Two equal plots of a wildflower meadow contain the same plant species and have similar conditions. At the end of each summer, both plots are cut.
The cut plant material is spread over plot P but is removed from plot Q. No fertiliser is added to either plot.
After four years, the plants in plot P produce a greater dry mass than the plants in plot Q.
Explain why the plants in plot P produce a greater dry mass than the plants in plot Q.
101 exam-style questions on Edexcel GCSE Biology 9.3 Material cycles and decomposition, covering 9.3.1 Cycling of materials through ecosystems, 9.3.2 The carbon cycle, 9.3.3 The water cycle, 9.3.4 The nitrogen cycle, 9.3.5 Indicator species and pollution, 9.3.6 Decomposition in preservation and composting, and 9.3.7 Rate changes in decay of biological material. Each one has a worked solution and a mark scheme showing where the marks go.