All ESS flashcards

Question

What are the implications of the first law of thermodynamics?

Answer 1

In an open system (such as an ecosystem), energy will never increase, so it has to be constantly inputted. Humans cannot create energy, so we have to use and transform what is more convenient.

Answer 2

- Light energy is crucial for photosynthesis in an ecosystem. - Energy becomes less concentrated and efficient as it changes form into chemical energy. - Some energy is lost as heat during the transformation process. - This loss and de-concentration of energy describe the process of entropy. - As energy transforms or transfers, entropy increases, leading to energy loss. - Without additional energy input into the system, the members of that ecosystem would not be able to survive.

Answer 3

As energy transforms or transfers, entropy increases and energy is lost.

Answer 4

Entropy will always increase, so in order to survive, organisms must be supplied with more energy.

Answer 5

Stability is the ability of an ecosystem to remain balanced (at equilibrium).

Answer 6

Climate. Biodiversity. Trophic complexity. Nutrient stores. Frequency/intensity of disturbances.

Answer 7

An ecosystem with a steady climate is more stable than ones with extreme weather, since their extreme weather is considered a disturbance. The fewer disturbances that occur, the more stable the ecosystem.

Answer 8

Higher biodiversity creates a more complex ecosystem. Complex ecosystems are more stable because if one part fails, another can support it. Simple ecosystems may reach their tipping point if one component collapses and nothing can support it.

Answer 9

Similar to biodiversity, ecosystems with trophic complexity are more stable because they are not as susceptible to collapse if one organism is lost.

Answer 10

The size of nutrient stores, the relative distribution of nutrients in the stores and the rate of nutrient cycling all determine stability. If all the nutrients are held in a single store and that store is lost, then the system can collapse very quickly.

Answer 11

Small, infrequent disturbances can be tolerated and overcome, whilst large and/or frequent ones cause problems.

Answer 12

Equilibrium is the steady state of an ecosystem where all organisms are in balance with their environment and with each other.

Answer 13

Unstable static equilibrium and steady-state equilibrium?

Answer 14

Unstable static equilibrium occurs only in non-living systems. It occurs when the components of the system remain constant over long periods of time.

Answer 15

Steady-state equilibrium occurs in a living system, when there are many changes within boundaries, and negative feedback brings the system back to equilibrium.

Answer 16

Negative feedback promotes stability by reversing the change that has occurred and re-establishing equilibrium.

Answer 17

Positive feedback disrupts stability, and keeps the system away from equilibrium.

Answer 18

If humans have a fever that is too high, they can die. As body temperature increases, humans sweat. The evaporation of the sweat removes heat from the body and humans cool down. | Any other relevant examples are also applicable

Answer 19

Methane is a greenhouse gas that causes temperatures to rise, which melts permafrost. When permafrost melts, methane is released, which is a greenhouse and further causes temperatures to rise. | Any other relevant examples.

Answer 20

A tipping point is a point where positive feedback causes the system to derail, and establish a new equilibrium.

Answer 21

If ecosystems reach their tipping points, environmental services (water cycle, clean air, pollination) could collapse, food production capacity will decrease, marine ecosystems will drop in productivity and the climate may be unsuitable for human existence.

Answer 22

Sustainability is the management of the exploitation of natural resources that allows for replacement of the resources and full recovery of the ecosystems that may be affected by extraction.

Answer 23

Renewable resources are those that can be replaced as fast as they are used.

Answer 24

Non-renewable resources are those that are used quicker than they can be replaced.

Answer 25

The global stock of all natural resources that can be used by humans.

Answer 26

Natural income is the economic yield from natural capital.

Answer 27

If natural capital is managed sustainably, it will continue to provide natural income for future generations. If natural capital is managed unsustainably, it will cause a positive feedback cycle, which will result in the depletion of that capital.

Answer 28

Millennium Ecosystem Assessment (MA)

Answer 29

An EIA (Environmental Impact Assessment) is a study done to identify any environmental impacts of a proposed project and to lessen the environmental impact that the project would create.

Answer 30

1) Scoping 2) Baseline study 3) Predicting effects 4) Mitigation 5) Report produced

Answer 31

Pollution is the introduction of a substance into the natural environment at a rate at which it cannot be broken down.

Answer 32

Point-source pollution is pollution coming from a single, identifiable source. E.g. An oil spill from a ship.

Answer 33

Non-point source pollution is pollution from different sources that make it difficult to monitor and control. E.g. Rubbish in a river dumped at multiple upstream points.

Answer 34

Organic pollutants are those that originate from something that was living at one point. They are carbon-based and can be toxic. E.g. Human sewage.

Answer 35

Inorganic pollutants are those that are non-living and usually do not contain carbon. E.g. Phosphates from fertilizer.

Answer 36

Persistent pollutants are those that do not break down easily. The most dangerous ones are POP’s (Persistent Organic Pollutants). E.g. DDT.

Answer 37

Biodegradable pollutants are those that breakdown/decompose due to microorganism activity. E.g. Food waste.

Answer 38

Acute pollution is pollution that occurs suddenly and in large quantities over a short period of time. E.g. Oil spill from a pipe.

Answer 39

Chronic pollution is the persistent, long-term emission of pollutants in low concentrations. E.g. Run-off from urban areas washes oil from the roads into rivers.

Answer 40

Primary pollutants are those that are released directly from a source into the environment. E.g. Carbon dioxide from car exhausts.

Answer 41

Secondary pollutants are those that are formed when two or more primary pollutants react together. E.g. Ozone.

Answer 42

Health impacts Ecosystem impacts Wildlife impacts Economic impacts

Answer 43

Respiratory problems Pollution can contaminate water and/or food sources, leading to the harmful introduction of substances to humans/animals.

Answer 44

Disruption of ecosystems Deterioration of water quality Contamination of soil

Answer 45

Habitat loss Disruption of food chains Harm animals health/reproduction

Answer 46

Exacerbate healthcare costs Damage industries Result in a loss of workforce productivity

Answer 47

Education Legislation Remediation

Answer 48

Campaigns Advertisements Economic incentives.

Answer 49

Legislation can outlaw the emission of pollutants straight from the source, and control the amount of each pollutant that can be emitted into the atmosphere.

Answer 50

Remediation is the clean-up of existing pollution to restore the damage created. It is the most difficult and expensive method.

Answer 51

DDT is an example of a POP (Primary Organic Pollutant), and it cannot be broken down.

Answer 52

An ecosystem is defined as a community of interdependent organisms and the physical environment they interact with.

Answer 53

Non-living factors of a system.

Answer 54

Living factors of a system

Answer 55

Temperature, sunlight, pH, salinity, etc

Answer 56

Producers, consumers, decomposers, species, populations, etc

Answer 57

Producers are plants that convert energy (sunlight) into matter (food for other trophic levels).

