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BIOS1301 – Ecology and SustainabilityModule 1 – Introduction to Ecology and Sustainability - Ecology is the study of interactions between organisms and their environment.  Study of the relationships, distribution and abundance of organisms, or groups of organisms in an environment. - Natural select...

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BIOS1301 – Ecology and Sustainability Module 1.1 – Introduction to Ecology and Sustainability - Ecology is the study of interactions between organisms and their environment.  Study of the relationships, distribution and abundance of organisms, or groups of organisms in an environment. - Natural selection – Charles Darwin 1859  Environment favours individuals with certain genotypes to survive well in certain habitats.  Survival of the fittest – contributions to the future population, and survivors fit their environment and transfers their genes into the population. - Environment  An environment could be defined as:  Intrinsic to an organism  Physiology, body requirements, behaviour  Extrinsic to an organism  Abiotic resources (light, temperature, water, topography)  Biotic factors (food availability, predators, competitors, mates)  Species specific definition  Changing spatial and temporal scales (movements, lifetimes)  Resources for species can be defined as anything used by an organism (e.g. minerals used by plants, plants - nesting material and food)  Levels of organisation  Organism – living organisms, fundamental units of populations and communities  Populations – group of individuals of a species living in one place at one time  Communities/ecosystems – assemblages of species populations occurring together in space and time  Landscapes – spatially connected parts of the environment - Ecosystems  An ecosystem is an interdependent community of organisms interacting with its local nonliving environment. It shares a commonality of processes (e.g., energy flow and chemical cycling).  Can apply to areas of all sizes and functions (e.g. rainforests, coral reefs, wetland) and be artificial or natural) and useful for observation and study).  Biodiversity  Genetic variability  Species richness (no. of species)  Species diversity (no. of species and abundance)  Functional diversity (relative number of different functional organisms)  Gradient diversity (speciation of ecological equivalents)  Community diversity (number, sizes and spatial distribution of communities)  Landscape diversity  Food webs  Ecologists divide the species in a community or ecosystem into different trophic levels based on the main source of nutrition.  Trophic level of an organism is the position it occupies in a food web.

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Population  Structure of populations consist of gains (e.g. birth, immigration) and losses (e.g. death, emigration) and its dynamics (e.g. increasing, stable or decreasing) Community  Co-existence of species in space and time  Species composition in a community seldom in a stable state  Disturbance – physical and biological factors Biodiversity  Integration of biological variability across all scales, from the genetic, through species, and ecosystems  Loss of biodiversity – simplification of biological variability Primary producers  Autotrophs – photosynthetic plants  Support all other trophic levels either directly or directly  Synthesize organise food materials from inorganic food materials from inorganic precursors using solar energy  Base of primary production begins a trophic structure through which energy flows.

1.2 – Key Issues of Sustainability - Extinction o Anthropocene is a unit of geologic time, describing the most recent period in Earth’s history

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when human activity started to have a significant impact on the planet’s climate and ecosystems  Extinction of birds  127 named birds extinct (116 island endemics) over past 400 years  Humans responsible for 20% extinction  Once 13,000 species compared to 9,800 now  Extinction of fish species  Global fish catch increased six times between 1950 and 1997  Living Planet Index  Number of species decreased around 77-89% between 1970 and 2016. Extinction rates

 Background rate (fossil record)  (0.1-1 species per thousand per thousand years)  (i.e. for every thousand species, one became extinct in every period of a thousand years)  Current rate based on recent extinctions is 1,000 times the background rate  Projected future rate is up to 10,000 times the background rate. o Impact of Biodiversity loss  Regulate ecosystems for the benefit of humans i.e. ecosystem services  Biodiversity loss implicated in direct impacts on human societies, usually poor societies  Utilitarian values (medicines, pollination, water and air quality) Human Populations o World population is exponentially increasing with >7 bn people – LCD 6bn, DC 1bn. o

