ENVS 205- module 2

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Module 2. Part A: The Socio-Ecological Crisis The first section will provide a basic background in environmental science helping you to understand the carbon cycle, the hydrological cycle and the nitrogen cycle. These biogeochemical cycles are critical for sustaining life on land and below water (SDG #15 & SDG #14). Section B weighs the current loss of biodiversity and explain its causes. Humans are the primary cause of extraordinarily high rates of species extinction, which we analyze in terms of the "anthropocene" in section C. Section D goes on to explain the socio-ecological crisis using a well-known I=PAT formula. In this formula, human impacts on the environment(I) are explained in terms of population growth (P), consumption or affluence (A) and technological developments (T). Icon for SDG 8. Decent Work and Economic Growth United Nations (n.d.) SDG #8 promotes economic growth, especially for low-income countries in the Global South. But is economic growth always a good thing? In Section E we appraise economic growth as a measure of wellbeing and suggest an alternative index. Using the I=PAT equation, section F examines the planetary limits on economic and population growth. We refine this analysis through the concept of "ecological footprint" in section G. In the final section we examine concepts from ecology and systems theory to help us better understand the processes that regulate (sustain) or change complex socio-ecological systems. Concepts we will cover include: feedback loops; equilibrium; and thresholds (also called limits, boundaries or tipping points). The Biosphere This is a derivative of the original, by Andrew Leakey, in chapter 6.2 of Sustainability: A Comprehensive Foundation . The Ecosystem Humanity and the natural world are inextricably linked. A growing appreciation for the importance of this fact led to the formation and publication of the Millennium Ecosystem Assessment by the United Nations in 2005. It defines key concepts necessary for understanding how sustainable development can be achieved. In the terms of the Assessment, an ecosystem is a dynamic complex of plant, animal, and microorganism

communities and the nonliving xenvironment interacting as a functional unit, while ecosystem services are "the benefits people obtain from ecosystems." Ecosystem services are critical to human well-being and sufficiently diverse and numerous to justify classification into four major categories: ● Provisioning ecosystem services are actively harvested by us from the natural world to meet our resource needs, e.g., food, water, timber, and fiber. ● Regulating ecosystem services are processes in the Earth system that control key physical and biological elements of our environment, e.g., climate regulation, flood regulation, disease regulation, water purification. ● Cultural ecosystem services reflect the aesthetic and spiritual values we place on nature, as well as the educational and recreational activities dependent on ecosystems. ● Supporting ecosystem services are the biogeochemical cycles, as well as biological and physical processes that drive ecosystem function, e.g., soil formation, nutrient cycling, and photosynthsis We benefit from the services associated with both pristine, natural ecosystems, such as tropical rain forests or arctic tundra, and highly managed ecosystems, such as crop fields or urban landscapes. In all cases, ecosystems contribute to human well-being by influencing the attainability of basic material needs (e.g., food and shelter), health (e.g., clean air and water), good social relations and security (i.e., sufficient resources to avoid conflict, tolerate natural and human-made disasters, provide for children, and maintain social cohesion), as well as freedom of choice and action (an inherent component of the other elements of well-being is the right to live as one chooses). Linkages between some ecosystem services and human well-being vary in strength depending on socio-economic status). For example, many people in developed countries can always afford to buy imported food without dependence on the yields of locally grown crops, thereby avoiding shortages when yields are low because of bad weather. However, in other cases our ability to control the impact of losing an ecosystem service on human well-being is limited. For example, despite major engineering efforts flooding still causes considerable human and economic damage in developed countries. The challenge of sustainable development stems from the need to benefit from and manage ecosystem services without causing damage to the ecosystems and Earth system that will reduce their value in the longer term. People have long recognized that some ways of using natural resources are unsustainable, especially where ecosystems are rapidly exploited to the maximum extent possible and further access to the ecosystem services can be achieved only by moving on to previously unexploited areas, as in the case of slash and burn agriculture. Only more recently have we come to appreciate that human activity is altering global-scale phenomena, such as climate regulation, and this understanding raises a host of difficult questions. That is because the benefit of an ecosystem service may be realized by people in one locale, while the costs (in the form of negative environmental consequences) are imposed on people who live elsewhere, and who may be less equipped to withstand them.

Biogeochemical Cycles and the Flow of Energy in the Earth System Fluxes- Transformations or flow of materials from one pool to another in a biogeochemical cycle. If humans are to live sustainably we will need to understand the processes that control the availability and stability of the ecosystem services on which our well-being depends. Chief among these processes are the biogeochemical cycles that describe how chemical elements (e.g., nitrogen, carbon) or molecules (e.g., water) are transformed and stored by both physical and biological components of the Earth system. Storage occurs in pools , which are amounts of material that share some common characteristic and are relatively uniform in nature, e.g. the pool of carbon found in soil or forests or as carbon dioxide (CO 2 ) in the atmosphere (see Figure 1 ). Transformations or flows of materials from one pool to another in the cycle are described as fluxes ; for example, the movement of water from the soil to the atmosphere resulting from evaporation is a flux. Physical components of the earth system are nonliving factors such as rocks, minerals, water, climate, air, and energy. Biological components of the earth system include all living organisms, e.g. plants, animals and microbes. Both the physical and biological components of the earth system have varied over geological time. Some landmark changes include: ● the colonization of the land by plants (~400 million years ago), ● the evolution of mammals (~200 million years ago), ● the evolution of modern humans (~200 thousand years ago) and ● the end of the last ice age (~10 thousand years ago). The earth system and its biogeochemical cycles were relatively stable from the end of the last ice age until the Industrial Revolution of the eighteenth and nineteenth centuries initiated a significant and ongoing rise in human population and activity. Today, anthropogenic (human) activities are altering all major ecosystems and the biogeochemical cycles they drive. Many chemical elements and molecules are critical to life on earth, but the biogeochemical cycling of carbon, water, and nitrogen are most critical to human well-being and the natural world. The Natural Carbon Cycle Most of the carbon on Earth is stored in sedimentary rocks and does not play a significant role in the carbon cycle on the timescale of decades to centuries. The atmospheric pool of CO2 is smaller (containing 800 GtC [gigatonnes of carbon] = 800,000,000,000 tonnes) but is very important because it is a greenhouse gas. The sun emits short-wave radiation that passes through the atmosphere, is absorbed by the Earth, and re-emitted as long-wave radiation. Greenhouse gases in the atmosphere absorb this long-wave radiation causing them, and the