Answer 58

Consumers eat the plants and/or the organisms that consume the plant, depending on what trophic level they are.

Answer 59

Decomposers are usually microorganisms or small organisms (worms, bacteria, etc) that break down waste into component parts for reuse.

Answer 60

Species are groups of organisms with common characteristics that can interbreed to produce fertile offspring, as organisms do not function individually.

Answer 61

Populations are groups of individuals in the same species living in the same area at the same time.

Answer 62

A habitat is the environment in which a species usually lives.

Answer 63

The niche is the role an organism plays and the position it holds in the environment.

Answer 64

Fundamental and realised

Answer 65

A fundamental niche is all the conditions that an animal can survive and reproduce.

Answer 66

A realised niche is the actual habitat a species occupies as a result of limiting factors in its environment.

Answer 67

Density-dependent and density-independent

Answer 68

Limiting factors are the resources in the environment that limit the growth, abundance and distribution of organisms/populations in an ecosystem.

Answer 69

Density-dependent limiting factors are those that only affect the population when it reaches a certain density (competition, disease, parasitism and predation). E.g. Disease spreads best when there are a lot of organisms to infect. They tend to be biotic factors.

Answer 70

Density-independent limiting factors will limit populations regardless of their density (sunlight, temperature, water and natural disasters). They tend to be abiotic factors.

Answer 71

The carrying capacity of an organism is the maximum number of individuals a species can sustainably support in a given area.

Answer 72

J-Curves and S-Curves.

Answer 73

Exponential, crash-and-boom model.

Answer 74

There is a brief period of exponential growth Population growth then slows down once resources become scarce. This then stops once the population reaches the carrying capacity.

Answer 75

Predation occurs when one organism (the predator) hunts and kills another in order to provide it with energy for survival and reproduction.

Answer 76

Herbivory is the consumption of plant material by an animal (herbivores).

Answer 77

Parasitism occurs when an organism (the parasite) takes nutrients from another organism (host).

Answer 78

Mutualism occurs when two organisms of different species exist in a mutually beneficial relationship.

Answer 79

Disease is the departure from the normal state of functioning of any living organism (plant, animal or human).

Answer 80

Competition is when organisms compete for a resource that has limited supply.

Answer 81

Intraspecific and interspecific

Answer 82

Intraspecific competition is when members of the same species compete for a limited resource.

Answer 83

Interspecific competition is when members of different species compete for a limited resource.

Answer 84

A community is a group of populations living and interacting with each other in a common habitat.

Answer 85

The difference between ecosystems and communities is that the ecosystem includes the abiotic components, whereas a community is simply the biotic components.

Answer 86

Photosynthesis is a process in which light energy turns into chemical energy by primary producers

Answer 87

Light, carbon dioxide, water

Answer 88

Glucose and oxygen

Answer 89

6C02 + 6H20 → C6H1206 + 602

Answer 90

Respiration is the reverse process as photosynthesis.

Answer 91

Oxygen and glucose

Answer 92

Carbon dioxide and energy

Answer 93

A trophic level of an organism is the number of steps it is from the start of the start of the food chain. A primary producer is in the first trophic level because they are the start of the food chain, a primary consumer is 2nd, a tertiary consumer is 3rd, etc.

Answer 94

Food chains model trophic levels

Answer 95

Energy efficiency = (Energy output/Energy input) x 100.

Answer 96

Bioaccumulation is the increase in the concentration of a pollutant in an organism's body over time as they ingest it.

Answer 97

Biomagnification is the increase in the concentration of a pollutant as it moves up a food chain, from one organism to another.

Answer 98

The difference between the two is that biomagnification is the increase in pollutants through different organisms, whereas bioaccumulation is the increase in pollutants in one organism.

Answer 99

Ecological pyramids are the final way of showing the feeding relationships between groups of organisms.

Answer 100

Pyramids of numbers, biomass and energy.

Answer 101

A quantitative representation of the number of individual organisms at each trophic level in an ecosystem.

Answer 102

Pyramids that show the amount of biomass at each trophic level.

Answer 103

Biomass is the mass of living organisms in a given area expressed as dry weight of mass per unit area.

Answer 104

Pyramids that show the amount of energy at each trophic level.

Answer 105

Mass per unit of an area (e.g. grams per unit - gm-2)

Answer 106

Joules per square metre per year (Jm2yr-1).

Answer 107

The solar constant is the average amount of solar energy that reaches the atmosphere when the sun is the average distance away from the earth.

Answer 108

Insolation is the amount of solar radiation received by a surface unit over a given time.

Answer 109

The reflectivity of a surface is called the Albedo.

Answer 110

Net primary productivity: NPP= GPP (gross) - R (respiration). Expressed as gm-2y-1

Answer 111

Gross secondary productivity: Total productivity of consumers.

Answer 112

Net secondary productivity: NSP = GSP - R (respiration)

Answer 113

Gross secondary productivity: GSP = Food eaten - faecal loss (g/J m-2y-1)

Answer 114

Sustainable yield is the amount of biomass that can be extracted without reducing the natural capital of an ecosystem. Natural capital are natural resources that can be economically exploited.

Answer 115

Matter cycles (meaning it goes in both directions)

Answer 116

Energy flows (only goes in one direction)

Answer 117

Plants absorb carbon through photosynthesis. Animals eat plants and carbon is transferred into their bodies. Animals also release carbon through respiration. Decomposers (such as the shitake mushroom) break carbon down into organic matter when plants and animals die. Over millions of years, Carbon is packed under intense pressure to create fossils. Fossils are excavated and combusted in order to extract energy.

Answer 118

Photosynthesis: C02 from the atmosphere is absorbed into plants. Sedimentation: Carbon settles after decomposition and forms part of sediments. Combustion: Carbon is released back into the atmosphere (by burning it). Diffusion: CO2 from oceans back into the atmosphere by molecule movement.

Answer 119

Atmospheric Terrestrial plants Marine plants Soil and organic matter Coal, oil and gas Sediments and rocks Ocean surface Deep oceans

Answer 120

The biosphere is the worldwide sum of ecosystems (the area where anything is alive).

Answer 121

1. Nitrogen fixation: Nitrogen gas from the atmosphere is transformed into amonnium (NH4+) 2. Ammonification: Nitrogen from DOM is transformed into amonnium (NH4+). 3. Nitrification: Ammonium is transformed into nitrates (No2-) and then further transformed (No3-). 4. Assimilation: Nitrates are uptaken by plants, and are broken down as ammonium ions (stage 2). 5. Denitification: No3- is tranformed back into nitrogen gas.

Answer 122

Atmospheric storage. Soil organic matter. Ocean. Terrestrial plant biomass.

