FIELD TEST OF COMPOST AMENDMENT TO REDUCE NUTRIENT
RUNOFF
FINAL REPORT
prepared by:
Robert B. Harrison
Mark A. Grey
Charles L. Henry
Dongsen Xue
UNIVERSITY OF WASHINGTON
COLLEGE OF
FOREST
RESOURCES
Ecosystem Science and
Conservation Division
Box 352100
Seattle WA 98195
206 685 7463 voice
206 685 3091 FAX
May 30, 1997
prepared for:
Phil Cohen
Effect of Compost on P Runoff Final Report
City of Redmond
Public Works
Redmond, WA 98052
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Effect of Compost on P Runoff Final Report
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TABLE OF CONTENTS
TABLE OF CONTENTS ............................................................................................................... 3
EXECUTIVE SUMMARY ............................................................................................................ 4
INTRODUCTION AND PROJECT OVERVIEW...................................................................... 5
SITE, METHODS AND MATERIALS ........................................................................................ 6
Site Description and Construction ....................................................................................... 6
Soil and Compost Analysis .................................................................................................... 6
Plot Establishment and Fertilization .................................................................................... 7
Storm Simulation ................................................................................................................... 8
Runoff Characterization and Collection .............................................................................. 8
Runoff Analysis ...................................................................................................................... 8
RESULTS AND DISCUSSION ..................................................................................................... 9
Soil and Compost Analysis .................................................................................................... 9
Storm Hydrology .................................................................................................................. 10
Water Chemistry .................................................................................................................. 10
Hydrology and Water Chemistry Assimilation ................................................................. 13
SUMMARY AND CONCLUSIONS ........................................................................................... 16
Summary of Results ............................................................................................................. 16
Implications of Results ........................................................................................................ 17
Future Directions ................................................................................................................. 18
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EXECUTIVE SUMMARY
This project looked at the use of compost as an amendment to Alderwood series soil to
increase water-holding capacity, reduce peak flow runoff, and decrease phosphorus in runoff.
Seven 8 ft. x 32 ft. beds were constructed out of plywood lined with plastic and filled with
Alderwood subsoil or mixtures of soil and compost. These beds were located at the College of
Forest Resources Center for Urban Horticulture at the University of Washington. Samples were
taken over the period from March 7 to June 9, 1995. Compost amendment had the following
effects on physical water properties:
* Water-holding capacity was about doubled with a 2:1 compost:soil amendment.
* Water runoff properties were improved with the compost amendment, with the compostamended soil showing greater lag time to peak flow at the initiation of a rainfall event and
greater base flow in the interval following a rainfall event.
Water chemistry (total P, soluble-reactive P and nitrate-N) was measured for a series of
artificial and natural rainfall events. For the overall study, which included fertilizer treatments, the
following results were observed:
 Runoff from the compost-amended soil had 24% lower average total P concentration (2.05 vs.
2.54 mg/L) compared to the Alderwood soil that did not receive compost amendment.
 Soluble-reactive P was 9% lower in the compost-amended soil (1.09 vs 1.19 mg/L) compared
to the Alderwood soil that did not receive compost amendment.
 Nitrate-N was 17% higher in the compost-amended soil (1.68 vs 1.39 mg/L) compared to the
Alderwood soil that did not receive compost amendment.
The water flow data from several storm events was coupled with the nutrient concentration
data to generate fluxes of nutrients from the plots. Results of these studys were variable, with
compost-amended soils lower in total P runof than unamended. When totals of fluxes are
summed, the compost-amended soils showed the following:
* 70% less total P,
* 58% less soluble-reactive P and
* 7% less nitrate in runoff compared to runoff from the till-only soil.
Differences in fluxes were attributed more to the changes in water flux rates than to water
chemistry, but both accounted for the lowered P with compost amentment. The results of this
study point out the promise of the use of organic amendments for improving water-holding
capacity, runoff properties and runoff water quality of Alderwood soils converted to turfgrass
from future development. The variability of results indicate a need for larger-scale field
confirmation (with replicated plots) of the results from these constructed research plots. Ideally,
any future study would include a turf established with other common commercially-utilized
methods, such as the practice of placing sod directly onto glacial till soil.
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INTRODUCTION AND PROJECT OVERVIEW
The College of Forest Resources (CFR) examined the effectiveness of using compost as a soil
amendment to increase surface water infiltration to reduce the quantity and/or intensity of surface
and subsurface runoff from land development projects. In addition compost amendment was
evaluated for its ability to reduce the transport of dissolved or suspended phosphorous (P) and
nitrogen (NO3) from drainage waters for the City of Redmond. The goal was to evaluate options
for improving the quality of water reaching Lake Samammish, Bear Creek and the Sammamish
River. Currently, due to the wide distribution and inherent stability of till soils in the region, most
residential housing developments are sited on the Alderwood soil series, which is characterized by
a compacted subsurface layer that restricts vertical water flow. When disturbed (and particularly
when disturbed with cut and fill techniques as with residential or commercial development),
uneven water flow patterns develop due to restricted permeability. This horizontal flow of water
on the surface and subsurface contributes to excessive overland flow, especially during storm
events, and transport of dissolved and suspended particulates to surface waters.
Research has demonstrated compost's effectiveness in improving the soil physical properties
of porosity, continuity of macropores, and water holding capacity which directly influence soilwater relationships. It is clear that compost's chemical properties can also be valuable in some
cases, such as in complexing potentially harmful trace metals including copper, lead, and zinc.
Under this premise, the CFR examined the effectiveness of using compost to increase stormwater
infiltration and water holding capacity of these glacial till soils. Additionally, the CFR examined
whether or not increasing the infiltrative and retentive capacity of glacial till soils (Alderwood
series) can increase the contact with and retention of P and N by soil absorptive mechanisms, and
the production of P and N in surface and subsurface runoff by unamended and amended soils
during rainfall events.
The CFR utilized the existing Urban Water Resource Center (UWRC ) project site at the
University of Washington's Center for Urban Horticulture (CUH) for conducting the study. The
CFR utilized the UWRC design of large plywood beds for containing soil and soil-compost
mixes. These beds were located at the College of Forest Resources Center for Urban Horticulture
at the University of Washington. Water was supplied from a nearby existing water supply system
and used to simulate actual rainfall conditions. Simulated rainfall events of varying intensity were
scheduled to characterize infiltration rate, quantity of water flowing overland and subsurface,
quantity of water leaving study plots, and water quality leaving study plots. Samples were taken
over the period from March 7 to June 9, 1995.
The following paper describes the site, methods, results, and potential implications of these
studies.
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SITE, METHODS AND MATERIALS
Site Description and Construction
What was done. Working with the UWRC, the CFR utilized the existing site and associated
facilities at the University of Washington CUH. The system includes two different (different
sites) Alderwood till soils that were transported to the site, and several mixtures of the till soils
and compost mixtures readily available in the Seattle area. These mixtures include two control till
soils, a 2:1, 3:1 and 4:1 mixture (soil:compost by volume) of Cedar Grove fine compost:till soil, a
2:1 Cedar Grove coarse compost:till soil mixture, and a 2:1 GroCo compost:till soil mixture.
Figure M-1 shows the plot layout and treatments for the site. The soil and compost for this
study was mixed on an asphalt surface with a bucket loader and hauled and dumped into the plot
bays. The UWRC built the bays and installed the sprinkler and water monitoring system. A
system of collection buckets to allow sampling of runoff at intervals ranging from 15 minutes to
longer was installed as well.
Soil and Compost Analysis
Soil and soil/compost mixture samples were analyzed by the CFR analytical labs for the
following parameters:
1) total C,
2) total N,
6) bulk density,
7) particle density,
3) gravimetric water holding capacity (field capacity) moisture,
4) volumetric water holding capacity (field capacity) moisture,
5) total porosity,
8) particle size analysis, and
9) soil structure.
Samples were collected in August, 1994 from plot 1 (unamended Alderwood soil 1) and plot 2
(2:1 Cedar Grove fine compost:Alderwood soil 1). Analysis results are located in Appendix
Table 1a. These were characterized for all of the above properties. Samples were also collected in
December, 1994, but due to extremely wet conditions, it was not always possible to characterize
samples for all of the above properties.
Total C and N were determined using an automated CHN analyzer since they were considered
to be the primary measures of soil productivity in these soils. Bulk density was estimated using a
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coring device of known volume (bulk density soil sampler). The core was removed, oven dried,
and weighed. Bulk density was calculated as the oven dry weight divided by the core volume.
Particle density was determined by using a gravimetric displacement. A known weight of soil or
soil/compost mixture was placed in a volumetric flask containing water. The volume of
displacement was measured and Particle density calculated by dividing the oven dry weight by
displaced volume.
Gravimetric water holding capacity was determined using a soil column extraction method
that approximates field capacity by drawing air downward through a soil column. Soil or
soil/compost mixture was placed into 50 ml syringe tubes and tapped down (not compressed
directly) to achieve the same bulk density as the field bulk density measured with coring devices.
The column was saturated by drawing 50 ml of water through the soil column, then brought to
approximate field capacity by drawing 50 ml of air through the soil or soil/compost column.
Volumetric water holding capacity was calculated by multiplying gravimetric field capacity by
the bulk density. Total porosity was calculated by using the following function:
bulk density
total porosity = 1-( particle density ) x 100%
(eq. 1)
Particle size distribution was determined both by sieve analysis and sedimentation analysis for
particles less than 0.5 mm in size. Due to the light nature of the organic matter amendment,
particle size analysis was sometimes difficult, and possibly slightly inaccurate. Soil structure was
determined using the feel method and comparing soil and soil/compost mixture samples to known
structures.
Plot Establishment and Fertilization
Plots were planted to a commercial turfgrass mixture during the Spring, 1994 season.
Fertilizer was added to all plots during plot establishment in the Spring of 1994 (16-4-8 N-P2O5K2O) broadcast spread over the study bays at the rate recommended on the product label (0.005 lb
fertilizer/ft2). The initial application resulted in an application of 0.023 lb of elemental P as
orthophosphate per plot or 0.000087 lb P/ft2. This resulted in an application of 0.20 lb of
elemental N as ammonium and nitrate (undetermined distribution) per plot or 0.00080 lb N/ft2.
Due to the poor growth of the control plots, and in order to simulate what would have likely
been done anyway on a typical residential lawn, an additional application of 0.005 lb/ft2 was made
to control plots on May 25, 1995. This helped to establish grass over a larger proportion of the
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surface, which was quite bare. The compost-amended plots never appeared to need fertilizer
following establishment, and thus fertilization wasn't necessary to establish turfgrass.
