Draft 2:Riparian Buffer Zone Diversity of Four Mile Creek and Collins Run

This topic submitted by Anne, Justin, Nikki, Sam ( etternm@muohio.edu ) on 10/9/03 .

Natural Systems 1 Syllabus---Western Program---Miami University

INTRODUCTION

Does the diversity of trees growing on a stream bank affect the health of the stream?

The purpose of this project is to determine whether the diversity of the trees in their height, canopy, and diameter has a direct affect on the health of the stream and the biodiversity of the macroinvertabrates. Our hypothesis is if the trees growing on a stream bank vary greatly in height, canopy size, species, and diameter, then the stream will be in good health. We plan to accomplish this by identifying the trees growing in the riparian buffer zone along the banks of Collins Run and Four Mile Creek. We will measure the heights, canopy size, and diameter of these trees using forestry tools, such as clinometers, diameter tape, tape measure, and instruments to measure canopy cover. We also plan on using data previously collected on the macroinvertabrate diversity living in the stream. We are planning on surveying three 10 meter square sections of the riparian buffer zone along the two streams. These sections are called headwater, mid river, lower reaches. This is interesting because there is no current data collected on the health of the riparian buffer zone for these two creeks in comparison of the stream life.

BACKGROUND INFORMATION

Oxford, Ohio is part of the Ohio River Valley which is highly polluted. For decades, factories in the Midwest have exposed forests in the area to high levels of acidic deposition. This acid rain creates severe climate stresses on the forests often causing the decline of weaker trees (1). Trees growing along the bank of a river or stream contribute to the riparian buffer zones or Òthe transition area from the aquatic to the uplandÓ (9). WebsterÕs New Universal Unabridged Dictionary (1978) defines riparius as a Latin word meaning Òof or belonging to the bank of a riverÓ (10). The buffer zone can range in width anywhere from 8m-100m depending on state-state laws based on the use of that stream (w3). These forests capture and store nutrient run-off preventing large amounts from polluting the water (2,3). Unfortunately, deforestation and developmet have caused a severe decline in adequate buffer zones. When deforestation occurs, succession will eventually replace the bank with grasses, which are also capable of trapping suspended sediments Ð sometimes even more efficiently than trees (5). However for the purposes of this lab, we only examine forest buffer zones.
Deforestation has caused water quality in streams in southwest Ohio to decline due to high rates of erosion and the associated nutrient run-off. Run-off fills streams with an overload of phosphorous and sediments causing eutrophication, high turbidity, and leading to a loss of diversity within the biocommunity. Besides as a buffer, trees growing along a stream bank also have other effects on the stream quality. The shade created by trees is beneficial to keeping stream temperature low. Cooler temperatures create high levels of dissolved oxygen that is essential for many aquatic organismsÕ survival (8). However too much shade can also be detrimental since it reduced the ability of under-story vegetation to get enough sunlight to photosynthesis (4,7). During the autumn season, trees drop their leaves with many blowing or falling directly into the stream. Macroinvertebrates living in the stream feed off of the leaves. Research has found that leaf consumption is greater with nitrogen enriched lives (6). Therefore the type of trees growing around the stream has an effect on the diets of aquatic organisms and directly determines which species can survive there (w2).
Development has a huge impact on the health of stream. Urbanization often causes sediments, nutrients, pesticides, and waste material (human and animal) in the form of non-point source pollution to collect upstream from the actual site of development due to run-off from paved roads or deforested areas (w1,w4). Macroinvertebretes or EPTs (ephemeroptera, plecoptera, and trichoptra) are studied to determine stream health in an area. Each type of insect lives in a different level of pollution and thus the abundance of one type can be viewed as a stream health determinant (12). A healthy stream habitat supports a diverse ecosystem. According to one article, ÒNatural riparian zones are some of the most diverse, dynamic, and complex biophysical habitats on the terrestrial portion of the planetÓ (11). Loss of this biodiversity leads to Òdiminished resistance and resilience to disturbance, system simplification, and loss of ecological integrityÓ (10).
Riparian buffer zones provide both public and private benefits in a community. The banks of streams, rivers, and lakes are high risk areas for development due to soil stability and erosion. The trees in a buffer zone work to hold soil in place and thus create stable banks and shorelines for building. As previously stated, the buffer zones also filter sediments, nutrients, and pollutants from run-off therefore maintaining good water quality for drinking water or other public use of the waterway (w5). Turbid waters causes water treatment companies to spend more money filtering and treating water than they would otherwise (w1). Shading keeps summer water temperatures cool creating a pleasant recreational retreat. Clean streams also provide better habitat for fish to live, grown, and spawn. The trees provide shelter for fish as well as wildlife which is beneficial both for hunting and aesthetic reasons (9). Therefore, it is important to study riparian buffer zones in order to protect and preserve local streams.

