Hydrologic response of northern wetlands to silvicultural water management systems

摘要

Two types of water management systems are used to ameliorate saturated soil conditions which limit silvicultural operations and site productivity in northern wetlands. The pattern ditch system is an intensive drainage network designed to regulate water table depth in peat soils. The prescription drainage system is a low-intensity drainage system that is used to develop apparent drainage patterns in mineral and histic-mineral soils. These water management systems may either increase or decrease peak flow, base flow, and the duration of peak flow events, depending on drainage system design, climate, season, site characteristics, and land use. The most common hydrologic response to drainage is an increase in peak flow and base flow, and an increase in annual runoff. The effect of wetland drainage on watershed hydrology depends on the proportion of the watershed drained. Drainage may also affect water quality, nutrient cycling, vegetation composition and structure.