André Vézina, ITA, La Pocatière Campus

Benefits of Installing Shelterbelts

April 2006

André Vézina, ITA, La Pocatière Campus

Reasons for planting shelterbelts around livestock buildings

Odour mitigation Reduction of heating costs Control of snow accumulation Reduction of air-conditioning costs Reduction of dust volume Protection for livestock Aesthetic enhancements to surroundings Enhanced biodiversity Secondary productions Reduction of greenhouse gas emissions

André Vézina, ITA, La Pocatière Campus

How shelterbelts help mitigate odours(Tyndall and Coletti, 2000)

Dilution of gas concentrations

Dust and aerosol deposition

Interception of dust and aerosols

Absorption of chemical constituents of odours

André Vézina, ITA, La Pocatière Campus

Dilution of gas concentrations

André Vézina, ITA, La Pocatière Campus

If temperatures are favourable, and if the site topography is flat and free of obstacles, air circulation close to the ground will cause objectionable odours to be less noticeable.

André Vézina, ITA, La Pocatière Campus

Shelterbelt Quiet zone

Turbulent zone (plume dilution)

Distance from shelterbelt (H)

(Adapted from Raine, 1974, as used in McNaughton, 1988)

André Vézina, ITA, La Pocatière Campus

Artificial windbreaks used to deflect ventilated air upward, so that foul air flows higher above the ground, can noticeably reduce odours downwind (OCTF, 1998; Bottcher et al., 1999).

André Vézina, ITA, La Pocatière Campus

Dust and aerosol deposition

André Vézina, ITA, La Pocatière Campus

Air containing dust particles can carry a greater amount of odour-producing molecules than the same volume of dust-free air (OCTF, 1998).

In average, a windbreak with a porosity of 40% will reduce wind velocity by 50% over 10 H, and by 25% over 10-20 H (Vézina, 1985).

This reduction will cause wind-borne particles to be deposited.

André Vézina, ITA, La Pocatière Campus

Wind tunnel modeling of a three-row shelterbelt system has quantified reductions of 35-56% in the downwind mass transport of odorous particles (dust and aerosols) (Laird, 1997; Thernelius,1997).

Other studies have shown a 70-90% reduction in pesticide concentrations on the lee side of shelterbelts made of hardwoods (Porskamp et al., 1994).

André Vézina, ITA, La Pocatière Campus

Interception of dust and aerosols

André Vézina, ITA, La Pocatière Campus

Absorption of chemical constituents of odours

André Vézina, ITA, La Pocatière Campus

Significant quantities of volatile organic compounds have been measured on the surface of plants and within plant tissues (Reischl et al., 1989; Gaggi et al., 1985).

Micro-organisms that dominate the surface of plants absorb volatile organic compounds, thus providing additional surface area for pollution collection. These organisms also have the ability to metabolize and breakdown volatile organic compounds (Screiber and Schonherr, 1992; Mueller, 1992).

André Vézina, ITA, La Pocatière Campus

Choinière Project (2004): Evaluating the performance of mature shelterbelts in mitigating odours

André Vézina, ITA, La Pocatière Campus

F factor (odor limits)

Reduction in length of odour plumes by 19%, 23% and 25% compared to control

Distance

Source/wb

Odor plume length Length reduction

No windbreak

André Vézina, ITA, La Pocatière Campus

Reduction in surface area of odour plumes by 30%, 33% and 37% compared to control

Distance Source/wb

No windbreak

Odor plume area Length reduction

André Vézina, ITA, La Pocatière Campus

Odour dilution is enhanced by a ratio of 1.9, 3.2 and 5.1, respectively at distances of 60 m, 30 m and 15 m.

Hardwoods

Conifers

Average (Hdw-Cnf)

Average dilution ratio vs. distance between odour source and hedge

André Vézina, ITA, La Pocatière Campus

10-15% in NE USA (Heisler and De Walle, 1988) 27% in Western Canada (PFRA)

(1.2% per km/h in wind speed in unprotected areas)

Reduction in heating costs

André Vézina, ITA, La Pocatière Campus

Shading created by trees and shrubs can lower temperatures by 10-14°C, thus reducing air-conditioning costs by 50-70% (Gaudet, 1985). The trees should be planted on the western side of the buildings to ensure optimal protection during the summer without significantly reducing solar radiation during the winter (USDA, 1985).