Storm Simulation
Both surface and subsurface runoff were collected following seven simulated rainfall events.
To create uniform antecedent runoff conditions, some storm events were quickly followed by
another event. Simulated rainfall was applied at total amounts ranging from 0.76 to 2.46 inches
equivalent per storm, and rates ranging from 0.29 to 0.63 in/hour (Table M-1). The total amounts
and rates of rainfall during artificial events was estimated by placing collection tins across and
along the length of the plots. The amounts of water in the tins was measured at regular intervals
during plot irrigation.
Runoff Characterization and Collection
Runoff amounts and rates were measured for 15 minute intervals by use of tipping bucket type
devices attached to an electronic recorder. Each tip of the bucket was calibrated for each site and
checked on a regular basis to give rates of surface and subsurface runoff from all plots. There
appears to have been some movement of surface flow along the junction between the plot
containers and soil or soil/compost during heavy surface flow events, particularly for the soil-only
plots. There were also several instances where tipping buckets stuck during high rates of water
flow. These were fairly easily noted visually and by the data on the recorder (Table M-1).
Runoff was collected from bucket tips during 36 separate intervals by placing a collection
bucket at the base of the tipping bucket during each simulated rainfall event. Anywhere from 1 to
7 samples were taken for each storm event with intervals ranging from 15 minutes to 191 hours
(Table M-2).
Runoff Analysis
Runoff was analyzed by the CFR analytical laboratory for the following chemical species:
1) Soluble-reactive P (SRP),
2) Acid-hydrolyzeable phosphorus (AHP)
3) total Phosphorus (TP),
4) soluble nitrate (NO3)
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All work was done in accordance with University of Washington analytical laboratory QA/QC
procedures.
RESULTS AND DISCUSSION
Soil and Compost Analysis
The total C, total N, bulk density, particle density, gravimetric water holding capacity (field
capacity) moisture, volumetric water holding capacity (field capacity) moisture, total porosity,
particle size analysis, and soil structure of Alderwood soil and soil/compost mixtures is given in
Appendix 1 for the August, 1994 and December, 1994 samplings. Results show large changes in
the chemistry and physical properties of the soil/compost mixtures due to the compost amendment
(Appendix 1a, Appendix 1b).
The terminology used in industry and science for compost and soil properties is somewhat
inconsistent, so it will be explained quickly how calculations were made. First, percentages can be
given as % by weight or % by volume. In this report, percent by weight uses an oven-dried basis
for calculation. Volumes can change depending on handling, storage, moisture content and other
factors. As a final note the density (volume per unit weight) for compost is usually much lower
(i.e. 0.2-0.3 g/cm3) than for soil (i.e. 1.0-1.4 g/cm3), so a weight percent change from compost
amendment will usually be much lower than a volume unit change, and moisture capacity based
on volume may be much different than moisture capacity based on weight.
Total C and organic matter was enhanced, increasing from 0.2-0.3% C (0.3-0.5% organic
matter) to about 2.4-2.8% C by weight (4.1-4.8% organic matter) with the compost amendment.
Total N was also enhanced, increasing from 0.04-0.12% to about 0.17-0.27% with the compost
amendment. Gravimetric field moisture capacity increased significantly from 19-29% to 35%
with the compost amendment. Volumetric field moisture capacity was also increased from 24 to
37% by the addition of compost.
Total porosity was increased from 19 to 39%. It appears that the measurement of porosity
might have been poor for the unamended sites, since this is extremely low for a soil. Bulk
density was decreased from about 1.3-1.9 to 1.1-1.3 g/cm3. Particle density was decreased from
about 2.3-2.5 to 2.0-2.1 g/cm3. Particle size analysis was not greatly affected by the compost
amendment. Soil structure, which is not a quantitative property, was also not greatly affected by
compost amendment.
Thus, there was a generally beneficial effect of the compost amendment in regards to nutrient
content as well as soil physical properties known to affect water relations in soils.
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Storm Hydrology
There are significant effects of the compost amendment on water relations in these soils. For
instance, Figure R-1a to R-4b show results of four storm simulations for periods starting April 25,
May 11, May 15 and May 25, 1995. These simulated storms ranged in total amounts from 1.4 to
4.8 inches, and in rates from 0.29 to 0.47 inches per hour. Though other events were sampled and
measured, there were problems with the waterflow collectors, and data is not presented here.
The first storm simulation clearly shows the general results, which were consistent throughout
the study periods. For instance, Figure R-1a shows the rainfall, runoff (subsurface + surface
flow), and storage for the period starting 8:30 AM April 25, 1995. The Y axis is given in liters
(per 15 minute period), and the y axis hours from start of event. Following the start of the rainfall
event, there is an increased lag time before significant runoff occurs (Figure R-1a and R-1b). The
compost-amended plot continues to store higher rates and total amounts of water for a longer
period of time. Following cessation of rainfall inputs, there are higher rates of runoff for a longer
period of time. Quicker runoff response to rainfall events is the classic response of hydrology to
urbanization, and this is clearly illustrated in Figure R-1a and R-1b. The total storage is also
increased with the compost amendment, increasing from about 300 to 500 liters, and the field
capacity is also increased from about 250 to 400 liters.
Numerical characteristics of the response hydrology are summarized in Table R-1 for
Simulation 1. Following the start of rainfall onto the sites at the rate of about 0.3 in/hour, it takes
the control unamended plot 1 approximately 30 minutes to respond with runoff > 0.01 in/hour
from an initial flow of nearly zero. The compost-amended site takes 1.0 hour or nearly twice as
long to respond with flow > 0.01 in/hour. It takes 0.75 hours from the start of the rainfall
simulation for flow to become > 0.1 in/hour in the unamended soil, while it takes 1.75 hours for
the compost-amended soil to increase to that rate, an increase of 1 hour compared to the
unamended site. In order for the runoff to reach 90% of input rate, it takes nearly 2.0 hours for the
unamended site compared to 5.25 hours for the compost amended site, an increase of 3.25 hours
compared to the control. This is an intense storm and results for moderate storms would likely
show similar results.
Following the cessation of rainfall, it takes 0.75 hours for runoff in the unamended site to drop
to < 10% of the rate of input, where it takes 1.5 hours for the compost-amended site, an increase
of 0.75 hours. It takes 1.75 hours following the cessation of rainfall for runoff in the unamended
site to drop to <0.01 in/hour, while it takes 6.5 hours for the compost-amended site, an increase of
4.75 hours.
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Similar results are seen with the additional three sampling periods, with storms of lesser total
amounts, including one series of natural rainfall events (Figures R-2a to R-4b). Compostamended soils consistently had longer lag times to response, longer times to peak flows, higher
base flows, higher total storage, and smaller total runoff than unamended soils. This indicates that
compost-amended soils have better water-holding and runoff characteristics than unamended
Alderwood soils and streamflow characteristics would likely benefit from an amendment made to
Alderwood soils in the region.
Water Chemistry
Caveats. We believe it is important to start with a cautionary note in terms of directly
comparing the concentrations of unamended with compost-amended plots in terms of the practical
use of compost vs. inorganic fertilizers in a field situation to achieve a desired turf. If there is a
minimum standard of aesthetic for the turf for a given area of land, whether it is compostamended or not, it is apparent from the visual appeal of the sites at CUH that more inorganic
fertilizer will be applied in the unamended vs. the compost-amended Alderwood soils to achieve
the same visual appeal. Following planting, compost-amended plots developed a dark green color
quickly, and achieved 100% coverage much more rapidly than unamended plots. At the end of
this study, the compost-amended sites were much better aesthetically, with a darker green color
and no bare spots. No soil can be seen through the grass. There are many bare spots with exposed
soil in the plots that did not receive compost amendment. The rates of growth of turf were also
greater even after a considerable period of time. The visual appeal of the compost-amended sites
was much greater during the duration of the study, although all sites did grow grass.
However, when inorganic fertilizer was applied initially, it was applied equally at all sites
since there was nothing but bare ground initially, and in addition, the standard of aesthetic is not
quantitative. Over time, however, it was apparant that it would be very difficult to achieve the
same visual appeal with inorganic fertilizer applied to Alderwood soil only in comparison to the
compost-amended Alderwood soil. Unfortunately, this reduces the utility of this study in
evaluating a compost-amended site that would not receive inorganic P fertilizers. We clearly
needed a comparative study of equal visual appeal. This was not achieved, since the compostamended sites were clearly visually superior.
Overall range of solution concentrations. The average solution analysis concentrations of
samples are given Table R-2, with each individual sample analyzed given in Appendix 2, and
averages of each plot in Appendix 3. It is obvious that there is a great deal of variation in P and N
chemistry in runoff from these results. For instance, the average total P (TP) concentration for all
samples analyzed was 2.29 mg/l while the minimum P was 0.07 and the maximum 21.0 mg/l
Effect of Compost on P Runoff Final Report
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(Appendix 2, Appendix 3 and Table R-2). This represents a high degree of variation (greater than
100x) in concentration. This is not wholly unexpected in a system such as the one studied with
treatments ranging from surface runoff with high water flow in a very infertile, unfertilized glacial
till soil to surface and subsurface runoff in soils freshly fertilized with soluble NPK fertilizers.
Basic conclusions are as follows
1) The high amount of variation (S.D. generally > 100%) seen in these results makes drawing
specific and consistent conclusions with statistical significance difficult.
2) It was also not possible to directly compare compost-amended with unamended plots
statistically (i.e. by ANOVA), since there are only two control plots at the CUH.
The soluble-reactive P (SRP) concentration for all samples analyzed was 1.14 mg/l while the
minimum P was 0.01 and the maximum 7.02 mg/l (Appendix 2, Appendix 3 and Table R-2),
indicating that the SRP was generally a little less than half of the total for all samples (SRP/TP
ration for all samples = 0.42). The average SRP concentration measured is considerably above the
Water Quality recommendations for freshwater according to WAC 173-201 (1992), which is
0.100 for flowing water not discharging directly into a lake or impoundment. There is no standard
for total phosphorus or nitrate. .
The NO3-N concentration averaged 1.54 mg/l while the minimum NO3-N was 0.17 and the
maximum 9.14 mg/l (Appendix 2, Appendix 3 and Table R-2). Thus, the variation of solution
NO3-N was also quite high, ranging nearly 100x in concentration.
Averages-comparison of amended vs. unamended. For overall averages, there was not a
great deal of difference between runoff collected from compost-amended and unamended plots.
For instance, runoff solutions had TP concentration averages of 2.54 mg/l in unamended vs. 2.05
mg/l for the compost-amended plots, indicating that overall, the amended sites had lower total P.