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atmosphere, to warm. The retention of heat in the atmosphere increases and stabilizes the average temperature, making Earth habitable for life. More than a quarter of the atmospheric CO2 pool is absorbed each year through the process of photosynthesis by a combination of plants on land (120 GtC) and at sea (90 GtC). Photosynthesis is the process in which plants use energy from sunlight to combine CO2 from the atmosphere with water to make sugars, and in turn build biomass. Almost as much carbon is stored in terrestrial plant biomass (550 GtC) as in the atmospheric CO2 pool. On land, biomass that has been incorporated into soil forms a relatively large pool (2300 GtC). At sea, the phytoplankton that perform photosynthesis sink after they die, transporting organic carbon to deeper layers that then either are preserved in ocean sediments or decomposed into a very large dissolved inorganic carbon pool (37,000 GtC). This is one reason that oceans are considered a carbon "sink." Plants are called primary producers because they are the primary entry point of carbon into the biosphere. In other words, almost all animals and microbes depend either directly or indirectly on plants as a source of carbon for energy and growth. All organisms, including plants, release CO2 to the atmosphere as a by-product of generating energy and synthesizing biomass through the process of respiration. The natural carbon cycle is balanced on both land and at sea, with plant respiration and microbial respiration (much of it associated with decomposition, or rotting of dead organisms) releasing the same amount of CO2 as is removed from the atmosphere through photosynthesis. Definitions greenhouse gases Gases in Earth's atmosphere that absorb long-wave radiation and retain heat. primary producers The primary entry point of carbon into the biosphere—in nearly all land and aquatic ecosystems plants perform this role by virtue of photosynthesis. Respiration Metabolic process in all organisms that generates energy and synthesizes biomass while releasing CO2 as a by-product The Carbon Cycle, Explained The emissions of C02 through respiration and decomposition are generally balanced by photosynthesis and air-sea gas exchange (with the ocean absorbing some surplus CO2). The problem is that due to emissions caused by the extraction of fossil fuels from the fossil pool, in addition to land-use change and cement production, humans have caused a net increase per year in CO2 or greenhouse gas emissions. And in fact, this is increasing every year. Since carbon stays in the atmosphere for 20-200 hundred years before dissolving into the ocean, each

year humans are adding to the atmosphere pool of carbon. This is causing global warming. Figure 1 illustrates the carbon cycle on, above, and below the Earth's surface. Numbers in brackets represent constant storage pools of carbon at any given time measured in gigatons (Gt). Annual fluxes or flows of carbon are represented in white and red and measured in Gt/year. Human Interactions with The Carbon Cycle Definitions anthropogenic CO2 emissions Human release of CO2 into the atmosphere by burning fossil fuels and changing land use. land use change Human change in the use of land, e.g. deforestation or urbanization. The global carbon cycle contributes substantially to the provisioning ecosystem services upon which humans depend. We harvest approximately 25% of the total plant biomass that is produced each year on the land surface to supply food, fuel wood and fiber from croplands, pastures and forests. In addition, the global carbon cycle plays a key role in regulating ecosystem services because it significantly influences climate via its effects on atmospheric

CO2 concentrations. Atmospheric CO2 concentration increased from 280 parts per million (ppm) to 412 ppm between the start of industrial revolution in the late eighteenth century and 2022. This reflected a new flux in the global carbon cycle—anthropogenic CO2 emissions— where humans release CO2 into the atmosphere by burning fossil fuels and changing land use. Fossil fuel burning takes carbon from coal, gas, and oil reserves, where it would be otherwise stored on very long time scales, and introduces it into the active carbon cycle. Land use change releases carbon from soil and plant biomass pools into the atmosphere, particularly through the process of deforestation for wood extraction or conversion of land to agriculture. In 2009, the additional flux of carbon into the atmosphere from anthropogenic sources was estimated to be 9 GtC—a significant disturbance to the natural carbon cycle that had been in balance for several thousand years previously. Slightly more than half of this anthropogenic CO2 is currently being absorbed by greater photosynthesis by plants on land and at sea (5 GtC). However, that means 4 GtC is being added to the atmospheric pool each year and, while total emissions are increasing, the proportion absorbed by photosynthesis and stored on land and in the oceans is declining (Le Quere et al., 2009). Rising atmospheric CO2 concentrations in the twentieth century caused increases in temperature and started to alter other aspects of the global environment. Global environmental change has already caused a measurable decrease in the global harvest of certain crops. The scale and range of impacts from global environmental change of natural and agricultural ecosystems is projected to increase over the twenty-first century, and will pose a major challenge to human well-being. The Natural Water Cycle Definitions evapotranspiration Evaporation from vegetated land that includes water transpired by plants as well as evaporation from open water and soils. surface runoff Flow of water over the land surface. streamflow Flow of water in streams. infiltration Flow of water from the land surface into soils and rocks. groundwater discharge Flow of water from below-ground into rivers, lakes, or the ocean. The vast majority of water on Earth is saline (salty) and stored in the oceans. Meanwhile, most of the world's fresh water is in the form of ice, snow, and groundwater. This means a significant fraction of the water pool is largely isolated from the water cycle. The major long-term stores of fresh water include ice sheets in Antarctica and Greenland, as well as groundwater pools that

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were filled during wetter periods of past geological history. In contrast, the water stored in rivers, lakes, and ocean surface is relatively rapidly cycled as it evaporates into the atmosphere and then falls back to the surface as precipitation. The atmospheric pool of water turns over most rapidly because it is small compared to the other pools (e.g., <15% of the freshwater lake pool). Evaporation is the process whereby water is converted from a liquid into a vapour as a result of absorbing energy (usually from solar radiation). Evaporation from vegetated land is referred to as evapotranspiration because it includes water transpired by plants, i.e. water taken up from the soil by roots, transported to leaves and evaporated from leaf surfaces into the atmosphere via stomatal pores. Precipitation is the conversion of atmospheric water from vapour into liquid (rain) or solid forms (snow, hail) that then fall to Earth's surface. Some water from precipitation moves over the land surface by surface runoff and streamflow, while other water from precipitation infiltrates the soil and moves below the surface as groundwater discharge. Water vapour in the atmosphere is commonly moved away from the source of evaporation by wind and the movement of air masses. Consequently, most water falling as precipitation comes from a source of evaporation that is located upwind. Nonetheless, local sources of evaporation can contribute as much as 25-33% of water in precipitation. Human Interactions with The Water Cycle Freshwater supply is one of the most important provisioning ecosystem services on which human well-being depends. By 2000, the rate of our water extraction from rivers and aquifers had risen to almost 4000 cubic kilometres per year. The greatest use of this water is for irrigation in agriculture, but significant quantities of water are also extracted for public and municipal use, as well as industrial applications and power generation. Other major human interventions in the water cycle involve changes in land cover and infrastructure development of river networks. As we have deforested areas for wood supply and agricultural development we have reduced the amount of vegetation, which naturally acts to trap precipitation as it falls and slow the rate of infiltration into the ground. As a consequence, surface runoff has increased. This, in turn, means flood peaks are greater and erosion is increased. Erosion lowers soil quality and deposits sediment in river channels, where it can block navigation and harm aquatic plants and animals. Where agricultural land is also drained these effects can be magnified.

