Wednesday, July 8, 2015

“Whatcha doing there, Radha?” by Vincent Irizarry


While out in the field at Blackwater, we were looking for herbivory amongst our plots which consisted of non-vegetated and vegetated plots. These silver metal pieces were actually turned into homemade animal track plates using ethanol, mineral oil, and graphite powder. Radha, Taylor, Keryn, and I mixed the ethanol, oil, and graphite powder to create homemade ink. The ink was later spread across the tract plates and, these were later used in the field to see if animal activity was present.





Trimble Geo 7x: by Vincent S. Irizarry

The device that I am holding above is called a Trimble Geo7x. It is a Real Time Kinetic Global Positioning System (RTK GPS) device that connects to satellites around the world which relay a signal to the upper round disk in the photo. RTK systems can be used for a variety of field work purposes from documenting plant species in a programmed database, to photographing plant species, but most importantly the Trimble helps with spatial mapping. Under the guidance of Dr. Keryn Gedan I was able to survey a range of tidal marsh plots on the Blackwater Refuge area from previously forested lands that have now been cut (controlled) to our no vegetation/vegetation Control East & West sites. The Trimble RTK is capable of finding elevation of the lands in meters which precision as close to 1 centimeter.

“Why is it so important that you find the elevation of the lands in such precise measurements?”

In the beginning of our research project, we already started knowing that there was a high marsh elevation, a mid elevation, and a low elevation due to the changes in plant species and habitat, but the land is so flat that it is difficult to perceive these small differences in elevation. Under the supervision of Dr. Keryn Gedan I learned that although we can visually see the physical change in ecotone elevation, this proposal needs to be backed by actual numerical values. While using the Trimble RTK we acknowledged that on the Control Sites some of the numerical values did in fact correspond with what we expected but, in other areas where variation looked significant different the data showed the numerical values were less dramatic in change.

Monday, June 29, 2015

In the swamps, June 2015

By Vincent Irizarry, Radha Patel, and Taylor Howard

These loblolly pine trees reside on higher elevation marsh lands. As you navigate to lower lying areas, you can see where increased salinity has killed trees. (V.I)

Blackwater National Wildlife Refuge:
  • BNWR is a natural salt marsh area in Maryland that serves as a protective barrier for coastal communities and farmland throughout the region.
  • Storms and sea level rise associated with climate change has flooded communities and salt marshes in the eastern shore of Maryland near BNWR.
  • Marsh lands are migrating inland due to sea level rise and saltwater intrusion into the uplands is rapidly occurring. Lower elevation areas are most vulnerable.
  • The salinity of the marshes is impacting forests and farmlands. In the forests, this results in “ghost forests” with dead tree stumps, while in the farmlands, it results in killed crops.

Disturbed farmland. The brown area was sprayed to kill invasive Phragmites australis that enters areas where crops have been killed due to salinity. (V.I)

On the second day of our trip to the eastern shore, we toured local farm communities to observe the ecological damage. Within the last ten years alone 1,500 acres of farmland have been lost. Water running off of farms is high in nitrate and phosphorus due to fertilizer use. Nutrient rich water entering the Chesapeake Bay causes eutrophication, or poor water quality. In addition, in areas of high nutrients and disturbed soils, the invasive plant Phragmites australis grows. Phragmites is a weed that reduces salt marsh plant biodiversity and can be very difficult to get rid of. (V.I)

“But it’s just some grass, who cares?”

“We have plenty of other farms.”

As Phragmites continue to ravage the land, it takes up space that could be used for commodity crops that we all love such as corn, wheat, and soy. These lands are important not only to the local farm economy but to our national food security. Farmers within the area have entire livelihoods dependent on these lands. Many farmers are unwilling to give up these lands to government sponsored ecological succession programs.

Farms such as this one above produce high quantities of crops such as soy and corn. This farm has been exposed to salt water through flooding, as evidenced by the lack of crop growth near the edges of the plot. The likelihood of producing a quality yield is unknown.(V.I)

What would be produced on the farm.





During a part of another project, we collected water, grass, and soil samples for analysis. The water samples were tested by a small, portable analytical chemistry device to determine levels of Nitrate in the water near the farms. The FDA approves drinking water up to 10 units of Nitrate, yet many of these samples were in the 20s and 30s. Another intern in the lab is working on analyzing the soil and grass samples.