This was true for SRP as well, with runoff averaging 1.19 mg/l in unamended vs. 1.09 mg/l for the
compost-amended plots (Table R-2). The OP was higher in compost-amended soils, averaging
1.29 mg/l in unamended vs. 0.85 mg/l for the compost-amended plots.
Runoff solutions had NO3-N concentration averages of 1.39 mg/l in unamended vs. 1.68 mg/l
for the compost-amended plots, indicating that overall, the amended sites had higher NO3-N
(Table R-2).
Storm events-comparisons. Since the most direct comparisons that can be made are between
plot 1 (unamended Alderwood soil 1) vs. plot 2 (2:1 Cedar Grove fine compost:Alderwood soil
1), and between plot 5 (unamended Alderwood soil 2) vs. plot 6 (2:1 GroCo compost:Alderwood
soil 2), the plots of runoff concentrations vs. time are grouped comparing plot 1 with 2 and plot 5
with 6. Though there is a great deal of variation in the data, as mentioned earlier, there are some
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trends in total P concentrations with time. It is also clear that the fertilization treatment in May
that fertilization has an immediate effect on the P concentration of runoff from these sites.
Figure R-5 and Figure R-6 show TP vs. event number (from Table M-2) for Plot 1 and 2
surface and subsurface runoff. The concentrations for collection intervals 1-7 are relatively low,
but the concentration of the control unamended increases greatly following fertilization with
organic fertilizer, increasing to 14.2 for the surface and 18.0 for subsurface runoff (Figure R-5 and
Figure R-6) collected during the 05/27/95--09:00-12:20 interval. The total P concentrations
decrease gradually over the following 2 weeks of collection and return to about their original
baselines. The compost-amended plots, which neither needed nor received fertilizer, also had
increases in TP concentrations, probably associated with increase organic matter decompostition
and release of mineral nutrients.
By the end of the study, the total P concentrations of solutions collected from surface and
subsurface runoff from plot 1 and 2 were nearly the same (Figure R-6). High concentrations
appeared to be associated with the fertilization treatment of unamended plot 1, and the P in these
samples was highly soluble. For instance, 60% of the total P in the surface runoff from the
05/27/95--09:00-12:20 collection interval from plot 1 was SRP and nearly 40% of the P in the
subsurface runoff was SRP.
The TP concentrations in plot 5 (unamended Alderwood soil 2) and plot 6 (2:1 GroCo
compost:Alderwood soil 2) show results very similar to those for plot 1 and 2. For instance,
Figure R-7 shows TP vs. event number (from Table M-2) for Plot 5 and 6 surface and subsurface
runoff. The concentrations are lower then 5 mg/l until after the second fertilization of control
plots, and then it increases rapidly (maximum >20mg/l) for the control plot 5 for several sampling
periods after that. The concentrations drop rapidly and by sampling period 32, the concentrations
of total P are below 5 mg/l again.
Soluble-reactive P (SRP) is the most bioavailable fraction of P analyzed in this study. SRP
concentrations are lower than total P concentrations for all samples taken at the same time, and
also generally lower overall. When plots 1 and 5 are fertilized, the SRP also increases greatly in
the unamended plot, and generally decreases back to previous levels after several weeks (Figure
R-8). The same general pattern of response to fertilization is seen in plot 5 (unamended
Alderwood soil 2), compared to plot 6 (2:1 GroCo compost:Alderwood soil 2). Following the
second fertilization of unamended plots on May 2, SRP concentrations increase abruptly for plot
5, and then decrease after several weeks of elevated SRP concentrations. Overall, concentrations
of SRP are lower for the compost-amended vs. control plots (Figure R-8 and R-9).
Nitrate concentrations varied considerably in these studies and there was no clear pattern.
There was no apparent increase in Nitrate concentration following the second fertilization of the
Effect of Compost on P Runoff Final Report
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control plots on May 25, either, which is unexpected. Apparently, the control plots are nitrogen
and not phosphorus-limited in fertility, such that an increase in the availability of nitrogen does
not necessarily increase the solubility since the plants and microbes in the soil retain that added
nitrogen, and do not allow it to mineralize to nitrate. This variability in nitrate concentration can
be seen in Figure R-10 and Figure R-11.
Hydrology and Water Chemistry Assimilation
The hydrology data and phosphorus and nitrogen data was combined to estimate loss of SRP,
total P and nitrate from plots for periods of time where the hydrology and chemistry data were
considered to be adequate to calculate flux (i.e. no problems with tipping buckets, and no
problems with overflow of nutrient-solution collectors). Early problems with hydrology preclude
the use of some data for hydrology (as indicated in Table M-1), and all storms were not adequately
sampled for chemistry. Collection periods for which adequate data are available includes the
collection periods from May 15-16, May 25-26, May 30-June 3, and June 6-10.
Data were merged by applying the concentration of the solution (in mg/liter) collected by the
runoff volume (in liters) for surface and subsurface collectors for each 15-minute increment of
time. The amount of nutrient that is lost from the plot in this runoff was then summed and plotted
over time. Since there were problems with estimating surface vs. subsurface runoff in volumes,
and solution collection was volume-weighted, no separation of nutrient loss from surface vs.
subsurface runoff was attempted. The estimated nutrient production is thus mg per plot, and these
units are used in Figure R-12 to R-15.
May 15-16 Sampling Period. The data from the May 15-16 sampling period shows that
following establishment of plots 5 and 6 to turfgrass during the winter and spring of 1994-1995,
the nutrient output is quite low (Figure R-12). For instance, for a 30 hour period starting 8:00 AM
on May 15, 1995, only 25 mg of SRP, 493 mg of total P, and 959 mg of nitrate were lost as runoff
from plot 5 (unamended Alderwood soil 2), and 320 mg of SRP, 684 mg of total P, and 780 mg of
nitrate were lost as runoff from plot 6 (2:1 GroCo compost:Alderwood soil 2), despite the 1.8 in
of rainfall applied to the sites, and the large production of runoff (Figure R3a and R-3b). In these
events, the SRP is almost 10 times as high for the compost-amended vs. unamended, but the total
P is comparable. This may indicate that much of the P from the control site is particulate (it was
noted that control sites had higher suspended matter), while from the compost site it is soluble.
These total amounts of P are relatively small compared to runoff from the events following
fertilization of the plots.
Effect of Compost on P Runoff Final Report
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May 25-26 Sampling Period. The effect of the May 25 fertilization is readily apparent in the
measured runoff for the May 25-26 event (Figure R-13). Note that the runoff production scale for
these events is nearly 20 times that of the May 15-16 sampling event. A total of 5,200 mg vs.
1,900 mg of SRP was produced from the unamended plot 5 compared to the compost-amended
plot 6 (Figure R-13). A total of 12,600 mg vs. 3,200 mg of total P was produced from the
unamended plot 5 compared to the compost-amended plot 6 (Figure R-13). A total of 17,500 mg
of total P was added with the amendment of May 15, so this represents over 72% of the original
fertilizer amendment running off with the first storm on plot 5. Thus, it appears that the
unamended plot has very little ability to retain fertilizer P during an intense storm event. Less
obvious is the reason why the unamended plot 6 also increased P production. This increase was
much less than that seen in plot 5. Bruce Jensen offered some insight into a possible reason when
he noted that semi-wild Canada geese living in the area seem to love eating grass on the compostamended plots, while ignoring the unamended plots. During these feedings they also leave a
considerable amount of droppings, which probably have high amounts of soluble inorganic
nutrients associated with them. Unfortunately, these factors make the comparisons of these sites
suspect. An additional explanation that may be likely is the increased mineralization of organic
matter as the weather warms and organic matter decomposition rates (that release mineral P)
increase.
The runoff of nitrate was almost identical for site 5 vs. site 6 (Figure R-13), with 2,052 mg for
site 5 vs. 2,219 mg for site 6 produced during the storm events. Nearly 160,000 mg of N was
added with the fertilization amendment, but there does not appear to be a significant effect of this
amendment on nitrate. Thought the fertilizer was not analyzed and no comparison of ammonium
vs. nitrate was given, it is likely that most of the nitrogen was in an ammonium form. This could
have been produced in the runoff in high concentrations. Since there was no NH4 analysis done
on the samples, it is unknown if this actually did occur.
May 30-June 3 Sampling Period. Samples were collected over longer periods of time
starting at the end of May (Figure R-14). Sampling was conducted during a 120 hour period
starting 8:00 AM on May 31, 1995 on 1 (unamended Alderwood soil 1) plot 2 (2:1 Cedar Grove
fine compost:Alderwood soil 1). A total of 392 mg of SRP, 1405 mg of total P, and 1209 mg of
nitrate were lost as runoff from plot 1, while 466 mg of SRP, 849 mg of total P, and 1184 mg of
nitrate were lost as runoff from plot 2. Note that an increasing amount of the P in the unamended
plot is insoluble, and probably of the particulate form.
The data from this sampling period shows the nutrient P concentrations and total runoff
following the fertilization event are dropping quickly in the control plot. Remember that 72% of
the total P was lost during the first 30 hours following fertilization during the May 25-26
Effect of Compost on P Runoff Final Report
page 16
simulated storms, so there may not be much of the original P left in these sites. In the case of plot
6, the geese were still visiting the site during this time, and this may affect the results due to their
droppings, which contain high amounts of P.
June 3-10 Sampling Period. A long-term collection of runoff was conducted from June 3-10
(Figure R-15). Sampling was conducted during a 180 hour period starting 10:00 AM on June 3,
1995 on plot 1 (unamended Alderwood soil 1), and plot 2 (2:1 Cedar Grove fine
compost:Alderwood soil 1). A total of 40 mg of SRP, 94 mg of total P, and 468 mg of nitrate
were lost as runoff from plot 1, while 42 mg of SRP, 61 mg of total P, and 386 mg of nitrate were
lost as runoff from plot 2. Most of the production of P and N from the compost-amended plot was
during periods well after the artificial storm events, whereas most of the nutrient production from
the unamended plot was during or immediately following the storm event.
These data show that nutrient production has dropped considerably compared to the storms of
May. For the control plot which received an additional fertilizer amendment after establishment,
this would point at the loss of soluble P due to loss and adsorption following the fertilizer
addition. It is uncertain why the production is lowering in the compost-amended plots, but it may
be due to an increasing demand for available nutrients by the rapidly growing grass in a system
that is now more depleted of available nutrients. Unfortunately, the high amount of varibility and
lack of suitable replication of plots in this study make conclusions difficult.