Urbanization also accelerates streamflow by preventing precipitation from filtering into the soil and shunting it into drainage systems. Additional physical infrastructure has been added to river networks with the aim of altering the volume, timing, and direction of water flows for human benefit. This is achieved with reservoirs, weirs, and diversion channels. For example, so much water is removed or redirected from the Colorado River in the western United States that, despite its considerable size, in some years it is dry before reaching the sea in Mexico. We also exploit waterways through their use for navigation, recreation, hydroelectricity generation and waste disposal. These activities, especially waste disposal, do not necessarily involve removal of water, but do have impacts on water quality and water flow that have negative consequences for the physical and biological properties of aquatic ecosystems. The water cycle is key to the ecosystem service of climate regulation as well as being an essential supporting service that impacts the function of all ecosystems. Consider the widespread impacts on diverse natural and human systems when major droughts or floods occur. Consequently, human disruptions of the natural water cycle have many undesirable effects and challenge sustainable development. There are two major concerns: First, the need to balance rising human demand with the need to make our water use sustainable by reversing ecosystem damage from excess removal and pollution of water. Traditionally, considerable emphasis has been on finding and accessing more supply, but the negative environmental impacts of this approach are now appreciated, and improving the efficiency of water use is now a major goal. Second, there is a need for a safe water supply in many parts of the world, which depends on reducing water pollution and improving water treatment facilities. The Nitrogen Cycle The vast majority of nitrogen on Earth is held firmly in rocks and plays a minor role in the nitrogen cycle. The second largest pool of nitrogen is in the atmosphere. Most atmospheric nitrogen is in the form of N2 gas, and most organisms are unable to access it. This is significant because nitrogen is an essential component of all cells—for instance, in protein, RNA, and DNA —and nitrogen availability frequently limits the productivity of crops and natural vegetation. Atmospheric nitrogen is made available to plants naturally in two ways. Definition biological nitrogen fixation Where microbes convert N2 gas in the atmosphere into ammonium that can be absorbed by plants. 1. Certain microbes are capable of biological nitrogen fixation, whereby N2 is converted into ammonium, a form of nitrogen that plants can access. Many of these microbes have formed symbiotic relationships with plants—they live within the plant tissue and use

carbon supplied by the plant as an energy source, and in return they share ammonia produced by nitrogen fixation. Well-known examples of plants that do this are legumes (e.g., peas and beans). Some microbes that live in the soil are also capable of nitrogen fixation, but many are found in a zone very close to roots, where significant carbon sources are released from the plant. Natural biological nitrogen fixing processes on land amount to approximately 58 MtN/yr (megatonnes or 58,000,000 tonnes of nitrogen per year) while natural biological nitrogen fixing at sea amounts to approximately 140 MtN/yr for a combined annual flux out of the atmosphere of nearly 200 MtN (Fowler et al., 2013). 2. Lightning causes nitrogen and oxygen in the atmosphere to react and produce nitrous oxides that fall or are washed out of the atmosphere by rain and into the soil, but the flux is much smaller (5-10 MtN per year at most) than biological nitrogen fixation. Biological nitrogen fixation and lightning-induced nitrogen fixation are both natural processes-- i.e., pre-agricultural, pre-industrial that have taken place before humans existed. But nitrogen fixation by human processes (i.e., anthropogenic nitrogen fixation) is now at 210 MtN/yr which has surpassed natural fixation rates. Humans have more than doubled the rate of nitrogen fixation in three ways. 1. Growing legume crops that fix nitrogen biologically (60MtN/yr). Legumes that are grown as agricultural crops (e.g., beans, alfalfa) help fix nitrogen into the soil at a rate of about 60 MtN/yr (Fowler et al., 2013). 2. The industrial production of nitrogen fertilizer which uses energy and pressure to convert nitrogen from the air into ammonia (120MtN/yr) (Fowler et al., 2013). Nitrogen fertilizers are added to enhance the growth of many crops and agricultural plantations. Between 1909-1920, the Haber-Bosch was developed by German chemists that allowed nitrogen to be converted from the air into ammonia. The enhanced use of fertilizers in agriculture was a key feature of the green revolution that boosted global crop yields in the 1970s. The industrial production of nitrogen-rich fertilizers increased significantly during the 20th century and currently amounts to about 120 MtN each year (Fowler et al., 2013). This one anthropogenic source alone now exceeds the total biological nitrogen fixation on land from agricultural crops (60 MtN/yr) and natural plants (58 MtN/yr) combined (Fowler et al., 2013). 3. Another anthropogenic source of nitrogen fixation comes from the burning of fossil fuels (approximately 30 MtN/yr) (Fowler et al., 2013). When fossil fuels are burned (e.g., in power plants, internal combusion engines, oil refineries, etc.) the high temperatures and pressure converts nitrogen (N2) already in the atmosphere into nitric oxide (NO) and nitrogen dioxide (N02) which become deposited to the soil through acid rain or dry deposition. There is also some nitrogen contained in the fossil fuels that becomes oxidized and deposited.

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While the inputs of (new) nitrogen from the atmosphere to the biosphere are substantial, the majority of nitrogen used by plants for growth each year comes from the recycling of nitrogen from the decomposition of dead organic matter. Ammonification (or mineralization) is the release of ammonia by decomposers (bacteria and fungi) when they break down the complex nitrogen compounds in organic material. Plants are able to absorb (assimilate) this ammonia, as well as nitrates, which are made available by bacterial nitrification. The cycle of nitrogen incorporation in growing plant tissues and nitrogen release by bacteria from decomposing plant tissues is efficient and the dominant feature of the nitrogen cycle. Approximately 240 MtN/yr of nitrogen is processed on land and 230 MtN/yr in the oceans (Fowler et al., 2013). Nitrogen can be lost from the system in three main ways. First, denitrifying bacteria convert nitrates to nitrous oxide or N2 gases that are released back to the atmosphere. Denitrification occurs when the bacteria grow under oxygen-depleted conditions, and is therefore favoured by wet and waterlogged soils. Denitrification rates almost match biological nitrogen fixation rates, with wetlands making the greatest contribution. Second, nitrates are washed out of soil in drainage water (leaching) and into rivers and the ocean. Third, nitrogen is also cycled back into the atmosphere when organic material burns. assimilation Acquisition and incorporation of nutrients or resources by plants, e.g. nitrogen or carbon. nitrification Conversion of ammonia into nitrates by microbes. leaching Loss of nitrates from soil in drainage water

