Learning objectives
The module Ecology aims at providing and improving the basic knowledge on the main topics of modern ecology, along with its evolution in the last century in relation to the main environmental issues. Students are expected to achieve the capacity of analysing ecosystem structure and process and to address the main ecological issues of sustainable environmental management, natural resources exploitation and nature conservation.
The student is expected to achieve the basic knowledge in the various fields of general ecology: adaptation of organisms to the environment, population and community ecology, structure and ecosystem processes.
The ability to use ecological concept and data to solve simple problems is achieved with exercises carried out under the teacher supervision as well as with examples of ecological applications to environmental issues.
Prerequisites
Basic knowlegde acquired in the first year.
Course unit content
This course is divided into five parts.
The first part deals with on how ecology can contribute at solving environmental problems, e.g. management and conservation of natural resources and environmental processes.
In the second part the ecosystem is presented as the basic unit for the analysis of environmental systems, with reference to energy flows and biogeochemical cycles.
In the third part, the community is presented as a result of the biotic interactions between populations, with special reference to inter-specific competition and predation. Special attention is then paid to the food web theory.
The fourth part is dedicated to population ecology, with particular reference to structure, dispersal, growth and limiting factors.
The fifth part addresses the relationships between organisms and environmental conditions, focusing on habitat, niche, stress and tolerance concepts.
Full programme
PART 1. BASIC CONCEPTS AND HISTORY OF ECOLOGY.
What ecology deals with. Ecology and environmentalism. The onset of the environmental problem versus the development of ecology. Challenges for ecology in the 21st century.
PART 2. ECOLOGY OF THE ECOSYSTEM.
Hierarchical organization of ecological systems and emergent properties. Spatial and time scales in ecology.
Ecosystem: unifying concept of ecology.
2.1. Ecosystem structure
Abiotic components and factors. The water cycle. Water, thermal properties and functioning of aquatic ecosystems. Water and climate.
Energy and ecological systems: relevance and role of ultraviolet, visible and infrared radiation. Interactions between radiation and atmospheric gases.
Chemical factors and main environmental matrices: atmosphere, hydrosphere, lithosphere/pedosphere and biosphere. Elemental composition of matrices and ecological role of elements with atomic numbers <30.
2.2. Biotic components and factors: relations with energy and matter
Energy acquisition by photosynthetic organisms: limiting factors, resource allocation, adaptations to environmental conditions.
Energy acquisition of heterotrophic organisms (outline).
2.3. Ecosystem processes
Energy flow and conceptual models of energy analysis. Elton: food cycle, Lindeman: trophodynamic model, Odum: hydraulic model.
The representation of the flow of energy: pyramids of numbers, biomass and energy. Food web concept: grazing and detritus food webs. Criticisms to the tropho-dynamic model. Metabolic theory.
The carbon cycle as a link between the abiotic world and the living system. Primary production and decomposition: reactions, processes and limiting factors.
Biogeochemical cycles. Fundamental cycles in model ecosystems: tropical rainforest, deciduous continental forest, lake and agro-system.
Main biogeochemical cycles: nitrogen, phosphorus, silicon, iron and sulfur. Self-regulation of ecosystems: biogeochemical buffer capacity.
PART 3. COMMUNITY ECOLOGY.
3.1. The community is the biotic component of ecosystem resulting from interactions between populations. Species composition: Simpson and Shannon indices. Trophic organization and structure. Trophic networks. Effects of limitation: trophic cascade interactions, top-down and bottom-up regulation. The stress as a destructuring factor. Adaptive responses. The intermediate disturbance hypothesis.
3.2. Time evolution: ecological succession. Biogeographic approach. The pioneer and climax phases of succession: relationships between production, respiration and biomass (P/B, P/R). Factors that drive the succession: energetic, trophic, competition, facilitation.
Perturbations, resilience, resistance and regime shift (outline).
PART 4. POPULATION ECOLOGY.
4.1. Populations and meta-populations. Sampling methods. Exponential growth. Resource limitation, intraspecific competition and logistic growth. r and K strategies.
4.2. Interactions between populations. Interspecific competition: exclusion and coexistence. Lotka Volterra equations. Predator-prey interactions. Prey defences against predators. Optimal foraging. Other biological interactions (outline): mutualism, symbiosis, parasitism.
PART 5. ORGANISMS AND ENVIRONMENT
Habitat theory. Ecological niche: ecological responses at the single organism level. The fitness concept. Biological and ecological traits: functional, life history, effect/response traits. Mass hypothesis ratio. Stress and adaptation.
Bibliography
Recommended Textbook: Pusceddu A., Sarà G., Viaroli P., 2020. Ecologia. UTET Università, Novara (in Italian).
Additional materials provided by the lecturer will be downloadable from the Elly web page of the course
- slides the lectures as pdf documents
- booklet with a summary of the lectures and a critical discussion of the main topics
- open access reports and pubblication for individual activities by students.
Teaching methods
All educational activities will be carried out in the classroom. Three main activities will be organized in accordance with the University rules to contrast the COVID19 pandemic
-lectures by the teacher
-review activities and exercises
Assessment methods and criteria
After completing this course the student is able to understand and analyze the main characteristics of ecosystem structures and related processes. This background enables the student to deal with environmental problems with different levels of complexity.
The exam is organised in a written test to be held in a classroom. The test is composed of short questions, open questions and exercises. The exam is passed with score 18; the maximum score is 35; score >32 corresponds to 30 cum laude. Students who pass the test are admitted to the exam of the second module on “Analysis of ecological systems".
Other information
The module "Ecology" is integrated with the module "Analysis of ecological systems" (prof. Giampaolo Rossetti). The two modules are evaluated with two distinct tests. After passing the exam of the module "Ecology" the student can take the exam of the module "Analysis of ecological systems". The final grade is the average of the votes of the two exams.