It should be noted that the artificial storms utilized in these studies represent intense rainfall
events of 25-100 year return intervals. It would be expected that the differences between the tillonly soil and the compost-amended till soil would be greater at less-intense rainfall events, though
the peak rates of runoff of both are likely to be reduced.
SUMMARY AND CONCLUSIONS
Summary of Results
Nutrient production from sites was highly variable, but following intense leaching during the
winter of 1994 and spring of 1995, concentrations and total runoff of P was slightly higher from
compost-amended sites. Nitrate concentrations and runoff were about the same. However, there
was insufficient grass growth in unamended sites, even following an establishment fertilization, so
an additional fertilizer addition was made. The compost-fertilized site was very attractive and
needed no fertilization. In fact, the initial establishment fertilization probably wasn’t necessary
either based on studies of turfgrass growth in compost-amended soils without inorganic
fertilization at the University of Washington on similar soils. Following the fertilizer addition in
Effect of Compost on P Runoff Final Report
page 17
the control plots, 72% of the P fertilizer added immediately ran off the site during the first storm
following fertilization, resulting in a 200-fold increase in P runoff with a single storm. The
fertilizer did seem to increase the rate of grass growth, and nutrient concentrations rapidly
decreased over time in the control sites. The limited results available from these studies point out
the necessity of conducting a field study that incorporates sufficient repetitions, time, and
fertilization regimes that establish similar turfgrass. Unfortunately, a lot of effort was spent on
development of methods of conducting this study, since none like has been conducted previously.
The results of these studies clearly show that compost amendment alters soil properties known
to affect water relations of soils, including the water holding capacity, porosity, bulk density, and
structure, as well as increasing soil C and N, and probably other nutrients as well. Results also
show that compost amendments affect water runoff patterns during and following storm events,
and runoff of nutrients from unamended vs. amended sites. In all cases, compost amendment
increased the lag time of response of a soil runoff hydrograph to a storm event, increased the time
to peak flow, decreased the rapidity of drop of the hydrograph following cessation of the storm
event, and increased the "base flow" in the period following the storm event. The amendment
increased the peak storage and field capacity of plots nearly 100%, and reduced the total runoff
depending on the intensity and duration of the storm event (i.e. small storms = little or no runoff;
large storms = almost complete runoff). Following one storm with another showed that
antecedent conditions were very important in determining total runoff from a particular storm
event.
These observations were true of both the Cedar Grove and GroCo amendments. However, the
GroCo:soil 2 combination appeared to have a much higher water holding capacity than the Cedar
Grove:soil 1 mixture. This is probably due to the fact that the GroCo is made with biosolids, and
contains much more finely divided and decomposed organic matter as well as flocculants
designed to precipitate suspended material from water during the water treatment process. GroCo
amendment also had a more pronounced effect on increasing lag times and base flows.
Implications of Results
Nutrient runoff was affected by compost amendment, but primarily from the lowering of total
runoff amounts and not due to lowering of nutrient concentrations in runoff. Compost-amended
turfgrass was uniformly beautiful, and required little or no fertilization, which is a definite
positive aspect of compost amendment. The poor quality of the unamended plots would likely
have resulted in addition nutrient application, and when we did this, almost all of the P fertilizer
ran off with the next storm event. This resulted in much more nutrient runoff from sites not
Effect of Compost on P Runoff Final Report
page 18
amended with compost compared to compost-amended sites. This may actually be the biggest
benefit of compost amendment...lack of need for further lawn fertilization.
Application of compost material similar to that in this study would be possible by applying 4
inches of compost onto the surface of an Alderwood soil and tilling to a total depth of 12 inches,
including the compost amendment (8 inches into the soil). This mixing would probably need to
be thorough and deep to achieve the conditions of this study, and this is not likely to be possible
with most existing equipment. However, if the compost is well incorporated into the soil, most of
the benefits of amendment seen in this study would likely be seen from a field application.
The results of this study clearly show that compost amendment is likely an effective means of
decreasing peak flows from all but the most severe storm events following very wet antecedent
conditions. An added benefit of amendments is an increased base flow in antecedent conditions
following storm events. The increases in water holding capacity with compost amendment shows
that storms up to 0.8 inches total rainfall would be well buffered in amended soils and not result in
significant peak flows, whereas without the amendment a storm about 0.4 inches total rainfall
would be similarly buffered.
If a significant percentage of till soils disturbed were amended with compost in this manner, it
would have this positive effect on hydrology. The absolute amount depends on many factors, but
it is clear that compost amendment is an excellent means of retaining runoff on-site and reducing
the rate of runoff from all but the most intense storm events. The effect of compost amendment
on total runoff amounts during the wettest parts of the winter would likely be minimal on these
Alderwood soils since there is very little transpiration during the winter. However, during the
early fall and late spring seasons, the additional water-holding capacity of the compost-amended
soils would result in additional transpiration from the plots and possibly lowered need for
irrigation. Despite the lack of probable effect on total runoff during the winter season, the effect
on storm peak flows would clearly be beneficial.
Future Directions
The resources of this study were largely consumed figuring out how to get these sampling
systems to work. Although there will always be similar problems in such studies, a lot more
stands to be gained from additional work on the CUH sites. For instance, a range of mediumintensity simulated storms needs to be run, and longer-term evaluations could be made since all
plots are likely to change in chemistry and structure over time. Two critical questions need to be
answered:
1) Is the compost amendment permanent?
Effect of Compost on P Runoff Final Report
page 19
2) Will the properties of the unamended site improve with time?
If these question could be answered utilizing these sites, the long-term effect of the amendment
could be evaluated.
In addition, a series of field trials would ideally be created, with the area of compost-amended
vs. unamended evaluated from runoff into a small catchment. Whether or not such a site exists is
not easily answered here, but such a test of the utilization of compost would be the ideal means to
test its effect on runoff quantity and quality. Ideally, any future study would include a turf
established with other common commercially-utilized methods, such as the practice of placing
sod directly onto glacial till soil.
Effect of Compost on P Runoff Final Report
page 20
Table M-1. Storm S imulation Summary characteris tics†
Start
date
Plots
studied
Start
time
1&2
1&2
930
930
duration
–– h ––
8
8
1&2
1&2
900
1430
1.5
2
0.95
0.89
0.63
0.45
Plot 1 bucket overflowed
May 13
1&2
900
3
1.42
0.47
Natural storm on previous day
May 16
May 17
5&6
5&6
930
1000
3
2
1.04
0.76
0.35
0.38
Gutters covered
Gutters covered
May 25
May 26
5&6
5&6
1200
1200
6
6
2.06
2.03
0.34
0.34
Gutters covered
Gutters covered
§ May 28
1&2
900
6
1.90
0.32
Buckets stuck on both plots!!!
Gutters covered
§ May 30
§ May 31
1&2
1&2
1000
1000
6
6
1.85
1.87
0.31
0.31
Plot 1 bucket stuck???
Gutters covered
June 9
1&2
1000
3
April 26
April 27
§ May 5
§ May 6
Average
depth
Rate Comments¥
–– in –– –– in/h ––
2.46
0.31
2.33
0.29
Gutters covered
† data from Kyle Kolsti, UW Center for Urban Water Res ources
¥ hydrology data highlighted in italics had one or more problems and was deleted from
consideration in the hydrology results section
§ storm data not analyzed due to problems noted in "Comments"
Effect of Compost on P Runoff Final Report
page 21
Table M-2. Summary of Run Collection Times
Field
Run
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
Collector placed
On
03/07/95--10:30
04/25/95--09:00
04/27/95--10:00
05/01/95--10:18
05/04/95--09:30
05/08/95--09:30
05/12/95--09:00
05/15/95--09:00
05/15/95--12:45
05/15/95--13:15
05/16/95--10:14
05/16/95--12:15
05/16/95--12:30
05/16/95--13:00
05/24/95--12:05
05/25/95--11:45
05/25/95--15:30
05/25/95--18:06
05/25/95--18:21
05/26/95--21:15
05/26/95--21:30
05/27/95--09:00
05/27/95--12:20
05/27/95--15:15
05/27/95--15:46
05/27/95--21:10
05/31/95--10:00
05/31/95--16:30
05/27/95--21:10
05/31/95--10:00
05/31/95--16:30
06/03/95--10:10
06/06/95--19:52
06/09/95--10:00
06/09/95--20:10
06/09/95--10:00
Collector taken
Off
03/15/95--09:00
04/26/95--09:00
04/28/95--11:00
05/03/95--18:00
05/08/95--09:30
05/12/95--09:00
05/15/95--09:00
05/15/95--12:45
05/15/95--13:15
05/16/95--10:10
05/16/95--12:15
05/16/95--12:30
05/16/95--13:00
05/24/95--12:00
05/25/95--11:30
05/25/95--15:20
05/25/95--18:06
05/25/95--18:21
05/26/95--21:15
05/26/95--21:30
06/03/95--10:10
05/27/95--12:20
05/27/95--15:15
05/27/95--15:46
05/27/95--21:10
05/31/95--09:55
05/31/95--16:30
06/03/95--10:10
05/31/95--09:55
05/31/95--16:30
06/03/95--10:10
06/06/95--19:52
06/09/95--10:00
06/09/95--20:10
06/10/95--20:16
06/10/95--20:16
Sampling duration
(hours)
191
24.0
25.0
56
96
95
72
3.8
0.5
20.9
2.0
0.3
0.5
191
23.4
3.6
2.6
0.2
26.9
0.3
181
3.3
2.9
0.5
5.4
85
6.5
66
85
6.5
66
82
62
10.2
24.1
34.3
Effect of Compost on P Runoff Final Report
Table R-1. Hydrological characteristics of s imulated rainfall
hydrologic
characteristic
total input
rainfall rate
runoff > 0.01 in/hour
runoff > 0.1 in/hour
runoff rate > 90% input rate
runoff < 10% of input rate†
runoff < 0.01 in/hour
total input
rainfall rate
runoff > 0.01 in/hour
runoff > 0.1 in/hour
runoff rate > 90% input rate
runoff < 10% of input rate†
runoff < 0.01 in/hour
additional
control
compost
lag with
unamended
amended
compost
––––––––– simulation 1, storm 1 –––––––––
2.33 in
2.46 in
0.28 in/h
0.30 in/h
0.50 h
1.00 h
0.50 h
0.75 h
1.75 h
1.00 h
2.00 h
5.25 h
3.25 h
0.75 h
1.50 h
0.75 h
1.75 h
6.50 h
4.75 h
––––––––– simulation 1, storm 2 –––––––––
2.09 in
2.29 in
0.26 in/h
0.29 in/h
0.25 h
0.50 h
0.25 h
0.50 h
1.00 h
0.50 h
0.75 h
1.25 h
0.50 h
0.75 h
1.50 h
0.75 h
1.75 h
>2.00 h
page 22
Effect of Compost on P Runoff Final Report
page 23
Table R-2. Summary statis tics for solution chemis try analyses
Treatment
average (treated and control)
analyzed in laboratory
total
Acid
reactive digested
Total
NitrateP
P
P
nitrogen
SRP
ACP
TP
NO3-N
derived measures
Occluded
Organic
P
P
(ACP-TP) (TP-ACP)
OCP
OP
–––––––––––––––– average concentration (mg/l) –––––––––––––––––––
1.14
1.51
2.29
1.54
0.24
1.06
control unamended
compost amended
1.19
1.09
1.56
1.46
2.54
2.05
1.39
1.68
0.25
0.22
1.29
0.85
control unamended lower
compost amended lower
1.04
1.22
1.22
1.59
2.07
2.43
1.57
1.75
0.13
0.24
0.99
1.11
control unamended upper
compost amended upper
1.40
0.91
2.06
1.25
3.17
1.53
1.16
1.57
0.43
0.19
1.71
0.45
Effect of Compost on P Runoff Final Report
page 24
Figure M-1. University of Washington Center for Urban Water
Resources compost amendment research site layout.
