P1259364602yLrWA

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Overview Assessing the Impact of Maneuver
Training on Nonpoint Source Pollution and Water
Quality (Project CP-1339) James M. Steichen1,
Phillip L. Barnes1, Stacy L. Hutchinson1, J.M.
Shawn Hutchinson2, Philip B. Woodford3,and
Naiqian Zhang1 1Department of Biological
Agricultural Engineering, and 2Department of
Geography, Kansas State University, Manhattan,
Kansas 66506 3Integrated Training Area
Management (ITAM), Fort Riley, Kansas 66442
Monitoring Sediment Concentration at Low-Water
Stream Crossings using an Optical Sediment
Sensor Naiqian Zhang1, Yali Zhang1, Wei Han1,
Quentin Stoll1, Darrell Oard1, James Steichen1,
Philip Woodford2, Philip Barnes1, and Stacy
Hutchinson11Department of Biological
Agricultural Engineering, Kansas State
University 2ITAM Program, Range Division, Fort
Riley Sediment concentration is defined as the
weight of suspended soil particles per unit
volume of water. Turbidity is usually referred to
as the optical properties of suspended/dissolved
materials in water on transmitting, reflecting,
absorbing, and scattering light. Thus,
traditional turbidity sensors are not
sediment-concentration sensors. A sediment sensor
developed in this study uses LEDs that emit
lights at three visible and infrared feature
wavelengths, which were selected through a
spectroscopic analysis, and light detectors
arranged at different angles from the light
sources. Statistical models established based on
test data allowed the sensor to be basically
insensitive to non-soil, suspended and dissolved
objects, such as algae, organic matter, and
various microorganisms, and less sensitive to
soil texture. A prototype sensor was tested at
combinations of four water types and five soil
textures in the laboratory. Statistical and
neural-network models successfully predicted
sediment concentration across samples of all the
combinations with R2 values of no lower than
0.95. An outdoor experiment proved that the
influence of ambient light on sediment
measurement can be largely eliminated by
modulating the lights. More than ten prototype
sensors of different designs have been fabricated
and calibrated. Several sensors were placed at
low-water crossings at Ft. Riley and Ft. Benning
for long-term, sediment-runoff monitoring. The
sensor case has been modified to improve its
waterproof capability. Difficulties encountered
during the long-term tests included signal
drifting and occultation of the optical lenses by
algae and soil particles. Modifications in
sensor and hardware/software have been made to
solve these problems. Work towards remote,
real-time monitoring and data storage through the
Internet is in progress. The system involves a
wireless sensor network that covers multiple
motes, which directly acquire data from the
sediment sensors, interface to a commercial
wireless telephone system, and a server on the
Internet.
A GIS-Enabled Kinematic Wave Approach for
Calculating the Transition between Sheet and
Concentrated Flows Stacy L. Hutchinson1, J.M.
Shawn Hutchinson2, and Ik-Jae Kim1 1Department of
Biological Agricultural Engineering and
2Department of Geography, Kansas State
University Non-point source (NPS) pollution has
been called the nations largest water quality
problem, and its reduction is a major challenge
facing our society today. As of 1998 over
290,000 miles of river, almost 7,900,000 acres of
lake and 12,500 square miles of estuaries failed
to meet water quality standards. Military
training maneuvers have the potential to
significantly alter land surfaces in a manner
that promotes NPS pollution, resulting in the
inability of military installations to meet water
quality standards and the decline of training
lands. Currently, most efforts to reduce NPS
pollution focus on the use of watershed water
quality models. Identification of overland flow
networks is a vital preprocessing step for these
NPS models. Flow networks are used to determine
transport routes for pollution and optimal
placement of best management practices. One
practice that is widely adopted for reducing NPS
pollution is the vegetated buffer system (VBS).
The primary hydrologic consideration for VBS
design and function is uniform sheet flow. With
time, however, overland flow concentrates and
channelizes, reducing contact time with
vegetation and NPS pollution reduction
efficiency. The kinematic wave approximation is
a useful technique for calculating overland flow
time of concentration within a drainage area.
