Search

Search Results

• 1. [Article] Development of baseline data on Oregon's high desert vernal pools

  Vernal pools are ephemeral surface water wetlands with unique hydrology, ecology and species composition. Rare and endemic species rely on vernal pool habitat due to specialization traits the species possess ...

  Citation × Citation Citation Abstract Copy Title: Development of baseline data on Oregon's high desert vernal pools Author: Wyland, Sara Alice Vernal pools are ephemeral surface water wetlands with unique hydrology, ecology and species composition. Rare and endemic species rely on vernal pool habitat due to specialization traits the species possess because they are adapted to the extreme conditions. Many vernal pool basins have been topographically and hydrologically altered and are utilized heavily for cattle, which can lead to deleterious effects to vernal pool ecosystems. Little research has been performed on Oregon's high desert vernal pools, impeding proper management and protection. This study was conducted to gather baseline data on the pools over the 2011 and 2012 spring to fall seasons. Water quality analysis was performed to determine if differences exist between natural vernal pools, those that have been altered, and anthropogenic water source alternatives in the region, and to see if water chemistry changes as the pools dry down. Some trends were shown, but the data were highly variable within site classifications. General temporal trends of pools showed increases in temperature, turbidity, conductivity and anions, and decreases in dissolved oxygen and oxidation-reduction potential throughout the seasons. Natural pools displayed opposite temporal trends of turbidity and nitrate than other site types, indicating different chemical functioning. Excavations inside basins where water was only present in the excavation had different water chemistry from excavations where water was overflowing into the natural basin, and from unaltered natural basins, demonstrating impacts of excavated topography. Although some patterns can be recognized, the data was variable and suggest little can be assumed about the water quality status of Oregon’s high desert vernal pools. A GIS and remote sensing method was developed to quantify the change in water surface area in the high desert at various time points by performing supervised classifications of SPOT images. The method was found to be capable of easily deriving surface areas from the SPOT images, with little potential for error. Water surface areas were extracted from ten SPOT images taken from 2010 to 2013. Surface areas were compared to local climate data to assess for determining factors. The temporal resolution of the preliminary analysis was not high enough to determine causation, but results suggest annual precipitation and timing persistence are important factors in water surface areas. Title: Development of baseline data on Oregon's high desert vernal pools Author: Wyland, Sara Alice Vernal pools are ephemeral surface water wetlands with unique hydrology, ecology and species composition. Rare and endemic species rely on vernal pool habitat due to specialization traits the species possess because they are adapted to the extreme conditions. Many vernal pool basins have been topographically and hydrologically altered and are utilized heavily for cattle, which can lead to deleterious effects to vernal pool ecosystems. Little research has been performed on Oregon's high desert vernal pools, impeding proper management and protection. This study was conducted to gather baseline data on the pools over the 2011 and 2012 spring to fall seasons. Water quality analysis was performed to determine if differences exist between natural vernal pools, those that have been altered, and anthropogenic water source alternatives in the region, and to see if water chemistry changes as the pools dry down. Some trends were shown, but the data were highly variable within site classifications. General temporal trends of pools showed increases in temperature, turbidity, conductivity and anions, and decreases in dissolved oxygen and oxidation-reduction potential throughout the seasons. Natural pools displayed opposite temporal trends of turbidity and nitrate than other site types, indicating different chemical functioning. Excavations inside basins where water was only present in the excavation had different water chemistry from excavations where water was overflowing into the natural basin, and from unaltered natural basins, demonstrating impacts of excavated topography. Although some patterns can be recognized, the data was variable and suggest little can be assumed about the water quality status of Oregon’s high desert vernal pools. A GIS and remote sensing method was developed to quantify the change in water surface area in the high desert at various time points by performing supervised classifications of SPOT images. The method was found to be capable of easily deriving surface areas from the SPOT images, with little potential for error. Water surface areas were extracted from ten SPOT images taken from 2010 to 2013. Surface areas were compared to local climate data to assess for determining factors. The temporal resolution of the preliminary analysis was not high enough to determine causation, but results suggest annual precipitation and timing persistence are important factors in water surface areas. Close