Mangrove swamps contain a high concentration of organic matter in their waterlogged sediment due to slow rates of decomposition.
Explain what is meant by the term decomposer.
Detritus, consisting of fallen mangrove leaves, is consumed by mangrove crabs. These crabs are then hunted and eaten by reef herons. Use this information to draw a food chain for these organisms.
Environmental scientists can determine the percentage of organic matter in aquatic sediments. The method involves thoroughly drying a sample of sediment and then heating it at high temperatures to combust all organic material. The following formula is used:
Percentage of organic matter=mass of dried sediment−mass of combusted sedimentmass of dried sediment×100 \text{Percentage of organic matter} = \frac{\text{mass of dried sediment} - \text{mass of combusted sediment}}{\text{mass of dried sediment}} \times 100 Percentage of organic matter=mass of dried sedimentmass of dried sediment−mass of combusted sediment×100An orchid smuggler is suspected of entering a protected mangrove sanctuary. Sediment samples were taken from the sanctuary's restricted path and from the boots of three suspects (A, B, and C).
| Sediment from | Mass of dried sediment in g\text{g}g | Mass of combusted sediment in g\text{g}g | Percentage organic matter |
|---|---|---|---|
| Mangrove sanctuary path | 15 | 12 | 20 |
| Boot of Suspect A | 5 | 4.1 | 18 |
| Boot of Suspect B | 5 | 4.0 | 20 |
| Boot of Suspect C | 5 | 4.3 |
Use the formula to calculate the percentage of organic matter in the sediment from the boot of Suspect C.
Which suspect is most likely to be the orchid smuggler?
The legal team of the accused suspect argued that this sediment analysis is not reliable. Suggest one biological or experimental reason why this analysis may not be reliable.
