ABSTRACT: Snow accumulation and spring melt rates of bogs and fens in the North Granny Creek Catchment Basin, Hudson Bay Lowlands, Ontario.

CGRG Bibliography of Canadian Geomorphology
Search Results

Author :

Date :

Title :

Publication :

Issue :

Page(s) :

Abstract

The Hudson Bay Lowlands contain one of the most extensive, contiguous peatland complexes in the world. Interlinked patterned peatlands developed in this region because of the cool climate, low-gradient topography and an underlying layer of low conductivity marine sediments. There is currently little research regarding the mechanisms that control runoff and surface water connectivity in this region, especially the functions of different peatland types on runoff production and flow pathways. Runoff generation in these systems is dependent on several factors such as soil and pool storage capacity, snow accumulation and melt rates, and peatland morphometry. Snowmelt accounts for a major portion of total annual runoff in this region and the timing of the melt will determine effective runoff production from a peatland catchment. One of the objectives of this project is to identify the processes and mechanisms that generate spring snowmelt runoff in different peatland types (i.e. bogs and fens) and quantify the relative contribution of each type in a peatland-dominated catchment basin. This research is being conducted in a 30 km2 catchment basin located near the DeBeers Victor diamond mine, located 90 km west of Attawapiskat, Ontario. The North Granny Creek basin is located approximately 3 km from the mine pit and is comprised of several peatland types and forms. The surface hydrology of this area is expected to be affected by groundwater depressurization due to dewatering of the mine pit by deep groundwater pumping wells. Effects of this activity on surface hydrology could possibly include increased soil storage capacity due to drier conditions and decreased melt rates due to reduced inputs of warm groundwater. Surface water connectivity is usually at a maximum in the spring because of a relatively impermeable frost table and low soil storage capacity which reduces infiltration. These effects of melt will not be observed uniformly over the entire catchment because of the differing hydrological properties of peatland types. Fens are expected to experience melt quicker than bogs and will receive and convey most of the runoff waters. Snow survey data from the springs of 2008 and 2009 coupled with stream discharge measurements will be used to determine the characteristics of different peatland types that control snow accumulation, melt rates and runoff production and their respective contributions. Since it is expected that the surface hydrology of this area will change over time because of groundwater depressurization it is important to develop a base line characterization of runoff generation and flowpaths within and between peatland types. An examination of snow accumulation and melt characteristics is necessary in northern peatland complexes to fully understand the response of these environments to changes in hydrology.

Bibliography of Canadian Geomorphology