Human Interactions With The Nitrogen Cycle Humans are primarily dependent on the nitrogen cycle as a supporting ecosystem service for crop and forest productivity. As described above, most ecosystems naturally retain and recycle almost all of their nitrogen. The relatively little nitrogen that is being gained or lost by fluxes to the atmosphere and water cycle is also nearly being balanced. When humans make large additions of nitrogen to ecosystems leakage often results, with negative environmental consequences. When the amount of nitrate in the soil exceeds plant uptake, the excess nitrate is either leached in drainage water to streams, rivers, and the ocean or denitrified by bacteria and lost to the atmosphere. Definition Eutrophication Accelerated plant growth and decay caused by nitrogen pollution. One of the main gases produced by denitrifying bacteria (nitrous oxide) is an important greenhouse gas that is contributing to human-induced global warming. Other gases released to the atmosphere by denitrifying bacteria, as well as ammonia released from livestock and sewage sludge, are later deposited from the atmosphere onto ecosystems. The additional nitrogen from this deposition, along with the nitrogen leaching into waterways, causes eutrophication. Eutrophication occurs when plant growth and then decay is accelerated by an unusually high supply of nitrogen, and it has knock-on effects, including the following: certain plant species out-competing other species, leading to biodiversity loss and altered ecosystem function; algal blooms that block light and therefore kill aquatic plants in rivers, lakes, and seas; exhaustion of oxygen supplies in water caused by rapid microbial decomposition at the end of algal blooms, which kills many aquatic organisms. Excess nitrates in water supplies have also been linked to human health problems. Efforts to reduce nitrogen pollution focus on increasing the efficiency of synthetic fertilizer use, altering feeding of animals to reduce nitrogen content in their excreta, and better processing of livestock waste and sewage sludge to reduce ammonia release. At the same time, increasing demand for food production from a growing global

population with a greater appetite for meat is driving greater total fertilizer use, so there is no guarantee that better practices will lead to a reduction in the overall amount of nitrogen pollution. What is Biodiversity? You're probably familiar with the word, biodiversity, whether or not you can give an exact definition of it. It's common on the signs at zoos, parks, and nature centers, and it's often used without explanation or definition. Most people understand biodiversity in general terms as the number and mix of plant and animal species that occurs in a given place. Scientists are more precise and include more in their definition. The International Union for the Conservation of Nature (IUCN), which coordinates efforts to catalogue and preserve biodiversity worldwide, defines biodiversity as "the variability among living organisms from all sources including terrestrial, marine and other aquatic ecosystems, and the ecological complexes of which they are part; this includes diversity within species, between species, and of ecosystems" (IUCN, 2018). Rather than just species, biodiversity therefore includes variation from the level of genes and genomes to that of ecosystems to biomes. Even within a single ecosystem, the numbers of species can be impressive. For example, there is a large region of dry forest and savanna in Brazil known as the Cerrado (see Figure 1). This ecosystem alone hosts over 10,000 species of plants, almost 200 species of mammals, over 600 species of birds, and about 800 species of fish. Definition biodiversity The number of different species within an ecosystem (or globally). Biodiversity is also considered a metric of ecosystem health. Generally, biodiversity is greatest in tropical areas—especially "rainforests"—but there are terrestrial biodiversity "hotspots" on all the major continents. Figure 2 is a map of biodiversity hotspots that have been identified by Conservation International: Why is Biodiversity Important? As we learn more about biodiversity, it is becoming clear that there is often a positive association between biodiversity and the integrity of biological systems. This is not to say more diverse systems are "better;" rather, this means that ecological communities with greater diversity tend to be more resilient and robust in the face of environmental stresses (e.g., pollution, climate change, etc.). The products and processes associated with biological systems, which are often called ecological services, are of immense value to the well being of people. An incomplete list of these services and products includes: ● the formation of soil and cycling of nutrients; ● provisioning of food, fresh water, fuel, fiber, and recreation opportunities;

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● the regulation of climate, flooding, and disease; and ● cultural significance (e.g., tied to spiritual/religious ceremonies or beliefs). Definition ecological services Ecosystem functions that are essential to sustaining human health and well-being. Examples include provisioning services such as food, fiber and water; regulating services such as climate, flood, and disease control; cultural services such as spiritual and recreational benefits, and supporting services such as nutrient cycling. Also called ecosystem services. The value of these services is often overlooked or simply taken for granted, but one global estimate puts it somewhere between USD $125-142 trillion per year in 2007 (Costanza et al., 2014). From global food security, to a source of medicines, to even the oxygen in our air, we are dependent on biodiversity and the sustained integrity of ecological systems. Nature is also the basis for a significant part of aesthetic and spiritual values held by many cultures. Given this dependence, it is astounding that many are unaware or—even worse—apathetic about what is occurring and what will likely happen in the near future to our biological resources. We do not contend that any loss of species will affect productivity or function at the ecosystem level. The function of one species can be redundant with others and its loss may not lead to a significant change at the ecosystem level. Whereas redundancy can contribute to the resiliency of natural systems, that should not be a source of comfort. Much ecological theory posits thresholds of species loss beyond which the integrity of ecosystems is threatened; unexpected and possibly permanent new "states" may result. Once a community or ecosystem reaches an alternative state, there may be little that can be done to restore or remediate the system. Therefore, even under optimistic scenarios for rates of species loss (from the local to global

scale) we are facing an uncertain environment. The significance of biodiversity and associated ecological services to current and future generations raises deep questions about whether it is ethical for humans to let their activities lead to the extinction of entire species or ecosystems. Already, laws have been passed in some countries that grant basic legal personhood rights to the Hominidae family of great apes (chimpanzees, bonobos, gorillas, and orangutans). Current Trends: Species Loss and Decline One way scientists gauge trends in biodiversity is by monitoring the fate of individual species of animals and plants. For more than 50 years, the IUCN has compiled information in the "Red List of Threatened Species," which catalogues and identifies species of plants, fungi and animals around the world according to levels of risk of extinction: vulnerable (high risk); endangered (higher risk); and critically endangered (highest risk). Only a small number of plants, fungi and animals that exist on the planet have been assessed so far (approximately 77,300). Each year the Red List is updated with the names of species not previously identified on the list and any changes in threat levels for species on the list. The most recent report concluded that the "results are disturbing with several species groups facing a severe threat of extinction" (IUCN, 2018, p. 3). Figure 4 shows that survival rates of corals, amphibians birds and mammals are also getting worse (i.e., becoming more threatened). Table 1 lists the numbers and proportions of species assessed as threatened on the 2017 IUCN Red List by major taxonomic group. You do not need to memorize this table, but you should be able to contrast major differences between the major taxonomic groups (vertebrates, invertebrates, plants, fungi & protists) in terms of which we know the most about and which are most threatened.