SOURCES

(1) LeBlanc, David C. ÒTemporal and spatial variation of oak growth-climate relationships along a pollution gradient in the Midwestern United States.Ó Canadian Journal of Forest Research 23 (1993): 772-82.
(2) Lucas, Michael F. and Medley, Kimberly E. ÒLandscape Structure and Nutrient Budgets in an Agricultural Watershed, Southwest Ohio.Ó Ohio Journal of Science (2002): 15-23.
(3) McLaughlin, Richard A. and Gilliarn, J. Wendell. ÒUsing natural and landscaped buffers to reduce pollutant loading from agricultural runoff.Ó Water Resources Research Institute of the University of North Carolina 34 (2002): 1-53.
(4) Bis, Barbara and Hilger, Lamberious W.G. ÒRiparian vegetation of streams and the macroinvertabrate community structure.Ó Ecohydrology of Hydrobiology 1 (2001): 253-260.
(5) Lyons, John; Trimble, Stanley W.; Paine, Laura K. ÒGrass verses trees: Managing riparian areas to benefit streams of Central North America.Ó Journal of the American Water Resources Association 36 (2000): 919-930.
(6) Irons, John G., III; Oswood, Mark W.; Bryant, John P. ÒConsumption of leaf detritus by a stream shredder: Influence of tree speices and nutrient status. Hydrobiologia 160 (1988): 53-62.
(7) Wilcock, Robert J.; Scarsbrook, Mike R.; Costley, Kerry S.; Nacols, John W. ÒControlled release experiemnets to determine the effects of shade and plants on nutrient rentation in lowland streams. Hydrobiologia 485 (2002): 153-162.
(8) Anonymous. ÒForest Relationship to Water Quality.Ó Kentucky Division of Water.
(9) Anonymous. ÒValues of Riparian Buffers.Ó
(10) Anonymous. ÒBiodiversity of Stream InsectsÓ Annual Reviews: Intelligent Synthesis of the Scientific Literature.
(11) Anonymous. ÒRiparian Zones and the Ecology of the Interfaces.Ó
(12) Anonymous. ÒRapid Bio-assessments of Benthic Macroinvertebrates in Urban Streams.Ó

WEBSITES

(w1) ÒIncentive Programs for Improving Environmental Quality.Ó Ohio State University Extension..
(w2) ÒLinking Riparian Tree Species Composition to Stream Faunal Diversity.Ó North American Benthological Society.
(w3) ÒDesign of Forest Riparian Buffer Strips for the Protection of Water Quality.Ó Analysis of Scientific Literature.
(w4) ÒConsiderations for Using Ecological Restoration: A Degraded Urban Watershed.Ó U.S. Environmental Protection Agency.
(w5) Virginia Cooperative Extentsion.

