THE VARIETY OF LIFE

Humans have always influenced the natural environment and all ecosystems go through natural changes. The changes taking place now however, are so rapid and extensive that ecosystems and wildlife are having trouble adapting. The variety of life on Earth is shrinking.

	- Loon;  Photo by Marv Hanson

Wild lands are a cherished part of Canada's cultural and spiritual heritage. Here in Saskatchewan our landscapes are made up of a patchwork of distinct natural regions. The patchwork is shaped by land-forms, soil and climate. All life, including people, depend on these places and their systems for survival.

Humans derive food, medicines, building materials, industrial products and much of our cultural identity from nature. For example, new cures for diseases are regularly found in nature; in North America, more than 40 percent of all prescription medicines depend on natural sources. Many plants are used for herbal remedies for a variety of ills.

People are continually exploring for new ways to utilize nature's organisms. For example, several strains of bacteria found in nature digest certain cells that are proving helpful in cleaning up industrial spills. Fisheries, agriculture and forestry are important economic sectors based on biological resources.

The Web of Life:

All life forms and processes have value simply because they are a living part of the world. If a species disappears from the ecosystem, one strand is removed from the intricate web that supports the variety of life. The more strands that are removed, the weaker the web becomes.

Nature's processes support life. For example, rain falls on the soil, flows across the land, rises into the stems of plants and is released back into the atmosphere.

No species stands alone, each one is essential for the survival and health of ecosystems. While we may think of black flies as annoying pests, fish, birds and amphibians like the frog depend on the larvae of biting flies as an important food source. Another example is the bear who helps spread the seeds of berry plants by first eating the berries and then depositing their remains in its scat further down the trail.

Different plants and animals often support one another while occupying different places (or niches) within a certain area. For example, roots of mushrooms (called fungi) provide nutrients (food) to trees. Young trees grow into large trees and become homes to an array of different animals like squirrels, woodpeckers and beetles. When the tree dies, it falls to the ground and provides a place for rabbits and weasels to live and hide, and for young trees to germinate and grow. As the dead tree decays, nutrients from it's wood and bark leach into the soil and provide a place for mushrooms to grow.

- Stemless Lady Slipper   Photo by Marv Hanson

Diversity within a species is also important to healthy ecosystems. Plants and animals each have their own assortment of inherited (genetic) characteristics. These genes improve the ability of a species to make its way in the world and increase its chances of adapting to changing conditions. For example, color variations within one species of wildflower improves its ability to attract different types of insects. When more insects fly from plant to plant, it is more likely that pollination and reproduction will occur. Genetic diversity can also help species survive a new disease or adapt to a new predator in its region.

Every species requires its special spaces to live and reproduce. Saskatchewan has a rich mosaic of different ecosystems. For example, the Saskatchewan River valley meanders across our province. It is a slow and winding river system, traveling through valleys with deep, productive soils and where river uplands are home to species like coyote, ground squirrel and mule deer. The Churchill River, is a very different ecosystem that also meanders across our province. It is a northern waterway of stream-connected lakes, passing through forests with rocky outcrops and thin, nutrient-poor soils. Its valleys provide habitat for species like wolf, lynx and woodland caribou.

Habitat loss and fragmentation are among the greatest threats to biological and genetic diversity, worldwide. Human activities like timber harvesting threaten the ability for the full diversity of plant life in an ecosystem to regenerate after impact. While we want and need some forestry, emerging science about conservation teaches us that if we want to preserve the variety of life in our homeland, we need to set areas aside from certain human activities that are known to harm ecosystems.