Ecosystems Flashcards
(118 cards)
1
Q
Definition of an Ecosystem?
A
A system in which organisms react with eachother and their environment
2
Q
Definition of ecology?
A
The study of communities of living organisms and their relationship to their living environment
3
Q
Definition of biomes?
A
Large areas cutting across continents yet each with their own characteristics
4
Q
What are zones?
A
Units within biomes
5
Q
What are Habitats?
A
More specific conditions with an adapted community
6
Q
What is biomass?
A
The total weight of all organisms including dead plant matter
7
Q
What is the aim of conservation areas?
A
To protect and restore natural ecosystems. By protecting species and their habitats to support the biodiversity.
8
Q
What are other reasons for developing ecological conservation areas?
A
Improves appearance of an area- e.g. Brownfield sites
Stimulating investment to encourage multiplier effect- e.g. Tourism
Managing flood risk- e.g.- afforestation
9
Q
How do we afford conservation areas?
A
Limited budget
Rely on volunteers
10
Q
What is the governmental principal advisor on the natural environment?
A
Natural England
11
Q
3 examples of conservation areas?
A
SSSI- Natural England
National nature reserves- National trust and RSPB
Local Nature reserve
12
Q
How is Sheffield blue loop funded?
A
By Natural England and the National lottery
13
Q
How is the blue loop managed?
A
By a partnership of Groundwork Sheffield and the River Stewardship company
14
Q
What is the aim of the blue loop?
A
The support and engage local communities along the waterside environment
15
Q
History of Blue loop Sheffield?
A
The river don was used for industry but was difficult to navigate.
The opening of the Sheffield and Tinsley canal in 1819 provided the infrastructure for mass export of coal and steel.
In 1848 railway was introduced.
Decline of canal and associated industries.
16
Q
Native species to blue loop?
A
Fish- fish ladders have been built to allow upstream movement
Otters- secluded nesting and breeding habitats provided
Butterflies- nettles along the canal provide perfect habitat
17
Q
Benefits of the scheme?
A
Encouraged tourism and private investment
Reduced flood risk
Provides recreational activity
18
Q
Where is the tropical equatorial rainforest located?
A
Within the tropics, between the Tropic of Capricorn and Tropic of Cancer
Lies within 5 degrees of the equator
19
Q
Figures on tropical biome?
A
Rainforest covers less than 5% of the earths surface. It halved in 200 years. Support 50% of all living organisms
20
Q
Temperature characteristic of the rainforest?
A
A low diurnal temperature range. Day 28 night 22
21
Q
Rainfall in the rainforest?
A
Daily conventional storms
2M of rain each year
Violent storms occur in afternoon following intense heat
22
Q
Other characteristics of the rainforest?
A
A year round growing season- average day 12 hours of sunlight
High humidity- rapid evapotranspiration
23
Q
Number of species and trees found in the rainforest?
A
50 million species of animal
480 tree species per hectare
24
Q
What is the stratification of the rainforest?
A
Emergent layer- 30-40m Canopy- 20-30m Understory- 10-20m Shrub layer Forest floor
25
Describe the soil in a rainforest?
Rapid chemical weathering of bedrock
Soils are fragile and depend on leaf fall for nutrients
The rapid decomposition of litter and work of biota results in a thin humus layer
26
What are the main causes of deforestation in the Amazon?
Farming- eg Cattle ranching, Cash crops plantations e.g. palm oil and soya (used to feed chickens in U.K. Fast food chains)
Mining- Amazon is the largest source of iron ore
Logging- timber production
27
Further causes of Amazon deforestation?
Road construction- The Trans- Amazonian Highway extends 6000km into Brazil's interior
Settlement growth- migration from poorest parts of Brazil
28
Environmental impacts of Amazonian deforestation?
Shifting cultivation not successfully carried out, plots lost fertility and yields decline. Knock on effect to natural cycles and species diversity.
Mononcultures demand high amounts of fertilisers and pecticides. Leaching enters water killing fish
29
Positive economic impacts of Amazonian deforestation?
HEP Project delivers power for mining. Minining employs over 7000 workers
30
Who came up with the process of nutrient cycling?
Gersmehl
31
How do the nutrient cycling diagrams work?
The thicker the arrow the larger the flow.
32
Difference between nutrient cycle in rainforest and woodland.
Soil is larger in woodland
Higher precipitation input in rainforest therefore higher runoff
Larger litter in woodland
Weathering input higher in rainforest
33
Inputs into nutrient cycling?
Precipitation
| Weathering
34
Outputs in nutrient cycling?
Run off
| Leaching
35
Processes in nutrient cycling?
Leaf fall
Litter decomposition
Plant nutrient uptake
36
Stores in nutrient cycling?
