Ecology - Advanced Honor

Nature Study

Requirements

1. Have the Ecology Honor.

   Answer: You must have completed the Ecology honor (regular) before starting the Advanced one. The regular one covers the fundamentals: definition of ecology (the study of the relationships between living beings and the environment), basic concepts (ecosystem, habitat, niche), food chain and web, cycles of matter (water, carbon, nitrogen), common environmental problems. — Ecology was created as a science by Ernst Haeckel in 1866 — "oikos" (house) + "logos" (study). The regular version provides the vocabulary and concepts that underpin the advanced study. Without understanding the basic ecosystem, advanced concepts (trophic levels, energy flow, the laws of thermodynamics applied) remain too abstract without context.

2. Define the following terms:
   • Raw material;
   • Photosynthesis;
   • Chemosynthesis;
   • Autotrophic;
   • Heterotrophic;
   • Ecological balance;
   • Saprophages;
   • Decomposers;
   • Producer;
   • Consumer;
   • Limiting factor.

   Answer: 1) Raw material: a basic, unprocessed substance that serves as a starting point for the production of other materials or compounds. 2) Photosynthesis: the process by which plants (and other chlorophyll-bearing organisms) produce their food and energy from sunlight, CO2 and water. 3) Chemosynthesis: the process by which certain bacteria produce energy and food from the oxidation of inorganic chemical compounds, without needing light. 4) Autotrophic: a living being capable of producing its own food (such as plants, by photosynthesis, or bacteria, by chemosynthesis). 5) Heterotrophic: a living being that does not produce its own food and nourishes itself by feeding on other organisms. 6) Ecological balance: a state of stability and dynamic equilibrium of an ecosystem, in which populations and resources are maintained in relatively constant proportions. 7) Saprophages: organisms that feed on dead or decomposing organic matter. 8) Decomposers: beings such as bacteria and fungi that decompose dead organic matter, recycling nutrients back to the environment. 9) Producer: an autotrophic organism (such as plants) that is at the base of the food chain and produces its own food. 10) Consumer: a heterotrophic organism (animals) that feeds on producers or on other consumers. 11) Limiting factor: an element or condition (water, light, food, space, temperature, etc.) whose scarcity restricts the growth or survival of a population. — Ecology terms interconnect: producers (autotrophs) perform photosynthesis; consumers (heterotrophs) eat producers; decomposers (saprophages) recycle dead matter. Chemosynthesis occurs in oceanic hydrothermal vents — bacteria that live without sunlight. A limiting factor (water, nutrient) defines how far a population can grow in a region.

3. Explain what trophic levels are and give examples of organisms for each level.

   Answer: TROPHIC LEVELS: a position in the food chain according to feeding. Level 1 = PRODUCERS (plants, algae — they perform photosynthesis). Level 2 = PRIMARY CONSUMERS (herbivores: cow, grasshopper). Level 3 = SECONDARY (carnivores that eat herbivores: frog). Level 4 = TERTIARY (carnivores that eat carnivores: snake, hawk). DECOMPOSERS (bacteria, fungi) act at all levels. — Energy is LOST between trophic levels — only ~10% passes from one level to the next (the 10% rule). That is why ecological pyramids have a triangular shape (few at the top, many producers). Decomposers are not in the linear chain — they recycle all the levels. A sustainable system needs a balance between levels so as not to collapse.

4. State the first and second laws of thermodynamics and explain how they are important for ecology.

   Answer: 1st LAW (CONSERVATION): energy is neither created nor destroyed, only transformed. 2nd LAW (ENTROPY): in any transformation, part of the energy DEGRADES into heat (loss). Importance in ecology: they explain why the food chain has a loss of ~90% between levels (entropy) and why ecosystems need a CONSTANT flow of solar energy to keep functioning. — The 1st law says that the energy from the sun that enters an ecosystem = the energy that leaves (transformed). The 2nd law says that part becomes useless heat — hence the ecological pyramid narrows. Without continuous solar energy, the ecosystem would collapse from entropy. This also explains why top carnivores (hawk, lion) are ALWAYS fewer in number than herbivores, always.

5. Present a diagram that contains the basic steps of the flow of energy through the biotic system of an ecosystem. Start the diagram with the sun.

   Answer: Diagram: SUN → PRODUCERS (plants via photosynthesis, capture ~1% of the light) → PRIMARY CONSUMERS (herbivores, receive ~10% of the energy from the plants) → SECONDARY CONSUMERS (carnivores, receive ~10% from the herbivores) → TERTIARY CONSUMERS (~10% of the secondary) → DECOMPOSERS (at all levels, recycle organic matter). Show arrows indicating a unidirectional flow. — The 10% rule shows the massive loss of energy between levels — that is why a sustainable ecosystem has thousands of plants for each hawk. Decomposers close the cycle of matter (not of energy — energy is lost as heat). The diagram should use thick arrows at the beginning (more energy) tapering as you climb the trophic levels of the ecosystem.

