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Secondary 4 · Biology
Ecology and sustainability · Sustainability and global change

Sustainable development

The Dominican Republic imports a large share of what it consumes: fuel, wheat, cooking oil, and many other products. To turn that idea from an impression into a measurable fact, environmental science uses indicators such as the ecological footprint.

Sustainable development and environmental impact

Imagine that a company cuts down the forest on a hillside in the Cordillera Central and makes an enormous profit that year. But the slope is left eroded, the river fills with sediment, and the community is left without income for decades to come. How can we use resources today without sacrificing the well-being of the future?

Venn diagram with three circles representing the environmental, economic, and social dimensions of development; sustainable appears in their central intersection. environmental economic social sustainable
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Define sustainable development in your own words and describe a decision that your municipality could make (regarding transportation, energy, or waste management) that…

Define sustainable development in your own words and describe a decision that your municipality could make (regarding transportation, energy, or waste management) that is consistent with this concept, justifying your answer.

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Differentiate between the concepts of environmental impact and ecological footprint, using the construction of a major motorway through a rural area as an example.

Differentiate between the concepts of environmental impact and ecological footprint, using the construction of a major motorway through a rural area as an example.

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The ecological footprint

It is an environmental indicator: a number that summarizes a complex situation so it can be measured and compared. Its advantage is that very different impacts (burning gasoline, eating rice, building a house) are expressed in the same unit, the global hectare.

Six components of the ecological footprint, carbon, cropland, grazing land, fishing, forest, and built-up land, that add up in a single unit: global hectares. carbon cropland grazing fishing forest land built-up everything is expressed in the same unit: global hectares (gha)

Its main components are:

  • Carbon footprint: the area of forest needed to absorb the $\text{CO}_2$ we emit by burning fuels.

  • Cropland: land to produce rice, cassava, cacao, sugarcane, and other foods.

  • Grazing land: land for the livestock that provides meat and milk.

  • Fishing: the marine and freshwater area needed for the fish we consume.

  • Forest: land for wood, charcoal, and paper.

  • Land occupied by infrastructure: land taken up by houses, streets, and roads, which no longer produces anything.

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Explain what the ecological footprint measures and what unit it is expressed in. Name two everyday activities that increase it and two that reduce it, giving reasons for…

Explain what the ecological footprint measures and what unit it is expressed in. Name two everyday activities that increase it and two that reduce it, giving reasons for each.

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Name the main components of the ecological footprint (carbon footprint, cropland, grazing land, fishing grounds, forest and land occupied by infrastructure) and explain…

Name the main components of the ecological footprint (carbon footprint, cropland, grazing land, fishing grounds, forest and land occupied by infrastructure) and explain what two of them, of your choice, consist of.

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Order these ways of getting to school from smallest to largest ecological footprint and justify the order: cycling, driving alone, taking the city bus and car-sharing…

Order these ways of getting to school from smallest to largest ecological footprint and justify the order: cycling, driving alone, taking the city bus and car-sharing between four people.

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Biocapacity and ecological deficit

A municipality has enough fertile soil and water to supply 30,000 inhabitants, but 80,000 people live there with growing consumption. Where does the rest come from, and how do we measure that gap?

Bar chart contrasting a tall ecological footprint bar with a shorter biocapacity bar, highlighting the vertical difference as the ecological deficit. footprint biocapacity deficit

A country with a persistent deficit, as is often the case for the Dominican Republic, covers what its territory does not produce by importing products and using the resources of other territories, or by drawing down reserves that do not renew at the pace of consumption.

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Define biocapacity and explain how it differs from the ecological footprint, indicating the relationship between the two when a territory lives beyond its means.

Define biocapacity and explain how it differs from the ecological footprint, indicating the relationship between the two when a territory lives beyond its means.

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Explain what a country's ecological deficit is and discuss what it implies that the Dominican Republic has a persistent deficit: where do the resources that its own…

Explain what a country's ecological deficit is and discuss what it implies that the Dominican Republic has a persistent deficit: where do the resources that its own territory does not produce come from?

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The diagram compares the ecological footprint and available biocapacity per inhabitant of a city. Calculate its ecological deficit per inhabitant (the section marked…

The diagram compares the ecological footprint and available biocapacity per inhabitant of a city. Calculate its ecological deficit per inhabitant (the section marked with '?') and explain what this result means.

4.2 gha/inhabitant 1.6 gha/inhabitant ? ecological footprint biocapacity
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Explain what the ecological debt that rich countries hold with impoverished countries is, and relate it to the flows of raw materials (minerals, food, energy) and to the…

Explain what the ecological debt that rich countries hold with impoverished countries is, and relate it to the flows of raw materials (minerals, food, energy) and to the location of environmental impacts.