Biomass
Litter
Soil
37
Trophic levels?
Autotrophs
Primary consumers
Secondary consumers
Tertiary consumers
38
Function of reducer organisms?
Return remaining nutrients back to the soil for plant growth
39
How much energy is lost at each trophic level?
90%
40
How are energy losses illustrated?
Energy pyramids
41
What is urban wasteland?
Abandoned land that has been left for nature to take its course
42
Examples of urban wasteland?
Brownfield sites- former factories, route ways and railways
43
First step in wasteland succession?
Pioneer species colonise bare surfaces, death of these adds humus and moisture to the layer
44
Second step in wasteland succession?
Seed plants grow in sheltered cracks with moisture available
45
Final step of wasteland succession?
Tall herbs outcompete smaller species where nutrients are.
| Taller grass and bushes thrive in deeper soils
46
Positive non-native species?
Tomato and corn
47
Figure on Japanese knotweed?
Has doubles its coverage in the last 20 years. Mostly present along Londons waterways
48
How can Japanese knotweed be killed?
Strong herbicides and burning roots
49
What is the soil profile of the tropical equatorial rainforest?
Iron and aluminium build up gives the soil a dark red colour
Clays produced further down
Some redeposited silica gives a yellowish colour
Weathered bed rock and parent material
50
Why is leaching high in the tropical rainforest?
Heavy rainfall
51
Statistic on Japan and need for logging?
Japan is solely responsible for using 11 million cubic metres of equatorial hardwood each year
52
Example of mining in the Amazon?
Carajus in Amazonia is home to the largest source of iron ore
53
What are other reasons for deforestation?
Road construction- Trans Amazonian highway
Hydro-electric power
Settlement growth
54
Statistics about Brazil's people?
Over 25 million landless people
55
Background to deforestation?
1950's- beginning of mechanised logging and development of integrated transport and infrastructure has caused the deforestation rates to soar
56
Environmental impacts of deforestation?
Approx 20,000 tropical equatorial rainforest species become extinct each year.
Increased flooding- change in rainfall patterns
57
What roles do tropical equatorial rainforests play in the carbon cyle?
A tropical equatorial tree is a carbon sink for 22.5kg of carbon dioxide each year.
Burning the rainforest accounts for 20% of the global atmospheric carbon dioxide each year
58
Economics impact of deforestation?
Workers exploited by corrupt government or TNC powerhouses. The economic benefit rarely trickles down.
The world bank has supported plans to expand timber production in Congo and Indonesia
59
Social impacts of deforestation?
The Quichua Indians of Tina, in Ecuador. Native people who inhabit rainforest. Deforestation destroys their social cohesion, language, culture and tradition.
60
Government corruption in Brazil?
Brazilian government offers rainforest land to those better off financially- sidelining smaller settlers
By offering subsidies to large commercial operations.
61
What export is Brazil a world leader in?
TNC's frequently from USA have made Brazil a world leader in beef and soya exports
62
Social tensions in the Amazon?
Miners try to illegally steal land from native Indians.
The traditional Yanomami and Yekuana tribes oppose mining.
New settlers bring diseases- Panara Indians have all but been wiped out
63
What is an example of an agribusiness?
Cargill
| A large US transnational food, agricultural, financial and industrial agribusiness
64
Background figures on Cargill?
Employs 138,000 people in 67 countries
| In 2009 recorded net profit of over $3.3 billion.
65
Cargills commitments?
We will develop ways of reducing environmental impacts and help conserve natural resources
We will invest in communities where we work
66
How is Cargill environmentally unsustainable?
Arrived in Brazil in 1965
| Between 2002 and 2004 annual deforestation rates have jumped from 15,000 to 28,000 hectares where Cargill operates
67
Area where Cargill operates?
Santarém
68
What is the predominant use for soya?
97% for animal feed
69
Fact in Brazil and U.K.?
78% of UK soya beans are from Brazil
70
Example of unsustainable tourism?
In 1992- The Bwindi Impenetrable Forest was upgraded to a national park. The indigenous Batwa Pygmies were removed.
71
When are non-native species bad?
When they compete with native plants, have no predators
72
Niches along routways?
Restricted access- railways
Air pollution
Halophytes from salt spreading
Afforestation
73
Examples of adapted plant communities?
Xerophytes
| Hydrophytes
74
What is vegetation succession?
How plant communities evolve and develop over time
75
What is each stage in succession called?
A sere
76
What occurs if succession occurs without being disturbed?
Vegetarian climax
| Vegetation is in equilibrium with the environment
77
Definition of Climatic climax?
The final stage of natural succession where vegetation is in equilibrium with the climatic and environmental conditions.
78
What are the 2 types of succession?
