Water Absorption Rateat the FSPA Organic Garden

Chris Pasquale and Eric Thuli

ABSTRACT

Permeability is defined as the ability of a porous mass to allow passage of water through the medium. Studying soil permeability means understanding the structure of the soil and how water passes through different layers. Determining permeability enables engineers and agriculturists to study fluid-flow characteristics through a soil mass and thus helps in improving the efficiency of the soil. Results help erect better structures, construct tables, and perform agricultural activities. The fluidity of soil depends upon various factors.

Absorption is really a factor of percolation as well as holding capacity of different soil type’s ability to store water. Percolation tests were conducted on soil of the FSPA garden and surrounding locations. The specific locations were; north and south garden, alfalfa field near the garden (alfalfa 1), alfalfa field far from garden (alfalfa 2), and the corn field. The gardens have received organic practices for the past 6 years while the alfalfa land has been in alfalfa for 5 years and is being transitioned to organic. The corn field has been conventionally farmed and rotated between soybeans, corn, and alfalfa. These observations allow us to hypothesize that the north and south garden will yield normal rates of water absorption, while the surrounding locations will have slower rates.

INTRODUCTION

The goal of this project was to determine the absorption rates of the soil at the FSPA garden. The reason behind this was to analyze the change of soil composition from previous years, determine the most suitable zones for planting, and to decide what needed to be done to the soil for more efficient growth. This research was done by an examination of absorption rates of the soil, or a soil percolation test.

EXPERIMENTAL DESIGN

RESULTS

DISCUSSION

The results revealed that alfalfa 1 had a surprisingly fast absorption rate, compared to alfalfa 2 and the corn field. Results of the north and south garden suggested that the soil had a faster than normal absorption rate. When compared to results of previous years, almost all matched besides alfalfa 1. Last year alfalfa 1 took over twenty four hours to complete the swelling period, while this year it only took around 2 minutes.

The soil of the FSPA area has been maintained by conventional and organic practices. The garden has seen organic fertilizers like compost tea, mycorrhizae fungi, and tilling. The surrounding area is heavy clay soil that has been brought up through conventional practices and has not seen any tilling. No till results in little incorporation of humus in soil which is essential for microbes and other living organisms and have a direct impact on water percolation and holding capacity of soil. Results suggest organic practices have had a positive effect in creating sustainable and livable land for crops to grow. To improve absorption, the transition from conventional to organic practices should continue.

FUNDING AND ACKNOWLEDGEMENTS

REFERENCES

ALFALFA 1

SOUTH GARDENNORTH GARDEN

CORN FIELD

ALFALFA 2

Special thanks to Viterbo University, Sr. Lucy, and the Franciscan Sisters of Perpetual Adoration

• American Society of Civil Engineers (ASCE), 1985, Manual 40 - Ground Water Management

• Soil Science Society of America (SSSA), 1975, Glossary of Soil Science Terms

• USGS, 1998, Ground Water and Surface Water - A Single Resource, USGS Circular 1139, Winter, T.C.,

• J.W. Harvey, O. L. Franke, and W. M. Alley• Soil Quality Test Kit Guide (USDA)

• Used a hollow metal cylinder, water, and a timer • The hollow metal cylinder was given a marking around the exterior at

two inches from the top (whichever side was chosen) with permanent marker

• The hollow cylinder was put into the ground up until the marking, exposing the two inches above ground

• The portion inside the cylinder was filled with 500mL of water in two sets. The first 500mL was done to allow the soil to become saturated, meaning to fill the voids between soil particles with water. The second 500mL was to cause soil swelling, the intrusion of water into individual soil particles.

• Both times the cylinder was covered with saran wrap to prevent evaporation

• The swelling period is when measurements were recorded and analyzed for absorption rates

• All 24 measurements occurred in 5 separate zones with two time trials in each zone