I am happy to thank Eric Hedger for video taping the hikes for me to view. I am also indebted to Angie Hudson and Bethany Keller for supplying me with the data accumulated on the hikes.
|Table of Contents||iii|
|List of Tables and Figures||iv|
|Materials and Methods||3|
|LIST OF TABLES|
|1||Relative Abundance and Frequency of Fauna||5|
|2||Relative Abundance, Frequency, and Relative Density of Herbs||7|
|3||Hardness, pH, and Chlorosity of Water||11|
|LIST OF FIGURES|
|1||Maple Creek Map||4|
|2||Relative Density of Shrubs||6|
|3||Percent Composition of Trees||8|
|4||Basal Area of Trees||9|
|5||Dissolved Oxygen Content in Water||10|
|6||Chemical Content and pH of Soil||12|
Perdue, Gina N. 1 June 1998. Studies of the Maple Creek ecosystem composition at UC Clermont College.
Baseline information of the Maple Creek ecosystem was obtained. A map of the primary creek was constructed using azimuth, length, and width measurements. Flora and fauna was identified and counted. Tree pairs were identified and the length and diameter at breast height was measured, Water and soil was analyzed for pH and chemical content. A secondary creek was found to run off the primary creek, Morels were found along the side of the creek. An ash-black cherry-locust forest was found to provide a thick canopy for a variety of flora and fauna that were found to flourish in the dark and moist growing conditions. The pH and chemical content of the water was found to be neutral and within normal limits. The pH and chemical content of the soil was found to be significantly different at the beginning of the primary creek than at the middle and end (indicating the start of alterations in the ecosystem).
In the study of ecosystems, the focus is often on the effect humans have on biodiversity. Frequently overlooked is the threat that reduction in biodiversity poses to human health (Kilbourne, 1998). Plant life can provide natural sources of chemicals found in many medications. For example, the foxglove plant is responsible for the invention of digitalis medications used to treat congestive heart failure. Equally fascinating is the array of natural chemicals found in animals. For example, neurologically active alkaloids from the poison dart frog have the potential for human therapy. Protecting biodiversity in ecosystems, therefore, is crucial to protecting human life. Protecting biodiversity begins with studying the biotic and abiotic factors that make up the ecosystem.
Ecosystems consist of plants, animals, and environmental factors, such as climate, unique to a specific area. In this study, the Maple Creek ecosystem will be explored to gain baseline information about its distinct composition. The flora and fauna will be surveyed for composition, the forest analyzed for diversity and amount of trees, and the soil and water analyzed for chemical composition. Baseline information is crucial in understanding the effects of future development on the Maple Creek ecosystem. Changes in flora, fauna, and chemical composition can alter the biodiversity that the ecosystem supports. By comparing the results of this study with the results of similar future studies, changes in biodiversity within the ecosystem can be found.
Past ecological studies, around the world, have focused on the effects of an alteration in one component of an ecosystem. One such study showed that human modification of natural streams disrupts the dynamic equilibrium between movement of water and the movement of sediment. This disruption alters the habitat and species composition (Poff, et al., 1997). Another study examined the role of climatic change in an ecosystem. Rain and snow patterns affect ecosystems by influencing factors ranging from food production to the frequency of floods (Monastersky, 1997).
To understand how changing biodiversity affects an ecosystem, ecologists must begin to look at how climate, water flow, and other environmental factors work together. Ecologists found that the impending sixth major extinction event in the history of life will be a result of many factors including: human impact on land use, species invasions, and atmospheric and climatic change. A recent study, looking at all these factors, showed that changes in human activity alter the types as well as the numbers of species (Sala, et al., 1998).
To gain a better understanding of the consequences of changing biodiversity, ecologists are beginning to turn to multi-scale studies. These multi-scale studies explore the relationships between all the components that make up an ecosystem. Now more than ever, ecologists must be prepared to develop more complicated explanations for ecological phenomena by incorporating processes that operate at many levels (Maurer, 1998).
A thorough study of changes in biodiversity in an ecosystem requires baseline information. Baseline data provides information on the variety of species, their numbers, habitats, and how all these are interrelated. Without these data there is no way of knowing what generates diversity, how it is changing, or how people are affecting the environment. An ecosystem's habitat has cycles; it does change. Ecologists need to focus now on how these changes occur over time (Morell, 1997).
