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ATLANTIC SOIL AND WATER CONSERVATION CHALLENGES

Environmental Farm Planning WorshopCrystal Palace Convention Centre, Moncton, NB

March 30, 2001

Gordon Fairchild, Ph.D., P.Ag., Soils Specialist, ECSWCCand

Jean-Louis Daigle, P.Eng., P.Ag., Director, ECSWCC

Agriculture in Atlantic Canada• climate:

• humid & temperate (high rainfall)

• much is on hilly, rolling land,

• much is on soils naturally susceptible to erosion :

• from morainal deposits

• soils strongly leached, acidic (Podzols)

• soil loamy or sandy in texture

• dense subsoils that impede drainage

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The climate, soils naturally susceptible to erosion, intensive agriculture in some areas, and economic constraints have led to several soil & water conservation challenges for Atlantic Canada

Atlantic Soil and Water Conservation Challenges

•• soil erosionsoil erosion & & soil degradationsoil degradation

•• NPS pollution NPS pollution --fertilizerfertilizer, pesticide & , pesticide & manuremanure useuse

•• water quality water quality & protection of & protection of water water suppliessupplies

•• water water for irrigationfor irrigation

•• habitat & habitat & biodiversitybiodiversity

•• climate climate changechange

The climate, soils naturally susceptible to erosion, intensive agriculture in some areas, and economic constraints have led to several soil & water conservation challenges for Atlantic Canada

Atlantic Soil and Water Conservation Challenges

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M any Atlantic soils show serious soil erosion and degradation

Excessive Soil Erosion by WaterExcess Runoff Soil Compaction Loss of Organic Matter

Loss of Crop ProductivityLoss of Available Soil-Water

Estimated annual on-farm costs at 40 million dollarsin Atlantic Canada by AAFC in 1985

Sol Erosion & Degradation (Soil Quality)

It is estimated that 60-70% PEI & NB potato land experiences excessive soil loss as a result of farming undulated slopes

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AAFC. (1995) The Health of Our Soils

Causes and effects of soil degradation

AAFC. (1995) The Health of Our Soils

Soil Erosion and Degradation

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Soil Management & ConservationSheet & rill soil erosion are being addressed by:1. Better Crop Rotation 2. Strip cropping3. Winter cover crops4. Conservation tillage5. Green manures 6. Residue management 7. Mulching

1,2 3

4 3 & 5

766

8. Cross-slope & contour cropping9. Diversion terraces & grassed waterways10. Sub-surface drainage, subsoiling & 4x4 tractors 11. Straw cover, mulches

8,98

9 10 11

rill & gully soil erosion (steeper fields) by:

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Some progress, with over 20,000 acres in each of NB & PEI protected with appropriate combinations of:

• diversion terraces

• grassed waterways

• strip cropping

• residue management

• mulching

• crop rotation

• cover crops

• etc

Soil Erosion and Degradation

Do Soil and Water Conservation Systems work ?

Site 22

Site 20

AAFC Study - Effectiveness of Terracing SystemsNW NB on NSCP SQEP Benchmark sites 20/22

Cross-slope cultivation, diversion terraces, grassed waterways

Up & down - slope cultivation, no terraces

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Site 22

0 25 50 75

100 125 150 175 200 225

mm

Crg(90) Pa(91) Pa(92) C(93) Pa(94) Moy (90-94)

Terrasse Sens de la pente

Runoff (mm)

0 2 4 6 8

10 12 14 16 18 20 22 24

t/ha

Crg(90) Pa(91) Pa(92) C(93) Pa(94)Moy (90-94)

Terrasse Sens de la pente

Soil loss (t/ha)

terraced terracedUp & down slope Up & down slope

AAFC Study - Effectiveness of Terracing SystemsNW NB on NSCP SQEP Benchmark sites 20/22

Soil and Water Conservation Systems

Runoff & soil loss were greatly reduced on site with soil and water conservation system. Terraces and grassed waterways very effective.

Soil and Water Conservation SystemsChallenges to the Adoption of Conservation Practices:

• Market Pressures & Land Value• Land Availability and Land Tenure• Farming Efficiency & Land Lost• Economics of Soil Conservation ??

Before 1974

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More concern recently for Water Quality & Farm Runoff Issues

Concern for cattle access to streams as a cause of streambankerosion, sediment in streams, soil compaction and coliform

contamination of water & streambank fencing

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Events such as the Walkerton tragedy have served to served to heighten awareness of Water Quality & the protection of Water Supplies

Walkerton E.coli 0157:H7 OutbreakTragedy & Reality

• agricultural runoff was a source of contamination of the well water in the Walkerton tragedy, even if it was not the only cause.

• Agriculture is going to be under increasing public scrutiny and pressure for water quality reasons.

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Heightened public interest in Watercourse Protection & Riparian Management

Ex: NB Watershed & Wellhead Protection for Drinking Water Supplies

aimed mostly at NPS - fertilizer, pesticides & bacteria

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Agriculture

and

Agri-Food

Canada.

(2000)

What is agriculture’s role in water quality ?

Point-source pollution:• industrial plant, smoke stack, etc.

• Easier to identify and control

Non Point-source pollution (NPS):• all of the field or diffuse runoff pollution sources in a watershed, eg: farms, forestry, roads, etc.

