In this section learners will focus on summarising the importance of terrestrial and aquatic biomes of Southern Africa. They will study how climate, soil and vegetation influence the organisms found in each. The location of the different biomes in South Africa will also be introduced. The biosphere is divided up into a number of biomes. Biomes are regions with similar climate and geography. The key factors determining climate are average annual precipitation (rainfall) and temperature. These factors, in turn, depend on the geography of the region, such as the latitude and altitude of the region, and mountainous barriers. The specific conditions of biomes determine the plant and animal life found within them. The communities of plants, animals and soil organisms in a particular biome are collectively referred to as an ecosystem. Biomes can be aquatic or terrestrial. Water covers a major portion of the Earth's surface, so aquatic biomes contain a rich diversity of plants and animals. Aquatic biomes are divided into two main groups depending on the amount of salt present in the water: freshwater and marine biomes. 1. Freshwater Freshwater biomes are defined by their low salt concentration, which is usually less than \(\text{1}\%\). Examples include: ponds, lakes, streams, rivers and wetlands. 2. Marine biomes Marine bodies are salty, having approximately 35 grams of dissolved salt per litre of water (\(\text{3,5}\%\)). Marine biomes are divided into oceans, coral reefs and estuaries. The vegetation of the marine biomes consists of the different types of algae, which is one of the major sources of oxygen in the world. Green algae also play a role in the removal of carbon dioxide from the atmosphere.
Figure 8.2: Ocean ecosystem.
Figure 8.3: Coral reef.
Figure 8.4: Knysna Estuary. Marine biomes of South Africa South Africa's long coastline stretches for over 3000 kilometres, from Namibia in the West to Mozambique in the East. There are a few key features to note about South Africa's coastline and marine biomes. South Africa's coastline is rugged, as rocky shores are exposed to high wave energy and the coastline generally experiences high wind for most of the year. There are up to 343 estuaries found along the coast, two thirds of which are found on East Coast between Cape Padrone in the Eastern Cape Province and Mtunzini in KwaZulu-Natal. The Eastern coastline receives the highest rainfall, mostly during summer. South Africa's East Coast has relatively warm waters (20-25 degrees C), the West Coast receives colder Atlantic waters (9-14 degrees C), and the South Coast experiences intermediate water temperatures (16-21 degrees C). The cold Benguela Upwelling System on the South-West coast supports large numbers of marine animals. The warm Agulhas current off the East Coast has a smaller quantity of fish but a greater diversity of species. Abundant opportunities exist for tourism, recreation, food, export and associated economic development. Terrestrial biomes occur on land and can be of many types. Examples include: thicket, tundra, forest, grassland and desert. Terrestrial biomes are usually classified based on the dominant vegetation, climate or geographic location. The location and characteristics of the various biomes is mostly influenced by climatic conditions such as rainfall and temperature. The most recent classification of the terrestrial biomes in South Africa divides the region into the following eight biomes:
The biome regions in South Africa are mapped in Figure 8.5. Figure 8.5: Biomes of South Africa. 1. Grassland Biome
Figure 8.6: Grasslands are regions where the vegetation is dominated by grasses. Figure 8.7: Grasslands are regions where the vegetation is dominated by grasses. Compare and analyse the advantages and disadvantages of burning grassland.
Activity: Burning of grassland Answers Below are a couple of advantages and disadvantages related to the burning of grassland. However, learners may also come up with different examples, and as long as they can cite their source, their answers should be accepted.
2. Savannah biome
Figure 8.8: Savannah biome. Figure 8.9: Savannah biome. 3. Succulent Karoo biome
The word 'Karoo' comes from the Khoi word Karusa, which means dry, barren, thirstland. Karoo is an apt description for this arid region. 4. Nama Karoo
Figure 8.10: Nama Karoo found in the Northern Cape province. 5. Forest Biome
Trees are not only producers, but as a result of their size they also create a habitat for other species. The leaf cover of trees provides shelter for animals, while the bark and fissures in the trees also provide a habitat for insects. The leaf cover also creates a shady environment in which shade-loving, low-growing plants can flourish.
Figure 8.11: Forest biome. Figure 8.12: Knysna Forest.
When leaves or fruit fall from the trees and collect at the feet of the trees, another series of organisms can appear. By breaking down organic material, decomposers such as microorganisms return the organic nutrients to the soil. Humus is formed in this way. Humus is dead organic material. Other creatures that live off decayed organic material, namely the detritivores, also promote this process of decomposition by breaking up dead plant matter into its component nutrients.
