What is the effect of pressure on water potential? Pressure potential is positive or negative?

Explanation

### Step-by-Step Solution:

1. **Understanding Water Potential**:
- Water potential is defined as the potential energy of water per unit volume relative to pure water in reference conditions. It quantifies the tendency of water to move from one area to another.

2. **Factors Affecting Water Movement**:
- Water can move due to several factors including osmosis, gravity, pressure, and matrix effects (like capillary action). These factors influence how water moves within plants, animals, and soil.

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