32'
8'
control
soil 1
2:1 CG fine
soil 1
weather
station
2:1 CG coarse soil 1
4:1 CG fine
soil 1
control
soil 2
2:1 GroCo
soil 2
3:1 CG fine
soil 2
Detail of Soil Sampling Scheme
3
1
2
4
4' 5
6
7
8
1'
2'
2'
8'
5'
16'
9'
Effect of Compost on P Runoff Final Report
page 25
Interval flows (liters/hour)
160
120
Plot 1
Control unamended
80
40
0
0
5
10
-40
15
20
Hours from start of event
25
30
35
25
30
35
Interval flows (liters/hour)
200
160
120
Plot 2
Compost amended
80
40
0
-40
0
5
10
15
20
Hours from start of event
start 8:30 AM
April 25, 1995
Figure R-1a. Comparison of intervals of
rainfall, runoff, s urface flow, s ubsurface
flow and s torage volumes for plot 1
(control) and 2 (amended) for sequential
rainfall events s tarting April 25, 1995.
Rainfall
Runoff
Surface flow
Subsurface flow
Storage
Effect of Compost on P Runoff Final Report
page 26
Water balance for storm event
Rainfall
unamended amended
–––––– liters ––––––
total liters per plot
2,780
2,997
percent runoff
percent retention
inches storm event
4.60
4.96
inches runoff
inches retention
Runoff
unamended amended
–––––– liters ––––––
2,491
2,658
90
89
10
11
4.12
0.48
4.40
0.56
3000
total rainfall
control unamended
compost-amended
2500
Total flux (liters)
2000
1500
1000
total runoff
control unamended
compost-amended
500
0
Hours from start of event
Total storage (liters)
600
500
compost-amended
400
300
control unamended
200
rainfall storage
control unamended
compost-amended
100
0
0
start 8:30 AM
April 25, 1995
5
10
15
20
Hours from start of event
25
30
Figure R-1b. Comparison of total rainfall input, cumulative runoff, and net storage
for plot 1 (control) and 2 (amended) for sequential rainfall events starting April 25,
1995.
35
Effect of Compost on P Runoff Final Report
page 27
160
140
Interval flows (liters/hour)
120
100
80
Plot 1
Control unamended
60
40
20
0
0
5
10
Hours from start of event
15
20
25
15
20
25
Interval flows (liters/hour)
120
100
80
60
Plot 2
Compost amended
40
20
0
-20 0
5
-40
10
Hours from start of event
-60
start 2:00 PM
May 11, 1995
Figure R-2a. Comparison of intervals of
rainfall, runoff, s urface flow, s ubsurface
flow and s torage volumes for plot 1
(control) and 2 (amended) for rainfall
event starting May 11, 1995.
Rainfall
Runoff
Surface flow
Subsurface flow
Storage
Effect of Compost on P Runoff Final Report
page 28
Water balance for storm event
Rainfall
unamended amended
–––––– liters ––––––
total liters per plot
1,081
1,081
percent runoff
percent retention
inches storm event
1.79
1.79
inches runoff
inches retention
Runoff
unamended amended
–––––– liters ––––––
740
639
68
59
32
41
1.22
0.56
1.06
0.73
1200
total rainfall
control unamended and compost-amended
Total flux (liters)
1000
800
600
total runoff
control unamended
compost-amended
400
200
0
0
5
10
15
Hours from start of event
20
25
Total storage (liters)
600
500
400
300
rainfall storage
control unamended
compost-amended
200
100
0
0
5
10
15
20
start 2:00 PM
Hours from start of event
May 11, 1995
Figure R-2b. Comparison of total rainfall input, cumulative runoff, and net storage
for plot 1 (control) and 2 (amended) for sequential rainfall events starting May 11,
1995.
25
Effect of Compost on P Runoff Final Report
page 29
Interval flows (liters/hour)
50.0
40.0
30.0
20.0
Plot 5
Control unamended
10.0
0.0
0
5
10
15
20
25
30
20
25
30
Hours from start of event
Interval flows (liters/hour)
50.0
40.0
30.0
20.0
Plot 6
Compost amended
10.0
0.0
0
5
start 8:00 AM
May 15, 1995
10
15
Hours from start of event
Figure R-3a. Comparison of intervals of
rainfall, runoff, s urface flow, s ubsurface
flow and s torage volumes for plot 5
(control) and 6 (amended) for rainfall
event starting May 15, 1995.
Rainfall
Runoff
Surface flow
Subsurface flow
Storage
Effect of Compost on P Runoff Final Report
page 30
Water balance for storm event
Rainfall
unamended amended
–––––– liters ––––––
total liters per plot
1,041
1,081
percent runoff
percent retention
inches storm event
1.72
1.79
inches runoff
inches retention
Runoff
unamended amended
–––––– liters ––––––
798
347
77
32
23
68
1.32
0.40
0.57
1.22
1200
total rainfall
control unamended and
compost-amended
1000
Total flux (liters)
800
total runoff
control unamended
compost-amended
600
400
200
0
0
5
10
15
Hours from start of event
20
25
30
800
Total storage (liters)
700
600
500
rainfall storage
control unamended
compost-amended
400
300
200
100
0
0
5
10
15
20
25
start 8:00 AM
Hours from start of event
May 15, 1995
Figure R-3b. Comparison of total rainfall input, cumulative runoff, and net storage
for plot 5 (control) and 6 (amended) for sequential rainfall events starting May 15,
1995.
30
Effect of Compost on P Runoff Final Report
page 31
Interval flows (liters/hour)
50.0
40.0
30.0
Plot 5
Control unamended
20.0
10.0
0.0
0
5
10
Interval flows (liters/hour)
-10.0
15
20
Hours from start of event
25
30
35
40
25
30
35
40
50.0
40.0
30.0
Plot 6
Compost amended
20.0
10.0
0.0
-10.0
0
5
start 11:00 AM
May 25, 1995
10
15
20
Hours from start of event
Figure R-4a. Comparison of intervals of
rainfall, runoff, surface flow, subs urface
flow and storage volumes for plot 5
(control) and 6 (amended) for rainfall
event starting May 25, 1995.
Rainfall
Runoff
Surface flow
Subsurface flow
Storage
Effect of Compost on P Runoff Final Report
page 32
Water balance for storm event
Rainfall
unamended amended
–––––– liters ––––––
total liters per plot
2,432
2,432
percent runoff
percent retention
inches storm event
4.03
4.03
inches runoff
inches retention
Runoff
unamended amended
–––––– liters ––––––
1,749
1,214
72
50
28
50
2.90
1.13
2.01
2.02
2500
total rainfall
control unamended and
compost-amended
Total flux (liters)
2000
1500
1000
total runoff
control unamended
compost-amended
500
0
0
5
10
15
20
Hours from start of event
25
30
35
40
0
5
10
15
20
25
30
35
start 11:00 AM
Hours from start of event
May 25, 1995
Figure R-4b. Comparison of total rainfall input, cumulative runoff, and net storage
for plot 5 (control) and 6 (amended) for sequential rainfall events starting May 25,
1995.
40
Total storage (liters)
1400
1200
1000
rainfall s torage
control unamended
compost-amended
800
600
400
200
0
Effect of Compost on P Runoff Final Report
page
33
20
Total P concentration (mg/L)
15
10
Treatments
5
Plot 1
control unamended
surface
subsurface
Plot 2
compost amended
surface
subsurface
0
0
2
4
6
8
10
12
14
16
18
20
22
24
26
28
Event number (see Table R-1 for s ampling durations).
Figure R-5. Total P concentration of plot 1 (control unamended) and plot 2 (compost-amended).
30
32
34
36
Effect of Compost on P Runoff Final Report
page
34
20
Total P concentration (mg/L)
15
Treatments
10
Plot 1
control unamended
surface
subsurface
Plot 2
compost amended
surface
subsurface
5
0
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
Event number (s ee Table R-1 for sampling durations).
Figure R-6. Total P concentration following fertilization of plot 1 (control unamended) and plot 2 (compost-amended).
36
Effect of Compost on P Runoff Final Report
page
35
25
plots 1 & 5
fertilized
Total P concentration (mg/L)
20
15
Treatments
Plot 5
control unamended
surface
subsurface
Plot 6
compost amended
surface
subsurface
10
5
0
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36
Event number (see Table R-1 for s ampling durations).
Figure R-7. Total P concentration of plot 5 (control unamended) and plot 6 (compost-amended).
Effect of Compost on P Runoff Final Report
page
8
6
Soluble Reactive Phosphate (mg/L)
Treatments
4
Plot 1
control unamended
surface
Plot 2
compost amended
surface
subsurface
subsurface
2
plots 1 & 5
fertilized
0
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36
Event number (s ee Table R-1 for sampling durations).
Figure R-8. Soluble reactive phosphate concentration of plot 1 (control unamended) and plot 2 (compost-amended).
36
Effect of Compost on P Runoff Final Report
page
37
8
Soluble Reactive Phosphate (mg/L)
plots 1 & 5
fertilized
Treatments
Plot 5
control unamended
surface
Plot 6
compost amended
surface
6
subsurface
subsurface
4
2
0
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36
Event number (see Table R-1 for s ampling durations).
Figure R-9. Soluble reactive phos phate concentration of plot 5 (control unamended) and plot 6 (compost-amended).