Project: Create a poster to illustrate the key role-players in a Forest Ecosystem The answers to the questions will depend on the poster the learners have done. Each poster should have different answers to the questions. Questions
Answers
The Fynbos contains approximately \(\text{75}\%\) of South Africa's rare and threatened plants. 6. Fynbos
Figure 8.13: Mountain Fynbos found in Western Cape. The flora of the fynbos has a high degree of endemism. This is the ecological state of being specific to a geographic location such as an island, country or in this case, a defined biome such as the fynbos. Fire is a necessary stage in the life-cycle of nearly all fynbos plants, and is common during the dry summer months. Many of the seeds germinate only after the intense heat of a fire. As proteas 'prepare' for the fire, they retain their seeds on the bush for at least a year, a habit known as serotiny. Figure 8.14: Fynbos in Cape Peninsula.The lowlands of the fynbos have been developed for agriculture and wine farming. Due to this, various species of fynbos have been threatened. For this reason, the fynbos region must be protected and preserved. It is a major tourist destination. The astonishing richness and diversity of the Western Cape's natural resources is matched only by the resourcefulness and diversity of its many people. Historical patterns of unsustainable use of resources have led to the Cape Floristic Region (CFR) being listed as one of the world's threatened bioregions, and the scars are deeply etched in the land and its people. Western Cape residents are exploring new and sustainable ways to value and benefit from these globally important assets. South Africa's Cape Floristic region is legendary, and the unique nature of the fynbos biome has been celebrated by biologists, conservationists, development experts, and ecologist worldwide. (Adapted from speech by Tasneem Essop the Western Cape Provincial Minister for Environment, Planning and Economic Development) Write an essay on the fynbos biome and discuss the following aspects:
Your essay may be written or typed. Marks will be awarded for originality and own interpretation. Include a bibliography of three of more resources. No marks will be awarded for plagiarism. Project: Learners to write an essay on the fynbos using the source information provided Write an essay on the 'Fynbos' biome and discuss the following aspects.
Essay may be written or typed. Marks will be awarded for originality and own interpretation. Include a bibliography of three of more resources. The exact content of such an essay cannot be specified and is up to the individual teacher. The following may serve as a guideline only: Fynbos Biome Definition Fynbos is the natural shrubland or heathland vegetation occurring in a small belt of the Western Cape of South Africa, in coastal and mountainous areas with a Mediterranean climate. The soil is acidic and nutrient-poor, while the climate is marked by cold wet winters and hot dry summers. It is the smallest of the world's six floral kingdoms. Indicator Species Small, fine-leafed, low-growing and tough evergreen plants. Fynbos includes legumes and bulbous plants (like Watsonia spp. and chincherinchees), but the three main indicator groups are Ericas, Restios and Proteas .
Ecological role This biome can’t support large animals due to lack of enough nitrogen, but the area has many smaller animals like baboons, klipspringers, grysbok, dassies, mongooses and mice. Many endemic sunbirds are found here, also highly endangered butterfly species, like those whose larvae actually eat ants and live inside the ant colonies. The geometric tortoise, the world’s second rarest tortoise, is found only here, as well as several endangered frog species. Biological impact of destruction Again, possible answers vary widely. They should mention the loss of biodiversity, the threat to our natural heritage, possible cures for disease in plants that have not yet been studied scientifically, the loss of ecotourism and the jobs / income associated with this, the fact that extinction is forever and cannot be reversed, etc. Economic impacts of this area for people
Management strategy and Protection
Below is a list of other miscellaneous facts that students may choose to include in their essays:
No marks should be awarded for plagiarism. 7. Thicket
8. Desert Biome
Figure 8.15: Kalahari desert.
Did you know that most of the animals in the desert can live without water for a long time? They have adapted in many ways to do this. For instance, they can store water internally, take water out of their prey, or peck at succulents and suck out the water stored inside them. Getting to know the biomes of South Africa.
Study some advertisements for ideas. You work for an Advertising Agency that is bidding for the account of a top travel agency. The bid includes designing a full page advert (A4) for the Getaway Magazine. Presentation, appeal and accuracy will therefore be of top priority. The travel agency has specified that they would like the following to be included in the ad, which is geared towards people looking for a different and fascinating holiday in a specific biome:
Biomes Advertisement This is an optional activity that teachers may include if they want to. Assessment will be based on the fulfilment of the criteria given and may require the assistance of a member of the Language and /or Art department of the school, to ensure that the adverts are assessed for scientific accuracy, as well as artistic appeal and visual impact. It is recommended that a rubric be drawn up to guide assessment, such as the example given below. The teacher just ticks the relevant box and allocates the mark above that column: Rubric to asses the biome poster
Total out of 25 marks: The following activity is to be done in groups of four Instructions
Biome Project It is suggested that a rubric similar to the above be drawn up for assessment of the project. Such rubrics go a long way in standardising the assessment for different projects and they ensure that learners are given adequate feedback about what was correct / wrong about their project. All teachers who have learners in this grade should come together and have a brainstorming session themselves, deciding on what the criteria are they will assess and what aspects will be taken into account within each criterion. The more clearly the criteria and sub-topics are defined in the beginning, the better. This cannot be over-emphasised. It should be made clear to learners that group work DOES NOT involve one or two members doing all the work and others sitting back as spectators. ALL of them have to get involved and make a contribution to the project. The teacher may ask that they allocate specific tasks, e.g.
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