A coastal sediment budget
Change incoming sediment and local retention; trace gains and losses between two beaches.
Predict the effect before changing a value. Keep other values fixed, then compare the result and explain the relationship.
Explain and challenge the result
Compare with discussion guidance
Increasing retention gains material on A while reducing supply to B. Added sediment can change the total budget; a barrier redistributes it. Real transport varies with waves, tides, sediment size and available stores.