Tuesday, November 9, 2010

Human impact on Nose Hill Park: Alice and Curtis.

            Nose Hill Park in our opinion is such a great place- it provides an area where animals, insects and plants can establish their own natural community within Calgary’s urban community. We think that Nose Hill is a very valuable gift that citizens of Calgary over time have fought to give to the animal, insect and plant species that have been displaced from the never-ending construction and urban development of Calgary’s increasing population. However, Nose Hill park is a public park and citizens of Calgary love to go into the park to bike, take walks, walk their dogs, or to just enjoy the natural scenery. Or if people are students, teachers, or scientists, we like to step into this park to investigate its ecology like what we just did a couple weeks ago. This leads to a question: how has human use of this park affected the organisms and ecology of the park?
            There are many negative affects of human use of the park that we have researched all of the following information was found in Biophysical Impact assessment (2006). First of all, trails and informal walk-ways have been constructed and developed all throughout Nose Hill for human users. These trails affect many things. By building trails, strips of habitats will be lost; organisms and animals will be displaced- losing their feeding, reproduction, shelter or living grounds.
Trails also result in what’s called habitat fragmentation: what was before a large piece of land is separated into smaller pieces by intersecting trails. This will lead to smaller communities in a smaller area- this smaller community is then more prone to extinction in that small area. Habitat fragmentation also inhibits certain species from movimg across the trail barriers to other pieces of habitat.  This reduces habitat availability for these less mobile organisms.
            Another issue is the constant trampling in the grasslands by people and dogs. It has been researched that the dominant grass species of Nose Hill- Rough Fescue grass- is very sensitive and susceptible to trampling. Trampling can do many negative things to the grassland. Firstly, it compacts the soil more which reduces the amount of air and water that seep through the more compacted pores in the soil. This results in decreased plant growth because the plant roots cannot grow down into the compacted soil. This also leads to more of soil erosion after rainfalls/snowfalls. Secondly, these trampled areas start to undergo a succession process which usually involves more un-natural weed-like species inhabiting the disturbed area (especially along trail-sides). This will cause increased competition between the natural species and the weed species that are usually the more competent ones.
Trampling will cause physical damage to the leaves, stems and roots of plants which will inhibit the plants’ ability to grow and mature.
As well, trampling results in certain bird species’ nests to be damaged and damaging other organisms’ nesting/den grounds.
            Finally, another big human impact issue in the grassland of Nose Hill are dogs. Dogs love to chase around small mammals in the park such as rabbits and Richardson’s ground squirrels. Not only will this cause distress to these rabbits and ground squirrels, but the dogs may attack them and kill them.
            All of these are the three main issues of human impacts on the grassland area of this park. However unlike most cities, Calgary is fortunate to have kept this large expanse of natural environment; even though there are some serious ecological issues by human use of the park, the organisms that inhabit the park are more fortunate than other organisms. There are government planners that do keep in mind of these bad human impacts and bring up suggestions to fix these issues. The question is - is there such thing as a perfect natural protected park where organisms can dwell in such an expanding and populated city? Is there only so much we can do to protect Nose Hill from urban sprawl? These questions are hard to answer but hopefully we will find the answers through continuous research and love of this wonderful park. 

Biophysical Impact assessment. (2006). http://www.calgary.ca/docgallery/bu/parks_operations/nosehill/nh_bia.pdf). Retrieved October. 26, 2010,

Monday, November 8, 2010

Autumn 4: Leaves

Autumn 4. The Leaves
            In the part of the world I call Home, leaves of broad leafed, or deciduous, trees respond to shortened day length by changing colour from green to red, orange or yellow.  Aspen and Maple, Birch and Elm spread colour to the winds, signaling the beginning of the season when plants and animals prepare for winter; Autumn.  Many here call this season “Fall”, perhaps remembering this is what leaves do after their colour is changed by trees.  Leaves cover the roadways and sidewalks, parks and lawns, dancing in the wind and collecting in bright crunchy piles wherever the wind chooses to pile leaves.
Figure 1.  Autumn leaves on the forest floor.  Photo by TP.
            My neighbours do not like leaves.  They invest time and effort blowing leaves off sidewalk and driveway; raking leaves off lawns.  Leaves fill giant plastic bags, and bags decorate sidewalks until those in charge of bags for the city in which I live come and take them.  Leaves look better without bags.  And the wind blows the leaves, and the leaves dance.  Leaves like my neighbour’s lawns, satisfying my neighbours need to blow and rake.
            I like leaves.  I invest time and effort walking through leaves, kicking them into the air, revelling in the flash of colour and the sound of crunch.  I like Ladybird beetles, and Ladybird beetles like leaves.  Deep under the soft insulating leaves, where the cold never reaches, all through our long white winter, Ladybird beetles sleep.  I know leaves guard Ladybirds, so my leaves stay where the wind would have them.  Who would argue with the wind?
            What of the leaves that Aspen turn yellow in the forest of my park?  No doubt some dance into my neighbour’s rakes.  Some fly into the grassland at the whimsy of the wind.  When I look for leaves, I find most lying on the forest floor, patches of yellow on brown and red.  Last years leaves lie beneath, hinting of what happens to Aspen leaves as autumn turns into winter, and winter into spring.  Frail and thin, brown soggy parchment leaves slowly disappear, vane first, leaving delicate networks of vein and rib.  In time, vein and rib, too, follow vane into soil.  Hidden life thrives in turning leaf to soil.  This life, so often ignored, releases carbon and nitrogen, phosphate and mineral.  Leaf becomes soil and soil nourishes forest, ensuring Aspen will set new leaves come snow melt and spring.  Aspen teaches about Aspen, leaf slowly becomes leaf, nutrients cycle, and all is well with my forest.