Answer 123

Less nitrogen enters the atmosphere because soil is cleared for economic exploitation (less denitrification). Nitrogen oxides (pollutants) are released due to greater combustion. This contributes to air pollution and smog. Chemical fertilisers are used (haber-bosch process) instead of organic fertilisers. This removes nitrogen from the atmosphere (less for the nitrogen process). Livestock release nitrogen through waste into the soil and nearby aquatic systems.

Answer 124

Biomes are associations of vegetation that share similar climate characteristics.

Answer 125

Temperate forest Tropical Rainforest Desert Tundra Mangrove Temperate bogs Coral reefs Hydrothermal vents.

Answer 126

K-strategy organisms reproduce small quantities with high quality (a lot of parenting, high survival rates). These organisms survive best in stable environments.

Answer 127

R-strategy organisms reproduce large quantities in a tradeoff for quality (no parenting, at least some of them survive). These organisms survive best in unstable environments.

Answer 128

The graphical representation of population longevity is called a survivorship curve.

Answer 129

K strategy organisms

Answer 130

Type II are middle ground organisms, they are equally likely to die at birth than to die of old age.

Answer 131

Type III are R-selected species, where few survive to an old age.

Answer 132

Succession is the predictable change in a vegetative area over time.

Answer 133

Primary succession occurs in areas that have never had vegetation, whereas secondary succession occurs when human impact has left an area disturbed (eg. abandoned fields, deforested areas, etc).

Answer 134

Ecological resilience is an ecosystem's capacity to sustain its processes following ecological disturbances.

Answer 135

Stability: THow well the ecosystem can withstand disturbances. Precariousness: The precariousness of an ecosystem is how close it is to its breaking point.

Answer 136

Colonisation is the phase in which pioneer species adapt to extreme conditions. These species kick-start the ecosystem. Soil starts to form through weathering and decomposition. Establishment is the phase in which the quantity of natural resources increases and food, water and habitats develop. In this phase, the ecosystem starts to work as a whole and not as individual components. Competition is the phase in which abiotic limiting factors are less extreme, meaning that the environment becomes more stable, and more complex organisms populate the area. The complex organisms outcompete the original species. Stability is the phase in which the amount of new organisms entering the ecosystem decreases. K-strategists dominate the ecosystems. Climax is the phase in which the ecosystem has high levels of biodiversity and is at equilibrium. The ecosystem will remain this way as long as the climatic conditions remain the same.

Answer 137

Zonation is the change in a vegetative community alongside an environmental gradient.

Answer 138

An environmental gradient is the change in environmental conditions over a geographical area (altitude, water depth, proximity to ocean, etc).

Answer 139

Altitudinal zonation is triggered by changes in altitude.

Answer 140

Altitudinal zonation is triggered by changes in latitude.

Answer 141

A small quantity representing the whole, like a soil sample indicating ecosystem contamination.

Answer 142

A plot of any shape used to sample, especially for plants or non-motile organisms.

Answer 143

A series of yes/no questions to help identify organisms.

Answer 144

N = (n1 x n2) / m2 Where: N = Total population. n1 = Number of animals marked in the first capture and release. n2 = Number of animals recaptured. m2 = number of animals

Answer 145

The term "biodiversity" refers to the amount of living diversity per unit area.

Answer 146

Genetic biodiversity. Species biodiversity. Habitat biodiversity.

Answer 147

Species biodiversity is the variety of species per unit area.

Answer 148

Species biodiversity measures both the richness and the abundance of the species in a given area.

Answer 149

Simpson's diversity index

Answer 150

D = Simpson Diversity Index. N = Population of all species in an area. n = population of a particular species.

Answer 151

Habit diversity is a measure of how many habitats are present in an ecosystem, community or biome.

Answer 152

Genetic diversity is the range of genetic material present in a gene pool.

Answer 153

A gene pool is the set of all genes present in a population.

Answer 154

The age of an area. The environmental stability of an area. The range of habitats in an area.

Answer 155

Vertical extent of vegetation: with more canopy levels, there is a higher possibility of biodiversity. Altitude/latitute variation: with a range of altitudes, there is a higher possibility of biodiversity. Variation in rock and soil types: variations in the abiotic environment lead to more biodiversity.

Answer 156

Artificial selection, convergent evolution, embryology, biogeographical distribution and fossil records.

Answer 157

Speciation is the formation of new species through biological processes.

Answer 158

Isolation is when something stops organisms from mating with their usual partners, leading to changes in their genes.

Answer 159

Geographic, temporal and behavioural.

Answer 160

Geographic isolation occurs when populations are physically separated and can no longer interbreed.

Answer 161

Temporal isolation occurs when populations are active at different times of the day and therefore do not meet to breed.

Answer 162

Behavioural isolation occurs when populations have distinct mating rituals.

Answer 163

Natural selection is the gradual evolutionary change that results from genetic variation in each generation.

Answer 164

Within the population of one species, there is genetic diversity (not every organism is the same). This is called variation. Some genetic traits may be stronger than others to deal with environmental challenges and therefore have comparative advantage (advantage when compared to other members of their species). Fitter individuals with comparative advantage are more likely to survive long enough to reproduce than those who do not have comparative advantage. The offspring of fitter individuals may inherit the genes that give them this advantage.

Answer 165

Those with stronger traits are more likely to succeed.

Answer 166

Plate tectonics is the scientific theory that explains the movement of Earth's outer shell, which is divided into several large plates.

Answer 167

Plate tectonics causes speciation, because species were physically separated, forced to adjust to their new conditions, and thus evolved to deal with the new environmental conditions.

Answer 168

Divergent, convergent and transformative.

Answer 169

A mass extinction is a sudden global decrease in the numbers of species over a relatively short period of time.

Answer 170

The IUCN Red List evaluates species' extinction risk

Answer 171

The number of mature individuals (reproduction capacity) Population size reduction Geographical range Degree of specialisation

Answer 172

Extinct Extinct in the wild Critically endangered Endangered Vulnerable Near threatened Least concern

Answer 173

Human causes Natural (non-human) causes

Answer 174

Volcanic Eruptions. Drought. Meteors. Glaciers and ice age. Competition and predation.

Answer 175

Human causes (HIPPO): Habitat destruction and fragmentation. Introduced species. Pollution. Practices of agriculture. Over-hunting.

Answer 176

Can prosecute violations of regulations in their jurisdictions.

Answer 177

Agreements are not legally binding under international law, but signatories are responsible for enforcement as GO’s.

Answer 178

Lobby for awareness of environmental issues.

Answer 179

A flagship species is a species selected to act as an ambassador, icon or symbol for a defined habitat, issue, campaign or environmental cause.