Vertebrates Scientists know much more about the state of vertebrates—especially mammals, birds, and amphibians—than they do about other forms of animal life. Every one of the 5,488 species of mammals that have been described, for example, has been evaluated for purposes of the Red List. Of them, 76 species have become extinct since 1500, and two, Pere David's deer, which is native to China, and the scimitar oryx from Africa survive only in managed facilities. Another 29 of the mammal species listed as critically endangered are also tagged as "possibly extinct;" they are very likely gone, but the sort of exhaustive surveys required to confirm that fact have not been conducted. Overall, approximately 22% of mammal species worldwide are known to be threatened or extinct.

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The Red List categorizes a smaller proportion of the world's 9,990 described bird species—14% —as threatened or extinct. But the raw number of species lost since 1500 is at least 134, and four more species persist only in zoos. Another 15 species of birds are considered possibly extinct. The fact that 86% of bird species are categorized as "not threatened" is good news in the context of the Red List. Among the well-studied vertebrates, amphibians are faring especially poorly. Of the more than 6,000 known species of amphibians, 38 have become extinct worldwide since 1500, and another one, the Wyoming toad, survives only in captivity. Another 120 species are considered possibly extinct. Overall, 2,030, or one-third of the world's amphibian species are known to be threatened or extinct. More troubling still, many amphibian species—42.5%—are reported to be declining, and that number is probably low, since trend information is unavailable for 30.4% of species. Figure 5. Passenger Pigeons. North American passenger pigeons lived in enormous flocks and were once the most numerous birds on earth. Market hunting on a massive scale and habitat destruction combined to extinguish them as a species in the early 20th century. Figure 6. Monteverde Golden Toad. The golden toad of Monteverde, Costa Rica, is one of 11 species of amphibians to become extinct since 1980, due to habitat loss and chytrid fungus. Only small proportions of the world's species of reptiles and fish have been evaluated for purposes of the Red List. Among those, the numbers of species that fall into the threatened category are very high: 1,275 of the 3,481 evaluated species, or 37%, for fish; and 423 of 1,385 evaluated species, or 31%, for reptiles. It should be noted, however, that these percentages are likely overestimates, since species of concern are more likely to be selected for evaluation than others. The World Wide Fund for Nature (WWF) monitors global biodiversity using a "Living Planet Index" (LPI). The LPI is based on monitoring 14,152 populations of 2,706 vertebrate species. Figure 7 shows that the LPI has declined by 58% between 1970-2012. You can read more about the Living Planet Index in this week's readings. The category "invertebrates" lumps together the vast majority of multi-cellular animals, an estimated 97% of all species. It includes everything from insects and arachnids, to mollusks,

crustaceans, corals, and more. Few of these groups have been assessed in a comprehensive way, and so as with fish and reptiles, the Red List percentages of threatened species are skewed high. But assessments within some groups call attention to disturbing, large-scale trends. For example, 27% of the world's reef-building corals are already considered threatened, and many more of them are experiencing rates of decline that move them toward threatened status. The demise of reef-building corals has magnified ecological impacts, since so much other marine life depends on them. It should be understood that information about familiar creatures such as amphibians, mammals, and birds is just a beginning, and that even with the inclusion of some invertebrates the Red List does not provide a comprehensive picture of life on Earth. Scientists have described fewer than 2 million of the 8-9 million species of organisms thought to exist, most of which are insects. And of those 2 million, the status of only 44,838 has been assessed by IUCN. In addition, it should be understood that among the species that have been assessed so far, there is a strong bias toward terrestrial vertebrates and plants, especially the ones that occur where biologists have visited frequently. Red List assessments also tend to focus on species that are likely to be threatened, since the effort also has the aim of enabling people to conserve species. Whereas extinction is the global loss of a species, the elimination of species at a local level— known as extirpation—also poses threats to the integrity and sustainability of ecosystems. Widespread extirpation obviously leads to threatened or endangered status, but absence of species, even at a local scale, can affect ecosystem function. For example, by the mid-1920s wolves had been extirpated from Yellowstone National Park, although they continued to thrive elsewhere. When wolves were reintroduced to the park in the mid-1990s, numbers of elk (a main prey item) decreased significantly. This, in turn, reduced browsing pressure and had a significant effect on the vegetation and plant communities. What mattered for ecosystem function in Yellowstone was whether wolves were present there, not just whether the species survived somewhere. ecosystem function Processes such as decomposition, production, nutrient cycling, and fluxes of nutrients and energy that allow an ecosystem to maintain its integrity as a habitat. extirpation Local extinction of a species; elimination or removal of a species from the area of observation. Causes of Biodiversity Loss The human activities that account for extinction and extirpation vary considerably from one species to another, but they fall into a few broad categories: ● habitat destruction and fragmentation; ● intentional and unintentional movement of species that become invasive (including disease-causing organisms); ● over-exploitation (unsustainable hunting, logging, etc.); ● habitat/ecosystem degradation (e.g., pollution, climate change).

Current Trends: Ecosystem Loss and Alteration Another way of gauging biodiversity involves assessment on the scale of ecosystems. The causes of wholesale losses of ecosystems are much the same as those driving extinction or endangerment of species, with habitat loss and fragmentation being the primary agent. Worldwide, for example, the conversion of land to agriculture and cultivation have led to significant losses in grassland ecosystems. Current estimates indicate that agricultural activity and cultivation systems now cover nearly 25% of the Earth's surface.

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Tropical rainforests, which are the habitats for nearly half of the world's plant and animal species, covered about 4 billion acres in past centuries, but only 2.5 billion acres remain and nearly 1% is being lost annually. Losses have been especially severe in the "paleo" or old world tropics that include Africa and Southeast Asia. The category "wetlands" includes many types of ecosystems, but current estimates indicate that about 50% of the world's wetland habitat has been lost. The former extent of wetland habitats worldwide (fresh, brackish and salt) is difficult to determine but certainly exceeded a billion acres. Case study: The Bison Habitat destruction and fragmentation is the main driver of biodiversity loss. Although when many people think of biodiversity loss the imagery of animal poaching comes to mind (e.g., of critically endangered rhinos). Figure 10 shows piles of bison bones from the 1890s demonstrating the extent of hunting of these animals. Before European colonization, the population of the plains bison numbered in the tens of millions. By the end of the 19th century their population had dropped to only a few hundred. Bison were fundamentally important to the economy and culture of many Indigenous nations living in the interior plains of what is now known as North America. Several factors led to the near extinction of the bison: ● Industrial-scale hunting by settlers for bison hides and meat ● Loss of habitat as settlers took over land for farming and cattle ranching ● Deliberate military policy by settler governments to undermine the food source and economy of Indigenous people as a way to undermine Indigenous resistance to colonialism ● Efforts by railway companies to kill herds that threatened the functioning of railways ● Increased indigenous hunting pressure as a source of income Commercial hunting was the major cause of the rapid population decline of the bison made possible by the expansion of the railway and violent expansion of the American and British (now Canadian) colonial states onto Indigenous lands. Although the population of the bison has been recovered to 500,000, most of these live on commercial ranches. Recovery of the bison population has been frustrated by the loss of their habitat (i.e., ecosystem loss and alteration). In North America, nearly 70% of the tallgrass prairie ecosystem (which once covered 142 million acres) has been converted to agriculture, and losses from other causes, such as urban development, have brought the total to about 90%. Bison bones piled alongside railway. There were so many bison bones that they were ground down into fertilizer and sold by the tonne. The Anthropocene Historical Perspective To understand why biologists talk about ongoing losses of species and ecosystems as the "biodiversity crisis," it is useful to put current and projected rates of species loss into historical perspective. Over the history of life on Earth—a span of 3.5 billion years—nearly all species that existed eventually became extinct. This, of course, is coupled with the processes of speciation

