Plants Flashcards
Limiting factors
A factor that limits the rate of reaction
Human effects:
Trampling
In a particular area of land trampling by humans or cattle can lead to an uneven distribution of plants.
Habitat destruction
This could include deforestation or clearing of land for development or agriculture.
Pollution
Acid rain can cause soils to become to acidic, killing some plants and inhibiting the growth of others.
Use of chemicals
Chemicals used include pesticides, fungicides, herbicides, fertilizers and liming. These all affect the growth and distribution of plants, and are likely to reduce biodiversity in a natural habitat.
Over - harvesting (affects of growth)
The depletes the soil of nutrients, making it difficult for plants to grow.
Monoculture
This involves growing only one type of plant in a particular field, which keeps depleting the soil of the same minerals, which are essential for healthy plant growth.
Soil PH
Plants are sensitive to changes in PH, most grow best in neutral or slightly acidic soil.
Aeration
Introducing air into the soil
Aeration of the soil is important for the healthy growth of plants as oxygen is needed.
1. For plants to respire
2. For microorganisms to respire
3. To help plants to absorb water and nutrients
4. To help prevent toxins forming in the soil
5. To help prevent plants from contracting diseases.
Light intensity
Sunlight is necessary for plants to be able to produce plant food by photosynthesis.
Plants grow more quickly in summer when there is more sunlight, usually plants grow better in unshaded areas than in shaded areas.
Sampling techniques
They are used to study the distribution of plants in a particular habitat.
Importance of random sampling
- Take samples at regular distances across the habitat
- Use a computer to generate random numbers to plot co ordinates in the habitat at which to take samples
- Select co-ordinates on a map and use a GPS system to find the exact position in the habitat at which to take samples.
