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47 Cards in this Set
- Front
- Back
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Whats nutrient cycling |
When dead material is decomposed, nutrients are released into the soil. The nutrients are then taken up from the soil by plants. The plants may be eaten by consumers. When the plants or consumers die, the nutrients are returned to the soil |
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What is an ecosystem |
A unit that included all biotic and abiotic parts in an area |
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Grassland |
There are two types of grasslands. Savanah and temperate. Savannah are found between the tropics , distinct dry and wet seasons, rainfall is still relatively low. Vegetation is mainly grasses with a few scattered leaves. Temperate grasslands are found at higher latitudes where there is more variation in temperature and less rainfall. No trees here , just grasses |
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Tundra |
Found at higher lattitudes (above 60°N) in northern Europe , Alaska and northern Canada. winters are very cold, summers are brief and there is little rainfall. There are hardly any trees , vegetation includes mosses, grasses and low shrubs. There's a layer of permanently frozen ground called permafrost. |
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Temperate deciduous Forrest |
Found mainly in the mid lattitudes where there are four distinct seasons. Summers are warm, winters are relatively mild and there's rainfall all year round. Deciduous trees lose their leaves in winter to cope with colder weather. |
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Tropical rainforrests |
Found around the equator , between the tropics where it's hot and wet all year round. This is an area of lush Forrest , with dense cannopies of vegetation forming distinct layers. |
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Polar |
Found around the north and south poles. They are very cold, icy and dry. Not much grows at all. They remain dark for several months each year so the growing season is very short , about 2 months. |
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Hot desert |
Found between 15° and 35° north and south of the equator where there's little rainfall. It's very hot during the day and cold at night . Shrubs and cacti are sparsely distributed in the sandy soil. |
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In depth description of tropical rainforrests |
Climate is the same all year round. Hot, temperature is about 20 - 28°c . It is near the equator so sun is overhead making it always hot . Very high rainfall, around 2000mm per. Rains every day mainly in the afternoon. Thin layer of nutrients, decay is fast due to warm moist conditions. Soil isn't very fertile as rain washed them away. Most trees are evergreen(don't drop the leaves) to take advantage of the continual growing season. Many trees are really tall and the vegetation cover is dense- very little light reached the Forrest floor. Lots of epiphytes (plants that grow on other living plants and take nutrients and moisture from.the air ). Contain loads of animal species. Many animals are brightly coloured and make a lot of noise Home to many people who have adapted to life. Live by hunting and fishing , and growing vegetables in small garden plots. |
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What are symbiotic relationships |
When plant and animal species Depend on each other to survive, e.g. if one decreases the other decreases. |
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How do plants adapt to living in rainforests |
Tall Trees compete for sunlight , they have big roots called buttress roots to support trunks. Plants have thick waxy leaves with pointed tips (drip tips). Drip tips channel the water so it runs of, so weight of the water doesn't damage plant, and there's no standing water for fungi and bacteria to grow in. Waxy coating of the leaves helps repel the rain. Trees have smooth thin bark , no need to protect from cold temps. Allows water to run of easily. Rainforests have four distinct layers of plants with distinct adaptations ( top is emergents, then canopy, undercanopy, then shrub later at bottom) Plants drop their leaves gradually throughout the year , meaning they can go on growing all year round |
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How are animals adapted so they can find food and escape predators |
Many animals spend their whole lives in the canopy. They have strong limbs so they can spend all day climbing and leaping from tree to tree. Some animals have flaps of skin enabling them to glide between trees. Some have suption cups for climbing, like frogs Some birds have short, pointy wings so can move easily between dense tangles of branches in the trees Some animals are camouflaged so they can hide from predators Many animals are nocturnal. sleep at day and feed in night, saving them energy Some animals are adapted to low light levels of the rainforest floor Mainly animals can swim allowing them to cross River chanells |
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Why does deforestation happen |
As population increases trees are cleared to make land for new settlements Mineral extraction , minerals are mined and sold to make money Energy development, building dams to generate hydro electric power Commercial logging - trees are felled to make money. Road building for logging also requires more tree clearence Commercial farming - Forrest is cleared to make space for cattle grazing or for huge palm oil or soya plantations. Farmers clear forest so they can grow food for themselves and their family . |
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Environmental impacts of deforestation |
No trees to hold soil together, rain can wash away the soil (soil erosion). This can lead to landslides and flooding. Without a tree canopy water isn't intercepted and no tree roots so no absorbed water . More water reaches the soil. This reduces soil fertility as nutrients in the soil are washed away. More CO2 |
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Economic impacts of deforestation |
Logging, farming and mining create jobs. Money is made from selling timber,mining and commercial farming . Long term, resources the country depends on are destroyed , like timber, and reduced attractiveness for tourists Loss of plants and animals that people rely on to make a living. |
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Deforestation case study |
The Amazon rainforest is the largest rainforrest on earth , covers an area of approx 8 million km^2 Since 1978 over 750,000 has been destroyed by deforestation Between 2000 and 2005: 65-70% caused cattle ranching (raising cattle) 20 -25% caused by small scale subsistence farming 5-10% caused by other commercial farming- mostly soy farming, but rice, corn and sugar cane are also grown. 2-3% was caused by logging, illegal aswell. Roads have opened up areas of the forrest that were previously too hard to get to. 1-2% caused by other activities such as mineral extraction (e.g. gold mining), road building , energy development and building new settlements. Migration to the area puts pressure on the Amazon rainforest. Brazilian government offers lands to poor people in the rainforrest Environmental impacts 100 billion tones of carbon stored in trees , deforestation will release some of this 55 million tons of topsoil lost every year due to soil erosion by soy farming Economic Development brought wealth to poor countries Farming brought loads of money , in 2008 Brazil made $6.9 billion from trading cattle. Second biggest exporter of soya beans. Logging contributes huge amount to Brazil's economy.