RESEARCH DESIGN

First we will measure out ten meter squared areas at the headwater, mid river, and lower reaches of the Four Mile Creek and Collins Run. At each site we will identify all the trees according to bark and leaf structure. Next, we will use a clinometer to measure the height of each of these trees. Then, we will use diameter tape to measure the diameter of each tree at breast height (which is four and a half feet). We will then measure the distance from the edge of the creek to the tree. Finally, we will measure the canopy cover at each location from the middle of the stream. Then we will analyze the data using the following data sheets:
Sheet 1
Sheet 2
Sheet 3
Sheet 4
Sheet 5
Sheet 6

MATERIALS

Diameter tape Ð
Diameter tape is used by wrapping the tape around the tree at breast height, 4 ¸ feet off of the ground. One must make sure to be on the uphill side of the tree when taking this measurement.
The importance of taking the diameter of the various trees is to show how large the trees are. Larger trees will act as a better buffer in taking in nutrients and holding soil from getting into the stream. These larger trees will act to show that the stream water should be in better health.

Clinometer Ð
Depending on which kind of clinometer one uses the individual must walk 66 or 100 meters from the base of the tree. Looking through the clinometer from this distance one must line up the line inside of the clinometer with the top of the tree. A number should be taken from this measurement. Next one must take another measurement looking at the tree one foot from the ground. This will give another number. By taking the number from the top of the tree and subtracting the number from the bottom of the tree one is able to find the height of the tree.
Finding the height of the tree is important in determining how tall all of the trees are around the stream. Taller trees will generally be larger trees. The larger trees will need more nutrients from the soil and will therefore act to better buffer the stream.

Instrument for measuring canopy cover Ð
The importance of measuring canopy cover over the stream is that it can show how much light reaches the water. Streams that receive more light will be more likely to grow aquatic vegetation of some kind. If the stream receives very little light due to a large canopy cover the stream will not be able produce as much aquatic vegetation. The stream with more aquatic vegetation will be a healthier stream because it acts as cover, and food for certain aquatic life. Another thing to consider with canopy cover is the foliage that gets dropped from the trees. With a greater canopy cover their will be a greater drop of leaves. These leaves will act as food for many of the organisms that live in the stream. The more canopy cover causes a greater drop of leaves into the stream which in turn causes a greater abundance of organism. This greater abundance of organism will act to make the stream healthier.

Tape measure Ð
To use a tape measure one must place one end at the end of the stream and walk with the tape until you reach the end of the buffer zone. Then one would put down the other end of the tape measure and read the number off of it. This would give the distance from the stream to the current object.
By measuring the distance of the trees from the stream one would be able to see how close the trees are to the water. The closer they are to the stream bank the more stable the bank will be. A more stable bank will slow erosion and lessen the amount of sediments in the water. This will make the water clearer and of healthier quality. The roots will also act as places for the fishes and other aquatic life to live and hide in. More trees closer to the stream means better health of the aquatic community.

CLASS INVOLVEMENT

The class will be given instructions on how to identify common trees by looking at the leaves. Each student will be given a tree identification sheet to use. By using many different factors found in the leaf structure the type of tree that it came from will be determined.

The factor that will be looked at first is the leaf stem arrangement. The leafs and branches will be arranged in either an alternating pattern, one on left then one on right, or in an opposite matter, both left and right at same spot on tree. Second, one will need to determine if the leaf is simple, compound, or double compounded. A simple leaf has a bud at the end of its stem. A compound leaf has several leaflets that join together on one stem with a bud at the end of that shared stem. A double compounded leaf is the same as a compound leaf only the leaflets have leaflets of their own. Next, one will need to look to see if the leaf has teeth, jagged edged, or is smooth. However when identifying a tree in the winter or late fall the tree will not have any leaves. In order to identify the tree one will first need to look to see if the branches are opposite or alternate. Next, the bark needs to be examined to determine the tree species. When looking at the bark on the tree one needs to always look towards the top of the tree as the bark lower on the tree often doesnÕt show the normal characteristics of the species tree. The bark of the tree is patterned depended on the tree species.

Tree Identification Guide

DATA SHEETS

RESEARCH TIMELINE

October 28 Ð Collins Run headwater
November 2 Ð Collins Run mid river
November 4 Ð Collins Run lower reaches
November 9 Ð Four Mile Creek headwater
November 11 Ð Four Mile Creek mid river
November 16 Ð Four Mile Creek lower reaches

RESULTS

DISCUSSION AND CONCLUSION

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