Global birth and death rates

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 Birth/death rates decreasing, gap shows natural increase in human population.  Less people, less environmental impact  Increase in women’s education  smaller family sizes in LDC  Population growth in Australia is increasing – migration is a factor. Effect of Humans on the Environment o

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Diet  Humans have a unique, broad and expanding food niche  Ranges from carnivory to obligate herbivory  No other species consumes such a range  Increasing human populations and consumption (food, fibre, water, energy) Human pressure on natural resources

 Water (freshwater, seawater), land (surface, underground) and air have all been affected by pollution by humans, which negatively impacts global sustainability.  Increasing loss, degradation and fragmentation of natural ecosystems. o Human implicated in mass extinctions Taxonomy of Threats Affecting the Environment o o

Habitat loss Invasive species

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Climate change

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Overexploitation/harvesting Pollution

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Disease

Case Study 1: New chameleon species found (30/1/21) - Environmental problem o seaf and need to identify the biodiversity of the world -

Role of environmental science o Discovery and cataloguing the world’s animals, plant and other species o Identifying characteristics that define them as species o

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New chameleon species, potentially world’s smallest reptile found in Madagascar

 Likely endangered by forest clearing Management o Protection in national parks o Ensure other threats such as climate change and invasive species do not impact.

1.3 – Definitions of Sustainability - Understanding Sustainability  

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Sustainable development is development that meets the needs of the present without compromising the ability of future generations to meet their own needs. Intergenerational equity is the issue of sustainable development referring, within the environmental context, to fairness in intertemporal distribution of the endowment with natural asset or of the rights to their exploitation. The Earth Summit  UN conference on environment and sustainable development  June 13, 1992 in Rio de Janeiro, Brazil  Over 30,000 participants and over 188 heads of state

Agenda 21: Themes  The prospering, just, habitable, fertile, shared, clean and peoples’ world – all human centred goals.  Successes:  Public awareness, interest from private industry, slight improvements of problems addressed and foundation of international cooperation.  Failures:  International funding, national commitment and solid leadership.  Sustainable development goals  2030 agenda for sustainable development (Sep 2015)  17 SDGs implemented on 1 Jan 2016 over 15 years, founded on MDGs  Applies to all countries and non-legally binding.  Gaia Hypothesis – James Lovelock 1979  All living things on earth (biosphere) function as one superorganism that changes its environment to create conditions that best meet its needs, with the ability to self-regulate critical systems needed to sustain life.  Global waste  By 2075 – world population to reach 9.5  World currently produces 4 billion tonnes of food per annum  30-50% estimated not to reach human stomach (1.2-2 billion tonnes)  Energy and waste  US has 5% of world population and consumes 20% of world energy  Each item of food on American plate travelled an average of 2,400 km  25-33% of dairy and vegetable; 16% of meat is wasted each year  Average American family spends $600 on food never eaten each year  Discarded food in the US in 2007 equivalent to 350 million barrels of oil, about double Switzerland annual energy use Ecological definition 

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Why are we not sustainable?  Resource scarcity  Lack of technology  Environmental problems  Mass consumption  Poverty and third world  Uneven wealth  Conflict between nations  Lack of public awareness  Falling standards  Uncertainties  Riddled economic system Energy  Energy production contributed 68% of Australia’s greenhouse gas emissions in 2002 (predicted 72% in 2020).  47.6% of energy emissions come from Stationary energy and coal combustion accounts for 92% of electricity emissions Definitions of sustainability 

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Coal industry  Economics security and prosperity  Social development and advancement  Environmental sustainability Forestry

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Tasmania’s State forests will be a globally trusted source of sustainable timber and other forest products and services for this and future generations o About half of Australia’s forests cleared or severely modified o Significant ecosystems for birds, mammals and many plants o

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Biodiversity increases with forest age

Sustaining: o Biodiversity and habitats o Jobs for current and future generations o

Carbon stores, clear air, water and healthy forests

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Community access and heritage Science-based stewardship

