nitrogen cycle. It is intended to help Parties to develop and/or elaborate their own advisory codes of good agricultural practice to control NH3 emissions’

COGAP contents

• The Code comprises six sections:• nitrogen (N) management that takes into account the

whole N cycle• livestock feeding strategies• low emission manure spreading techniques• low emission manure storage techniques• low emission animal housing systems• limiting emissions from the use of mineral N

fertilisers

N management that takes into account the whole N cycle

• It is important to consider the whole N-cycle in devising effective strategies for minimising both water and atmospheric pollution, optimising N use for crop production and taking into account the effects of NH3 abatement on other N losses

N management that takes into account the whole N cycle

• Balanced N applications– the benefits of balanced fertilisation for NH3

abatement are less immediate, although good management of fertilisers and manures can make a useful contribution

– excess N application can increase concentrations in grass and hence in the urine of grazing animals, leading to greater NH3 emissions

Livestock feeding strategies

• Ensuring that livestock are not fed more protein than that required for the target level of production can reduce the N excretion per livestock and production unit

• decreasing the amount of N in manures will not only abate NH3 emissions but also other potential N losses (nitrate, nitrous oxide).

Livestock feeding strategies

• Surplus protein is mainly excreted as urea (uric acid in poultry manure)

• these compounds are rapidly degraded to ammonium

• reducing N excretion, therefore, gives a disproportional decrease in NH3 losses

• furthermore, abatement occurs at all stages of manure management

Low emission manure spreading techniques

• Ammonia emissions from the application of manures account for a large proportion of the emissions from agriculture

• it is important to minimise losses at this stage of management because NH3 saved earlier, from livestock housing or manure storage, may be partially lost if it is not controlled at field application

Low emission manure spreading techniques - slurry

• Injection– shallow (or slot) injectors– deep injectors

• arable injectors

• trailing hoses

• trailing shoes (or feet)

Low emission manure spreading techniques - slurry

Technique % Abatement

Trailing hose 10-50

Trailing shoe 40-60

Shallow injection open 50-70, closed 70-90

Deep injection 70-90

Incorporation 20-90

Low emission spreading - FYM and poultry manure

• Incorporation– the aim should be to incorporate slurry into the

soil as rapidly as possible after spreading on the surface

– it is normally recommended that incorporation should be completed within 6 hours of spreading to achieve worthwhile abatement.

Low emission spreading - other techniques

• The following techniques can help to reduce NH3 emissions but are not as effective or reliable as those outlined above– time of application– dilution of slurries– mechanical separation of slurries

Low emission manure storage

• Surface area– reduce the surface area (or emitting surface) of

the store– the surface area of a 1000 m3 slurry store can be

reduced by 1/3, if the height of the sides is increased by 2 m from 3 to 5 m

Covers for slurry tanks or silos

• Roofs etc– the most effective techniques for reducing NH3

emissions but also the most expensive

• floating covers– these are usually made from plastic sheets and

are less effective than roofs but cheaper

• natural crusts

Low emission manure storage - efficiencies

Cover Efficiency

rigid roof 70-95

flexible/floating 60

natural crusts 35-50

LECA balls etc 60-90

Storage of solid manure

• At present there are no proven techniques for reducing NH3 emissions from stored solid manures

• management guidelines for limiting NH3 emissions are as follows

Storage of solid manure

• Cover solid manure stores– this will reduce NH3 emissions but is

impractical when manure has to be loaded frequently

• make the surface area of the stack as small as possible

• keep poultry manure as dry as possible

Low emission animal housing systems

• Slurry-based pig houses– reduce the surface area of the slatted area – reduce the exposed surface of the slurry

beneath the slats– lower slurry temperature– improve animal behaviour and design of pens

Low emission animal housing systems

• Straw-based pig houses– manage bedding to ensure pigs have a clean,

dry bed– ensure that drinkers and troughs do not leak– prevent urine accumulation

Low emission animal housing systems

• Low emission systems for poultry buildings– NH3 emissions are minimal when the dry matter

content of manure or litter is 60% or above– belt systems– stilt houses

Limiting NH3 emissions from the use of mineral fertilisers

• Limiting NH3 emissions from urea

– incorporate the urea into the soil– spread urea in the right weather– urease inhibitors