Answer 180

Charismatic species are usually defined as “popular, charismatic species that serve as symbols and rallying points to stimulate conservation awareness and action.”

Answer 181

A species on which other species in an ecosystem largely depend, such that if it were removed the ecosystem would change drastically.

Answer 182

In-situ, ex-situ, mixed

Answer 183

Protected areas are areas under legislation for in-situ conservation

Answer 184

Size, shape, corridors, proximity to other protected areas

Answer 185

Glaciers/ice caps Groundwater Permafrost Surface/atmospheric

Answer 186

Evaporation Freezing Melting Deposition (gas to solid) Sublimation (solid to gas)

Answer 187

Snow, stream, water in soil moisture (percolation) and groundwater flow into large bodies of water, such as lakes and the ocean.

Answer 188

Water evaporated from large bodies of water Water collectes in clouds Water precipitates and is fed back into the inputs (it becomes snow, groundwater, etc).

Answer 189

Humans alter the water cycle through extraction, landscape changes causing flash floods, deforestation increasing flood risk, urbanization preventing water permeation and increasing pollution, and agriculture leading to high water use and pollutant runoff.

Answer 190

The ocean circulates through a giant conveyor belt, which is also called thermohaline circulation.

Answer 191

The colder and the saltier the water is, it leads it to become denser. Water cools at the poles, sinks, travels to the equator through deep ocean currents, surfaces, warms, travels to the surface through surface currents and reaches the poles.

Answer 192

Water-born, water-washed, water-based and water-related insect vector

Answer 193

Diseases that occur when an individual drinks contaminated water.

Answer 194

Diseases that occur when there is indirect contact with contaminated water.

Answer 195

Diseases that occur when the route of entry into humans vary (ingested, worms, indirect contact).

Answer 196

These diseases spread by insects that breed in/near water.

Answer 197

Population growth. Average income increases. Increased demand for meat (water intensive product). Growth of industries. Increase in urbanization.

Answer 198

Less than 1700m3/person/year in a country.

Answer 199

Unsustainable use. Pollution of water. Inefficient use.

Answer 200

Reservoirs would store water for multiple uses, implement flood control, and allow for water quality management

Answer 201

Artificial Recharge increases groundwater levels, offering a solution to water scarcity by utilizing surface runoff or pumping from surface water

Answer 202

Rainfall Harvesting is a low-cost method to collect and use rainwater for domestic purposes, enhancing water availability without significant infrastructure.

Answer 203

Desalination produces drinkable water from seawater,

Answer 204

Redistribution transfers water from surplus to deficit areas, potentially alleviating local water shortages

Answer 205

Gray Water reuses household wastewater for non-potable purposes, reducing freshwater demand

Answer 206

Lowering consumption

Answer 207

Primary producers such as phytoplankton and seaweeds, which form the base of the food chain. Primary consumers include zooplankton, ciliates and larvae that eat the primary producers. Secondary producers are small predators such as small fish and young large fish species. Tertiary consumers are the top predators, such as large fish (tuna, sharks, etc), marine mammals (dolphins, seals and walruses) and birds (penguins, etc).

Answer 208

In shallow water nutrients mix (wind and currents). River inputs bring in more nutrients. Sunlight reaches the sea floor, which increases primary productivity.

Answer 209

Primary producers are phytoplankton and macrophytes. Primary consumers are zooplankton and water snails. Secondary consumers are fish, birds and frogs. Tertiary consumers are large fish (e.g. piranhas), large birds and mammals (otters and humans).

Answer 210

Inland/costal pollution Marine-based polution

Answer 211

Potential answers: Domestic sewage Industrial discharge Agricultural run-off Urban run-off Land development Accidental discharges Atmospheric inputs

Answer 212

Outfall pipes Materials dumped at sea Shipping activities Exploitation of resources

Answer 213

Potential answers: Reduced oxygen, toxic gases, and fish deaths from organic pollutants. Nutrient overload causing plant overgrowth, reduced light, biodiversity loss, dead zones, and health risks. Toxic metal accumulation, harming food chains. Synthetic chemicals damaging aquatic life and causing human health issues. Light blockage from solids suppressing plants. Oil spills leading to oxygen depletion and harming marine life. Pathogens causing health risks up the food chain. Noise and light disorienting marine animals. Invasive species disrupting ecosystems.

Answer 214

pH Temperature Suspended solids Dissolved oxygen Nutrients Presence of metals

Answer 215

Pathogens are organisms that cause disease to their hosts.

Answer 216

Transient pollutants are those that are dispersed prior to testing.

Answer 217

A microbial test is used when the water is being used for recreational/consumption purposes. This tests for the presence of certain bacteria that are prevalent in contaminated water (e.g. E. Coli).

Answer 218

To detect pathogens and transient pollutants.

Answer 219

Biological monitoring using indicator species. Biotic index (what organism is present). Microbial test

Answer 220

Replacing harmful chemicals Obtaining consent licences for wastewater discharge (quota) On-site treatment to meet standards prior to discharge.

Answer 221

Reducing pesticides/fertilizers, Managing organic waste Efficient irrigation Contouring/buffer zones.

Answer 222

Improving sewage treatment Buffer zones Water aeration

Answer 223

Soil is a mixture of minerals, organic matter, air and water.

Answer 224

A medium for plant growth Water storage/purification system

Answer 225

Climate Organisms Relief (physical characterists of the land surface) Parent material Age

Answer 226

Micro-organisms: Such as bacteria, algae and fungi. Macro-organisms: Such as earthworms, insects, mites and millipedes.

Answer 227

Minerals Organic matter Gases Water

Answer 228

It's components (air, water, minerals, organic matter).

Answer 229

Wind, water and erosion can loosen or remove layers of topsoil (leeching, erosion and blowing soil away). Plants intake nutrients and carbon dioxide from soil. Elements of soil (clay) can become outputs if animals consume them.

Answer 230

Leaching: Soluble materials move through the soil, mainly downwards, without changing their nature.

Answer 231

Evaporation Decomposition Leeching/evaporation

Answer 232

The O horizon is the organic horizon, and it is the top layer of soil. It includes all the DOM (dead organic matter) that is eventually turned into humus.

Answer 233

The A horizon is the topsoil and mineral layer. In this layer, clay has often been washed out and there is a high organic content layer (leading to a dark colour). The A layer is the topsoil, the area with the most biological activity.

Answer 234

The B horizon is the sub-soil. This means that there is an accumulation of minerals and particles that have been washed down from layers O and A. Plant roots are found here, but there are very small quantities of DOM.

Answer 235

The C horizon is the broken down parent material, which means it may have weathered and clumped.