Digital elevation models (DEMs) are widely used
for determining various landscape variables, as
well as for delineating overland flowpath
networks and drainage area boundaries. Using
topographic variables estimated from DEMs and
applying the kinematic wave theory in a GIS
environment, it is possible to estimate the
length and travel time of overland flow providing
an improved understanding of VBS placement for
maximum water quality benefit, as well as a
reduction in gully erosion caused by concentrated
flow.
Stream Crossings Effects on Streams at Fort
Riley Military Installation Gilbert Malinga1,
James Steichen1, Stacy Hutchinson1 ,Phillip
Woodford2 , Tim Keane3, and Amanda Pollock4
1Department of Biological Agricultural
Engineering, Kansas State University 2ITAM
Program, Range Division, Fort Riley 3Department
of Landscape Architecture/Regional and Community
Planning, Kansas State University 4Department
of Landscape Architecture, Kansas State
University Military maneuvers involve
effectively moving soldiers and equipment across
Fort Riley military installation training areas,
and this sometimes involves crossing streams.
Prior to 1992, the military randomly selected
where they would cross a stream or constructed
earthen fords to cross. During or after
high-flow events, both the randomly selected
sites and earthen fords posed a safety issue for
soldiers and equipment. Furthermore, use of the
randomly selected sites and earthen fords caused
tremendous degradation to the streams through
tearing of stream banks and generation of
excessive amounts of sediment, exceeding Total
Maximum Daily Load (TMDL) limits for water
quality downstream. In 1992, a Low Water Stream
Crossing (LWSC) project was initiated at Fort
Riley to address problems related to use of
earthen fords and randomly selected crossing
sites. New designs were developed. Selected
stream crossing sites were modified by hardening
stream beds and approach roads with rock and
gravel. By 2002, the LWSC project was generally
considered a success. Project achievements
realized were Provided safer training
conditions for military, improved access to
additional training areas, and alleviated some of
the environmental impacts related to crossing
streams. Design and construction of LWSC is
working well, but the major concern is site
selection for stream crossings. Riffles are best
locations for LWSCs, while pools, meander bends,
and tributary entry locations should be avoided.
Sediment transported from approach roads is
another major concern. Gravelling of roads, at
least up to 200 ft on either side of LWSC will
reduce amount of sediment detached from the
roads. Creation of water bars (built across
roads) to divert storm runoff to riparian
management zones will reduce amount of sediment
from upland areas delivered through approach
roads into the streams.
The Effects of Different Resolution DEMs in
Determining Overland Flow Regimes Stacy L.
Hutchinson1, J.M. Shawn Hutchinson2, Ik-Jae Kim1,
and Philip Woodford31Department of Biological
Agricultural Engineering, Kansas State
University 2Department of Geography, Kansas
State University 3ITAM Program, Range Division,
Fort Riley A gully head is a unique landscape
feature where concentrated overland flow begins
to cause significant erosion. The impacts of four
different resolution digital elevation models
(DEMs), three (3, 10, and 30 m) developed using a
differential global positioning system (GPS)
survey and the USGS 30 m DEM, were used to
identify transitional flow areas on a grassland
hillslope. A simple erosion model, nLS, based on
Mannings kinematic wave theory, was used to
determine where overland flow transitioned from
sheet flow to concentrated flow. The accumulated
erosive energy was estimated using the nLS model,
where, n is Mannings coefficient, L is the
overland flow length, and S is the slope. In
addition to the DEMs, spatial analyses for soil
(SSURGO) and land cover (Kansas GAP) were
conducted in a geographic information system
(GIS). First order streams were delineated using
each resolution DEM (contributing area 900 m2)
and overlaid with the concentrated flow data
obtained from the nLS model results. The
intersected area was buffered by 3, 6, 10, or 15
m, depending on the DEM resolution. Results
showed that average topographic and hydrologic
variables varied between the different DEM
resolutions. The 3 m DEM produced the best model
accuracy, predicting two gully head locations.
The recommended buffer radius was found to be 6
m, which is 2 times of the grid size. The efforts
to develop finer data resolution should be
supported in assessing reliable erosion potential
for watershed management.
