1. BALANCE OF NATURE bilogy form two tanzania

BALANCE OF NATURE TZ

1. TOPIC 3: BALANCE OF NATURE

2. The natural environment Nature comprises of living things and non-living thing. The living part of nature is known as biotic component of the environment while the non-living part of the nature is known as abiotic component of the environment. The term natural environment refers to the immediate surroundings of an organisms which include other living things and non-living things.

3. Terms used to describe a natural environmnet Ecology: Ecology is the study of organisms in relation to their environment. Ecology is a branch of biology, which deals with inter- relationsip between living organisms and their surroundings. Environment: Environment refers to the immediate surroundings of an organisms, which affect to and with which it may interact. The environment of organisms include both the living and non-living things.

4. Biosphere: Biosphere is the part of the planet earth which is inhabited by living organisms. This includes the land, the waters and air. It is also known as ecosphere Biome: a biome is a large area of the erath’s surface. Which has a particular climatic factor and characteristic flora (plants) and fauna (animals), examples include savanna grasslands.

5. Ecosystem: is a natural unit composed of both biotic (living) and abiotic (non-living) factors, which interacts with each other to for a stable self-sustaining system. For examples include pund , lake, forest and sea shore. Community: is a group of organisms belonging to different species living in the same area. For example in a pond the community includes the fish, insects, protozoa and aquatic plants.

6. Components of the environment There area two components of environment namely abiotic components of environment and biotic components of environment

7. Abiotic components of environment These are the non-living factors. They are also known as physical factors. These factors are grouped into three categories for easy study namely climatic factors, topographic factors and edaphic factors. Climatic Factors These are the factors which are associated with the prevailing climatic conditions where, the living organisms is found. These include light, temperature, wind, humidity, rainfall and atmospheric pressure

8. Light The main source of light is the sun. Light is the form of energy that is used by different living organisms, notably light is used by plants during photosynthesis. Where light is captured by chlorophyll to complete the process. Light intensity is measured using Photographic light meter. Light penetration in water is measured using seechi disc

9. Temperature Temperature is a physical quantity that expresses quantitatively the perceptions of hotness and coldness. Temperature effects the distribution of organisms and determines the activities of animals. Temperature affects biochemical activities such as the working enzymes. There are few animals that can tolerate high temperature some animals can regulate their body temperature and hence have wider distribution. Such animals are called homoiotherms . They include birds and mammals. Some animals conform to the extreme temperatures and hence have limited distribution. Such animals are called poikilotherms . They include reptile and amphibians. Temperature is measures by using a thermometer .

10. Maximum and minimum thermometer

11. Wind Wind is the moving air. Air can modify the temperature and humidity of air surrounding organisms. Wind speed is measured by using anemometer. Wind direction is determined by Wind Vane and wind strength is measured using Wind stock

12. Humidity Humidity is the amount of water vapor in the atmosphere. Relative humidity is the amount of water vapour air can hold at given temperature. Humidity affects the rate of respiration and evaporation. Humidity is measured by using Hygrometer

13. Rainfall (precipitation) Rainfall is the main source of the soil water used by terrestrial plants and animals. Water is also a raw material for the photosynthesis process. Rain is measured by using rain gauge

14. Atmospheric Pressure This is the pressure exerted by the atmosphere upon the earth. It varies with altitude. Atmospheric pressure affects the amount of the respirator gases that is, oxygen and carbon dioxide. Atmospheric pressure is measured by using barometer