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Chapter 25: Populations and Ecosystems - Coggle Diagram
Chapter 25: Populations and Ecosystems
Concepts
Individual plants never exist in isolation in a habitat; they live in a population. Different population coexist with other populations.
Many populations together form a
community
Populations are not usually stable and always changing
ecology
is the study of organisms in relationship to all other aspects of their surroundings
While studying plants it is important to analyze the structure, metabolism, and diversity in terms of adaptation and fitness.
Plants in relationship to their habitat.
habitat
- set of conditions in which an organism completes its life cycle.
for migratory animals their summer, winter, and routes are all components. Deciding how much of the surrounding area is Considered part of the habitat is still up for debate
Plants are not migratory, but portions of plants such as spores, pollen, fruits, seeds, and vegetable propagules move throughout the habitat.
Operational habitat
- aspects of the habitat that definitely affect a plant
Habitat components- 2 types
abiotic
and
biotic
Abiotic components are nonliving And our physical phenomenon: climate, soil, latitude, altitude, and disturbances such as fires, floods, and avalanches.
The average temperature of a habitat is not as important as its extremes
The growing season of an area Is often determined by the date of the last severe killing frost in the spring in the first killing frost of autumn. The light of the growing season must be adequate for sufficient photosynthesis, growth, development, and reproduction; if not, a reproductive population cannot survive even if it can tolerate the temperature extremes of winter and summer
Soils are formed by breakdown of rock. Initially the resulting soil is thin and virtually identical to the parent rock and its chemical composition. The first plants that invade a new soil, called
Pioneers
must tolerate severe conditions.
The soil is Sandy and has little water-holding capacity. After many years, soil may result that has a distinct soil profile with three layers or horizons.
horizons
A
-The uppermost horizon and is sometimes called the zone of leaching; it consists of litter and debris, and as this breaks down, rainwater washes nutrients from a downward into the next layer
B
- The second layer, also known as the zone of deposition. Where materials from the "A" horizon accumulate. It is rich in nutrients and contains both humus and clay
C
- The third which is composed mostly of parent rock and rock fragments where is young soil's differ because of the chemical nature of parental rock, older, more mature soil's are less diverse. As the rock Weathers, essential elements are absorbed by route trapped in the plant body; nonessential elements or leads the way. As the plants or their parts die, they decay slowly, releasing the Is sensual elements that re-enter the soil.
Biotic components are living factors: the plant itself, other plant species, and species of animals, fungi, protests, and prokaryotes.
Several individuals of either just one or several species occur together is a possibility for interaction is created is the interaction is basically beneficial for both organisms it is described as
mutualism
. If the interaction is disadvantages it is
competition
Competition is a situation in which two populations do not grow as well together as they do separately because they use the same limited supply of resources. Many plants are believed to compete with others for light, soil nutrients, water, and the attention of pollinators and see dispersers etc.
competitive exclusion: Which ever species is less adapted is excluded from the ecosystem by superior competitors.
niche
describes both the range of conditions necessary for persistence of the species, and its ecological role in the ecosystem
Ecotypes- to test whether they really exist,
transplant experiments
are performed. Plants from each side or transplanted to the alternate side, and plants from both sides may be growing together in a
common garden
as an intermediate side
Organisms other than plants
frugivores
Fruit eating animals that Aidan C dispersal. Also benefits both species as long as the animal does not show the seeds and digest the embryos.
commensal relationships
One species benefits and the other is unaffected, or also common between plants and animals. When birds build nests in trees the birds benefit in the trees usually unharmed. One sticky fruits or seeds such as cocklebur stick to animals for feathers and then I disperse the plant benefits and the animals is unharmed
Predation
One species benefits and the other is harmed the species that benefits seek out the other and uses it specifically for food or some other form of resource
Animals that eat plants are
herbivores
in the process is
herbivory
, but it is often more precisely delaminated as
browsing
(eating twigs and leaves of shrubs – dear, giraffes) or
grazing
(eating herbs – sheep, cattle).
