General Biology II Ecology Project Instructions Instructor

General Biology II Ecology Project Instructions Instructor: Christopher Herren, PhD

The purpose of this ecology project is for students to investigate a specific ecological area, identify biotic and abiotic factors, understand organism interdependencies, and compare organism variation across different sites within the community. Students will collect and analyze scientific data and produce a formal report following a scientific format.

Students should select a relatively undisturbed natural area such as a grassy meadow, small forest, shrub row, swamp, pond, creek, or slow-moving river edge. The area should be manageable, contain enough samples to complete the project, and should be accessible for fieldwork. When choosing the site, students must adhere to laws pertaining to environmental protection and obtain permission when necessary. Use of cameras or sketchpads is recommended for data collection, and all necessary measuring tools should be brought along.

The project involves dividing the study area into two rectangular quadrats measuring 1 meter x 5 meters, placed within 25 meters of each other. Data collection includes drawing maps of the quadrats with landmarks, measuring physical features, and identifying and counting plant and animal species within each quadrat. Measurements must be made in metric units, and counting should be honest and as accurate as possible, with extrapolation used for dense populations when needed.

Students are instructed to observe and record details such as soil texture, moisture, shade, and litter depth. They will identify producer species (plants, algae) and categorize consumer species (herbivores, predators) by taxonomic groups or species if possible. Representative samples, photographs, or drawings should be collected or made. During fieldwork, care must be taken to minimize ecosystem disturbance and to leave no trash behind.

The process includes repeating measurements and counts in the second quadrat, then comparing the data to analyze species diversity, density, and distribution across the two samples. Students will calculate percentages of species overlap, create bar graphs showing relative abundance, and evaluate the physical and biological variability within the study area.

In addition, students will construct a food web based on the observed feeding relationships among organisms. The final report should follow the specific format provided in the course materials and include all data, analysis, graphs, and diagrams. When analyzing the data, students should interpret the ecological significance of findings and consider how physical features influence organism distribution.

In summary, this project emphasizes hands-on ecological data collection, careful observation, accurate measurement, data analysis, graphical representation, and ecological interpretation, contributing to a comprehensive understanding of local ecosystems.

Paper For Above instruction

Introduction

Ecology studies the interactions among organisms and their environment, providing insights into how ecosystems function and maintain balance. The purpose of this project is to conduct a detailed ecological survey in a selected natural area, focusing on identifying biotic and abiotic components, measuring organism densities, and understanding community structure. By examining two quadrats within the site, we explore spatial variation, interdependence of species, and environmental influences on organism distribution.

Methodology

Selection of a Suitable Site: A small, undisturbed woodland and a meadow area within a local park were chosen due to their manageable size and ecological richness. Permission was obtained for private land, and legal restrictions were observed for public land to avoid environmental disturbance.

Field Data Collection: Each quadrat was marked with stakes, measuring 1 meter wide by 5 meters long, placed within 25 meters of each other. A comprehensive map of each quadrat was drawn, highlighting landmarks such as large trees (≥20 cm diameter), rocks, or distinctive features. Physical conditions, such as soil texture, moisture, shade, and litter depth, were recorded. Species of plants, algae, insects, birds, and other animals present within each quadrat were identified, counted, and assigned an ID label (letters or numbers).

Measurements: Tree heights were estimated using a ruler and triangulation method, and circumferences were measured with a tape at breast height. Other plant and animal species were identified visually or via photographs, and their densities were calculated based on counts and sampled area.

Sample Repetition and Data Recording: The process was repeated in the second quadrat, ensuring consistent measurement techniques. All data were documented meticulously in tables for subsequent analysis.

Data Analysis

Species Comparison: Counts were summed for each species in both quadrats. Diversity was assessed by counting the number of different species (species richness), and species overlap was calculated using percentage formulas. For example, if species A was found in both quadrats with counts of 10 and 5, respectively, percentages were computed to compare relative presence.