Answer 236

Sand Silt Clay

Answer 237

Environmental conditions Access to vehicles/technology Financial resources EVS Government/political initiatives

Answer 238

Intensive commercial (crop) farming. Intensive animal farming. Organic farming. Subsistence farming. Intensive subsistence farming.

Answer 239

Follows the same model as intensive crop farming, maximises outputs by inputting costly resources. Intensive husbandry maximises output with confined spaces. Disease spread, ethical concerns, use of growth hormones/antibiotics and the fact that organic waste contaminates water systems.

Answer 240

General idea: Tends to be more aligned with monoculture (specialising in one crop) Techniques: The use of GMO’s (Genetically Modified Organisms), fertilisers, irrigation systems and mechanical equipment results in high (often unsustainable) yields. Environmental challenges, which include pesticides, fertilisers, high water use, monoculture (increases risk of contaminated crop), emissions from mechanical equipment, soil degradation and habitat loss.

Answer 241

General idea: Limits chemical/pesticide use. Techniques: Physical/biological pest control, use of natural fertilisers (manure, compost, etc) and polyculture farming (multiple crops). Livestock management: Organic feed, no routine drugs/growth hormones and open space with outdoor access.

Answer 242

General idea: Land is cleared by slash and burn, used until fertility declines, then abandoned for new areas. Techniques: Land management (slash and burn) and fallow periods (allowing land to regenerate before reusing). Challenges: Lack of sustainability causes fallow periods to shorten, leading to low crop production as a whole. Slash and burn techniques can grow out of control and cause wildfires.

Answer 243

For LEDCs (Least Economically Developed Countries), food waste is mainly attributed to pests, poor infrastructure and lack of refrigeration.

Answer 244

For MEDCs (Most Economically Developed Countries), food waste is mainly attributed to consumer behaviour and regulatory standards.

Answer 245

Population growth, increasing affluence, cultural status, rise in cheap meat production and awareness of the high protein content of meat.

Answer 246

Environmental degradation, increased water use/pollution and exacerbating impacts of climate change.

Answer 247

Legislation can be used to restrict certain substances (e.g. DDT) and set regulations for food production (controlled use of drugs/hormones, pesticides, etc). Reduction of food waste. Growing indigenous crops (crops adapted to low fertility and rainfall). Polyculture farming

Answer 248

Soil is considered a non-renewable resource, given the time it takes to develop.

Answer 249

Between 5.5 and 7.5

Answer 250

Erosion Chemical degregation Physical degregation

Answer 251

Urbanisation Overgrazing Deforestation Farming practices

Answer 252

Reduced soil fertility Increased flooding Desertification

Answer 253

Vegetation cover Terracing Furrow diking Conservation tillage Buffer strips Wind-breaking crops Water management Proper drainage Organic matter addition Crop rotation Limit animal numbers Rotational grazing

Answer 254

Nitrogen (78%) Oxygen (21%)

Answer 255

Troposphere Stratosphere Mesosphere Thermosphere

Answer 256

The troposphere is the level from sea level to 10km in the atmosphere.

Answer 257

The sun heating the atmosphere/earth Wind speeds Jet stream Weather Greenhouse effect

Answer 258

The stratosphere is the layer that extends from 10 to 50 kms above sea level. The ozone is in the stratosphere, and ozone particles absorb UV radiation from the sun.

Answer 259

The mesosphere is the layer of the atmosphere that ranges from 50 to 80 kms above sea level. There are no particles to absorb UV radiation, making it the coldest layer of the atmosphere (-100 degrees celsius).

Answer 260

The thermosphere is the top layer of the atmosphere. It extends from 80 - 500/1,000 kms above sea level.

Answer 261

The ozone layer protects organisms from harmful UV (ultraviolet) rays (radiation) emitted by the sun.

Answer 262

UV-A rays are the longest wavelength. Ozone is unable to absorb this radiation. UV-B rays are the second longest wavelength. Ozone absorbs most of the radiation, but some passes through to earth. UV-C rays are the shortest (highest energy) rays and ozone is able to absorb all this radiation.

Answer 263

Sunburn, and related effects (cataracts, skin cancer, ect). Immune-system suppression. Reduction in crop production. Lower levels of primary production in food webs (primary producers, e.g. phytoplankton). Reduction in forest productivity (exacerbating climate change, less carbon dioxide absorption).

Answer 264

Dobson Units (DU)

Answer 265

Chemicals can react with ozone (o3) and deplete it. This causes more harmful radiation to reach earth. These chemicals are called ODS (Ozone Depleting Substances). Often time, they include chlorine and bromine.

Answer 266

Chlorofluorocarbons are a type of ODS. They were used as coolants, propellants in aerosol, cleaning agents and for other miscellaneous purposes.

Answer 267

Spatial differences

Answer 268

Possible answers: International agreement (UN committees, etc). National legislations Public awarness

Answer 269

Air pollution is the introduction of harmful particulate matter into the air

Answer 270

Urban air pollution is matter that is introduced into the air through urban activities (burning of fossil fuels, driving, etc).

Answer 271

Natural (volcanos) Stationary (factory emissions) Mobile (train fumes)

Answer 272

Carbon dioxide Sulphur dioxide Nitrogen Oxides

Answer 273

Respiratory problems Eye irritation Acid rain

Answer 274

Respiratory irritation Photochemical smog Visibility reduction Particulate matter

Answer 275

Photochemical smog is a type of air pollution that forms when pollutants from vehicle emissions and industrial processes react in the presence of sunlight.

Answer 276

The chemical reaction occurs between nitrogen oxides (NOx) and volatile organic compounds (VOCs). It has hundreds of other chemicals but those are the main ones.

Answer 277

High emissions of pollutants High levels of insolation Light winds/rain Topography (valleys) Presence of thermal inversion

Answer 278

Changing human behaviour Economic incentives Technological changes

Answer 279

Acid deposition is the deposition of acidic substances from the atmosphere onto the Earth's surface, causing environmental harm.

Answer 280

Acidity refers to the level of hydrogen ions present in a substance and is expressed as pH.

Answer 281

Lower than pH 7

Answer 282

Primary pollutants sulphur dioxide (SO2) and nitrogen oxides (NOx) reacting in the atmosphere. They create the secondary pollutants of Sulphuric acid (H2SO4) and Nitric acid (HNO3). This causes pH of deposition to drop below 5.

Answer 283

Wet deposition occurs when pollutants are incorporated into clouds or precipitation.

Answer 284

Dry deposition occurs when gravity causes pollutants to become absorbed into plants or buildings.

Answer 285

Strong winds disperse pollutants, but also cause them to travel long distances. Light winds allow pollutants to accumulate.

Answer 286

It can lower the pH of water beyond levels suitable for the survival of aquatic organisms. The loss of these species can alter food chains/webs. pH being lowered causes the release of aluminium ions, which harms fish.