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Why should tropical rainforests be protected |
To preserve its biodiversity of plants and animals, they have value to the environment and people Many products are sourced from the rainforrest like rubber, medicines,coffee and chocolate. Development through ecotourism. Reduction of greenhouse effect Rainforrests help regulate the climate and water cycle |
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Selective logging |
Certain trees are felled. Like older ones. Less damaging to the Forrest. Overall forest structure is kept , canopy still there and soil isn't exposed. Forrest can be used in the future. Least damaging forms are horse logging and helicopter logging. Dragging felled trees out using horses or helicopters. This way your not using huge trucks. |
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Replanting |
New trees planted to replace the ones that are cut down.Trees for people in future replace the ones that are cut down.Trees for people in future . the ones that are cut down.Trees for people in future Trees for people in future Trees for people in future |
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Replanting |
New trees are replanted to replace the ones cut down. Will be trees for use in the futre. Important for the same type of tree that was cut down to be planted , so variety of trees is kept in the futre. Countries have laws were logging companies must replant trees. |
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Ecotourism |
Small number of people allowed in certain areas Income.for people, they act as guides and provide accommodation and transport. These people employed don't have to log as they have a job, fewer trees are then cut down. |
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Ecotourism |
Tourism that minimises damage to enironment and benefits people . Small.number of visitors in an area People.employed so money
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International Hardwood agreement |
Hardwood is specific type of wood. International agreements to reduce illegal logging and promote hardwood from sustainably managed forests. wood is marked with logos to show it's been sustainably sourced. |
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Education (deforestation) |
Educating people on impacts of deforestation and encouraging people to buy products that are from.sustainably.managed sources
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Reducing debt |
Countries in debt often allow logging farming mining etc to pay back debts. Debts can be reduced in order to stop this . No certainity if they will act. Better to reduce debts in order for money to be spent on conservations |
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Conservation |
National parks in rainforests have damaging activities restricted. money can be donated to enforce restrictions on damaging.activities |
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Climate of hot deserts |
Less then 250mmm of rainfall per year Approx 45°c in the day to 5°c In the night |
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Soil in deserts |
Shallow with a coarse, gravelly texture. Hardly any leaf fall so not very fertile. This and a lack of rainfall makes it dry |
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People in deserts |
Grow few crops were there is water, like at desert fringes |
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What is irrigation |
Artificially watering the land to grow crops. This water is taken unsustainablely from the groubds, animals and plants depend on this water. |
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Cattles overgrazing |
Causes soil erosion. Without plant roots to stabilise the soil, wind blows soil away. This makes clouds of soil which reduces rainfall. |
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Plant roots in desert |
Extremely long to reach water ,or spread out very wide near surface to catch as much water as possible |
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Succulents(plants) |
Large fleshy stems to store water and thick waxy skin to reduce water loss . Some have Sharp spines and toxins to stop animals stealing water from stems |
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Nocturnal animals |
Can stay cool in burrows during the day or sit still in the shade while it's hottest. Often have limbs or ears, providing larger sa to lose heat |
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Some animals store fat |
Which they can break down into water |
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Most deser animals minimise |
Water loss from swear and urine |
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Animals cope with sand |
Camels have tripple eye lids , long eye lashes and can close nostrils . Have large,flat feet so they don't drink into the sand . |
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Development in hot desert case study |
Thaar desert, located in India, jaisalmeer. One of the hottest deserts with the highest population density. Minerals found in the desert are gypsum, which is used to make plaster and phosphate used to make fertiliser Large oil fields, largest windfarm in a desert Majority of people who live in deserts survive of farming and grazing animals Tens of thousands visit jaisalmeer each year Challenges Temperature can exceed 50°c in the summer. This leads to high rates of evaporation and water shortages Low amounts of rainfall and high levels of evaporation and high demand for water for farming and growing population Cars can break down.due to heat
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Desertification = |
The degradation of land so it becomes more desert like , drier and less productive. |
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Soil erosion |
Soil that is exposed (not covered by plants ) easily removed by wind or water. Nutrients in the soil are lost making soil unproductive. |
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What are the two main causes of desertification |
Climate change and human activities |
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Climate change and desertification |
Rainfall is reduced ..less rain means plants die. Plant roots hold soil together, so now soil is more easily eroded. Temperature increase , more water evaporates, soils drier and plants die, then soil erosion occurs |
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Desertification by human activities |
People rely on wood for fuel for cooking. Trees being removed mean soil is exposed and easily eroded. Overgrazing -too many cattle eat plants faster then they can regrow. Plants no longer hold soil together If crops are planted in same area continuously all the nutrients in the soil get used up. Soil erosion increases without plants Population growth increases all this |
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Water management |
Growing crops that don't need much water , reduce water usem |
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Tree planting |
They protect soil from wind erosion. They also provide shade which reduces temps and evaporation rates |
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Soil management |
Letting areas of land to rest between grazing or planting . |
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Technology |
Using solar cookers , use suns hear Sans fences stabilise soil and reduce erosion. |