The role of economics  There is a tension between market economics and environmental sustainability  Key economic indicators  Gross National Product (GNP)  Total value of final goods and services produced in a year by a country (including profits from capital held abroad)  Per person measures a country’s wealth  Gross Domestic Product (GDP)  Total value of final goods and services produced within an economy within a country’s borders in a year.  Failures of economic indicators  Do not measure environmental degradation  Environmental disasters increase GDP because of the work generated  Emphasis on quantity not quality  Do not measure volunteer services  Need an economic indicator that measures ecological sustainability  Genuine progress indicator (GPI)  Other indices of quality of life  Gini (wealth distribution) – lower = equality  Human Development Index  Happy Planet Index  Natural capital  Any stock of natural resources or environmental assets, that yield a flow of useful goods and services now and in the future (e.g. trees, animal, soils and water)  Economic drivers  Until recently, only manufactured stocks were considered as capital  The economy was very small in relation to natural processes New values  Domination of nature becomes ecological sensitivity  Consumerism replaced by quality of life  Individualism  human solidarity  Re-defining sustainability  Sustainability: a state in which the environment and its ecosystems are not degraded by human activities

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Development: evolution of increasing human welfare and well-being Sustainable development (SD): development which does not degrade environment and its ecosystems over the long term (50-100 years)

Case Study 2: Impacts of Mining on Macarthur River (8/2/21) -

Environmental problem o Diversion of river by 5km to access zinc underneath riverbed o Pollution impacts

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Effect on the environment o River and water quality impacts o o

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Effect on fish, turtles and dugongs Effects on Traditional Owner communities

Role of environmental science o identify likely impacts o Measurement of hydrological and water quality variables Policy and Management o Protection o

Regulation and prosecution

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Restoration

1.4 – Environmental Science Environmental science is the study of everything in the world around us, the impact of humans on the environment, the management of human activities for sustainability and is interdisciplinary. - Science  What is science?  Science helps us understand the environment  Scientific ideas change (new observations can modify theories)  Scientific knowledge is durable  Science does not give absolute truth (theories are mostly correct)  Science cannot answer all questions.  Science principles  Specific causes for observed events which can be identified  General rules can describe observations  Repeated events have same cause, perceptions not individualistic  Fundamental rules of nature are universal.  Concepts in science  Model – explanations of observed patterns. Can be verbal or numerical models. Usually relate a response variable to a predictor variable.  Theory – well-founded body of related hypotheses and models that form a selfconsistent description of nature.  Scientific reasoning  Deduction  Hypothetico-deductive approach  Derivation of explanations or predications from laws or theories.  Induction  Confirmatory approach

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Sufficient observations ‘confirm’ a theory is true Science grows by the accumulation of well-tested facts grounded in observation – empiricism o If events observed under many conditions and all have a particular property, then by induction all events have the particular property. o Bayesian inference – estimate probability of a hypothesis occurring based on prior evidence. Problems with induction: o Justification not possible based on experience or uniformity – leads to circular reasoning o No measure of the level of support for an inductive statement.

Falsification  Theories come from anywhere and the complete truth cannot be established by the methods used to develop them.  No amount of evidence can verify that a theory is true  To be a scientific, a theory must be capable of falsification  Problems with falsification: o Hypotheses or theories are never subjected to experimental tests o o o o

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in isolation Auxiliary hypotheses are always relied on Any idea can be saved provided we adjust our auxiliary hypotheses Scientists do not reject theories when they do not agree with observations or facts Accepted hypotheses (i.e. not falsified) are corroborative.

Scientific Method  Key elements of scientific method:  Observation  Question/model  Hypothesis: logical statement that potentially explains or answers a question/event  Considers all known facts  Simple as possible  Testable and falsifiable  Data collection and analysis  Conclusion  Three approaches for the scientific method: 1. Theoretical approach  Models and simulations for predictions 2. Comparative approach  Data from different groups (individuals, species, sites) that vary in a few factors as possible (e.g. juveniles vs adults) 3. Experimental approach  Manipulative experiment where factors are varied to test the hypothesis. Involves a control with only one different between them and repeated to eliminate unconscious bias or spurious correlation.

