Sustaining environmental quality

Question

How do species interact?

Answer 1

Species interact in 5 major ways:

Interspecific competition
Predation
Parasitism
Mutualism
Commensalism

Answer 2

1. the latitude in terrestrial communities
2. pollution in aquatic systems

Answer 3

1. Interspecific competition; interaction in which species compete for the same resources. Humans compete with many other species for space,food etc.
2. Predation: one species feeds directly on the members of other species.
3. Parasitism: one organism feeds on the other by living on the host.
4. mutualism: interaction which benefits both (pollination by honey bees)
5. commensialism; interaction where one benefits from the other without effect on the other. (fish that live on skin bigger fish)

Answer 4

Each animals has an ecological text-decorationniche, which includes everything that an animal needs to survive and reproduce. When they compete their niches overlap.

Answer 5

adaptation of competing species that divide the resource and reduce competition: they share it but at different times, or different ways (see example birds using different parts of the tree p 105).

Answer 6

It can evolve in many ways to avoid predators, use chemical warfare (poisonous, irritating, foul smelling, bad tasting chemicals) and evolve warning coloration.

Answer 7

1. clumps: when resources are found in patches --> most common one
2. uniform dispersion; a resource is scarce
3. random dispersion: plentiful resources.

Answer 8

Too much or too little of a physical or chemical factor limits or prevents the growth of a population , even if all other factors are optimal.

examples can be: temperature, nutrients, oxygen level in water.

Answer 9

The combination of all limiting factors on a population. All the limiting factors also determine an area's carrying capacity; the maximum population of a given species that a particular habitat can sustain.

When there are few limiting factors (few predators, ample food supply) an population can grow exponentially (J-curve).
Eventually this will also reach the carrying capacity and then form an s-curve: logistic growth.

Answer 10

- reproductive patterns: fast/slow, much/little offspring.
- density dependent factors: infectuous diseases , competition for resources.
- density independent factors: (effects are not dependent on the density of the population) floods, freeze.

Answer 11

Stable: size stable around carrying capacity (often in habitats with little variation in circumstances over the year).
Irrupt: high peak, then crash to stable lower level. short lived, rapidly reproducing species such as algae and insects. Habitat: large seasonal changes or nutrient availability.
cyclic: boom-bust cycles. population rises and falls over a longer period of time (e.g. hares rise and fall in 10-year cycles). This can be influenced by top-down regulation (decline in size by predators) or bottom-up: decline in size by scarcity in resources.
irregular: changes in population size with no recurring pattern

Answer 12

Facilitation; species make area suitable for other species (but less suitable for itself) e.g. mosses building up soil.
Inhibition: early species hinder the establishment of certain other species (e.g. toxic spreading trees)
Tolerance : plants in later stages of succession are largely unaffected by plants that came in during earlier stages (because they are not in competition for same resources, e.g. shade tolerant plants growing under large trees).

Answer 13

increase biodiversity
increases richness and interaction among species
this interaction increases sustainability by promoting populationcontrol
increasing the complexity of food webs
This enhances the energy flow and nutrient cycling
it's natural ecological restauration

Answer 14

text-decorationInertia, or persistence: the ability of a living system to survive moderate disturbances.
text-decorationResilience: the ability of a living system to be restored through secondary succession after a more severe disturbance.