A primary creek in the Maple Creek ecosystem was mapped on April 7 and 14, 1998. Starting at a drain, the length and width of straight segments were measured using a meter tape. Azimuth readings were obtained for each segment with a compass. From these data a map was constructed. Significant features were plotted on the map using distance and azimuth readings relative to points already plotted.
On April 21, 1998, insects, arthropods, and other animals were identified and counted at timed intervals. Relative abundance and frequency were calculated for each species. Four by four meter shrub plots and one by one meter herb plots in the Maple Creek ecosystem were surveyed on April 28, 1998. Shrubs, trees, herbs, and vines were identified and counted. Density, frequency, and relative density were calculated for each species.
Random pairs of trees in the Maple Creek ecosystem were analyzed on May 5, 1998. The distances between pairs of trees were determined using a meter tape. The diameter base height of each tree was measured using a tree tape. Calculations were performed to determine the total basal area per hectare of land and the composition of the trees.
Water samples from different parts of the primary creek in the Maple Creek ecosystem were analyzed on May 19, 1998. Three water samples were titrated with thiosulfate to determine the dissolved oxygen content. The pH of the water samples was determined using a pH meter. On May 26, 1998, three water samples were titrated with hydrochloric acid and calculations performed to determine the amount of calcium carbonate present. Calculations for the chlorosity of the samples were performed after titration with silver nitrate.
Soil samples from the Maple Creek ecosystem were analyzed on May 26, 1998. A LaMotte soil test kit was used to determine the pH and the nitrogen, phosphorus, and potassium content of the samples.
The primary creek in the Maple Creek ecosystem was mapped (figure 1). An unusual mushroom species, morels, was found near points 17, 18, and 23. A secondary creek runs off to the west at point 24.
The relative abundance (number of species noted per hour) and frequency (percent of plots containing species) of fauna found in the Maple Creek ecosystem is shown in table 1. Earthworms, pillbugs, and spiders were found in particularly high relative abundance and frequency.
|Table 1: Relative Abundance and|
Frequency of Fauna
The relative density of shrubs found in the Maple Creek ecosystem is shown in figure 2. Garlic mustard was noted to have a very high relative density.
The relative abundance, frequency, and relative density of herbs found in the Maple Creek ecosystem is shown in table 2. Cleavers, buttercups, Compositae, and violets were found in high numbers in all areas.
|Table 2: Relative Abundance, Frequency,|
and Relative Density of Herbs
|Purple Dead Nettle||10||75%||3.60%|
The percent composition of trees found in the Maple Creek ecosystem is shown in figure 3. Locust, black cherry, and ash trees made up most of the woodlands.
Basal area of wood (in m2) per hectare of land of trees found in the Maple Creek ecosystem is shown in figure 4. Ash trees provide the largest basal area of wood.
The dissolved oxygen content of three water samples taken from the primary creek in the Maple Creek ecosystem is shown in figure 5 The first sample was collected by the scouring rush (see figure 1). The other samples were collected from areas downstream.
The hardness of water (measured in amount of CaC03 present), pH level, and chloride content in water samples taken from the primary creek in the Maple Creek ecosystem is shown in table 3 The values were elevated for the sample taken by the scouring rush.
|Table 3: Hardness, pH, and Chlorosity of Water|
(g Cl-/L water)
The pH level and nitrogen, phosphorus, and potassium content of three soil samples collected in the Maple Creek ecosystem is shown in figure 6. Sample 17 collected by the scouring rush, had significantly different results than samples 2 and 3 (collected by the first dead tree and morels respectively).
Azimuth is the distance in angular degrees in a clockwise direction from north. Azimuth was determined by calculating the average of two readings taken 180° apart. Azimuth, distance, and width were used to map the primary creek in the Maple Creek ecosystem. Significant features of this ecosystem included morels and were plotted on the map. The map is an important part of the baseline information. Any changes in the water flow, caused by development in the area or climate, can change the size and shape of the creek and, consequently, the diversity surrounding it. Any future maps constructed would show these changes such changes in the creek.
A secondary creek runs to the west off the primary creek. Additional mapping of the secondary creek would be helpful in gaining a better picture of the ecosystem's water supply. Also, depth of the creek is important as an indicator of the type of aquatic biodiversity that the creek can support. Changes in the depth of a creek would be an important indicator of alterations in the ecosystem and should, therefore, be included in any future studies.
In the fauna survey conducted, earthworms, pill bugs, and spiders were all found in very high abundance and frequency, salamanders and flies were found in high abundance and moderately high frequency, and snails were found in moderate abundance and moderately high frequency. These findings were significant because all of the preceding species normally abide in areas that are dark, wet, and/or woody.