and biological diversification. Rates of extinction and diversification have fluctuated significantly over geologic time. Paleontologists have detected five episodes of mass extinction over the last 540 million years (also see Figure 1). These periods contrast with the relatively constant "background rate" of extinction observed over the geologic record, and include the relatively well-known event 65 million years ago when most of the extant dinosaurs went extinct. By definition, these episodes are characterized by the comparatively rapid loss of at least three- fourths of the species thought to exist at the onset of the event. Recently, the question has been posed whether present-day rates of species loss constitute a sixth episode of mass extinction (Barnosky et al., 2011). Even with caveats about uncertainty in how many species there are today (only a fraction of the estimated total have been described, especially for plants, invertebrates, and microbes) and about comparisons of the fossil record with modern data, it appears that estimated rates of loss in the near future could rival those of past mass extinctions. Some estimates indicate that we will see a 30% loss of species within decades. Put another way, forecasted rates of species loss could be as much as 1000 to 10,000 times higher than background rates. Timeline showing five mass extinctions and the Anthropocene epoch within the Quarternary Period (one of the three periods of time within the Cenozoic Era)

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The current rapid loss of biodiversity we are experiencing in an extremely short period of geological time is one characteristic of what is being called the Anthropocene. Recognizing the Anthropocene as a formal epoch in geological time draws attention to the ways that humans have significantly transformed the Earth's ecosystems, atmosphere and even its geology. Scholars have suggested several possible dates for marking the start of the Anthropocene: the Great Acceleration of the mid-20th century; the start of the industrial revolution; transatlantic colonization; the development of vast empires and dynasties around the world several thousand years ago; or even further back 12,000 years ago to the agricultural revolution. Discovering Anthropocene 1,000-10,000 Years From Now One way to think of the Anthropocene is to consider what geologists, paleoarchaeologists, paleobotanists and paleoclimatologists working 1,000 or 10,000 years in the future would discover in the layers of sediments and fossils that correspond to today's human activities. Here is what they might find: ● A sharp decrease in biodiversity ● The buried ruins of mega-cities (steel, concrete, etc.) ● A distinct layer of radioactive soil and pockets of nuclear waste associated with nuclear arms testing and nuclear energy ● A distinct layer of heavy plastics, glass, metals, styrofoam, and chemicals that do not decompose ● Evidence of rapid climate change: increases in atmosphere CO2 levels, melting of ice at the Earth's poles and of glaciers, coastal flooding and erosion, human migration, etc. ● Evidence of major deforestation and landscape change associated with agricultural practices and urban sprawl ● Changes in geomorphology associated with human-made drainage systems, canals, quarries, etc. ● Loss of sediments in river deltas associated with megadams upstream that are blocking sediments from reaching the ocean. ● A layer of chicken fossils around the globe: more than 60 billion chickens are consumed per year(!) whose bones end up in landfills and will eventually become fossilized ● A layer of mercury associated with coal power plants The concept of the anthropocene is helpful politically for helping humans to realize the incredible scope and historical significance of our production, consumption, and waste generating activities. ANTHROPOCENE: The Human Epoch Trailer is a trailer for a good film on the anthropocene that had its world premier at the Toronto International Film Festival in 2018: Here is how the film is described by the producers: A cinematic meditation on humanity’s massive reengineering of the planet, ANTHROPOCENE: The Human Epoch is a four years in the making feature documentary film from the multiple- award winning team of Jennifer Baichwal, Nicholas de Pencier and Edward Burtynsky.

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Third in a trilogy that includes Manufactured Landscapes (2006) and Watermark (2013), the film follows the research of an international body of scientists, the Anthropocene Working Group who, after nearly 10 years of research, are arguing that the Holocene Epoch gave way to the Anthropocene Epoch in the mid-twentieth century, because of profound and lasting human changes to the Earth. From concrete seawalls in China that now cover 60% of the mainland coast, to the biggest terrestrial machines ever built in Germany, to psychedelic potash mines in Russia’s Ural Mountains, to metal festivals in the closed city of Norilsk, to the devastated Great Barrier Reef in Australia and surreal lithium evaporation ponds in the Atacama desert, the filmmakers have traversed the globe using high end production values and state of the art camera techniques to document evidence and experience of human planetary domination. At the intersection of art and science, ANTHROPOCENE: The Human Epoch witnesses in an experiential and non-didactic sense a critical moment in geological history — bringing a provocative and unforgettable experience of our species’ breadth and impact (Mercury Films, 2018) Explaining Socio-Ecological Crisis Human Impact on the Environment: The I=PAT Equation What are the main factors causing the socio-ecological crisis? As we discussed in the first module, sustainability is a multi-dimensional historical, political-economic, socio-cultural and technological problem. This means that we cannot simply point to only a few factors that are causing the problem. Sustainability problems are linked to the maldistribution of resources and a system of values related to historical processes of colonialism and neo-colonialism, capitalism, patriarchy, racism and authoritarianism. Explaining these processes is the work of social scientists, philosophers, historians and artists. Some scientists have tried to model deteriorating environmental conditions using a simple mathematical formula: I=PAT Human impacts on the environment (I) = Population (P) x Affluence (A) x Technological capacity (T) The I=PAT equation basically states that greater negative environmental impacts are to be expected as human populations and consumption levels increase. But this depends on the level of technological efficiency or productivity which can decrease or increase that negative impact. In this equation, I represents the impacts of a given course of action on the environment, P is the relevant human population for the problem at hand, A is the level of consumption per person, and T is impact per unit of consumption. The equation is not meant to be mathematically rigorous; rather it provides a way of organizing information for a “first-order” or