6. Make a diagram of the three types of ecological pyramids that exist in the food web. Present at least one example in each layer of the pyramid.

   Answer: There are 3 types of ecological pyramids: 1) PYRAMID OF NUMBERS — represents the quantity of individuals at each trophic level (e.g.: base = many plants/grass, then many grasshoppers, then few frogs, top = very few hawks); it can become inverted (one tree supports thousands of insects). 2) PYRAMID OF BIOMASS — represents the total mass of living matter per level, generally g or kg per area (e.g.: base = 1000 kg of plants, then 100 kg of herbivores such as cows, then 10 kg of carnivores, top = 1 kg of predator); it can also invert in aquatic environments (phytoplankton). 3) PYRAMID OF ENERGY — represents the flow of energy (kcal/m²/year) per level; it is ALWAYS triangular and never inverts, due to the 10% rule (only about 10% of the energy passes from one level to the next, e.g.: producers 10,000 kcal → herbivores 1,000 → carnivores 100 → top 10). In each layer there must be at least one example of an organism (producer, primary, secondary and tertiary consumer). — The pyramid of numbers can INVERT in some situations (one huge tree feeds thousands of insects). Biomass can also invert in aquatic ecosystems. But the pyramid of energy is ALWAYS triangular — the second law of thermodynamics does not allow another form. That is why it is the most scientifically useful for analyzing ecosystems.

7. Explain what biochemical cycles are and make a diagram of all the basic components of the cycle.

   Answer: BIOCHEMICAL (or biogeochemical) CYCLES: the cyclical path that chemical elements (C, N, O, P, H₂O) travel between living matter (biota) and non-living matter (atmosphere, soil, water). Components: RESERVOIR (atmosphere, ocean, soil) + EXCHANGES (biological/geological transformations) + FLOW (movement between reservoirs). Examples: the carbon, water, nitrogen cycle. — Without biogeochemical cycles, life would cease — essential elements (C, N) would be consumed and not replenished. The carbon cycle involves photosynthesis (the plant absorbs CO₂), respiration (releases it), fossil combustion (human interference). A typical diagram shows arrows joining the reservoirs atmosphere ↔ biota ↔ soil ↔ ocean with transformations at each interaction.

8. Fulfill one of the items below:
   • Choose a biological community in your region, such as a forest or woodland, swamp, lake or reservoir, pasture or field, ravine or stream, etc., that is in some way ecologically altered. Describe the location, including how the balance was disturbed and to what extent. Then, present recommendations on how that community can be improved and direct your efforts toward following up and helping with the improvement work;
   • Actively participate in an ecological project. This can be done individually or in a group. Prepare an outline of the project and its objectives, as well as report in detail the part you played in it.

   Answer: Choose an option: (1) IDENTIFY an altered community (a degraded forest, a polluted lake, an eroded pasture), describe how/how much it was altered, propose improvements and FOLLOW the recovery work. OR (2) ACTIVELY PARTICIPATE in an ecological project (reforestation, river cleanup, selective collection), describing the objectives and YOUR specific contribution. — Both options require PRACTICAL ACTION — theory alone is not enough. Reforestation of degraded areas has a high impact. In an altered community, proposing an improvement involves a diagnosis (the cause of the problem) + a plan (species to plant, erosion control) + execution. Photographic documentation before/after is evidence of the effective contribution to the project carried out.

9. Find a passage from the Spirit of Prophecy and a Bible text, different from those used in the Ecology honor, related to ecology and explain their relevance and application to our days.

   Answer: Research NEW texts (not used in the regular honor). BIBLICAL: Romans 8:19-22 (the whole creation groans awaiting redemption), Psalm 24:1 ("the earth is the Lord's, and everything in it"), Proverbs 12:10 (the righteous care for the life of their animals). SPIRIT OF PROPHECY: "Education" ch. 7 (nature as a book), "Thoughts from the Mount of Blessing" (the lilies of the field). Cite with the full reference. — Romans 8:22 says that "the whole creation has been groaning as in the pains of childbirth" — it shows that nature was damaged by sin and awaits restoration at the Second Coming. Ellen White in "Education" shows nature as a REVELATION of God complementary to the Bible. Adventists have a strong tradition of environmental care linked to faith since Ellen White in the 1800s.