B13 Flashcards
Define ecology
Study of organisms in relation to all aspects of their environment
How do plants live?
Plants do not live in isolation, they interact with the physical environment, with other plants, with animals and with other microbes.
What factors impact the fate of plants?
Biotic and abiotic environment has impact on fates of species.
How do plants typically grow?
As part of a population with different species growing together in a plant community.
What factors effect plants?
All aspects of its immediate environment. Landscape, climate, latitude and longitude, soil, other organisms.
What is the earths surface composed of?
Rich and chasing mosaic of diverse habitats. Natural selection has produced a wealth of species of plants, animals, fungi, protists and prokaryotes.
What determines if a plant will survive?
Adaptations for particular environmental aspects. Natural selection to be able to outcompete organisms.
Why do plants grow in populations?
They are synergistic, they can undertake sexual reproduction, individuals may produce pollen but not enough to sustain a pollinator.
Do populations exist in isolation?
No they coexist with populations of other plants, animals, fungi, protists and prokaryotes. All these populations together make a community, community is characteristic of a habitat. Community + physical, non-living environment = ecosystem
What is a habitat?
Set of conditions in which an organism completes its life cycle. Abiotic and biotic. For migratory organisms, the winter and summer areas and migration routes are habitat components. No plant is migratory. No plant is migratory, but portions of plants are, spores, pollen, fruits and seeds
What is the role of the abiotic habitat components climate?
Climate, which is critically important to all organisms, most species restricted to certain regions because of climatic conditions. Many components in climate including temperature, rainfall, wind, humidity
What is the role of the abiotic habitat component soil factors?
Soils formed by breakdown of rock, young soils are N deficient and sandy, most minerals locked in the rock matrix, little water holding capacity. Variations in bedrock type result in varying soil pH.
What role do pioneer species play in abiotic habitats?
These species tolerate severe conditions, they are usually associated with N fixing prokaryotes, they improve soil quality. Addition of dead material, after many years a thick soil results. Distinct soil profile of 3 layers or horizons.
What role does latitude play in abiotic habitats?
Regions at high altitudes are similar to those at high latitude. The conditions include high winds and poor soil. With cold and short growing season. Intense uv light.
What impact do natural catastrophes have on abiotic habitats?
Disturbances produce significant change in an ecosystem, affecting biotic factors. Fire is a common component of many dry ecosystems, many plants within these regions are fire resistant as a result of natural selection. Thick bark or cones that only open after fire.
What is an increasing abiotic component in habitats?
Human disturbances
In biotic habitats how does the plant itself influence the habitat?
In woodlands, trees modify the habitat by growing a dense canopy of leaves this reduces light regime on woodland floor. Early flowering spring plants must complete their lifecycle prior to the canopy closing.
What impact can other plant species have in habitats?
They can have beneficial impacts which is mutualism or detrimental impacts which is competition. Sharing a limited amount of available light and nutrients leads to competition. In a stable ecosystem, competition is reduced since each species is specifically adapted to fill a particular niche, many species overlap in their tolerance ranges.
What organisms other than plants are biotic habitat components?
Animals, fungi, bacteria
What is mutualism in plant ecology?
Animal receives nectar, pollen or fruit and plant benefits from their transfer
What is commensalism in plant ecology?
One species benefits, other is unaffected
What is predation in plant ecology?
One species benefits, other suffers
How are the interrelationships between plants and fungi or bacteria?
They can be detrimental or mutualistic.
What are ecosystems?
Ecosystems are extremely complex, interactions between plants and other organisms are many and varied.
What do water voles do in their biotic habitat?
They engineer their habitat, through creating feeding stations of vegetation, latrines of faecal pellets, underground burrows, runways in Bankside vegetation
What factors affect how population structure in plant ecology is organised?
Geographic distribution of a plant species depends on its ability to disperse. Ability to tolerate biotic and abiotic conditions in the new area. At any time one factor can be a limiting factor in plant survival
What are the types of local geographic distribution?
Random, clumped, uniform
What is random geographic distribution?
Shows no obvious pattern
What is clumped geographic distribution?
Where there is small or large spacing between individuals
What is uniform geographic distribution?
There is a regular pattern
How is age structure linked to population structure?
Age structure is the demography. Relative proportions of young, middle-aged, and old individuals. Affected by generation time and intrinsic rate of natural increase.
What is physiognomic structure?
Physical size and shape of the plants and their relation to each other and the physical environment
What is raunkiers life forms?
Classification according to means of surviving stressful seasons. Formed based on location of meristem relative to soil surface
What factors affect ecosystem structure?
Temporal effects and seasonality
What is species competition?
Number and diversity of species that coexist in an ecosystem.
What factors affect species competition?
Climate, soil, species tolerance range. Competition can be intense but natural selection has resulted in habitat and niche partitioning, so each species occupies a narrow portion of the various resource gradients.
What overcomes competition?
Niche partitioning
What trophic level are plants?
Base of food web
What are biomes?
Extensive groupings of many ecosystems characterised by the distinctive aspects of dominant plants
What can biomes vary from?
Simple artic tundra to complex grasslands, temperate forests and tropical rainforests
What two abiotic factors strongly influence complexity and physiognomy?
Climate and soil
Where is physiognomy similar but species composition varies greatly?
A particular type (e.g. grassland) may occur in various regions of earth - the same set of climatic and soil factors occur in these regions.
What are temperate grasslands dominated by?
Grasses and large animals and devoid of trees. Each area has a characteristic suite of species adapted to the grassland niche.
What is convergent evolution?
Independent development of beneficial traits
What factors determine locations of earths biomes?
World climate, position of continents.
What link do biomes and world climate have?
Atmospheric distribution of heat, atmosphere develops convection currents. Heat distributed from tropics to temperate regions and poles. Hot air rises and draws in cold air underneath. Causes wind
Biomes and the continental climate
Size of a land mass influences the weather it receives. Continents cause air to rise, cool, and drop precipitation. If topography flat, rain evenly distributed. Presence of mountains also important, cause rain shadow
How does water flow in the world?
Giant circular currents driven by air circulation patterns, ocean currents distribute heat from tropics to poles, as warm tropical surface it increases air humidity. Gulf stream keeps Britain warm.
What factor determines regional climate?
Latitude. Warm and humid at equator, cooler and drier towards poles, present position of todays continents determines biomes
World biomes are?
Moist temperate, dry temperate, polar, tropical
What are the regional extent of biomes determined by and classified according to?
Determined by climate and classified according to physiognomy.
What structures did the world biomes have?
Climate and vegetation structure