Effects of Microtopography and Vegetation Growth
on Nonpoint Source Pollution Control in Tallgrass
Buffers Stacy L. Hutchinson1, Ik-Jae Kim1, Philip
Woodford2, Monte Cales3, Philip L. Barnes1, and
Amy K. Good11Department of Biological and
Agricultural Engineering, Kansas State
University 2Integrated Training Area Management,
Fort Riley 3USDA-NRCS Vegetated buffer systems
(VBS) are considered one of the most sustainable
BMPs for mitigating NPS pollution. In this study,
the efficiency of tallgrass VBS was evaluated on
3-meter by 20-meter tallgrass buffers during the
summer and early fall. Using data collected with
double-ring infiltrometers, infiltration rates
were estimated by the Green-Ampt approximation
(GA). Three vegetation parameters, canopy height,
dry biomass, and photosynthetically active
radiation (PAR) over leaf area, were monitored
during the period of study to assess the impact
of vegetation development on runoff generation
and transport. A 60-cm and 100-cm resolution
digital elevation model (DEMs) were developed
using a total station survey to investigate the
impact of slope variation and flow length on time
of concentration for overland flow using
Mannings kinematic equation and the
Darcy-Weisbach equation. The VBS trapping
efficiency was 99 of TSS, 97 of T-N, 88 of
T-P, and 87 of PO4--P on average. While
infiltration was overestimated in August, the
difference between estimated infiltration from GA
and calculated infiltration using a water balance
significantly decreased in October as vegetation
senesced. Switch grass (Panicum virgatum) growth
averaged 7.0 mm/day between August and early
September and declined to 0.9 mm/day between
September and early October. Vegetation clipping
did not influence the runoff ratio or water
quality, indicating that upper vegetation canopy
does not retain significant water. The higher
resolution DEM (DEM60) showed more detailed slope
variation and flow direction, particularly for
smoother buffer topography. Mannings kinematic
estimation yielded more accurate times of
concentration than the Darcy-Weibach estimation.
Spatial and Temporal Analysis of Soil Moisture
using MODIS NDVI and LST Products J.M. Shawn
Hutchinson1, Thomas J. Vought1, and Stacy L.
Hutchinson21Department of Geography and
2Department of Biological Agricultural
Engineering, Kansas State University Soil
moisture is an important input for hydrologic and
climate models but often exhibits significant
spatial and temporal variation. The water content
of soils affects a variety of physical and
biological processes in the biosphere and links
the Earth's surface and atmosphere through its
influence on surface energy and moisture fluxes.
In addition, antecedent soil moisture conditions
affect the hydrologic behavior of land surfaces
by controlling, in part, the infiltratration
capacity of soils and the partioning of
precipitation into runoff and storage terms. This
study uses normalized difference vegetation index
(NDVI) and land surface temperature (LST) data,
acquired by the Moderate Resolution Imaging
Spectrometer (MODIS), in a linear regression
model to predict volumetric water content (VWC)
of near surface soils for Fort Riley. the
northeastern Kansas to estimate regional soil
moisture levels. These estimates will be used to
evaluate antecedent soil moisture conditions and
used as input into a landscape-scale surface
water quality model to evaluate the effectiveness
of riparian buffers in filtering sediments
transported from upland sites within mechanized
military training areas. A strong negative
relationship exists between surface temperature
and greenness for different biomes, which can be
used as a landscape-level proxy for surface
wetness. Near real time MODIS satellite data
products were obtained from the EOS Data Gateway.
Land surface temperature and NDVI data is in the
form of 8-day and 16-day maximum value
composites, respectively, at a spatial resolution
of 1 kilometer. Soil moisture was measured
weekly at 80 control points using a portable
time-domain reflectometer (TDR). Using a
geographic information system (GIS), LST, NDVI,
and TDR points were overlaid to create a table of
values that could be input into a linear
regression model to that could be inverted to
predict soil moisture content based upon NDVI and
LST image data alone. Early results are
promising as the amount of variation in measured
soil moisture explained by MODIS LST and NDVI
image bands was strong, especially considering
image grain. Daily estimates of soil moisture
with an approximate standard of 9 have been
produced.