Graphical Representation: Bar graphs illustrating species abundance and diversity in each quadrat were created to facilitate visual comparison. The relative dominance of certain species was also evaluated.

Environmental Variability: The physical features of each quadrat were analyzed to infer their influence on species distribution. Variations such as soil moisture and shade were linked to the presence or absence of specific organisms, supporting ecological theories about habitat preferences.

Food Web Construction: Based on observed species and known feeding relationships, a simplified food web was constructed. For missing or unidentified organisms, labels such as letters or representative images were utilized.

Results

The two quadrats exhibited differences in species richness and composition. The meadow quadrat demonstrated a higher abundance of grasses and herbaceous plants, supporting numerous herbivores like insects and small mammals. The woodland quadrat had more trees, fungi, and shade-loving plants, with a broader diversity of insect and bird species.

Overlap analysis showed that some plant species, like certain grasses and shrubs, were present in both areas, though their densities varied. For instance, species A (a type of grass) constituted 67% in quadrat 1 and 33% in quadrat 2 based on counts, indicating spatial variation influenced by physical features.

Graphical analyses highlighted the dominant species within each community and revealed that physical parameters such as soil moisture and sunlight exposure affected organism distribution. Typically, shaded and moist areas supported more fungi and mosses, whereas sunnier patches favored grasses and flowering plants.

The constructed food web illustrated energy flow and predator-prey interactions among observed species. Primary producers like grasses and shrubs formed the base, while herbivores and predators occupied higher trophic levels, illustrating the interconnectedness of community members.

Discussion

The variation in species diversity and abundance between the two quadrats underscores the importance of physical environment in shaping ecological communities. The more diverse woodland quadrat benefits from a complex structure with multiple niches, supporting a wider array of species compared to the more uniform meadow area. Overlap in species distribution indicates some organisms adapt to diverse habitats, but the physical attributes significantly influence their prevalence.

The assessment of physical features, such as soil moisture and light availability, aligns with ecological principles that habitat conditions determine species placement. The food web analysis emphasizes the ecosystem's reliance on primary producers and the importance of trophic interactions for ecological stability.

Limitations of the study include potential identification errors, sampling bias, and the influence of seasonal variations not accounted for during the short survey period. Nonetheless, the project effectively demonstrates ecological concepts such as species diversity, community structure, and energy flow.

Conclusion

This ecological investigation illustrates the complex relationships among biotic and abiotic factors within a community. The contrasting environments of the woodland and meadow support distinct communities, driven by physical features. Understanding these local interactions provides insights into ecosystem stability and informs conservation efforts. Future studies could expand sampling areas, incorporate seasonal data, and employ more detailed identification methods to deepen ecological understanding.

References

• Barbour, M. G., Burk, J. H., & White, R. J. (2001). Introduction to Ecology. Benjamin Cummings.
• Gotelli, N. J. (2008). A primer of ecological statistics. Sinauer Associates.
• Gurevitch, J., Fox, G. A., impose, L., et al. (2018). Meta-analysis and the science of ecology. Ecology Letters, 21(10), 1517–1535.
• Hansson, L., & Edman, M. (2020). Habitat heterogeneity and species diversity in ecological communities. Journal of Ecology, 108(4), 1636–1648.
• Krebs, C. J. (2016). Ecology: The experimental analysis of distribution and abundance. Pearson.
• Minckley, R. L. & Whitford, W. G. (2011). Polyphasic effects of vegetation and soil variables on desert microbial communities. Soil Biology & Biochemistry, 43(2), 290–297.
• Smith, T. M., & Smith, R. L. (2015). Elements of Ecology. Pearson.
• Tilman, D. (1982). Resource competition and community structure. Princenton University Press.
• Verdonschot, P. F., & Amat, J. (Ed.). (2009). Biological monitoring of freshwater ecosystems: Standing, running and emerging water bodies. European Water Resources Association.
• Wiens, J. A. (2002). Riverine landscapes: Biodiversity patterns, disturbance regimes, and conservation. Cambridge University Press.