Environmental Studies PDF

ENVIRONMENTAL STUDIES COMPILED BY MS. M. MASHEGO FOR CURRO KRUGERSDORP BIOSPHERE The biosphere refers to all living organisms on Earth The biosphere is the part of the Earth where humans and other organisms are able to live. Characteristics of the biosphere The biosphere con...

ENVIRONMENTAL STUDIES COMPILED BY MS. M. MASHEGO FOR CURRO KRUGERSDORP BIOSPHERE The biosphere refers to all living organisms on Earth The biosphere is the part of the Earth where humans and other organisms are able to live. Characteristics of the biosphere The biosphere consists of the atmosphere, the hydrosphere and the lithosphere.  THE ATMOSPHERE 1. is made up of gases that keep the environment stable 2. has the gases oxygen, hydrogen, carbon dioxide, water vapour and nitrogen 3. is involved in breathing and cellular respiration, photosynthesis and protection against harmful ultraviolet sun rays.  THE HYDROSPHERE 1. is the aquatic or water part of the biosphere 2. consists of the waters of the oceans (salt water), rivers and lakes (fresh water) 3. is the habitat of many aquatic organisms such as fish.  THE LITHOSPHERE/GEOSPHERE 1. is the outside crust of the Earth 2. is formed of rocks and soil 3. is a source of some of the mineral ions which living organisms need.  Studying the biosphere Biosphere – where life is found on Earth, made up of the atmosphere (air), hydrosphere (water) and the lithosphere (land). Biome – a large area with a certain climate and certain species of plants and animals. A biome is made up of smaller areas called ecosystems Niche – the role an organism or species plays where it lives. Habitat – a place where an organism lives. Organism – a single organism. SPECIES a group of organisms of the same kind, which can breed with one another and produce fertile offspring.  POPULATION a group of organisms of the same species, living in a specific area at the same time.  COMMUNITY a biological community is all the populations of all the different species in a particular place; for example, populations of lions, impala, birds, warthogs, thorn trees and other plants that interact in an area. ECOSYSTE M different communities of plants and animals interacting with each other and with their physical (non-living) environment. CLASSWORK 13 SEPT 2024 QUESTION 1 1. Fill in the missing words: 1.1. The biosphere is a group of spheres (or layers) where life exists on Earth. (1) 1.2. The biosphere contains living organisms. When these organisms die, they become dead organic matter. (1) 1.3. The biosphere is made up of the atmosphere, the hydrosphere and the lithosphere. (2) QUESTION 2 2. Select the correct answer from the options given. Indicate your answer by encircling the letter next to the statement of your choice. 2.1. The lithosphere is made up of: A all the water on the earth B a layer of gases C soil and rocks D clouds 2.2. The following living things are not found in the hydrosphere: A algae B seaweed C fish D seagulls QUESTION 2 AND 3 2.3. Animals that spend their time in the earth’s atmosphere include: A birds and dolphins B birds and bees C spiders and eagles D. birds and sharks 3. Identify the three kinds of living things that are found in the biosphere. (3) QUESTION 4 4. Indicate whether the statements are true or false: 3.1. Micro-organisms are living things that can be observed with the naked eye. 3.2. Aquatic means “living in water”. 3.3. Dead vegetation does not form part of the biosphere. QUESTION 5 Select any 2 spheres in the biosphere (there are 3 in total). Next to each one write the names of 4 living things found in that sphere. (8)  Biomes – aquatic and terrestrial The biosphere is divided into many biomes. Biomes can be divided into aquatic (water) and terrestrial (land) types. Aquatic biomes are divided into 1. marine (saltwater) and 2. freshwater types. A biome: contains specific kinds of plant and animal life that are adapted to the environment is made up of several ecosystems.  Marine biomes of South Africa South Africa has a long coastline. It has the following features: The east coast where the warm Agulhas Current influences the water temperature. The west coast where the cold Benguela Current influences nutrient content. The south-western and south coast, where these water masses mix. The ocean tides, currents, temperature changes and oxygen and salt content have an effect on the kinds of animal and plant communities that are found along the coastline.  Marine biomes of South Africa Thick marine forests of giant kelp and sea bamboo are a major source of food and also give shelter to fish, other marine animals and plants. The east coast waters have a greater biotic diversity of plant and animal species than the south-west and south coast waters. Marine biomes: sandy beaches, rocky shores, coral reefs, benthic beds (the ocean floor) and the pelagic zone (open, deep ocean). Sandy beaches Sandy beaches have: a moving layer of sand dunes continual wave and current action an inter-tidal zone where the ocean meets the land cyclical daily wet and dry periods as waves and tides come in and out. Rocky shores Rocky shores are found in many places along our coastline. They provide a firm, strong foundation for plants and animals to attach to. They are the habitat of a great diversity of marine organisms. Coral reefs Coral reefs are found in the warm subtropical waters off the coast of northern KwaZulu-Natal. They are home to many fish species and other marine animals. Along with tropical forests, they support the biggest diversity of organisms on the Earth. The open sea The deep sea has no firm base. Organisms found are fish, phytoplankton and zooplankton. Fish of different sizes, whales and dolphins swim in the open sea. Phytoplankton are microscopic plant-like organisms, such as algae, that can photosynthesise. Zooplankton are animal-like organisms – some are just visible with the naked eye but most are microscopic. Estuaries Estuaries are the meeting places of the rivers and the sea – where fresh water meets salt water. They have features of both marine and freshwater biomes. Organisms are specially adapted to tolerate salt and fresh water. The fresh water brings rich nutrients from the land. Mixing of salt and fresh water allows huge numbers of marine life to exist. Freshwater biomes Freshwater biomes are rivers, streams, ponds, lakes and wetlands. These biomes are affected by changes in climate and weather. Wetlands Wetlands are areas with waterlogged soils, or areas covered with a shallow layer of water. They may be permanently or seasonally covered with water. They are important because they: -are flood controllers because they slow down flood water -are filters that improve water quality by trapping sediments -hold nutrients such as phosphorus and nitrogen, and even harmful bacteria -are wildlife habitats – they provide food and shelter for many animals. Wetlands