The results of the shrub survey indicated that garlic mustard was found in very high relative density. Garlic mustard, however, can flourish in almost any light or moisture level. The results of the herb survey was more interesting. Cleavers, buttercups, Compositae, and violets were found in high relative abundance, relative density, and frequency These plant species prefer dark and wooded surroundings. Moss was found in moderately high relative abundance, relative density, and frequency. Scouring rush was found in high relative abundance and relative density, but low in frequency. Moss and scouring rush are normally found in damp and dark areas.
Representative flora and fauna of the Maple Creek ecosystem could not survive in dry, sunny conditions. Changes in light levels, soil moisture, and/or water flow in the creek could alter the diversity of the existing flora and fauna that are dependent on the dark and moist conditions for survival, and result in their extinction. Any future surveys would detect alterations in the biodiversity present in the ecosystem. Future studies should include determination of dispersion of species found in the ecosystem.
The results of the tree analysis showed that the majority of the Maple Creek woodlands was composed of ash, black cherry, and locust trees. Therefore, the Maple Creek woodlands can be referred to as an ash-black cherry-locust forest. The Maple Creek woodlands was found to contain 1,000 trees and 563.72 m2 of wood per hectare of land. Ash trees provide the most wood per hectare of land in the Maple Creek ecosystem. The large amount of trees present provide the thick canopy that keeps the flora and fauna below well shaded. Alterations in the composition of the trees could affect the canopy and change the living conditions below it. Future studies could detect changes in the composition of the forest.
The tree analysis could be expanded by using transit readings to determine the height of the trees. Height and diameter at breast height could then be used to estimate the age of the trees found in the forest to determine whether or not the forest is newly established. A forest of relatively young trees, where old ones once resided, could be a result of alterations within the ecosystem. Future studies would show changes in tree ages and composition in an altered habitat due to surrounding land development.
The results of the water analysis showed that the dissolved oxygen content was slightly elevated toward the start of the primary creek, at the scouring rush, in the Maple Creek ecosystem. The primary creek runs downstream from the West Woods ecosystem--which is currently under development. Elevated dissolved oxygen is caused by churning and mixing of the water and could be resulting from alterations in the West Woods ecosystem. Although the dissolved oxygen content was higher at the scouring rush, the value was still within normal limits, as was the others. Further testing of additional samples would be needed to determine if the results were significant. The pH of the water in the primary creek was determined to be neutral.
The chlorosity of the water was found to be higher at the scouring rush. The calcium carbonate content at the scouring rush was also elevated, which could possibly indicate a slight increase in temporary hardness. Additional samples, taken near the drain in the primary creek would help determine if these results were significant, and if they could be caused by the surrounding land development.
The results of the soil analysis showed significantly different values for the scouring rush area than the dead tree and maple areas. The pH of the soil at the scouring rush was higher than the pH at the other two areas indicating the presence of more basic soil there. The nitrogen and phosphorus content was higher and the potassium content was lower at the scouring rush. The difference could be a result of the surrounding land development, but a future repeat study is needed to verify this. Additional testing of soil samples near the drain in the Maple Creek ecosystem would also help to verify this.
The difference in the soil type explains why scouring rush is only found in that area of the ecosystem. Future studies are needed to determine whether or not this is a new species to the ecosystem. The soil analysis results indicate that there are alterations occurring within the Maple Creek ecosystem. Future studies of the Maple Creek ecosystem will be needed to determine the affect of these alterations.
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Maurer, Brian A. 1998. Ecological science and statistical paradigms: at the threshold. Science. 279: 502-503
Monastersky, R. 1997. Continents growing wetter as globe warms. Science News. 152: 341.
Morell, Virginia. 1997. Counting creatures of the Serengeti, great and small. Science. 278: 2058-2060.
Poff, N. L., J. D. Allan, M. B. Bain, J. R. Karr, K. L. Prestegaard, B. D. Richter, R. E. Sparks, and J. C. Stromberg. 1997. The natural flow regime. Bioscience. 47(11): 769-782.
Sala, Osvaldo E., F. S. Chapin III, I. C. Burke, J. P. Grime, D. U. Hooper, W. K. Lauenroth, A. Lombard, H. S. Mooney, A. R. Mosier, S. Naeem, S. W. Pacala, J. Roy, W. L. Steffan, and D. Tilman. 1998. Ecosystem consequences of changing biodiversity. Bioscience. 48(1): 45-52.