Structure of Populations
Limiting factor- anything that constrains a population's size and slows or stops it from growing. i.e. a lack of warmth in winter
Individuals have one of three types of local distribution random, clumped, or uniform
Random distribution
is used whenever there is no obvious, identifiable pattern to the position of individuals. A random pattern has no predictive value; knowing the position of one plant does not let you estimate the position of another plant
Clumped distribution
Are those in which the spacing between plants is either small or large, but rarely average. This can result from many factors seeds of a plant often found near the plant, not a uniform or random distances from it.
Uniform distributions
Are the types that occur in orchids in tree plantations; all individuals are evenly spaced from their neighbors. And natural populations, uniform distributions are not extremely common those that do occur are thought to result from intraspecies competition
Zones can also be established at least theoretically by the release from the plant of chemicals that inhibit other plants such chemicals are called Allelochemics And the inhibition is allelopathy
Age Distribution, it's demography – the relative proportions of young, middle-aged, and older individuals. Analysis of age distribution has been applied mostly to animal populations and may be difficult to apply to plant plants, but the fundamental aspects are important and easy to understand.
Generation time, the length of time from the birth of one individual until the birth of its first offspring, affects the rapidity population growth: animals have a generation time of one year or less and can increase rapidly, whereas most carnivores and angiosperm trees must be several years old before they produce their first seeds
Intrinsic rate of natural increase or biotic potential, is the number of offspring produced by an individual that actually live long enough to reproduce under ideal conditions. Even with optimal conditions, a large percentage of seeds do not germinate, and many seedlings die before they are old enough to reproduce; therefore, the biotic potential does not equal the number of seats produced.
carrying capacity
can be defined as a species' average population size in a particular habitat. The species population size is limited by environmental factors like adequate food, shelter, water, and mates. If these needs are not met, the population will decrease until the resource rebounds.
K selected species- Redwoods, Douglas firs, and bristlecone pines are good examples
R selected species- Typically annuals or small shrubbery perennials because the district or habitat gradually change back into a crowded one that is no longer suitable for the pioneer r selected species
The structure of ecosystems
Physiognomic structure- Constituted by the physical size and shape of the organisms and their distribution in relation to each other into the physical environment
Temporal structure
-the changes that ecosystem undergoes with time cards to toot its temporal structure; the time span can be as short as a day or can compass season two decades. For animals, a daily cycle can be especially obvious, with some animals active at night and others doing a day. But the plants also have daily rhythms of flower opening and closing
Species composition
- First of the number and diversity of species that coexisting an ecosystem, and it depends on whether the climate is mild or stressful, the soil is rich or poor, and the species tolerance ranges are broad or narrow. Stressful climate with poor soil support a low temperature species because so few species are adapted to such conditions. On the other hand, Mount Clemens and rich soil support and abundance of species because most plants have tolerance ranges that include such climate and soil conditions. Competition is intense.
Trophic levels
- Basically feeding levels. Each ecosystem contains some members, auto troughs, that bring energy into the system photosynthesis is by far the dominant method accounting for virtually all energy and put. Green vascular plants are most important, but I'll tree and cyanobacteria carry about 1/3 of all photosynthesis worldwide
Primary producers
- Also known as auto troughs they are the first step of any food web they are the energy and nutrients apply for the herbivores.
Primary consumers
- Sometimes called secondary producers. Small herbivores such as insects mice and squirrels are prayed on by carnivores, the
secondary consumers
Tertiary consumer
- These are the top carnivores, animals such as walls, Lions, and hyenas that are not print upon by other animals
decomposers
- Such as fungi and bacteria, breaks down the remains of all types of organisms even those of other decomposers
As plants photosynthesize, energy and carbon compounds into the ecosystem. As plants are eaten, their energy and carbon compounds moved to the herbivore traffic level, then to the carnivore traffic levels, and finally on to the decomposers. This is referred to as the
Energy flow
and the
Carbon flow
of the ecosystem.
At each that much of the food is used in respiration resulting in the production of ATP, heat, carbon dioxide, and water. The carbon dioxide is released back to the atmosphere, where it can be used in photosynthesis again; the energy temporary contributes to warming of the planet, but it is ultimately radiated into space