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high-scale analysis (Brawn, Ward, & Kent, 2012). Before discussing some of the limitations and criticism of the I=PAT equation, let's look at how it helps us to understand some of the major factors that influence socio-ecological change. Impact (I) Environmental impact is the dependent variable in this equation. All human activities have some environmental impacts (most negative, some positive). The I=PAT equation generally assumes that increasing consumption will have a negative environmental impact (air and water pollution, land degradation, biodiversity loss, climate change, depletion of resources, etc.). In the next two sections we will discuss some ways of measuring environmental impacts such as using the concept of ecological footprint. Population (P) Population is expressed in terms of total human numbers for the population under study. People must consume resources and produce some level of pollution in order to survive. It is therefore assumed that as the population increases, the environmental impact will increase (assuming all else stays the same in terms of lifestyles and technological efficiencies). The idea that population growth is at the heart of environmental problems has a long and fraught history. This theory was popularized by Thomas Malthus, an English cleric and scholar in who wrote a now famous book in 1798 called An Essay on the Principle of Population. In it, Malthus deduced that population grew at a geometric (or exponential) rate while food production only grew at a smaller linear or arithmetic rate. This led Malthus to argue that the growing population would always face problems such as famine and disease. Scholars in the 1960s took up Malthus' ideas to argue that the world's population was out-pacing the planet's capacity to absorb pollution and to provide resources, leading to the notion of "overpopulation." Neo- Malthusian ideas in many ways influenced the development of the I=PAT equation, which bring focus to population growth as a major cause of environmental deterioration. One problem with Malthus' predictions of unavoidable famine associated with population growth is that he did not foresee the development of new agricultural practices and technologies which allowed food production to increase geometrically (e.g., the set of agricultural research and development initiatives between 1930-1960 known as the Green Revolution). At the same time, Malthus did not foresee the use of family planning and contraceptives which has slowed population growth. Similarly, neo-Malthusians in the 1960's and 1970's who warned of societal collapse due to population growth and resource depletion failed to fully account for technological developments that allowed for more efficient use of existing resources, substitutions and the discovery of new sources of non-renewable resources.

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Figure 1. This graph estimates what the probable population of the world will be through to the end of this century. By 2050, the United Nations estimates that the world's population will be at 9.77 billion people. By 2100, the world's population is estimated to be 11 billion people Both Malthus and neo-Malthusians have been criticized for harbouring biases against the poor as the cause of social and environmental problems rather than systems of resource (mal)distribution set up to favour the wealthy elite. Although we can say that problems such as climate change are exacerbated by population growth, it is important to recognize that people in wealthy countries produce far more greenhouse gases per person on average than people in low-income countries. So when assessing the driving cause of climate change and other environmental problems it is critical to not simply consider population growth but also to examine systems of distribution and control over resources and the relative abilities of people to generate pollution. This brings us to the variable, affluence. Affluence (A) We must all consume a basic amount of food and materials to survive. But consumption usually has a negative environmental impact: clearing land for agriculture production eliminates biologically diverse habitats; electronics require the extraction of rare minerals and plastic; electricity, long distance travel and the circulation of goods require fossil fuels; and so forth. Since those with more of the world's wealth are able to consume at much higher rates, they tend to have a greater overall negative environmental impact. The amount of land and resources that a person consumes in a year, including the amount of land required to absorb the pollution they create, is referred to as one's ecological footprint measured in units of global

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hectares per person (or "per capita"). We will discuss how global hectares are measured and calculate your own personal ecological footprint in a later section in this module. Another common measure used to approximate affluence at a national and global scale is gross domestic product (GDP) per capita. GDP measures the value of goods and services produced in an economy for a given year so this gives a good indication about the level of consumption. One problem with using GDP per capita in the I=PAT equation is that GDP includes consumption that is good for the environment such as environmental remediation. But overall, GDP does provide us with a general indication about society's overall level of consumption which for the most part has negative environmental impacts. There is far less "positive consumption" than "negative consumption" in terms of environmental impact. Even so-called "green products" have negative environmental impacts – just less than the non-green version. Electric cars only contribute about 10%-24% less to global warming than conventional cars over the lifetime of the vehicle (Hawkins et al., 2013). Electric vehicles do not have "zero emissions" despite being advertised this way. Both conventional and electric vehicles have a large negative environmental impact in terms of the resources and energy used in their manufacturing known as "embedded carbon" or "embedded emissions." Whether a vehicle emits greenhouse gas emissions from the tailpipe is only one consideration, and some have argued that manufacturing a car may generate as much greenhouse gas emissions as driving it (Berners-Lee & Clark, 2010). Assessing the overall environmental impact of cars must examine the amount of emissions from the extraction of minerals to make metal for the car; the electricity needed by factories for manufacturing and assembly of vehicles; the oil used for plastic components; the emissions from transporting vehicle parts and finished vehicles around the planet; the rubber used for tires; the land and materials required to construct and maintain road networks; the energy required to dispose of the vehicle; and so forth. Carrying out this type of overall assessment of a product's environmental impact from "cradle to grave" is referred to as a life-cycle assessment. Pause for a moment to consider what you think you do in your everyday life that causes the most significant negative environmental impact on the planet? Figure 2 identifies the most high-impact personal lifestyle choices that people living in developed countries can make who want to reduce their personal contribution to climate change. In accordance with the I=PAT equation's focus on population growth, the infographic lists having one fewer child as the most significant way to reduce your household's contribution to climate change. Reflecting the climate impact of affluence and consumption, the infographic also shows that living without a car, not taking long-distance flights and eating a plant-based diet are also significant actions for reducing your personal contribution to climate change.

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Figure 2. Personal choices to reduce your contribution to climate change. This infographic is based on 39 peer-reviewed journal articles, carbon ecological footprint calculators and government sources You can complete this for yourself and for your parents/guardians. You might also look up the income and wealth of well-known CEOs, politicians, and other members of the public to get a sense of where they stand financially relative to the rest of the world. For the last census, the median total income amongst Canadians was $34,204 (although higher for men at $40,782 than women at $28,860) Relationship Between Affluence and Environmental Degradation is not Simple Although the I=PAT equation reflects the negative impact that affluence has on the environment, there are several factors complicating any simple relationship between affluence and environmental degradation: In some cases, extreme poverty and/or lack of long-term rights to an area of land or fishery leads people to degrade their environment. The poor may consume little but in a way that directly degrades local environments (e.g., agriculture practices on sensitive land; over- harvesting bushmeat; cutting down rainforest to plant food gardens; engaging in illegal logging, mining or other resource extraction activities). But these activities are a result of being marginalized due to processes that are driven by elites who control greater amounts of resources either directly (e.g., through ownership of land) or indirectly (as policy-makers, through having greater global purchasing power, or through their ownership of stocks and international investments, etc.).

