What are examples of soil degradation (physical, chemical, biological), causes of soil degradation, control measures for surface runoff, and issues addressed by the National Water Act of South Africa?

Here are the answers to your questions:

2.1.1 Other examples of degradation represented by letters A, B, and C are:

• A (Physical): Soil compaction
• B (Chemical): Soil acidification
• C (Biological): Loss of soil organic matter

2.1.2 Two agricultural practices that cause soil degradation in agricultural land are:

• Overgrazing
• Excessive tillage/ploughing

2.1.3 Two control measures that can be implemented to reduce surface runoff in arable lands are:

• Contour ploughing
• Cover cropping

2.1.4 Two main issues addressed by the National Water Act of South Africa are:

• Ensuring equitable access to water for all citizens.
• Promoting the sustainable use and protection of water resources for present and future generations.