Effect of Compost on P Runoff Final Report
page
10
Total NO3-N concentration (mg/L)
9
8
7
Treatments
6
Plot 1
control unamended
surface
subsurface
5
Plot 2
compost amended
surface
subsurface
4
3
2
plots 1 & 5
fertilized
1
0
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36
Event number (see Table R-1 for s ampling durations).
Figure R-10. Total NO3-N concentration following fertilization of plot 1 (control unamended) and plot 2 (compos t-amended).
38
Effect of Compost on P Runoff Final Report
6
Total NO3-N concentration (mg/L)
5
4
page
39
plots 1 & 5
fertilized
Treatments
Plot 5
control unamended
surface
Plot 6
compost amended
surface
subsurface
subsurface
3
2
1
0
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36
Event number (s ee Table R-1 for sampling durations).
Figure R-11. Total NO3-N concentration following fertilization of plot 5 (control unamended) and plot 6 (compost-amended).
Soluble Phosphate flux
(mg per plot)
Effect of Compost on P Runoff Final Report
350
300
250
200
150
100
50
0
Total Phosphorus flux
(mg per plot)
0
start 8:00 AM
May 15, 1995
Nitrate-N flux
(mg per plot)
320
till soil only
till with compost amendment
25
5
10
20
25
30
684
till soil only
till with compost amendment
493
5
10
15
20
25
30
Time from start of first storm event (hours)
959
1000
900
800
700
600
500
400
300
200
100
0
0
start 8:00 AM
May 15, 1995
15
Time from start of first storm event (hours)
700
600
500
400
300
200
100
0
0
start 8:00 AM
May 15, 1995
page 40
till soil only
till with compost amendment
780
5
10
15
20
25
30
Time from start of first storm event (hours)
Figure R-12. Measured runoff of total P, SRP and NO3-N from May 1516 storm s imulation for plots 5 and 6
Effect of Compost on P Runoff Final Report
page 41
Soluble Phosphate flux
(mg per plot)
6000
5,189
5000
till soil only
till with compost amendment
4000
3000
2000
1,880
1000
0
0
5
Total Phosphorus flux
(mg per plot)
start 11:00 AM
May 25, 1995
10
15
20
25
30
35
40
Time from start of first storm event (hours)
14000
12000
12,657
till soil only
till with compost amendment
10000
8000
6000
4000
2000
3,257
0
0
start 11:00 AM
May 25, 1995
5
10
15
20
25
30
Nitrate-N flux
(mg per plot)
40
Time from start of first storm event (hours)
2500
2000
35
2,219
till soil only
till with compost amendment
2,052
1500
1000
500
0
0
5
start 11:00 AM
May 25, 1995
10
15
20
25
30
35
Time from start of first storm event (hours)
Figure R-13. Measured runoff of total P, SRP and NO3-N from May 2526 storm simulation for plots 5 and 6
40
Soluble Phosphate flux
(mg per plot)
Effect of Compost on P Runoff Final Report
466
500
450
400
350
300
250
200
150
100
50
0
392
till soil only
till with compost amendment
Total Phosphorus flux
(mg per plot)
0
20
40
60
1600
1400
1200
1000
800
600
400
200
0
80
100
120
1405
849
till soil only
till with compost amendment
0
start 8:00 AM
May 31, 1995
Nitrate-N flux
(mg per plot)
page 42
20
40
60
80
100
Time from start of first storm event (hours)
1400
1200
1000
800
600
400
200
0
120
1209
1184
till soil only
till with compost amendment
0
start 8:00 AM
May 31, 1995
20
40
60
80
100
120
Time from start of first storm event (hours)
Figure R-14. Measured runoff of total P, SRP and NO3-N from May 30June 3 storm simulation for plots 1 and 2.
Soluble Phosphate flux
(mg per plot)
Effect of Compost on P Runoff Final Report
42
45
40
35
30
25
20
15
10
5
0
0
20
start 10:00 AM
June 3, 1995
40
Total Phosphorus flux
(mg per plot)
Nitrate-N flux
(mg per plot)
60
80
100
120
140
160
180
Time from start of first storm event (hours)
94
till soil only
till with compost amendment
61
40
60
80
100
120
140
160
180
Time from start of first storm event (hours)
500
450
400
350
300
250
200
150
100
50
0
0
20
start 10:00 AM
June 3, 1995
40
till soil only
till with compost amendment
100
90
80
70
60
50
40
30
20
10
0
0
20
start 10:00 AM
June 3, 1995
page 43
468
till soil only
till with compost amendment
40
60
80
100
386
120
140
160
Time from start of first storm event (hours)
Figure R-15. Measured runoff of total P, S RP and NO3-N from June 6-10
storm simulation for plots 1 and 2
180
Effect of Compost on P Runoff Final Report
page
44
Appendix 1a. Summary of soil analysis data for field plots. Sampled August, 1994.
(note that samples for the August analysis were taken according to Figure M-1 sampling scheme).
Sampled in August, 1994
Plot and rep
Plot 1, rep 1
Plot 1, rep 2
Plot 1, rep 3
Plot 1, rep 4
Plot 1, rep 5
Plot 1, rep 6
Plot 1, rep 7
Plot 1, rep 8
Plot 2, rep 1
Plot 2, rep 2
Plot 2, rep 3
Plot 2, rep 4
Plot 2, rep 5
Plot 2, rep 6
Plot 2, rep 7
Plot 2, rep 8
amended average
no compost average
total total
C
N
% by weight
0.2
0.12
0.3
0.14
0.3
0.13
0.3
0.15
0.2
0.12
0.3
0.10
0.5
0.12
0.2
0.11
2.2
0.26
2.6
0.27
3.4
0.28
2.7
0.25
2.8
0.24
2.0
0.22
2.5
0.30
4.5
0.36
2.8
0.27
0.3
0.12
Field
Field
Capacity Capacity Total
g/g
ml/ml Porosity
%
%
%
20
28
48
18
22
52
18
21
56
18
24
42
16
20
49
16
22
46
16
20
52
28
35
50
37
41
47
39
39
56
34
33
52
32
36
49
33
37
47
32
35
53
46
49
48
27
30
44
35
37
50
19
24
49
Particle Size Analysis
Bulk
Density
g/cm3
1.37
1.22
1.15
1.38
1.28
1.35
1.23
1.26
1.12
0.98
0.95
1.14
1.14
1.07
1.06
1.14
1.08
1.28
Particle
Density
g/cm3
2.63
2.54
2.64
2.39
2.53
2.50
2.54
2.54
2.12
2.23
1.97
2.25
2.13
2.29
2.03
2.05
2.13
2.54
< 2mm parts percentage
2-0.02 0.02-0.005 0.005-0.002 <.002
%
%
%
%
76.3
12.5
1.3
10.0
76.3
11.3
3.8
8.8
76.3
12.5
1.3
10.0
75.0
13.8
3.8
7.5
76.3
13.8
2.5
7.5
76.3
13.8
1.3
8.8
76.3
13.8
1.3
8.8
76.3
12.5
1.3
10.0
73.8
12.5
6.3
7.5
77.5
10.0
5.0
7.5
77.5
10.0
5.0
7.5
77.5
10.0
5.0
7.5
77.5
10.0
5.0
7.5
73.8
12.5
6.3
7.5
76.3
10.0
6.3
7.5
73.8
12.5
6.3
7.5
75.9
10.9
5.6
7.5
76.1
13.0
2.0
8.9
soil structure by
visual and feel
method
single grain / weak granular
single grain / weak granular
single grain / weak granular
single grain / weak granular
single grain / weak granular
single grain / weak granular
single grain / weak granular
single grain / weak granular
single grain / weak granular
single grain / weak granular
single grain / weak granular
single grain / weak granular
single grain / weak granular
single grain / weak granular
single grain / weak granular
single grain / weak granular
Effect of Compost on P Runoff Final Report
page
45
Appendix 1b. Summary of soil analysis data for field plots. Sampled December, 1994.
Caution: sampling of these sites was done under less than ideal conditions when the soils was highly saturated.
This could easily lead to compaction of these sandy-textured soils when sampling for bulk density and affect any porosity-related analysis
Sampled December 13, 1994
Sample designation
plot 1 BD, control
plot 2 BD, CGfine2:1
plot 3 BD, CGcoarse2:1
plot 3 Grab, CGcoarse2:1
plot 4 Grab, CGfine4:1
plot 5 Grab, control
plot 6 Grab, Groco2:1
plot 7 Grab, CGfine3:1
amended average
no compost average
total
C
%
0.2
3.1
3.0
3.1
1.8
0.1
1.2
2.2
2.4
0.2
total
N
%
0.02
0.20
0.23
0.23
0.13
0.05
0.06
0.16
0.17
0.04
Field
Field
Capacity Capacity Total
g/g
ml/ml Porosity
%
%
%
19
41
38
46
24
29
35
34
35
39
29
19
Particle Size Analysis
Bulk
Density
g/cm3
1.97
1.16
1.45
1.30
1.97
Particle
Density
g/cm3
2.33
1.99
2.05
2.02
2.33
< 2mm parts percentage
2-0.02 0.02-0.005 0.005-0.002 <.002
%
%
%
%
82
72
82
78
79
82
78
9
18
12
15
15
12
14
2
7
3
4
5
3
5
7
3
3
3
1
3
4
soil structure by
visual and feel
method
single grain / weak granular
single grain / weak granular
single grain / weak granular
single grain / weak granular
single grain / weak granular
single grain / weak granular
single grain / weak granular
single grain / weak granular
Effect of Compost on P Runoff Final Report
page
46
Appendix 2. Laboratory analyses for water samples analyzed in the study.
Sample
1-L-0
1-L-1
1-L-2
1-L-3
1-L-4
1-L-5
1-L-6
1-L-7
1-L-22
1-L-23
1-L-24
1-L-25
1-L-27
1-L-28
1-L-30
1-L-31
1-L-32
1-L-33
1-L-36
1-U-1
1-U-2
1-U-3
1-U-4
1-U-5
1-U-6
field upper (U)
plot lower (L) run†
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
U
U
U
U
U
U
0
1
2
3
4
5
6
7
22
23
24
25
27
28
30
31
32
33
36
1
2
3
4
5
6
Date
analysis
reported
3/10/95
3/27/95
5/3/95
5/3/95
5/3/95
5/15/95
5/15/95
5/15/95
6/9/95
6/9/95
6/9/95
6/9/95
6/9/95
6/9/95
6/9/95
6/9/95
6/9/95
6/12/95
6/12/95
3/27/95
5/3/95
5/3/95
5/3/95
5/15/95
5/15/95
analyzed in laboratory
derived measures
total
Acid
Occluded
Organic
reactive
digested
Total
NitrateP
P
P
P
P
nitrogen
Ac-P - TR-P T-P - Ac-P
TR-P
Ac-P
T-P
NO3-N
Oc-P
Or-P
––––––––––––––––––––––––––––– mg/L –––––––––––––––––––––––––––––––––––––––––
0.48
0.51
0.75
n.d.
