Shelter Belts for Soil Protection

What

Shelterbelts are vegetative barriers that are designed to reduce wind speed and provide sheltered areas effectively reducing wind erosion. As wind approaches the shelter belt, some goes around the belt, some goes through the belt, but the biggest volume goes over the top.

Air pressure builds up on the windward side and decreases on the leeward side (the side away from the wind). It is this difference in pressure that drives the shelter effect and determines how much reduction in wind speed occurs and how much turbulence is created.

Why

In regions such as Canterbury where there is a lot of cultivated land, shelterbelts reduce soil erosion by wind, conserve soil moisture and reduce wind damage to crops. They complement good crop residue management and other conservation practices to protect the soil.

Follow the link to see a guide for establishing shelter belts using native plantings. Shelter belt options are possible even under centre pivot irrigation through selecting the right tree species and leaving gaps for wheel tracks.

20 meters of fenceline and a varity of tree species about 10 meters tall.
Example of a mixed native shelter belt.
Image Source: thisNZlife

References

Gregory, N. G. (1995). The role of shelterbelts in protecting livestock: a review. New Zealand Journal of Agricultural Research, 38(4), 423-450.

Kart, J., Collins, M., & Ditsch, D. (1998). A review of soil erosion potential associated with biomass crops. Biomass and Bioenergy, 14(4), 351-359.

Mead, D. (2009). Biophysical interactions in silvopastoral systems: a New Zealand perspective. In Actas del 1º Congreso Nacional de Sistemas Silvopastoriles (pp. 14-16).

Meurk, C.D. Establishing shelter in Canterbury with Nature Conservation in mind. Landcare Research-Manaaki Whenua.

Meurk, C. D., & Swaffield, S. R. (2000). A landscape ecological framework for indigenous regeneration in rural New Zealand-Aotearoa. Landscape and Urban Planning, 50(1-3), 129-144.

Wall, A. J., Mackay, A. D., Kemp, P. D., Gillingham, A. G., & Edwards, W. R. N. (1997, January). The impact of widely spaced soil conservation trees on hill pastoral systems. In: Proceedings of the New Zealand Grassland Association (pp. 171-177).