Certainly! Let's go through the steps to answer each part of the investigation regarding the water holding capacity of different soil samples.
### 8.1 Identifying Variables
#### (a) Dependent Variable:
The dependent variable is what you measure or observe in the experiment. In this investigation:
- Dependent variable: Water holding capacity of soil samples.
### 8.2 Identifying Variables
#### (b) Independent Variable:
The independent variable is what you change or control in the experiment to see how it affects the dependent variable. In this investigation:
- Independent variable: Type of soil.
### 8.3 Soil with the Lowest Water Holding Capacity
Identify the soil type that has the lowest water holding capacity. Based on general knowledge (since specific data isn't provided):
- Soil type: Sandy Soil.
### 8.4 Ways to Increase Reliability
To ensure that the investigation produces reliable results, consider the following methods:
1. Repeat the experiment multiple times: Performing the experiment several times helps to ensure that the results are consistent and not due to random chance.
2. Use a larger number of soil samples: Testing a larger number of soil samples increases the representativeness of the results, reducing the effect of outliers or anomalies.
### 8.5 Effect of Waterlogging on Plant Roots
If the soil becomes waterlogged, plant roots might face several problems:
- Explanation: If the soil becomes waterlogged, plant roots may experience oxygen deficiency. This can lead to root rot and reduced nutrient uptake, ultimately harming or killing the plant.
### Factors to Keep Constant
To maintain a fair test, certain conditions should be kept constant:
1. Amount of water added to each soil sample: Ensures that each soil type receives the same treatment.
2. Environmental conditions such as temperature and light exposure: Keeps external influences consistent, ensuring any differences in water holding capacity are due to the soil type alone.
By maintaining these conditions, you ensure that the experiment is controlled and the results are valid. This detailed approach ensures a thorough understanding of how different soil types affect water holding capacity.
