In November of 1998 four rural, forested plots were established at
Oregon Ridge Park in Baltimore County northeast of the Gwynns Falls
Watershed. Oregon Ridge Park contains Pond Branch, the forested
reference watershed for BES. Two of these four plots are located on
the top of a slope; the other two are located midway up the slope.
In June of 2010 measurements at the mid-slope sites on Pond Branch
were discontinued. Monuments and equipment remain at the two plots.
These plots were replaced with two lowland riparian plots; Oregon
upper riparian and Oregon lower riparian. Each riparian sites has four
5 cm by 1-2.5 meter depth slotted wells laid perpendicular to the
stream, four tension lysimeters at 10 cm depth, five time domain
reflectometry probes, and four trace gas flux chambers in the two
dominant microtopographic features of the riparian zones --- high
spots (hummocks) and low spots (hollows).
Four urban, forested plots were established in November 1998, two at
Leakin Park and two adjacent to Hillsdale Park in west Baltimore City
in the Gwynns Falls. One of the plots in Hillsdale Park was abandoned
in 2004 due to continued vandalism.
In May 1999 two grass, lawn plots were established at McDonogh School
in Baltimore County west of the city in the Gwynns Falls. One of these
plots is an extremely low intensity management area (mowed once or
twice a year) and one is in a low intensity management area (frequent
mowing, no fertilizer or herbicide use). In 2009, the McDonogh plots
were abandoned due to management changes at the school.
Two grass lawn plots were established on the campus of the University
of Maryland, Baltimore County (UMBC) in fall 2000. One of these plots
is in a medium intensity management area (frequent mowing, moderate
applications of fertilizer and herbicides) and one is in a high
intensity management area (frequent mowing, high applications of
fertilizer and herbicides).
Soil Moisture
Soil moisture is measured once every four to six weeks at each plot.
In each of the forested plots, five (six at Leakin plot #2) time
domain reflectometry waveguide probes from SoilMoisture Equipment
Corporation were installed vertically into the soil at random
locations throughout the plot. The waveguide probes are 20 cm long, so
those vertically installed span a depth of 0 to 20 cm below ground.
Each forested plot also has one (two at Leakin plot #2) set of four
waveguide probes installed horizontally into the soil in one location
at four depths: 10, 20, 30, and 50 cm below ground. The McDonogh plots
each have two sets of horizontal and no vertical waveguide probes.
Attached to each belowground waveguide is an aboveground cable with a
BNC Male Coaxial Fitting on the end. This fitting connects with
SoilMoisture's Trase System I (Model 6050X1, Version 2000 Software),
which uses time domain reflectometry (TDR) to measure soil moisture.
Every four to six weeks each individual vertical and horizontal
waveguide in each plot is connected to the portable Trase TDR
processor; soil moisture is measured instantaneously and stored in the
processor. After all plots are completed, the stored data is
downloaded onto a computer at the BES office at UMBC.