0.03
0.24
0.06
0.07
0.23
n.d.
0.00
0.16
0.07
i.s.
0.07
n.d.
i.s.
i.s.
0.03
i.s.
0.07
n.d.
i.s.
i.s.
0.06
i.s.
0.11
n.d.
i.s.
i.s.
0.06
0.19
0.80
0.79
0.12
0.62
0.03
0.06
0.15
1.00
0.03
0.10
0.03
0.06
0.10
0.81
0.03
0.04
7.02
7.11
18.02
1.30
0.09
10.91
3.61
3.81
4.49
1.43
0.20
0.68
2.49
2.71
3.42
1.18
0.22
0.71
0.61
0.83
1.17
1.40
0.23
0.33
3.12
3.57
4.53
1.09
0.45
0.96
0.22
0.35
0.37
1.07
0.12
0.02
0.08
0.14
0.21
2.39
0.06
0.07
0.07
0.36
0.53
9.14
0.28
0.17
0.13
0.16
0.35
0.52
0.03
0.19
0.12
0.13
0.24
4.35
0.01
0.11
0.14
0.17
0.30
2.42
0.03
0.13
i.s.
i.s.
0.76
n.d.
i.s.
i.s.
0.03
i.s.
0.22
n.d.
i.s.
i.s.
0.08
i.s.
0.42
n.d.
i.s.
i.s.
0.05
i.s.
0.38
n.d.
i.s.
i.s.
0.06
0.08
0.19
0.81
0.02
0.11
0.11
0.12
0.29
0.81
0.01
0.17
Effect of Compost on P Runoff Final Report
page
47
Appendix 2. Laboratory analyses for water samples analyzed in the study.
Sample
1-U-7
1-U-22
1-U-23
1-U-24
1-U-27
1-U-28
1-U-30.31
1-U-32
1-U-33
1-U-36
2-L-1
2-L-2
2-L-3
2-L-4
2-L-5
2-L-6
2-L-7
2-L-22
2-L-23
2-L-24
2-L-25
2-L-26
2-L-27
2-L-28
2-L-29
field upper (U)
plot lower (L) run†
1
1
1
1
1
1
1
1
1
1
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
U
U
U
U
U
U
U
U
U
U
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
7
22
23
24
27
28
30-31
32
33
36
1
2
3
4
5
6
7
22
23
24
25
26
27
28
29
Date
analysis
reported
5/15/95
6/9/95
6/9/95
6/9/95
6/9/95
6/9/95
6/9/95
6/9/95
6/12/95
6/12/95
3/27/95
5/3/95
5/3/95
5/3/95
5/15/95
5/15/95
5/15/95
6/9/95
6/9/95
6/9/95
6/9/95
6/9/95
6/9/95
6/9/95
6/9/95
analyzed in laboratory
derived measures
total
Acid
Occluded
Organic
reactive
digested
Total
NitrateP
P
P
P
P
nitrogen
Ac-P - TR-P T-P - Ac-P
TR-P
Ac-P
T-P
NO3-N
Oc-P
Or-P
––––––––––––––––––––––––––––– mg/L –––––––––––––––––––––––––––––––––––––––––
0.03
0.06
0.23
0.95
0.03
0.17
5.53
5.68
14.24
1.57
0.15
8.57
3.45
4.14
5.69
0.69
0.69
1.55
2.84
3.30
4.06
1.31
0.47
0.75
1.54
1.76
2.33
2.42
0.22
0.57
0.20
1.35
2.03
0.60
1.16
0.68
2.20
2.35
2.87
0.49
0.16
0.52
0.14
0.35
0.40
0.44
0.20
0.05
0.11
0.14
0.26
1.42
0.03
0.12
0.17
0.33
0.44
1.05
0.16
0.11
0.19
0.19
0.57
n.d.
0.01
0.38
0.36
i.s.
0.43
n.d.
i.s.
i.s.
0.43
i.s.
0.52
n.d.
i.s.
i.s.
0.48
i.s.
0.53
n.d.
i.s.
i.s.
0.41
0.43
0.54
0.87
0.02
0.11
0.30
0.38
0.55
0.91
0.08
0.17
0.24
0.45
0.62
1.01
0.21
0.17
1.00
1.25
1.51
1.71
0.25
0.25
0.53
0.75
0.79
1.40
0.23
0.03
0.46
0.67
0.94
1.23
0.22
0.27
0.40
0.55
0.52
0.36
0.75
0.69
0.77
0.55
1.01
0.80
0.83
0.61
1.07
1.84
1.93
0.74
0.35
0.14
0.25
0.19
0.25
0.12
0.06
0.06
Effect of Compost on P Runoff Final Report
page
48
Appendix 2. Laboratory analyses for water samples analyzed in the study.
Sample
2-L-30
2-L-31
2-L-32
2-L-33
2-L-36
2-U-1
2-U-2
2-U-3
2-U-4
2-U-5
2-U-6
2-U-7
2-U-22
2-U-23
2-U-24
2-U-27
2-U-28
2-U-30.31
2-U-32
2-U-33
2-U-36
3-L-1
3-L-4
3-L-32
3-U-1
field upper (U)
plot lower (L) run†
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
3
3
3
3
L
L
L
L
L
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
U
L
L
L
U
30
31
32
33
36
1
2
3
4
5
6
7
22
23
24
27
28
30-31
32
33
36
1
4
32
1
Date
analysis
reported
6/9/95
6/9/95
6/9/95
6/12/95
6/12/95
3/27/95
5/3/95
5/3/95
5/3/95
5/15/95
5/15/95
5/15/95
6/9/95
6/9/95
6/9/95
6/9/95
6/9/95
6/9/95
6/9/95
6/12/95
6/12/95
3/27/95
5/3/95
6/9/95
3/27/95
analyzed in laboratory
derived measures
total
Acid
Occluded
Organic
reactive
digested
Total
NitrateP
P
P
P
P
nitrogen
Ac-P - TR-P T-P - Ac-P
TR-P
Ac-P
T-P
NO3-N
Oc-P
Or-P
––––––––––––––––––––––––––––– mg/L –––––––––––––––––––––––––––––––––––––––––
0.37
0.46
0.60
2.16
0.09
0.14
0.30
0.40
0.51
1.99
0.10
0.11
0.28
0.33
0.46
7.82
0.05
0.14
0.56
0.58
0.62
2.83
0.02
0.04
0.35
0.41
0.46
0.43
0.07
0.05
i.s.
i.s.
0.81
n.d.
i.s.
i.s.
0.45
i.s.
1.11
n.d.
i.s.
i.s.
0.15
i.s.
0.30
n.d.
i.s.
i.s.
0.20
i.s.
0.57
n.d.
i.s.
i.s.
0.24
0.31
0.32
0.89
0.07
0.01
0.03
i.s.
0.26
0.80
i.s.
i.s.
0.11
0.21
0.32
0.92
0.11
0.11
2.32
2.79
3.85
1.43
0.47
1.06
0.58
0.73
0.77
1.17
0.15
0.04
0.52
0.69
1.03
1.30
0.17
0.35
1.20
1.40
1.53
1.21
0.20
0.13
0.31
0.52
0.53
0.56
0.20
0.02
0.25
0.33
0.46
0.55
0.08
0.13
n.s.
n.s.
n.s.
n.s.
n.s.
n.s.
0.64
0.78
0.81
3.64
0.14
0.03
0.35
0.37
0.55
2.24
0.02
0.19
0.59
0.63
0.93
n.d.
0.04
0.31
0.32
i.s.
0.69
n.d.
i.s.
i.s.
1.04
1.28
1.37
1.03
0.24
0.10
0.54
0.59
1.69
n.d.
0.04
1.10
Effect of Compost on P Runoff Final Report
page
49
Appendix 2. Laboratory analyses for water samples analyzed in the study.
Sample
3-U-4
3-U-32
5-L-1
5-L-4
5-L-8
5-L-9
5-L-10
5-L-11
5-L-12
5-L-13
5-L-14
5-L-15
5-L-16
5-L-17
5-L-18
5-L-19
5-L-20
5-L-32
5-L-34
5-L-35
5-U-1
5-U-4
5-U-8
5-U-11.14
5-U-15
field upper (U)
plot lower (L) run†
3
3
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
U
U
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
U
U
U
U
U
4
32
1
4
8
9
10
11
12
13
14
15
16
17
18
19
20
32
34
35
1
4
8
11–14
15
Date
analysis
reported
5/3/95
6/9/95
3/27/95
5/3/95
5/15/95
5/15/95
5/15/95
5/15/95
5/15/95
5/15/95
5/15/95
6/9/95
6/9/95
6/9/95
6/9/95
6/9/95
6/9/95
6/9/95
6/12/95
6/12/95
3/27/95
5/3/95
5/15/95
5/15/95
6/9/95
analyzed in laboratory
derived measures
total
Acid
Occluded
Organic
reactive
digested
Total
NitrateP
P
P
P
P
nitrogen
Ac-P - TR-P T-P - Ac-P
TR-P
Ac-P
T-P
NO3-N
Oc-P
Or-P
––––––––––––––––––––––––––––– mg/L –––––––––––––––––––––––––––––––––––––––––
0.59
i.s.
1.76
n.d.
i.s.
i.s.
0.60
0.63
0.85
ND
0.03
0.22
0.19
0.20
0.44
n.d.
0.01
0.24
2.56
i.s.
3.30
n.d.
i.s.
i.s.
0.01
0.10
0.27
1.29
0.09
0.17
0.01
0.10
0.41
1.15
0.09
0.31
0.05
0.14
0.89
1.42
0.09
0.75
0.11
0.12
0.28
1.38
0.02
0.16
0.12
0.30
0.43
1.74
0.18
0.14
0.08
0.10
0.83
1.16
0.02
0.73
0.14
0.14
0.81
1.39
0.00
0.66
1.48
1.58
2.60
1.05
0.10
1.02
4.01
4.31
7.08
1.25
0.31
2.77
1.96
2.21
3.01
0.82
0.25
0.80
2.05
2.36
3.51
0.54
0.31
1.15
1.68
1.86
2.53
0.51
0.18
0.68
4.86
5.42
12.86
0.94
0.56
7.44
0.46
0.50
0.69
0.78
0.05
0.19
0.15
0.19
0.33
1.42
0.03
0.14
0.22
0.29
0.33
1.27
0.07
0.04
0.09
0.10
0.36
n.d.
