Photo: Norm Legault
Biological Diversity
Biological diversity, or biodiversity, is often thought of as the combination of animals, plants, insects and other micro-organisms that make up an ecosystem. Though this variety of species is important to biodiversity, the concept extends much further and incorporates also the genetic differences between species, varieties in ecosystems and all of the systematic interconnections that make our Earth a whole. Or, in other words, it is the web of life and the holistic patterns that form from it. This coordination of nature is what provides many of the goods and services that we need to survive and maintain a quality of life.
Biodiversity offers us resources that we extract and later process to make material goods. Much of modern medicine derives from plants, as well as our agriculture. And many natural elements are referred to in cultural, spiritual and aesthetic processes to represent our connection with nature - such as using flower patterns on clothing, or the wolf symbolizing courage, strength and loyalty to many First Nations. Biological diversity is the foundation upon which we build our industries, fuel our economies, and stimulate our societies.
Biological Diversity Under Threat
Rivers, creeks and ravines link habitat fragments. Larch Sanctuary is a 59 acre sanctuary that’s part of the larger Edmonton river valley network, which serves as a “highway” for wildlife in our region.
A strong ecosystem supports all sorts of species, which, in turn, generate a balanced and fruitful habitat. The greatest risk to this biodiversity is the loss, degradation, and fragmentation of habitat. Fragmentation refers to the division of an ecosystem into smaller and isolated fragments. Once an ecosystem is fragmented, each portion exists independently within a background ecological system termed the “matrix”, which is typically utilized for human purposes such as agriculture or urban development. An example of this is clear cutting large portions of a forest to make room for growing crops. The remaining sections of forest would become smaller, less diverse areas of habitat, separated and suspended within a matrix of agriculture. Now the interior of that habitat is exposed to different conditions, which can change the levels of light, humidity and temperature and affect the organisms living there. This is known as the edge effect. Now that their home can no longer support them as well, animals may leave. For those who choose to stay, they risk interbreeding and are more susceptible to invasive species and predation.
Corridors, Buffers and Stepping Stones
Imagine fragmented habitat as islands amidst a sea of urbanized or industrialized territory. These islands are all different sizes, can be connected, and can serve different purposes to animals. Some islands can be patches for wildlife, which means that a species can fulfill all or part of its life cycle in that one specific fragment. Other islands are stepping stones for migratory animals, offering a place of refuge within the matrix as they make their way to larger, undisturbed habitats. A snail, for example, could live its entire life in only one patch because it would have enough resources to survive. A bear, on the other hand, has a large range of territory and much higher demands for food and shelter, so this patch would only be a stepping stone with temporary resources. These patches and stepping stones can be linked together by corridors, a landscape element that enables movement between patches. Corridors can be anything from a tree or hedge row to a river edge (the Edmonton river valley is a vital corridor in our area). Terrain that is around patches and fragments create buffer zones, which help ease the edge effect on fragmented ecosystems, reducing outside conditions on the newly exposed habitats. For example, a stretch of shrub land along the borders of a newly exposed forest fragment protects the interior from conditions not typical of its existence.
By Dorothy Monteith
Why is Conservation Important?
A Walk in the Woods by Roxanne Hastings at Boisvert Conservation Land. Boisvert is 80 acres of old growth forest situated north of Edmonton. It serves as a stepping stone for wildlife and a haven for native plant species.
Conserving natural ecosystems is central to protecting biodiversity. In fact, it is one of the most crucial strategies to reduce harmful effects of habitat destruction. Protected lands act as stepping stones, corridors and permanent habitats for plants, animals and microorganisms so that they can thrive in their natural state. Our landscape continues to change as a result of human impact and climate change and it becomes increasingly important to secure and safeguard areas of ecological significance. EALT works to create a network of protected areas so that wildlife can move freely through our matrix despite these pressures.
Sources:
Secretariat of the Convention on Biological Diversity. (April, 2000). Sustaining Life on Earth. Retrieved from: https://www.cbd.int/convention/guide/?id=web
Resasco, J., Bruna, M.E., Haddad, N.M., Banks-Leite, C., & Margules, C.R. (2017, January 01). The Contribution of Theory and Experiments to Conservation in Fragmented Landscapes. Retrieved from: https://onlinelibrary-wiley-com.ezproxy.macewan.ca/doi/full/10.1111/ecog.02546
Bennet, A.F., & Saunders, D.A. (2010). Habitat fragmentation and Landscape Change. In Sodhi, N.S., & Ehrlich, P.R (Ed.), Conservation Biology for All. Retrieved from: https://books.google.ca/books?hl=en&lr=&id=bCiQDwAAQBAJ&oi=fnd&pg=PA88&dq=land+fragmentation+and+conservation&ots=gf7D__u641&sig=xdqj_AiKxguZ3ZBcWhFZ2fuDWpI#v=onepage&q=land%20fragmentation%20and%20conservation&f=false
Trees for Life. Habitat Fragmentation (n.d.). Retrieved from: https://treesforlife.org.uk/into-the-forest/habitats-and-ecology/human-impacts/habitat-fragmentation/
Lindenmayer, D., & Fischer, J. (2006). Habitat Fragmentation and Landscape Change: An Ecological and Conservation Synthesis. Retrieved from: https://ebookcentral-proquest-com.ezproxy.macewan.ca/lib/macewan-ebooks/detail.action?docID=3317424
Sykes, A.K., & Hannon, S.J. (2001). Fencerows as Habitat for Birds in an Agricultural Landscape in Central Alberta, Canada. Retrieved from: https://www-tandfonline-com.ezproxy.macewan.ca/doi/abs/10.1080/11956860.2001.11682673