• Diffuse source is harder to identify and control

Agriculture is Non Point-source pollution (NPS):

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Surface Water Quality Key issues of surface water contamination in agricultural regions in Canada are:

• sediment

• nutrients

• pesticides

• bacteria

sediment entering surface water

• Sediment enters streams from soil erosion

• sediment can fill in streams and ditches

• sedimentation can reduce or elimination aquatic habitat

• sediment carries with it bound to the sediment:

• nutrients ( N & P) - eutrophication

• organic matter - soil degradation

• pesticides

• bacteria

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Nutrients, bacteria and pesticides enter surface waters chiefly from:

Nitrogen (N): in runoff from fertilizer and manure

Phosphorus (P): mostly as P attached to sediments; some as soluble-P. (soils with high soil test P a problem)

Bacteria: in runoff from manure(tile drains, septic systems, sewage sludge)

Pesticides: in runoff from fields (spills, filling sprayers, spray drift, etc.)

Sediment in farm runoff after very heavy showers (NW NB)

Black Brook 6,000 t / yr ?

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N and P in surface waters

eutrophication - the excess phosphorus (P) in runoff from fertilizer and manure causes a growth of algae in the water.

This algal bloom consumes oxygen in the water, killing fish or reducing aquatic habitat

Nutrients: N and P in surface waters

• eutrophication - nitrogen (N) can sometimes bethe cause eutrophication in estuarine waters. The anoxic conditions may affect aquaculture (shellfisheries) or reduce aquatic habitat

• High NH4+ can also affect fish in streams

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Nutrients: N and P in surface waters

• NB AAFC Black Brook Watershed study, 1992-1994:

concentrations of nutrients in surface water• Nitrate-N ranged 2 to 9 mg/litre (1 mg/litre background)

• Phosphate generally < 100 mg/litre (AB, QC guidelines lower)

• PEI (G. Somers, PEIDFE)

surface water nitrate concentrations have risen, but may have stabilized ?

Pesticides in surface waters

concentrations rarely exceed drinking water guidelines, but sometimes aquatic guidelines

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Bacteria in surface waters

Bacteria can be and are sometimes found in surface waters, particularly near manured fields

Ground Water Quality Key issues of groundwater contamination in agricultural regions in Canada are:

• nitrates (methhemoglobinemia, cancer)

• pesticides

• bacteria

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Agro-chemical entry into groundwater

AAFC. 1995.

The Health of Our Soils

Agro-chemical entry into groundwater

Pesticide movement into groundwater is related to:

• solubility, ….the more soluble a pesticide, the more likely it is to leach into groundwater.

• stability (or persistence)….the longer the pesticide remains, the more likely it is to leach into groundwater.

Our newer generation of pesticides today are less soluble, lower dose, less persistent and less likely to leach into groundwater today than 20-30 years ago.

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Bacteria entry into Ground Water

Usually related to:

• poor well construction (too shallow, poor cap, poor grout, shallow grout, poor initial disinfection)

• wells location too close to manure storage , manure runoff, manure application, or septic systems

• preferential transport through tile drains

• abandoned wells

•etc

Ground Water Quality Nitrate concentrations in groundwater can

be elevated in some intensively agricultural

areas

• some potato production areas• NW NB, Grand Falls, Drummond,

Saint-André

• some BC interior valleys• Abbotford-Sumas aquifer BC

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Ground Water Quality NB, NS, PEI studies….

Pesticides can be found in groundwater,

but are usually well below drinking water

quality guidelines

Ground Water Quality

** Bacteria can be found in groundwater

AB 1995 14 %

QC 1990 26

NB 1985 21

Man 1993 37

PEI 1991 12

NS 1989 9

** indicates « presence » of total coliform, not E. coli 0157:H7

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• Sharing water resources:who gets the top priority?

• Low Flow Maintenance

S oi l an d W ater C on ser vation C h a lle n ge s & Issu es

water quantity issues (both surface & ground water):

• for irrigation

• for habitat & biodiversity

Soil & Water Conservation may now also have to account for Climate Change considerations ?

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Possible Atlantic Climate Change Considerations

• slightly increased annual precipitation ? (or decreased ?)

• increasing climate variability, eg: droughts, floods, temperature ?

• increased frequency of intense rainfalls ?

• warmer winters, earlier & larger runoff ?• growing season and temperature ?

• increase (?)

• decrease (?)

Increased climate variability in the intensityof storm events increased runoff & erosion ?

Drummond NB farm -40 mm intense rainfallevent during 15 min

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•• soil erosionsoil erosion & & soil degradationsoil degradation

•• NPS pollution NPS pollution --fertilizerfertilizer, pesticide & , pesticide & manuremanure useuse

•• water quality water quality & protection of & protection of water water suppliessupplies

•• water water for irrigationfor irrigation

•• habitat & habitat & biodiversitybiodiversity

•• climate climate changechange

The climate, soils naturally susceptible to erosion, intensive agriculture in some areas, and economic constraints have led to several soil & water conservation challenges for Atlantic Canada

Atlantic Soil and Water Conservation Challenges

Tools For Change & Adaptation

• Environmental Farm Plan

• Agri-Conservation Clubs

• BMP Development • Codes of Practice

• Precision Agriculture & Env. Geomatics

• Program Incentives or Tax Benefits

• Economic benefits of S &W Conservation

Self assessment

EFP workbook

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EFP Tools must be an integrated approach

BMPs

Air Quality

Water Quality

Soil Health

The Win-Win Approach

Tools For Change & Adaptation

• Environmental Farm Plan (EFP) Self assessment

EFP workbook

Environmental Farm Planning WorkshopCrystal Palace Convention Centre,

Moncton, NBMarch 29-31, 2001