Ecosystem services are the benefits that humans receive from natural ecosystems. These services include carbon storage, water purification, flood prevention...
Question 1 Report
Ecosystem services are the benefits that humans receive from natural ecosystems. These services include carbon storage, water purification, flood prevention and food provision. A research team evaluated the services provided by four major ecosystem types to assess their conservation priority. Table 1.3 shows the ecosystem services provided by four different ecosystems.
| Ecosystem service | Tropical rainforest | Coral reef | Wetland | Grassland |
|---|---|---|---|---|
| Carbon storage / tonnes C per hectare | 250 | 30 | 200 | 50 |
| Biodiversity (species per hectare) | Very high | Very high | High | Moderate |
| Water purification | Moderate | Low | Very high | Moderate |
| Flood prevention | High | Moderate | Very high | Low |
| Food provision | Moderate | High | High | Very high |
| Estimated economic value / USD per hectare per year | 5 264 | 352 249 | 25 682 | 2 871 |
Fig. 1.3 shows the carbon storage data from Table 1.3.
(a) State which ecosystem has the highest estimated economic value per hectare per year. [1]
(b) Compare the ecosystem services provided by tropical rainforests and wetlands, using data from Table 1.3. [4]
(c) Explain why coral reefs have the highest economic value per hectare despite having lower carbon storage than rainforests. [4]
Answer Details
(a) Ecosystem with the highest economic value per hectare per year [1]
The coral reef, with an estimated economic value of 352 249 USD per hectare per year. [1]
(b) Comparison of ecosystem services: tropical rainforests vs wetlands [4]
- Tropical rainforests store more carbon (250 tonnes C per hectare) than wetlands (200 tonnes C per hectare). [1]
- Both have high biodiversity, though rainforests are rated "very high" compared to "high" for wetlands. [1]
- Wetlands provide much higher water purification services (rated "very high") compared to rainforests (rated "moderate"). Wetlands act as natural filters, trapping sediment and breaking down pollutants. [1]
- Wetlands also provide greater flood prevention (rated "very high" compared to "high" for rainforests). Wetlands absorb and store excess water during heavy rainfall, releasing it slowly and reducing downstream flooding. [1]
Overall, the two ecosystems provide complementary services: rainforests are stronger in carbon storage and biodiversity, while wetlands excel in water-related services (purification and flood prevention).
(c) Why coral reefs have the highest economic value despite lower carbon storage [4]
- Coral reefs support extremely valuable fisheries that provide food and livelihoods for millions of people in coastal communities globally. [1]
- They provide coastal protection by absorbing wave energy, reducing the impact of storms and erosion. Replacing this natural defence with artificial structures (sea walls, breakwaters) would cost billions of dollars. [1]
- Coral reefs generate very high tourism income through activities such as diving, snorkelling and boat tours. Reef tourism is a major source of revenue for many tropical island nations. [1]
- The high biodiversity of coral reefs supports pharmaceutical research and the discovery of novel compounds with medical applications, giving them significant commercial and scientific value. [1]
Economic value captures more than just carbon storage; it reflects the full range of goods and services an ecosystem provides, including provisioning (food), regulating (coastal protection), cultural (tourism) and supporting services.
Download The App On Google Playstore
Everything you need to excel in your exams