0.01
0.26
0.16
i.s.
0.26
n.d.
i.s.
i.s.
0.03
0.24
0.66
1.38
0.21
0.43
0.03
0.51
0.99
0.95
0.49
0.48
1.53
1.87
2.94
2.69
0.34
1.07
Effect of Compost on P Runoff Final Report
page
50
Appendix 2. Laboratory analyses for water samples analyzed in the study.
Sample
5-U-16
5-U-17
5-U-18
5-U-19
5-U-20
5-U-32
5-U-34
5-U-35
6-L-1
6-L-4
6-L-8
6-L-9
6-L-10
6-L-11
6-L-12
6-L-13
6-L-14
6-L-15
6-L-16
6-L-17
6-L-18
6-L-19
6-L-20
6-L-21
6-L-32
field upper (U)
plot lower (L) run†
5
5
5
5
5
5
5
5
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
U
U
U
U
U
U
U
U
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
16
17
18
19
20
32
34
35
1
4
8
9
10
11
12
13
14
15
16
17
18
19
20
21
32
Date
analysis
reported
6/9/95
6/9/95
6/9/95
6/9/95
6/9/95
6/9/95
6/12/95
6/12/95
3/27/95
5/3/95
5/15/95
5/15/95
5/15/95
5/15/95
5/15/95
5/15/95
5/15/95
6/9/95
6/9/95
6/9/95
6/9/95
6/9/95
6/9/95
6/9/95
6/9/95
analyzed in laboratory
derived measures
total
Acid
Occluded
Organic
reactive
digested
Total
NitrateP
P
P
P
P
nitrogen
Ac-P - TR-P T-P - Ac-P
TR-P
Ac-P
T-P
NO3-N
Oc-P
Or-P
––––––––––––––––––––––––––––– mg/L –––––––––––––––––––––––––––––––––––––––––
6.22
8.64
21.00
2.46
2.42
12.36
2.62
3.11
4.33
0.17
0.49
1.22
5.95
6.19
15.49
0.29
0.24
9.30
n.s.
n.s.
n.s.
n.s.
n.s.
n.s.
3.49
5.20
5.85
0.97
1.71
0.65
0.86
0.97
1.17
1.08
0.11
0.20
0.19
0.49
0.54
0.82
0.31
0.05
0.15
0.39
0.42
2.11
0.24
0.03
2.17
2.26
13.78
n.d.
0.09
11.51
0.08
i.s.
0.42
n.d.
i.s.
i.s.
1.27
2.01
3.19
2.77
0.75
1.18
1.47
2.13
3.31
2.58
0.66
1.18
2.01
2.21
3.76
2.36
0.20
1.55
0.88
0.93
1.53
1.93
0.05
0.60
1.85
1.99
2.31
1.67
0.14
0.32
1.74
2.42
3.50
1.95
0.68
1.08
2.87
2.89
5.48
2.38
0.02
2.59
2.52
2.54
4.51
1.36
0.02
1.97
0.88
1.07
1.78
1.94
0.19
0.71
0.56
0.82
1.12
0.52
0.26
0.30
1.91
2.08
2.85
0.34
0.17
0.77
3.71
3.93
5.63
0.44
0.22
1.70
4.81
5.02
11.49
2.02
0.20
6.47
4.83
6.83
11.58
1.32
2.00
4.76
1.97
2.04
2.12
0.52
0.06
0.09
Effect of Compost on P Runoff Final Report
page
51
Appendix 2. Laboratory analyses for water samples analyzed in the study.
Sample
6-L-34
6-L-35
6-U-1
6-U-4
6-U-8
6-U-11.14
6-U-15
6-U-16
6-U-17
6-U-18
6-U-19
6-U-20
6-U-32
6-U-34
6-U-35
field upper (U)
plot lower (L) run†
6
6
6
6
6
6
6
6
6
6
6
6
6
6
6
L
L
U
U
U
U
U
U
U
U
U
U
U
U
U
34
35
1
4
8
11–14
15
16
17
18
19
20
32
34
35
Date
analysis
reported
6/12/95
6/12/95
3/27/95
5/3/95
5/15/95
5/15/95
6/9/95
6/9/95
6/9/95
6/9/95
6/9/95
6/9/95
6/9/95
6/12/95
6/12/95
analyzed in laboratory
derived measures
total
Acid
Occluded
Organic
reactive
digested
Total
NitrateP
P
P
P
P
nitrogen
Ac-P - TR-P T-P - Ac-P
TR-P
Ac-P
T-P
NO3-N
Oc-P
Or-P
––––––––––––––––––––––––––––– mg/L –––––––––––––––––––––––––––––––––––––––––
2.15
2.45
2.60
1.94
0.30
0.15
2.41
2.51
2.67
2.78
0.10
0.16
0.64
0.67
1.53
n.d.
0.03
0.87
0.77
i.s.
2.07
n.d.
i.s.
i.s.
0.63
1.23
2.34
2.73
0.60
1.11
0.85
0.99
1.31
1.94
0.15
0.32
1.76
2.14
2.71
5.04
0.39
0.57
1.56
1.86
2.60
0.55
0.30
0.74
1.41
1.79
2.53
0.23
0.38
0.74
0.72
0.92
1.12
2.76
0.20
0.20
0.91
1.07
3.06
0.94
0.16
1.98
n.s.
n.s.
n.s.
n.s.
n.s.
n.s.
1.71
1.98
2.08
1.51
0.27
0.10
2.40
2.65
2.85
1.17
0.25
0.20
4.08
4.13
4.28
1.34
0.06
0.15
† see Table R-1 for explanation of runs; runs that contain more than one number are continuous through several runs
Effect of Compost on P Runoff Final Report
page 52
Appendix 3. S ummary statistics for solution chemistry analyses
analyzed in laboratory
derived measures
total
Acid
Occluded
Organic
reactive digested
Total
NitrateP
P
P
P
P
nitrogen
Ac-P - TR-P T-P - Ac-P
Sample plot U/L TR-P
Ac-P
T-P
NO3-N
Oc-P
Or-P
–––––––––––––––– average concentration (mg/l) –––––––––––––––––––
control
1
L
0.97
1.26
1.89
2.06
0.12
0.96
control
1
U
1.10
1.64
2.18
1.05
0.27
1.11
amended 2
L
0.42
0.57
0.68
1.86
0.14
0.15
amended 2
U
0.52
0.81
0.88
1.34
0.16
0.20
amended 3
L
0.65
0.95
1.00
1.03
0.14
0.20
amended 3
U
0.58
0.61
1.43
n.d.
0.04
0.66
control
5
L
1.12
1.17
2.26
1.13
0.14
1.02
control
5
U
1.78
2.52
4.50
1.29
0.60
2.37
amended 6
L
2.11
2.56
4.40
1.70
0.34
2.06
amended 6
U
1.45
1.77
2.37
1.82
0.25
0.63
–––––––––––––––– minimum concentration (mg/l) ––––––––––––––––––
control
1
L
0.03
0.06
0.07
0.52
0.00
0.02
control
1
U
0.03
0.06
0.19
0.44
0.01
0.05
amended 2
L
0.19
0.19
0.43
0.43
0.01
0.03
amended 2
U
0.03
0.21
0.26
0.55
0.02
0.01
amended 3
L
0.32
0.63
0.69
1.03
0.04
0.10
amended 3
U
0.54
0.59
0.85
n.d.
0.03
0.22
control
5
L
0.01
0.10
0.27
0.51
0.00
0.04
control
5
U
0.03
0.10
0.26
0.17
0.01
0.03
amended 6
L
0.08
0.82
0.42
0.34
0.02
0.09
amended 6
U
0.63
0.67
1.12
0.23
0.03
0.10
–––––––––––––––– maximum concentration (mg/l) –––––––––––––––––
control
1
L
7.02
7.11
18.02
9.14
0.45
10.91
control
1
U
5.53
5.68
14.24
2.42
1.16
8.57
amended 2
L
1.00
1.25
1.51
7.82
0.35
0.38
amended 2
U
2.32
2.79
3.85
3.64
0.47
1.06
amended 3
L
1.04
1.28
1.37
1.03
0.24
0.31
amended 3
U
0.60
0.63
1.76
n.d.
0.04
1.10
control
5
L
4.86
5.42
12.86
1.74
0.56
7.44
control
5
U
6.22
8.64
21.00
2.69
2.42
12.36
amended 6
L
4.83
6.83
13.78
2.78
2.00
11.51
amended 6
U
4.08
4.13
4.28
5.04
0.60
1.98
Effect of Compost on P Runoff Final Report
page 53
Appendix 3. S ummary statistics for solution chemistry analyses
analyzed in laboratory
derived measures
total
Acid
Occluded
Organic
reactive digested
Total
NitrateP
P
P
P
P
nitrogen
Ac-P - TR-P T-P - Ac-P
Sample plot U/L TR-P
Ac-P
T-P
NO3-N
Oc-P
Or-P
––––––––––––––––––––– standard deviation ––––––––––––––––––––––
control
1
L
1.8
2.0
4.2
2.3
0.1
2.7
control
1
U
1.7
1.9
3.6
0.6
0.3
2.4
amended 2
L
0.2
0.3
0.3
1.8
0.1
0.1
amended 2
U
0.6
0.8
0.9
0.9
0.1
0.3
amended 3
L
0.4
0.5
0.3
0.1
0.1
amended 3
U
0.0
0.0
0.5
n.d.
0.0
0.6
control
5
L
1.5
1.6
3.2
0.3
0.1
1.8
control
5
U
2.3
2.9
6.8
0.9
0.8
4.3
amended 6
L
1.3
1.4
3.8
0.8
0.5
2.9
amended 6
U
1.0
1.0
0.9
1.4
0.2
0.6
–––––––––––––––– number of samples analyzed –––––––––––––––––––
control
1
L
19
16
19
14
16
16
control
1
U
15
12
16
12
12
12
amended 2
L
19
16
19
15
16
16
amended 2
U
14
10
15
11
10
10
amended 3
L
3
2
3
1
2
2
amended 3
U
3
2
3
n.d.
2
2
control
5
L
18
17
18
16
17
17
control
5
U
12
11
12
10
11
11
amended 6
L
19
18
19
17
18
18
amended 6
U
12
11
12
10
11
11