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Example: Socioecological Degradation in Haiti For example, extreme poverty in Haiti has forced people to burn wood charcoal for energy production. This has led to very high levels of deforestation and soil erosion. Haiti's poverty and deforestation must be understood not only in terms of the relatively impoverished individuals currently cutting down trees to make charcoal, but also within an historical context. Persistent poverty and unequal distribution of land and wealth in the country is the result of many factors: slavery; colonialism; indebtedness to France following independence for the "loss" of enslaved populations; foreign meddling and occupations; as well as rule by authoritarian regimes. So rather than say that the poor cause environmental degradation, it is more accurate to say that the process of impoverishment (and enrichment of others) causes socio-ecological degradation. Some affluent people put their money towards a "green lifestyle" Example: Environmental Impact of Affluence For example: eating more expensive organic food; buying energy efficient homes and appliances; driving more expensive electric vehicles; even donating to environmental and humanitarian organizations. These environmental decisions must be weighed against negative environmental impacts of affluence, for example: greater air travel, larger overall houses, multiple cars, more overall retail purchases, greater meat consumption (especially beef, which generates more greenhouse gases), etc. When considering affluence, it is not only important to look at the direct environment impacts of lifestyle choice, but to also consider how those with higher incomes are able to more effectively influence the political system (for better or worse in terms of sustainability) through donations to political parties, candidates and campaigns, or by having the resources to run for political office. We should reflect on what the environmental impacts would be on evenly distributing the world's wealth? Is a more equal world necessarily a more sustainable one? An answer for this question is empirical as much as it is political. We would need to assess how production, circulation and consumption patterns would shift under more egalitarian conditions. Although luxury items tend to have high environmental impacts (e.g., private jets and yachts; jewelry; pets; etc.) that would likely be replaced with lower-impact consumption under more egalitarian conditions, other luxury items potentially have a lower environmental impact (e.g., commissioned paintings or music; massages and pedicures; etc. ). There are of course many other social reasons for distributing wealth more equally besides direct environmental considerations. Technological Capacity Technology in the I=PAT equation refers to human inventions as well as systems more broadly. Technological capacity measures the amount of environmental impact per unit of consumption. It accounts for the efficiency of a given technology in terms of producing, transporting and disposing of goods and services. We will discuss technology in more detail in Module 3. Technology that reduces the negative environmental impact per unit of consumption is said to "decouple" consumption from impact.

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Using the I=PAT equation Suppose we wish to know how much we need to improve our technological decoupling by 2050 in order to simply maintain global environmental quality at present day levels. For this we need to have some projection of human population (P) and an idea of rates of growth in consumption (A) (Brawn, Ward, & Kent, 2012). We know from Figure 1 that the world's population will grow from 7.6 billion in 2018 to 9.7 billion in 2050 (an increase of 28%). Figure 3 shows worldwide GDP between 1961-2017 having an average annual GDP increase of 3.5%. An annual growth of 3.5%, when compounded for 32 years, means that the global economy will be three times as large at mid-century as today. This ratio of technological capacity, T 2050 :T 2018 , can be rounded from 1:3.8 to 1:4. This means that just to maintain current environmental quality over the next thirty-two years in the face of growing population and levels of affluence, our technological decoupling will need to reduce impacts per unit of consumption by about a factor of 4.

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The I=PAT Equation in Practice The I=PAT equation suggests a simple direct relationship between the variables. For example, it suggests that as technological efficiency improves (i.e., impact per unit of consumption, or the value of T, decreases) then the overall environmental impact will decrease. But in practice, the three variables P, A, and T interact with each other in complex ways that do not always lead to this type of direct relationship. As we will learn in the following module, greater efficiencies can actually lead to increased consumption if efficiencies lower market prices and thereby encourage people to consume more (this is known as the Jevon's Paradox). And as mentioned previously, greater affluence may reduce rather increase environmental impacts in certain ways. To account for these complexities, the I=PAT equation is often understood as I=f(PAT). The "f" refers to "a function of." This means that the exact relationship between the variables and between the variables and environmental impacts need to be ascertained empirically rather than assuming a direct or linear relationship. Measuring Wellbeing Is Growth Good? News headlines and politicians often discuss the economy in terms of whether or not it is growing. "Economic growth" is assumed to be a positive thing and politicians are held to account for whether or not they have grown the economy over the past year. Economic growth is the goal for stock investors and bank lenders who stand to benefit from a positive return on their investments or higher interest rates on loans, respectively. For corporations, a growing economy means they are producing and selling more and more goods and services. Workers often associate economic growth with job creation; if the economy is growing, workers feel more secure that they can keep or find employment. But should economic growth be celebrated as a positive process? GDP growth is in fact a very poor measure of a population's happiness. It says nothing about the quality of jobs people have; the level of equality; how much love they have in their life; or the health of the environment. In terms of employment, economic growth does not directly relate to the creation of jobs or the creation of long-term, well-paying jobs. Because investors and corporations main objective is to generate higher profits, this leads them to constantly invest in labour-saving technologies that increase productivity and profits but actually lower employment within the firm (or maintain employment at the same levels despite a growth in revenues). Think of robots replacing human workers. Economic growth does not automatically reduce socio-economic inequalities and it may actually Increase inequality. People who have money to invest in the economy are generally wealthier to begin with and so will benefit the most from economic growth unless progressive taxes are put in place to more

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equitably redistribute the new wealth being created. Existing tax structures will increase tax revenue for the government to some extent during periods of economic growth which could allow governments to make social investments, build infrastructure or make payments on government debt. But the government could also increase tax revenue by raising taxes on existing economic activity without there necessarily being economic growth. Alternatives to GDP An alternative approach to measuring happiness or well-being called the Canadian Index of Wellbeing (CIW), has been developed right here by researchers at the University of Waterloo. The CIW is based on 8 domains: living standards, healthy population, democratic engagement, community vitality, environment, leisure and culture, time use, and education (see Figure 3). Each of these domains are associated with 8 measurable indicators. Figure 3. The eight domains of the Canadian Index of Wellbeing Watch the following video produced by the University of Waterloo Applied Health Sciences Department, Start the Conversation! An introduction to the Canadian Index of Wellbeing. This video provides an overview and important information about the CIW that is not covered in the text.

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The University of Waterloo researchers tracked Canada's GDP over two decades in relation to changes in the CIW indicators for each domain. Their findings are shown below (Figure 3). Notice that while GDP rose by 28.9% between 1994-2010, the CIW only grew by 5.7%. The domains that improved during this time period are shown in green while those that degraded during this time period are shown in red. Figure 3. Canadian Index of Wellbeing compared to GDP, 1994-2010

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