Week 8 Experiment Answer Sheet Please Submit To The Week 8 E

Week 8 Experiment Answer Sheetplease Submit To The Week 8 Experiment D

Please submit to the Week 8 Experiment dropbox no later than Sunday midnight.

Summary of activities for Week 8 Experiment assignment includes Exercise 1 – Species Interactions: Competition, and Exercise 2 – Biomes (Part I and II).

Paper For Above instruction

In this paper, I will comprehensively analyze the experimental procedures and findings related to species interactions, particularly competition, and examine biomes based on abiotic and biotic factors. The goal is to understand the dynamics of competition among microorganisms, how environmental factors define biomes, and the ecological principles underlying these phenomena.

Introduction

Ecological interactions such as competition significantly influence species population dynamics and community structure. Understanding how species compete for limited resources provides insights into their survival strategies and ecological niches. Additionally, biomes, characterized by distinctive climate patterns and flora, form the foundational ecosystems supporting diverse life forms. This paper integrates experimental data and theoretical concepts to elucidate these ecological processes.

Experiment 1: Species Interactions – Competition

The first exercise involved evaluating the effect of competition on two microorganism species, P. caudatum and P. aurelia, which compete for the same food source—bacteria. The experiment required setting up test tubes with each species grown separately and together, and monitoring their population changes over 16 days. The expected outcome, based on ecological principles, was that when grown separately, each species would reach its carrying capacity, while growth in the combined setup would showcase competitive interactions, potentially lowering the maximum populations due to resource limitations.

Data collection included counting microorganisms at regular intervals, multiplying counts to account for the sample volume, and plotting the results to visualize growth trends. These data helped in assessing the maximum population sizes (carrying capacity) and timing for each species in different conditions.

Results and Analysis

The graph comparison revealed that when grown separately, both P. caudatum and P. aurelia approached their respective carrying capacities, typically reached around day 10-12. In co-culture, population sizes were generally lower and exhibited delayed or suppressed growth, indicative of interspecific competition. The carrying capacity for each species in the combined culture was reduced, supporting the hypothesis that competition limits population growth.

Quantitative analysis showed a decrease in maximum cell concentrations for both species in the mixed culture compared to monocultures. The time to reach the maximum population was also prolonged, reflecting the competitive pressure exerted when resources are shared.

Discussion

The findings align with Lotka-Volterra competition models, illustrating that when two species compete for the same resource, their carrying capacities decline relative to when they are grown individually. The delayed growth and reduced maximum populations are consistent with resource partitioning and competitive exclusion principles.

This experiment underscores the importance of niche differentiation and resource availability in shaping community dynamics. It also demonstrates the capacity of microorganisms to compete efficiently under limited resources, influencing population stability and coexistence.

Biomes and Environmental Factors

The second exercise explored various biomes by analyzing abiotic factors such as temperature, rainfall, and other climate variables associated with specific geographic locations. The objective was to match these environmental parameters with the corresponding biomes and to understand the conditions that foster their development.

The locations, including Frogmore (England), Göteborg (Sweden), Koombooloomba (Australia), Barrow (Alaska), Alice Springs (Australia), San Bernardino (California), Centralia (Kansas), were assessed based on climate data. For instance, high rainfall and moderate temperatures aligned with temperate forest biomes, whereas arid conditions corresponded to desert biomes. These correlations were summarized in a table, with explanations linking the abiotic factors to the biome classifications.

Planting Sites and Biomes

In the second part, the selection of plant species such as creosote bush, spruce, flowering dogwood, orchid, lichen, bluestem grasses, white sage, and saguaro cactus was guided by the environmental conditions of their native biomes. For example, saguaro cactus was matched with desert biomes due to its adaptations to dry conditions, while flowering dogwood aligned with temperate forests owing to its preference for moist, well-drained soils.

Discussion and Ecological Principles

The exercise demonstrated how climate variables influence biome distribution and how specific plant adaptations enable survival in different environments. It emphasizes the concept of ecological niches and the importance of abiotic factors in community assembly. This understanding is crucial in predicting how climate change might shift biome boundaries and affect biodiversity.

Ecological Concepts and Principles

The discussion includes key ecological principles such as the distinction between K-selected and r-selected species. Typically, invasive species tend to be r-selected, producing many offspring rapidly, which facilitates their proliferation in new environments (Rejmanek & Richardson, 2013). The definitions of community and ecosystem are interrelated; communities comprise populations of different species interacting within an environment, while ecosystems include these biological communities and their abiotic surroundings, functioning as integrated units (Chapin et al., 2011).

Furthermore, the levels of ecological organization are correctly ordered as organism, population, community, and ecosystem, illustrating increasing complexity and scope (Odum, 2004). The concept of succession, exemplified by moss development on bare rocks, reflects primary succession, wherein life begins in lifeless areas (Connel & Slatyer, 1977). Human activities such as pesticide use can reduce population size and influence ecological balances, often leading to selection for resistant individuals via natural selection (Carson, 1962).

Energy Flow, Niche, and Population Dynamics

Energy transfer in ecosystems is predominantly through the biomass of autotrophs, with most energy lost as heat at each trophic level (Lindeman, 1942). Organisms occupy ecological niches that encompass their roles and resource use. Survivorship curves classify species' mortality rates over time; plants with few offspring surviving into maturity typically exhibit a Type III curve, while humans exhibit Type I (Southwood & Henderson, 2000).

The mutualistic relationship between algae and corals exemplifies positive interactions enhancing survival and reproductive success (Riegl & Pochon, 2002). Predation and competition serve as population regulation mechanisms, with weather being a classic example of a density-independent factor (Hunter & Price, 1992). Producers, mainly autotrophs like plants, form the foundation of food webs (Krebs, 2001).

Pollution, Bioaccumulation, and Economic Aspects

Biological magnification involves toxins accumulating higher concentrations in top predators, thereby impacting food webs and ecosystem health (Foott et al., 2009). Resistance to pesticides involves natural selection, where surviving insects pass resistant genes to offspring, increasing the frequency of resistance traits over generations (Georghiou & Taylor, 1986).

Conclusion

Understanding ecological interactions, community dynamics, and environmental conditions shaping biomes is essential for managing natural resources and conserving biodiversity. Experimental studies, as described, provide vital insights into these processes, informing ecological theory and practical conservation efforts.

References

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