A specific concern is urbanization, which affects water quality by increasing its load of metals and organic contaminants. Template:Ref A study by Cook et al found an increase in mean annual runoff, instantaneous discharge, and hydrograph peak flow as a result of urbanization: " At least thirteen watersheds are linked to the Oak Ridges Moraine, and are managed by various organizations. In , Bigsby conducted the first investigation of the moraine. Template:Ref He noted the elevation, and styled the area Oak Ridge , identifying the portion of moraine north of Toronto.
It wasn't until Logan , in , that the moraine's extent was established to be between the Niagara Escarpment in the west, and the Trent River in the east. Taylor formally defined the landform as the Oak Ridges Moraine in He described its extent to be from King and Maple in the west to the Trent River in the east.
He also theorized that its origin was overlapping, interlobate glaciation retreat, between the Lake Ontario Lobe and the older Lake Simcoe Lobe.
This has become the accepted explanation for the moraine's development, though research in the s suggested the moraine may not be interlobate. Research conducted in the s reveals that the moraine has multiple origins: its eastern area has subglacial depositions Gorrell and McCrae, ; early parts of the moraine were deposited in an esker Brennand and Shaw, ; and that the moraine is not continuous, but is composed of multiple depositional environments: subglacial, ice-marginal and proglacial lacustrine Barnett et al, Main article: Politics of the Oak Ridges Moraine.
Although preservation of the moraine was first suggested in the s , it was not until that the issue achieved prominence in political discourse. The plan was completed in , but was subsequently dismissed in favour of local government administration of the affected lands.
This led to intense development on some portions of the moraine. In early , developers targeted Richmond Hill for large subdivisions on the moraine which would house over , people. A media campaign by environmental groups led to public opposition of the developments, and the issue was transferred to the Ontario Municipal Board OMB in By May , with the issue still unresolved, the provincial Conservative government announced a six-month moratorium on moraine development.
A panel was formed to create a land-use plan consistent with the current "smart growth" policy. The plan was released in October , and became the basis for the Oak Ridges Moraine Conservation Act , dividing the area into four zones with increasingly stringent controls on development in each. During the provincial election of , the Liberal Party of Ontario promised to terminate development on the moraine as part of their election campaign.
The government, in its attempt to halt developments, proposed the North Pickering Land Exchange. The complicated geological history which has led to the development of the Oak Ridges Moraine makes the landform what it is today. It ranges in width from 1 km to 15 km and has undulating topography made up of gravel, sand and some silt. The aquifer below the Moraine contributes to both local and regional ground water flows.
The varied geology of the Moraine has also contributed to the diversity of vegetation that can be found there. Fluvial involves the sediments motion and the erosion factors. Glaciolacustrine deposits are the components that come from the glaciers. It has been discovered that the Oak Ridges core is comprised of glaciofluvial areas.
The importance of the Oak Ridges Moraine was soon discovered and the Canadian government implemented steps to preserve it. This act came into being in Since then various organizations have formed in communities close to the region to help preserve this vital region of land.
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