Answer 287

Acid deposition increases soil acidity (lowers productivity). Lower pH causes the release of aluminium ions, which harms plant roots. Overall, it lowers crop yield, productivity and plant damage.

Answer 288

Changing human behaviour (carpooling to reduce the amount of pollutants emitted into the air) Economic instruments (Carbon taxes) Technology (Solar panels for renewable energy) Legislation (Emission standards for vehicles/industries).

Answer 289

Fossil fuels are composed of coal, oil and natural gas, they supply the energy that society needs.

Answer 290

Fossil fuels are created from dead organic matter under pressure for millions of years.

Answer 291

Infrastructure is already established to rely on fossil fuels. E.g. rail links are connected to an electricity grid powered by coal. High energy content. Relatively cheap. Currently, relatively abundant.

Answer 292

Finite resources that are unsustainably used. Extraction of fossil fuels can destroy habits and reduce biodiversity. Transport and combustion of fossil fuels produces emissions Power plants require large volumes of water, which can compromise the biodiversity of aquatic ecosystems, and its discharge can cause thermal pollution.

Answer 293

Coal is the most abundant of all fossil fuels. It is extracted through mining, which can be hazardous to human health and safety.

Answer 294

Oil is another fossil fuel that is usually pumped from underground reservoirs, which can pollute underground aquifers and cause oil spills.

Answer 295

Natural gas is the fossil fuel that contaminates its environment the least. It is extracted from sub-surface rock formations via drilling (fracking). Fracking is a process in which water, sand and chemicals are pumped at high pressure through rocks, causing the release of natural gases.

Answer 296

Nuclear power is power generated by a nuclear reactor.

Answer 297

Low-level radioactive waste can be filtered and released into the environment little by little. However, solid and other waste needs to be carefully disposed of. In order to discard radioactive materials, most plants use underground repositories (storage). The concerns of this is that it can rupture.

Answer 298

Chernobyl and Fukushima

Answer 299

Nuclear power stations do not produce carbon dioxide, an exacerbator of climate change. Compared to fossil fuels, nuclear power causes fewer casualties (coal mining accidents or premature death from air pollution).

Answer 300

Generation of nuclear waste with high radioactive levels. Risk of nuclear disasters. Potential use of radioactive materials used to produce nuclear weapons. High capital cost and high decommissioning cost (when plant is created/dismantled).

Answer 301

Solar Wind Hydropower Biomass Geothermal Wave/tidal

Answer 302

Improvements in local air quality (less production of primary and secondary pollutants) Reduced greenhouse gas emissions.

Answer 303

Decline in fossil fuel reserves (drives price up). Technological developments improving efficiency of renewable energy and capital cost. Governmental support through economic incentives (subsidies). Increasing awareness of the climate impact of fossil fuels. Need to meet international energy targets.

Answer 304

Advantages: - They can be used in remote areas. - Low running cost. - Silent. - Does not emit pollutants when operating. Disadvantages: - Can only function off sunlight. - High capital cost. - Instalment emits carbon dioxide. - Energy needs storing.

Answer 305

Advantages: - Inexhaustible energy source. - Can be used in remote areas. - Once installed, does not pollute. - Operational cost is low. Disadvantages: - Wind-dependent - Noisy - Aesthetically displeasing - Can kill birds. - High cost (upfront) - Energy needs storing.

Answer 306

Hydroelectric power (HEP) is produced when water flows through a turbine connected to a generator.

Answer 307

Advantages: - Low running cost - Sustainable - Dams regulate the risk of flooding and provide an ecosystem - Opportunities for recreation. Disadvantages: - High capital cost - Dam construction can alter systems (human displacement, loss of habitat/species diversity, loss of sediment downstream, disruption of migratory fish patterns)

Answer 308

Geothermal power is power that is derived from geothermal energy. Geothermal energy is heat from the Earth, used to generate electricity or heat buildings.

Answer 309

Advantages: - Cheap to operate - Emits low levels of GHG - Somewhat reliable supply - Sustainable Disadvantages: - High capital cost - Poisonous gases trapped under the surface of the earth can be released - Limited to areas near volcanic activity.

Answer 310

It is generated by drilling wells into reservoirs filled with water and/or steam, and pushing that through pipes in order to spin turbines. The movement of these turbines generates electricity through a generator, which creates electricity.

Answer 311

Energy security is defined as “the uninterrupted availability of energy sources at an affordable price”.

Answer 312

The supply of energy meets the demand for energy. Reliable supply that is not interrupted (e.g. conflict) Affordable supply.

Answer 313

Possible answers: Political instability and/or conflict in a country/region. Accidents (industry) or natural disasters. Risk of terrorist attacks or faulty supply infrastructure. Exhaustion of resources.

Answer 314

Reducing imports (becoming more self-sufficienent) Diversifying energy sources. Promoting energy choices that favour conservation.

Answer 315

Availability Sustainability Scientific/technological developments EVS Economics

Answer 316

Climate is the average weather over the long term at a regional level (e.g. Temperature in North America over the years).

Answer 317

Weather refers to the conditions over a short period of time at a local level (e.g. Rain in Panama City on the 5th of February).

Answer 318

Solar radiation Tilting and orbiting of the earth

Answer 319

Greenhouse gases Volcanic activity Feedback cycles

Answer 320

Atmospheric circulations refer to the large-scale movement of air in the earth’s atmosphere.

Answer 321

Hadley cell: Extends from 0° (Equator) to 30° latitude in both hemispheres. Ferrel cell: Found between about 30° and 60° latitude in both hemispheres. Polar cell: Extends from around 60° latitude to the poles (90° North and South latitude).

Answer 322

Possible answers: - Water vapour - Ice albedo - Permafrost melting - Carbon Dioxide solubility - Cloud cover

Answer 323

- Plant photosynthesis - Cloud cover

Answer 324

Range shifts mean that with a change in climatic conditions, there is expected to be a general shift of biomes, with animals/plants moving towards the poles and upwards in elevation as the equator becomes hotter. Range shifts include biome shifts (alteration of habitats) and the extinction of less adaptive species.

Answer 325

Migration patterns will change, as migratory species usually move in response to seasonal changes. As seasonal changes alter, changes in migration and mating times, will potentially lead to mismatches in food availability.

Answer 326

Potential answers: Storm intensity. Sea level rise. Heatwaves. Food/water shortages. Environmental refugees.

Answer 327

Mitigation is defined as human intervention to reduce the source of greenhouse gas emissions or to enhance carbon sinks.

Answer 328

A carbon sink is anything that absorbs more carbon from the atmosphere than it releases.

Answer 329

Geo-engineering involves manipulating the earth’s environmental systems to counteract the impacts of climate change.

