Our Living Land

Ever look at a coulee along the Oldman River and examine the vegetation on the coulee ridge or the north- and south-facing slopes, or what grows along the coulee bottom? While the plants found in these three areas are very close to each other, they are quite different.

South-Facing Slopes

South-facing slopes are quite warm and dry, and support dry habitat plants— early spring bloomers such as:

nodding onions
	yellow prairie violets and
yellow bells.

The coulee ridges are usually the first to lose whatever snow may accumulate. In addition, they are directly exposed to southern Alberta’s prevailing southwest winds.

Prairie wool, aka  blue grama grass,
	and tufted milk vetch

 are common on these sites.

North-Facing Slopes

The north-facing slopes are slightly cooler and moister since they face away from the sun and are not directly hit by the Chinook winds. Thus, they support a denser vegetation of grasses,

prairie crocuses and
	three-flowered avens.

 Coulee Bottom

The coulee bottom, where moisture seeps down the slopes and drains into the river valley, usually has a strip of

chokecherry bushes,
	often bordered by tall goldenrods.

Effects of Human Activity

The differences reflect small differences in the environment due mainly to topography, even though they all occur in the same region with the same climatic conditions. Ranging from farming to various forms of leisure use of the land, human activities also have a strong influence on vegetation and affect the ecosystem of the land not only where the activities take place, but on other areas as well.

Ecosystems are sensitive to environmental change and one of the most destructive effects on the environment and the ecosystem is human activity. Many of our activities appear harmless, but an examination of the coulees clearly shows the damaging effects years later and continued activities further aggravate the problem.

Despite the fact that coulee cruising was banned many years ago, footpath, bicycle or motorbike trails are strongly evident along most of the ridges and coulee bottoms. A gully can develop on coulee sides where a single motorbike may have been used to climb the slope.

Pavan Park
	Stafford Coulee
Sewage Plant

The erosion caused by riding a motorbike up a coulee slope is little understood by participating riders. While one track may appear to cause little damage, the subsequent erosion can lead to considerable damage.

Urbanization

Clearly, urbanization with the establishment of residential areas and other land development projects affect the land. Not so clearly, the development affects the areas nearby and even some distance away. People watering their lawns can contribute to slumping of coulee slopes. Clay layers below the surface cause excess water to flow horizontally and can destabilize coulee banks. Homes near the destabilized slopes become endangered.

Slumping

Such slumps have occurred in the Park Royal area, both the south and west sides of Tudor Estates, Stafford Coulee, and a recent one in “Snowbowl Coulee”. While coulee slumping has occurred naturally in the past, these slumps are probably directly due to over watering of lawns.

Tudor Slump

Although these are examples of local damage, the problem is widespread.  Virtually all areas are subject to similar human activities. Disturbance of the environment at any level has consequences ranging from scenic losses to serious environmental damage.

Often, the results don't really show up for years, after erosion has time to work. What we do supposedly for our benefit really has an environmental cost that 'neutralizes' supposed benefits causing wide-range concern.

A Question of Development

The overgrazing and logging of the foothills and mountains, especially up until the mid-1900s, is partly responsible for the inability of the region to absorb and hold snowmelt and rainwater. Before, the forest cover and grasslands had a much thicker layer of litter and humus in the soil.  These held large amounts of water and helped it to release slowly over the summer. The advent of logging, especially clear-cut logging, removed large areas of the forest cover.  Subsequently, litter and organic matter, moisture-hold-and-release materials broke down. Heavy grazing by cattle also reduced the ability of the soil to hold moisture. The ability of the land to retain water was greatly reduced. Heavy runoff now occurs in the spring and after any heavy rainfall.

In response to this problem, dams on most of the rivers were constructed to control flooding and to maintain water supplies  for irrigation throughout the summer.  The response further affects our land.  There is little doubt that construction causes destruction. There is no real gain in what we consider development.

In general, what humans consider development is destructive. A change in our perception is required. Ironically, what is good for our own health is also good for the environment. For example, concern over obesity and type II diabetes in our young has resulted in initiatives to educate the general population to get out and walk and to eat unprocessed, slower (closer-to-source) foods. A better response would be to educate land development officers to focus primarily on developing good walking paths; riding; driving and aero paths should quit being a major preoccupation. Reconsidering the speed at which we move about on the land that sustains us would allow the environment time to recover from our impact upon it and would concomitantly improve our health. Covering the land with sidewalks and roadways reduces our ability to see the land for what it is, a living organism that responds to our every activity. It is no wonder, direct use is not a consideration.  If a tree falls in the forest, only those nearby may hear it but we are all very much affected by it—maybe not today, but …

Anyone sensitive to environment and ecosystem issues can help by educating and waking up all levels of governments to the threats on the health of our planet and on ourselves. Common sense should prevail.