Primary and secondary
79
Describe primary succession?
On surfaces which haven't had previous vegetation growing their. E.g.- bare rock after a volcanic eruption
80
Describe secondary succession?
On surfaces which have been colonised by vegetation previously, but have since been changed or destroyed.
E.g.- deforestation
81
How do the pioneer species induce growth of the next sere?
Hardier plants die and decompose by bacteria
| Weathering breaks down rock and adds to humus
82
What does each seral stage have?
Increase in height of plants and no. Of species
83
Hydrosere step 1.
Spores of algae and mosses blow onto water surface creating a pioneer community of floating vegetation
84
Hydrosere step 2.
Floating and submerged water weeds (lillies) can then develop
85
Hydrosere step 3
These weeds trap sediment at the waters edge to allow marsh plants such as reeds and rushes to establish
86
Hydrosere step 4
Continuing sedimentation of silt and plant debris slowly builds which will eventually rise above water
87
What is a Carr?
A low lying area of land emerging from a fresh water pond or lake
88
Hydrosere step 5
This will produce a Carr of small shrubs and trees such as willow and alder
89
Hydrosere step 6
Finally the climatic climax of oak and ash trees can emerge. Dominating the whole site once the pond silts up entirely
90
Features of the temperate deciduous woodland biome?
Dominant oak trees- ave 20m
Leaves have large crowns
Thick leaf litter
Brown earth soil
91
Stratification in deciduous woodland?
Oak, ash and chestnut trees
Rowan, holly and hazel- shrub layer
Brambles, bracken and flowering plants e.g.- bluebells - field layer
Mosses and lichens- ground layer
92
Describe brown earth soil?
Deep, well drained, fertile, and support and large amount of fauna
93
Example of deciduous woodland?
Hayley wood in Cambridgeshire
94
Why is brown earth soil ideal for growth?
Decomposes break down leaf litter to rich, dark brown humus
Slightly acidic
Earthworms and rodents mix the layers to aerate the soil- prevent leaching and water logging
95
What is a plagioclimax
When succession is disturbed by human intervention, preventing climatic climax
96
Where are the heather moorlands?
North Yorkshire
97
History of Heather Moorlands?
Three thousand years ago was the climatic climax.
Woodland cleared for farming and soils deteriorated.
The efficient nutrient cycle was distorted and ground was exposed to heavy rainfall.
98
What happened after woodland was cleared?
Soils were left eroded and leached of its nutrients.
| Resulting in thin, less fertile, peaty podsols
99
What was the result of podsolization?
Hardy plants colonised upland areas- grass, bracken and heather (mixed moorland vegetation)
100
Describe heather?
A valuable, evergreen forage plant. Major food douse for hill sheep. Staple diet of red grouse.
101
What are the 4 heather phases?
Pioneer phase
Building phase - most productive
Mature phase
Degenerate phase
102
How and why is the heather burnt?
In a 10-15 year rotation in areas of 1 hectare at a time.
| Controlled burning is to keep heather in its building phase
103
What would happen if the burning stopped?
Secondary succession l
| Scrub and birch followed by climax community
104
How much sunlight gets to the forest floor in the rainforest?
As little as 1%
105
Adaptations of plants on the forest floor?
Large flat leaves
106
Adaptation of Mimoca Pudisa
Folds its leaves inwards or droops when leaves surface is contacted
107
How are the canopy leaves adapted?
Approx 80% have Drip tip leaves- sheds water quickly
108
Example of symbiotic relationship?
Epiphylls growing in puddles on leaves surface, steeling sunlight
109
Example of sustainable tourism?
Loss of 80% orang-Utan habitat in 20 years.
| Sepilok Rehabilitation centre- 1964
110
Background to oil spill?
2010 Deepwater Horizon Oil rig disaster in the Gulf of Mexico
Worlds largest accidental oil spill
111
Environmental consequences of oil spill?
| Economic?
48km plume of oil
Impact on food webs
Marshland ecosystems covered in black poisonous sludge
80% of jobs in fishing and tourism threatened
112
Oil clean up?
Pom-poms- collected oil around rocky areas
Containment booms- trapped oil by sticking to booms
Natural processes- weathering and tidal action
3/4 of spill removed
113
Which species did the oil threaten?
```
Coral reefs
Marshlands and coastal grassland
Black mangroves
Turtle species- 500 dead
Blue fin tuna
```
114
The Antarctic Treaty?
1959
| Twelve nations signed
115
Figure on tourism to Antarctica?
Tripled in last 20 years
116
Endangered fish?
Patagonian toothfish
117
Which cities are at threat from rising sea levels?
New York and Venice
118
Waste differences between developed and developing countries?
Developed produce 30 times more waste