Answer 330

Carbon dioxide removal Solar radiation management

Answer 331

Land use management (reforestation, reducing deforestation). Carbon capture and storage Absorption by oceans (ocean fertilisation with nutrients, mechanical upwelling to increase photosynthesis by phytoplankton.)

Answer 332

Increasing earth’s surface reflectivity includes painting rooftops with white paint, cultivating high-albedo crops, covering deserts with reflective materials. It would result in a higher reflection of sunlight into space. The use of aerosol particles, in order to attract water molecules within clouds. It would result in enhanced cloud reflectivity, more sunlight reflected into space, potential reduction in global warming. Solar detectors in space would involve the deployment of solar deflectors or mirrors in space. It would result in reduced sunlight reaching earth and a potential decrease in global temperatures.

Answer 333

Adaptation is defined as an adjustment to actual/expected climate and its effects, aiming to moderate harm or exploit beneficial opportunities.

Answer 334

Mitigation is addressing the causes of climate change, whereas adaptation addresses the effects of climate change. The effects of mitigation can be seen on a global scale, whereas the effects of adaptation are at a local level. Mitigation is easy to measure (levels of atmospheric GHG), whereas adaptation is not.

Answer 335

Water conservation Desalination plants Bans on building in flood-prone areas Flood control (barriers, drainage improvements, diversion strategies) Infrastructure modifications to withstand floods.

Answer 336

Agricultural adaptation: development and use of crops resilient to climate changes, adjusting planting and harvesting times and water conservation techniques. Fisheries adaptation: reduce fishing intensity and catches, alongside the diversification of fisherman’s employment.

Answer 337

Expanding conservation areas. Creating corridors for species migration. Protecting vulnerable areas. Forest fire management.

Answer 338

Construction and reinforcement of seawalls and coastal defences. Contingency plans for floods. Assigned retreat and relocation areas for coastal populations.

Answer 339

Monitoring systems for health risks associated with climate change. Vaccination programmes. Public health education on climate-related health precautions.

Answer 340

Possible answers: Political and economic factors including public opinion, fear of stunting economic growth, fossil fuel dependence and the prioritisation of short-term benefits are all a barrier for implementing change. Implementation challenges, such as knowledge gaps, policy integration (poor incorporation), communication breakdowns, regulatory weakness, political instability/corruption, procrastination and financial/technological limitations all hinder change. These are especially prominent in LEDCs.

Answer 341

Possible answers: Knowledge sharing. Complementary strategies (mitigation and adaptation being integrated). Effective communication. Commitment/collaboration. Financial/logistical/technological support. MEDCs providing support for LEDCs.

Answer 342

Demography is the study of populations of any organism.

Answer 343

CBR (Crude Birth Rate) and TFR (Total Fertility Rate).

Answer 344

CDR (Crude Death Rate)

Answer 345

NIR (Natural Increase Rate) and the DT (Doubling Time)

Answer 346

The crude birth rate (CBR) is the number of births/1000 per year. OR It details how many babies are born each year for every thousand people in the population of a country.

Answer 347

CBR = Number of births/ Population x 1000

Answer 348

The total fertility rate (TFR) is the number of children a woman is expected to have in her lifetime:

Answer 349

The critical value of TFR is 2.2. A TFR greater than 2.2 in a country indicates an increasing population. A TFR of 2.2 in a country indicates a stable population. A TFR lower than 2.2 in a country indicates a decreasing population.

Answer 350

The infant mortality rate (IMR) is the number of babies that die in the first year of their life.

Answer 351

IMR = Number of deaths of children less than a year old/ Number of live births in the same year x 1000

Answer 352

The role of children in the labour force. The rates of urban living. Women's status. Lifestyle and cultural norms. Infant mortality rate. Pensions. Family planning/abortions. Religious beliefs/traditions. Government policy.

Answer 353

The crude death rate is the number of deaths per year per a thousand people of the population. It details how many people die each year for every thousand people in the population.

Answer 354

CDR = Deaths in one year/ total population x 1000

Answer 355

Income Education Access to food Availability of health care Water supply/sanitation Access to shelter

Answer 356

The rate of natural increase refers to the difference between the number of live births and the number of deaths occurring in a year

Answer 357

If fertility > mortality, fertility is positive. If fertility < mortality, fertility is negative.

Answer 358

NIR = (CBR - CDR) / 10

Answer 359

The doubling time is how long it will take a given population to double in size.

Answer 360

DT = 70/NIR

Answer 361

The malthusian theory suggests that population growth outpaces agricultural production, leading to famine, disease, and war as natural checks on population.

Answer 362

Emphasises not only the potential for overpopulation to cause scarcity and conflict but also advocates for population control measures, including family planning and contraception, to prevent these outcomes.

Answer 363

Overpopulation refers to a situation where the number of people exceeds the capacity of the environment to support life at a sustainable level.

Answer 364

Rising price of grains (increased demand). Unsustainable population levels exceeding the carrying capacity of regions. Deforestation for urban expansion, agriculture, and mining. Overexploitation of oceans depleting fish stocks. Topsoil depletion due to over-cropping.

Answer 365

Expansive, constrictive and stationary pyramids.

Answer 366

Expansive pyramids are characterised by a broad base, indicating a high birth rate and a rapidly growing population. These are common in developing countries. They show larger numbers or percentages of the population in the younger age groups, usually with each age group smaller in size or proportion than the one born before it.

Answer 367

Constrictive pyramids are characterised by a narrow base, indicating a decrease in fertility as less people have children. These are most common in developed countries.

Answer 368

Stationary pyramids display relatively equal numbers across age groups, although older age groups logically have lower populations. This indicates low birth rates and low death rates, suggesting a stable population.

Answer 369

Demographic transition model (DTM) is a theoretical framework that describes the transition of a country from high birth/death rates to low birth/death rates through stages of economic development.

Answer 370

Pre-industrial (high stationary) stage: Characterised by high birth and death rates, resulting in slow population growth. The economy is predominantly agricultural, and families tend to have many children for labour purposes. Transitional (early expanding) stage: Death rates begin to decline significantly due to improvements in healthcare, sanitation, and nutrition, but birth rates remain high. This leads to rapid population growth. Economies start to transition from agriculture to industrialization. Industrial (late expanding) stage: Birth rates start to decline, catching up with the decline in death rates, as a result of changes in societal values, increased access to contraception, and women entering the workforce. The population growth rate begins to slow down. The economy sees significant industrial growth. Post-industrial (low stationary) stage: Both birth and death rates are low, stabilising the population growth at a low level. The economy is characterised by more service-oriented industries, and there is a high standard of living.

Answer 371

In the first stage, there is a high CBR and CDR. In the second stage, there is a high CBR and a falling CDR. In the third stage, there is a falling CBR and CDR. In the fourth stage, there is a low CBR and CDR.