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Comparing footprints and the limits of the indicator

One planet of biocapacity versus almost three Earths needed if the whole world's population consumed like a developed country. biocapacity 1 planet ≈3 planets needed

The footprint changes a lot depending on each person's decisions: diet (beef needs much more land, water, and energy than grains and beans), transportation, and housing. Two people with the same income can have very different footprints.

Virtual water

Virtual water is the water used to produce a food or a product, even though you can't see it in the product. It is "hidden" in what we eat. Producing 1 kg of beef requires about $15\,000\ \text{L}$ of water, and 1 kg of wheat about $1\,500\ \text{L}$. That is why a meat-rich diet has a larger water footprint than one based on grains.

How many planets would we need

The same reasoning explains Earth Overshoot Day: the date in the year when humanity has already used up what the planet can regenerate in 12 months. If we need 2.9 planets, that day falls well before the end of the year.

Footprint and the Human Development Index

The Human Development Index (HDI) measures a country's well-being with a single number between 0 and 1. It combines three things: health (life expectancy), education (years of schooling), and income per person (GDP per capita). The closer to 1, the higher the human development.

GDP and the HDI measure well-being and wealth, but they do not say how much nature is used up to achieve them. That is why they are compared with the ecological footprint and the water footprint. A country is more sustainable when it reaches a high HDI with a moderate footprint, close to the planet's biocapacity per person (about $1.6\ \text{gha}$).

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Order these three diets from smallest to largest ecological footprint and justify the order based on the land area, water, and energy each requires: vegetarian diet,…

Order these three diets from smallest to largest ecological footprint and justify the order based on the land area, water, and energy each requires: vegetarian diet, diet rich in beef, and Mediterranean diet.

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Producing $1\ \text{kg}$ of beef requires about $15\,000\ \text{L}$ of water and producing $1\ \text{kg}$ of wheat about $1\,500\ \text{L}$. Calculate the water saved in…

Producing $1\ \text{kg}$ of beef requires about $15\,000\ \text{L}$ of water and producing $1\ \text{kg}$ of wheat about $1\,500\ \text{L}$. Calculate the water saved in a year if a person replaces a weekly kilo of beef with a kilo of wheat, and comment on what this "virtual water" contained in the diet represents.

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Analyze the following socio-ecological indicators for three fictitious countries: Country A: GDP per capita = $\text{RD\$}\ 44\,000$; Ecological footprint = $6.5\…

Analyze the following socio-ecological indicators for three fictitious countries:

  • Country A: GDP per capita = $\text{RD\$}\ 44\,000$; Ecological footprint = $6.5\ \text{gha/capita}$; Water footprint = $2\,400\ \text{m}^3\text{/capita/year}$; HDI = $0.93$.

  • Country B: GDP per capita = $\text{RD\$}\ 17\,000$; Ecological footprint = $2.2\ \text{gha/capita}$; Water footprint = $1\,150\ \text{m}^3\text{/capita/year}$; HDI = $0.82$.

  • Country C: Suffered a major industrial disaster with toxic spills that flooded a natural park; during the subsequent two years, its GDP per capita grew by $3.8\ \%$ annually due to decontamination work, compensation payments, and infrastructure reconstruction.

  1. a) Using the case of Country C, refute the statement that «continuous GDP growth is synonymous with sustainable development». Identify which structural flaw of traditional economic accounting is exposed.
  2. b) Compare the profiles of countries A and B. Argue which of the two is closer to a model of genuine sustainability when relating quality of life to ecosystem burden.
  3. c) Select two complementary indicators (for example, the Planetary pressures-adjusted Human Development Index and the Water or Material Footprint) and technically justify what critical information they provide that GDP completely ignores.
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The average biocapacity of the planet is approximately $1.6\ \text{gha/capita}$. In a developed country (A), the average ecological footprint reaches…

The average biocapacity of the planet is approximately $1.6\ \text{gha/capita}$. In a developed country (A), the average ecological footprint reaches $4.7\ \text{gha/capita}$, while its own territorial biocapacity is $1.4\ \text{gha/capita}$. In a developing country (B), the footprint is $1.1\ \text{gha/capita}$ and its territorial biocapacity is $2.6\ \text{gha/capita}$.