André Vézina, ITA, La Pocatière Campus

Control of snow accumulation

André Vézina, ITA, La Pocatière Campus

Improved weight gain and reduced death rate in livestock.

André Vézina, ITA, La Pocatière Campus

Shading is beneficial to animals. For example, milk production starts to decline when temperatures exceed 20°C (Hintz, 1983).

André Vézina, ITA, La Pocatière Campus

A dense hedge of trees and shrubs has been shown to reduce by one-third the volume of decibels generated by normal road traffic in a peri-urban area in Nebraska (Cook and Van Haverbeke, 1976).

André Vézina, ITA, La Pocatière Campus

Shelterbelts have the ability to collect a portion of air-borne dust particles. According to Dochinger (1980), dust fall can be reduced by 38% with the use of coniferous shelterbelts and by 27% with hardwoods, compared to an area that contains no trees.

André Vézina, ITA, La Pocatière Campus

Aesthetic enhancements to surroundings

André Vézina, ITA, La Pocatière Campus

Enhanced Biodiversity

Presence of trees and shrubs is of considerable help in enhancing biodiversity (Boutin et al., 2003; Deschênes et al., 2003; Maisonneuve and Rioux, 2001).Their study included six types of buffer strips: grasslands, grass-like strips, low-growing scrublands, high-growing scrublands and wooded hedgerows. It is in these wooded hedgerows that the highest population and greatest diversity of birds was found as well as the highest populations of amphibians and reptiles. The total number of small mammals captured increases from grasslands to scrublands to wooded hedgerows.

André Vézina, ITA, La Pocatière Campus

Secondary productions

Wood

Berries

Nuts

Branches

André Vézina, ITA, La Pocatière Campus

Hybrid poplars

110 clones

Lapotika Farm,

La Pocatière

André Vézina, ITA, La Pocatière Campus

Planted en 1981, harvested in 2005

André Vézina, ITA, La Pocatière Campus

Yield

1 m3/tree 90% lumber 7 trees/cord

André Vézina, ITA, La Pocatière Campus

We expect better results from some selected clones

André Vézina, ITA, La Pocatière Campus

Study conducted on 10 shrub species (La Pocatière, 2004-2006)

André Vézina, ITA, La Pocatière Campus

Preliminary results (www.cepaf.ca)

Sambucus canadensis, aronia melanocarpa, viburnum trilobum and rosa rugosa gave the best yields among the shrubs under investigation.

Sambucus canadensis show the best yields (1,25 kg per plant), but we expect the plants to give more as they reach their full production potential.

André Vézina, ITA, La Pocatière Campus

Branches

Trends in floral design have increased the demand for branches from a number of shrubs with decorative flowers and fruits, as well as branch form and color. A study is underway under the leadership of Bruno Moser, head of Purdue's Department of Horticulture, to develop a sustainable system to produce economic shoots of a number of plant species including the Salix caprea (pussy willow) and S. matsujdana tortuosa (corkscrew willow).

André Vézina, ITA, La Pocatière Campus

Reduction of greenhouse gases

Evolution of carbon emissions in Canada with and without Kyoto Protocol application

(Rochette, 2000)

André Vézina, ITA, La Pocatière Campus

This 3 row model is capable of sequestering 300 tons of carbon per kilometre of windbreak within a 40-year timeframe (PFRA (1997).By planting annually 100 km of hedgerows by 2010 in eastern Canada , it would be possible to mobilize, in 40 years, a total of 0,2Mt of CO2, which

represents 0,03% of the forecasted annual production in Canada in 2010. A small step in the right direction…

André Vézina, ITA, La Pocatière Campus

Inconveniences

Rodents (negligible)

Birds (negligible)

Higher odour concentrations in the area between the

shelterbelt and the source of the odour

Increase (3°C) in air temperature within protected area