Answer 372

Any government policy that either directly or indirectly impacts fertility and mortality are known as development policies.

Answer 373

Definition: Indirect government policies impacting fertility and mortality rates are measures not directly targeting these outcomes but influence them by affecting socio-economic conditions, healthcare access, education, and quality of life. Example: An example of an indirect government development policy are the Millennium Development Goals (MDGs) that were established by the UN in 2000. They are a set of eight international development goals. They include goals such as: "Ensure that, by 2015, children everywhere, boys and girls alike, will be able to complete a full course of primary schooling” and “Eliminate gender disparity in primary and secondary education, preferably by 2005, and in all levels of education no later than 2015”. Once education levels and the status of women change, this will indirectly impact fertility rates.

Answer 374

Direct governmental policies that impact demographics are related to fertility. Direct governmental development policies may be pro-natalist (ones that increase fertility rates) or anti-natalist (ones that decrease fertility rates.)

Answer 375

Anti-natalist strategies include: Tax/welfare disincentives. Raise awareness. Pro-natalist strategies include: Tax/welfare incentives.

Answer 376

Natural capital is the set of renewable and non-renewable natural resources of an ecosystem.

Answer 377

Economic Cultural/spiritual Environmental capital Technological capital

Answer 378

Economic capital: A resource that is tangible that has monetary value (E.g. gold has a known value according to weight and quality (carat)). Technological advancements, economic conditions, and environmental considerations will alter the value of economic capital.

Answer 379

Cultural/Spiritual capital represents the heritage and spiritual significance of sites and traditions valued within a culture or religion (E.g. Uluru (a rock formation in Australia) is sacred to Aboriginal Australians, representing spiritual capital).

Answer 380

Environmental capital consists of natural resources and ecosystems that support life and economic activity (E.g. The Amazon Rainforest is a form of environmental capital for Colombia, Brazil and other South-American countries).

Answer 381

Technological capital is when technology itself becomes a form of capital that can either enhance or deplete natural capital (E.g. Sources of renewable energy).

Answer 382

Solid domestic waste (SDW) is also known as rubbish, trash and garbage. OR It is the everyday items that are discarded by the human population.

Answer 383

Organic material. Paper. Plastics. Glass. Metals. Hazardous.

Answer 384

A landfill site is a large hole in the ground where waste materials are buried. In order for landfills to be non-hazardous, they must be lined with clay/synthetic flexible membrane to avoid the absorption of waste into ground water, they must be as small as possible, waste must be regularly compacted and it must be daily covered with soil in order to avoid lighter waste from blowing away. The advantages of landfills are that it is a cheap method of waste disposal and they create jobs for local communities. The disadvantages of landfills are that they emit dangerous gases during decomposition, it can cause the pollution of groundwater, their span is limited, are aesthetically unpleasing and increase the spread of disease.

Answer 385

Incineration is a waste disposal method in which waste is combusted (burnt). After waste is initiated, it is converted into ash (what is left after the burn), flue gas (the emission from combustion plants, comprising the byproducts of fuel and combustion air, along with residuals like ash) and heat. The advantages of incinerating waste are it reduces the volume of waste, destroys pathogens in waste and it can be used to generate electricity. The disadvantages of incinerating waste are it emits varying levels of heavy metals, releases carcinogenic pollutants, causes property devaluation, has a high capital cost and takes away local jobs provided by landfills.

Answer 386

Reduce the amount of waste being produced in the first place. Reuse an item multiple times, either for the original purpose or for some other purpose. Recycle the material of the object by transforming it into the raw material for a new object. The advantages of this method are that it reduces landfill waste, conserves resources and encourages changes in human behaviour. The disadvantages of this method are that it is inefficient and requires individual action, which does not always occur.

Answer 387

Compositing is the process of turning organic waste materials into a nutrient-rich soil material through natural decomposition. In order to compost, organic waste has to be collected and stored until it decomposes, where it can act as a soil fertiliser. It combines the three R’s. Removing organic material from the waste stream reduces the amount going into landfills. The decomposed organic matter is reused and recycled as soil fertiliser. The advantages of composting is that it reduces waste, is cost-effective and improves soil health. The disadvantages of composting is that it is time consuming, requires space and not all food can be composted (e.g. meat and dairy will rot, producing a foul odour).

Answer 388

The carrying capacity of the human population discusses whether or not a population is living sustainably. If a population is living sustainably, there are enough natural resources to provide for the population without causing environmental damage.

Answer 389

Waste assimilation: The environment's capacity to absorb, neutralise, or recycle waste impacts human carrying capacity by determining the limits of sustainable pollution and waste production. If the waste produced by a population is greater than the environment can absorb, then the carrying capacity of that population will be lowered. Range of resources: The diversity and availability of natural resources, from water to minerals, influence carrying capacity by affecting the supportable population size based on resource needs. Imports: The ability to import resources from other regions affects carrying capacity by potentially allowing a population to exceed its local environmental limits through external resources. Technology: Technological advancements impact carrying capacity by improving efficiency in resource use, waste management, and the ability to harness new resources.

Answer 390

An ecological footprint is a measure of the amount of land that is needed to support a population.

Answer 391

Biocapacity is the biological capacity (supply) of an area/region/country to generate the resources and absorb the wastes of a given population. Demand looks at how much productive land is needed (demanded) to supply our resources, space for buildings and roads, and to soak up the waste we create.

Answer 392

Energy, travel and goods: This component calculates the footprint associated with energy consumption, including electricity and fuel for transportation and the production of consumer goods. Settlement and infrastructure: This measures the land area needed for housing, urban development, and public infrastructure like roads and buildings. Food and fibre: This part assesses the amount of land and water required to produce the food we eat and the natural materials (like cotton) we use for clothing and other goods. Seafood: This component estimates the ecological impact and necessity of harvesting seafood from oceans and freshwater bodies.

Answer 393

Carbon footprint is the total amount of greenhouse gas (GHG) emissions caused by an individual, city, event, flight, country etc. GHG are emitted through transport, land clearance production and consumption of all goods. Water footprint is the amount of water in an EF. This includes the water you use directly (washing and drinking) and indirectly such as the amount of water it takes to grow your food. Food footprint takes into account the land used in food production (crops, grass, animal feed), the land needed to absorb carbon emissions produced during food production and the sea area for fishing.

Answer 394

Ecological footprints are measured in gha/person: Gha = global hectare.

Answer 395

A biocapacity deficit means that there is a greater demand for natural resources than the available supply, meaning the EF indicates that the given population is living unsustainably. A biocapacity remainder means that there is a greater supply of natural resources than the demand, meaning the EF indicates that the given population is living sustainably.