  1. a) Calculate how many planet Earths would be needed if the entire world population adopted the consumption pattern of country A. With that data, calculate with justification on which day of the year (Earth Overshoot Day) humanity would exhaust the regenerative resources of the planet under such a pattern.
  2. b) Calculate the ecological deficit or reserve of both countries (territorial biocapacity minus footprint). Explain, in biogeochemical and trade terms, how country A manages to maintain consumption far exceeding its local biological capacity without immediately collapsing.
  3. c) Assess the outcome from the perspective of global equity and ecological debt: what long-term biophysical consequences does the consumption pattern of country A have for country B and for the biosphere as a whole?
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A large intensive agro-industrial complex located in a Mediterranean basin claims in its environmental report that it has reduced its ecological footprint by $30\ \%$ in…

A large intensive agro-industrial complex located in a Mediterranean basin claims in its environmental report that it has reduced its ecological footprint by $30\ \%$ in five years because it electrified its machinery using solar energy and replaced plastic packaging with certified forest cellulose derivatives. However, the technical report of the basin warns that during that same period the company depleted local aquifers due to overexploitation of irrigation wells, increased nitrate contamination in groundwater, and caused a $70\ \%$ decline in steppe bird populations due to the removal of hedges and field margins.

  1. a) Explain why the standard ecological footprint methodology does not reflect the severe impact on the aquifer or on the local wildlife. Identify two inherent biases or limitations of this indicator when assessing comprehensive environmental health.
  2. b) Select two complementary indicators (such as the gray water footprint or biological integrity/biodiversity indices) and justify how they would accurately measure the impacts that the ecological footprint has omitted in this case.
  3. c) Design a proposal for a sustainability "dashboard" for this agricultural region: define three irreplaceable biophysical axes and establish for each one a criterion or threshold that prevents improvement in one variable from masking the critical degradation of another.
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Reducing the footprint: efficiency, rebound, and offsetting

We already know how to measure the footprint. How do we really reduce it? There are two common traps: thinking that becoming more efficient is enough, and thinking that everything can be offset without ceasing to emit.

Example: a car that uses less gasoline per kilometer makes traveling cheaper, and people drive more kilometers. Something similar happens with LED bulbs: they use little power, so they get left on for more hours and more lights are installed. Efficiency alone does not reduce the footprint. It needs to be accompanied by other policies, such as fuel taxes, maximum consumption standards, or cities with good public transportation and short distances.

You reduce first and, only with what cannot be avoided, you offset. Sinks (forests, mangroves) absorb carbon, but slowly. Basing the goal on buying credits has risks: they may not be fulfilled (the planted tree dies), emissions continue just the same, and responsibility is shifted somewhere else.

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An urban association of municipalities sets a goal of achieving net-zero emissions by 2035. In its greenhouse gas inventory, it records…

An urban association of municipalities sets a goal of achieving net-zero emissions by 2035. In its greenhouse gas inventory, it records $200\,000\ \text{t CO}_2\text{e/year}$, originating from residential heating, cooling, and electricity ($45\ \%$), fossil-fuel motorized transport ($35\ \%$), and waste management and indirect consumption ($20\ \%$). The plan proposed by the managers consists of reducing emissions by $5\ \%$ through awareness campaigns and purchasing carbon credits on the international market (financing forest monocultures on other continents) to offset the remaining $190\,000\ \text{t CO}_2\text{e/year}$.

  1. a) Evaluate this plan according to the climate mitigation hierarchy. Reason why offsetting before or in a greater proportion than reducing constitutes a serious technical and methodological failure.
  2. b) Critically analyze the massive purchase of forest carbon credits, pointing out two characteristic biophysical or governance problems (for example, permanence against disturbances, questionable additionality, or emissions leakage).
  3. c) Redesign the association's decarbonization plan by establishing a deep, structural reduction measure for each of the four key sectors (buildings, urban mobility, resource management/consumption, and local natural carbon sinks), justifying its technical effectiveness.
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The Jevons paradox or rebound effect: when cars use less fuel per kilometer, people tend to drive more kilometers and the savings fade away. a) Explain the mechanism of…

The Jevons paradox or rebound effect: when cars use less fuel per kilometer, people tend to drive more kilometers and the savings fade away. a) Explain the mechanism of the rebound effect with another example (LED lighting, efficient household appliances). b) Discuss why efficiency on its own does not reduce the footprint unless it is accompanied by other policies. c) Propose two policies (pricing, regulations, urban planning) that prevent the rebound.

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Back to the beginning: when we say that the Dominican Republic depends on imports, we are expressing that its ecological footprint exceeds its biocapacity: it lives in ecological deficit and obtains the rest of its resources from other territories on the planet.

Summary

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