Strand = Biology
The Sustainability of Ecosystems

Last Date of Revision: Oct 4

Overall Expectations

1. demonstrate an understanding of the dynamic nature of ecosystems, including the relationship between ecological balance and the sustainability of life;
2. investigate factors that affect ecological systems and the consequences of changes in these factors;
3. analyse issues related to environmental sustainability and the impact of technology on ecosystems.

Specific Expectations

Understanding Basic Concepts

describe the processes of photosynthesis and cellular respiration as they relate to the cycling of energy, carbon, and oxygen through abiotic and biotic components of an ecosystem (e.g., explain that photosynthesis and cellular respiration are essentially reverse processes, and identify the reactants and products of their overall reactions);
illustrate the cycling of matter through biotic and abiotic components of an ecosystem by tracking nitrogen;
explain the process of bioaccumulation and assess its potential impact on the viability and diversity of consumers at all trophic levels;
examine the factors (natural and external) that affect the survival and equilibrium of populations in an ecosystem (e.g., resource limits of an ecosystem, competing populations, bioaccumulation, selective decline);
examine how abiotic factors affect the survival and geographical location of biotic communities (e.g., explain why deserts exist in different parts of the world);
explain why different ecosystems respond differently to short-term stresses and long-term changes (e.g., short term: the activity of tent caterpillars during a season; long-term: the effect of acid rain on maple trees);
compare a natural and a disturbed ecosystem and suggest ways of assuring their sustainability (e.g., compare a meadow and a lawn);
explain how soil composition and fertility can be altered in an ecosystem and identify the possible consequences of such changes.

Developing Skills of Inquiry and Communication

formulate scientific questions about observed ecological relationships, ideas, problems, and issues (e.g., “What impact will supplying an excess of food for a particular organism have on an ecosystem?”);
demonstrate the skills required to plan and conduct an inquiry into ecological relationships, using instruments, apparatus, and materials safely and accurately, and controlling major variables and adapting or extending procedures where required;
select and integrate information from various sources, including electronic and print resources, community resources, and personally collected data, to answer the questions chosen;
analyse data and information and evaluate evidence and sources of information, identifying flaws such as errors and bias;
select and use appropriate vocabulary and numeric, symbolic, graphic, and linguistic modes of representation to communicate scientific ideas, plans, results, and conclusions (e.g., use terms such as biotic, abiotic, biomass, biome, ecosystem, chemical concentration, and biodiversity when making presentations);
design and conduct an investigation to examine the effects of one factor on soil composition and fertility and on water quality in an ecosystem (e.g., design and conduct an experiment to examine the effects of altering soil pH on the fertility of plants and on the concentration of dissolved oxygen in water, and graph the results);
analyse a population case study (e.g., of deer, wolves, or humans) by producing population growth curves for each of the populations in the study, and use the graphs to explain how different factors affect population size and to predict the effect of varying factors (e.g., the availability of food) on the population.

Relating Science to Technology, Society, and the Environment

assess the impact of technological change and natural change on an ecosystem (e.g., the introduction of fertilizer and pesticides to soil; the introduction of a genetically engineered plant or the effect of polluted water or air on plants and animals; the effect on an ecosystem of forest fire, flood, the natural infection of one species, or the movement of a species in or out of the area);
describe ways in which the relationships between living organisms and their ecosystems are viewed by other cultures (e.g., First Nations);
identify and research a local issue involving an ecosystem; propose a course of action, taking into account human and environmental needs; and defend their position in oral or written form (e.g., organize and participate in a debate on converting a grass lot into a parking lot);
describe the physical and chemical processes involved in the methods used to clean up a contaminated site (e.g., how absorbent chemicals such as charcoal work in cleaning up oil spills);
identify and evaluate Canadian initiatives in protecting Canada’s ecosystems;
explain changes in popular views about the sustainability of ecosystems and humans’ responsibility in preserving them (e.g., the shift from a belief that all resources are inexhaustible to the belief that recycling, reusing, and reducing are important);
describe careers that involve knowledge of ecology or environmental technologies, and use resources such as the Internet to determine the knowledge and skill requirements of such careers.

An Outline of Topics Covered in This Strand

1. Diversity in Ecosystems
2. Change and Stability in Ecosystems
3. Sustaining Terrestrial Ecosystems
4. Sustaining Aquatic Ecosystems