Case Study 3: Dam Collapse in the Himalayas (India) (8/2/21)

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Environmental problem o Climate change melting glaciers and affecting rivers with dams Role of environmental science o Increasing temperature rises with climate change melting glaciers in the Himalayas o

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Dams built on rivers to control flows

 Major impacts on river ecosystems, affecting biodiversity  Impacts on downstream communities – 150 people missing Policy and Management o Reduction in emissions – reduce temperatures o Reduce number of dams on rivers so that floods can be absorbed by freshwater ecosystems

Module 2 – Biodiversity and Landscape Processes: 2.1 Biodiversity -

The variety of all living things, the genetic information they contain and the ecosystems they form. Biodiversity explored at three levels: o Genetic diversity o Species diversity o

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Ecosystem diversity.

These three levels work together to create the complexity of life on Earth. Biodiversity and Technology o Examples of such relationships include:  Zoology – infrared and sonar technology  Photosynthesis – solar panels  Insects – hearing technology  Worm Nervous systems – artificial intelligence  Mammalian brain – computer and microchip technology

Case study 4: The Value of Biodiversity – the Naked Mole Rat o Investigating phylogenetic relationships o

Made an important observation that made rodent species readily get tumours however, the naked mole rat did not.  The naked mole rate is the longest living rodent (30 years)  Sparked an interest in their tumour suppression strategies  Anti-cancer mechanisms (tumour defence)

Australian Biodiversity Compared to the Globe - Endemic: exclusively native to a place or biota, in contrast to cosmopolitan or introduced. - Biodiversity within Australia vs Named Species o Invertebrates (47% vs 30%)

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Fungi (42% vs 10%)

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Plants (9% vs 70%) Vertebrates (1% vs 90%)

Reasons for the uniqueness of Australia’s biodiversity o Isolation  Biogeography is the study of patterns of distribution of plants and animals in time and space together with the factors causing those patterns.

Plate tectonics – continental drif Gondwanaland linked continents  Divergence of mammals – marsupials and monotremes compared with placentals  Wallace’s Line  Separates Oriental biota from Australian biota  Distinct species’ distribution  Reflect continental processes  2600 individuals  First described as a fossil in 1895, found 70 years later Findings

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Later rediscovered in high alpine areas, underground in boulder fields Distribution: restricted above the winter snowline in NSW and VIC Abundance: 30M years  Infertile, unproductive, weathered soils  Low nutrients – nitrogen and phosphorous; found in top 5cm  Infertile soil – old, eroded, limited soil formation  Flora adaptation to low nutrients

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Climate and rainfall  Low and variable rainfall  75% semi/arid, rainfall  drives plant productivity and diversity o Boom and bust cycles

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 Variable climate – inland climate is highly variable (species are adapted) Water resources  Flat, old poor drainage  Sandy soils – low runoff  Lack of permanent fresh water Fauna/flora

 Endemism – 90% mammals  Inverts – 250,000 species  Plants – 86% Land Degradation o Definition

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 Decline in productivity/condition caused by disturbance or use – soil focused  Natural/human accelerated  Affects: (i) culture/society/economy and (ii) ecosystems/functions/species/climate  Interactions are interconnected between soil, plants and animals Landscape function  Functioning landscape - an ecosystem that retains and effectively uses resources (i.e. water and nutrients), which translates into productivity of plants, then flows onto animals.  Rain follows patchy empty terrain then hits vegetation, infiltrates into soil -> positive feedback cycle -> bands of vegetation forming -> productivity increases

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Soil structure  Compaction of soil removes pores – affects infiltration of water (surface sealing; h2O drops  crusting) which leads to erosion  Soil erosion  Wind - soil and fertility loss, root exposure, dust clouds – affect plants  Water – soil/plants, flooding, water quality, salinity Land use in Australia  

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Vegetation clearing (60% cleared)  erosion...