Question

1. Discuss ecological pyramids, use tropic levels to discuss this process of heat loss.

2. What is chemical cycling?

3. Discuss the following cycles: Carbon cycle, nitrogen cycle, hydrological cycle. Provide examples:

4. Compare and contrast freshwater biomes with marine biomes. Include all examples of each type.

5. Discuss and provide examples of each of the terrestrial biomes.

6. What is a keystone species?

7. Discuss the steps in ecological succession, using appropriate terms and examples.

8. How is biodiversity measured?

9. List several causes of biodiversity loss

Answer 1

1. ecological pyramids

it is a graphyical representation of the different trophic levels of an ecosystem related to one another. the base of each pyramid represents the producers or the first trophic level while the apex represents tertiary or high level consumer , other consumers and trophic levels are in between.

there are 3 types of ecological pyramids.

i) pyramid of numbers- graphical representation of total numbers of individuals of different species belong to each trophic level in ecosystem. pyramid of numbers can be inverted or upright.
upright pyramid-in the case of grass ecosystem because number of organism decreases at successively higher trophic level
inverted pyramid- if we take the situation of a single tree with its dependent insect population.

ii) pyramid of biomass- it is the graphical representation of the total dry weight of organisms of different species at each trophic level at particular time. it can also be upright and inverted.
upright pyramid-if we find biomass decreases at each trophic level if we move from producer to top carnivore.
inverted pyramid- in case of aquatic ecosystem , pyramid of biomass sometimes can be inverted. since phytoplanktonic algae are the primary producer, being single celled organism they cannot accumulate much biomass . so at a given time biomass of phytoplankton is less compared to other herbivore or other consumers. this is the reason of smaller base than the upper structure.

iii) pyramid of energy- basically it reflects the law of thermodynamics. it is the graphical representation of loss of energy at each transfer of another trophic level. so this pyramid is always upright

2.What is chemical cycling?

it is a system of changing fate of nutrients or chemicals between other compounds, states and material. it is the cycling of nutrients within and between ecosystem. changing from inorganic to organic form between and among biotic and abiotic environment components. some examples of chemical cycles are - carbon cycle, nitrogen cycle , phosphorous cycle and biogeochemical cycle.

3.Discuss the following cycles: Carbon cycle, nitrogen cycle, hydrological cycle. Provide examples:

4. Compare and contrast freshwater biomes with marine biomes. Include all examples of each type.

5. Discuss and provide examples of each of the terrestrial biomes.

i) tundra biome- arctic tundra and alpine tundra
ii) desert biome- have annual precipitation less than 30cm.
iii)tropical grassland savanna- rainfall is between 30-50cm per year
iv)temperate grassland- rainfall is less than savanna, grasses as a dominant vegetation
v)tropical rain forest- rainfall exceeds 200cm per year
vi) taiga biome- precipitation in the form of snow fall 40-100cm anually
vIi) temperate decidous- precipitation 65 to 130cm
viii) chaparral biome- precipitation genrally falls within 30-50cm.

6. What is a keystone species?
are those species which show large impact to maintain the structure and nature of community. examples- lion, elephants
7. Discuss the steps in ecological succession, using appropriate terms and examples.

there are six steps in ecological succession;
i) nudation
ii)migration
iii)ecessis
iv)population , aggregation and competition
v)reaction
vi) stabilization.

8. How is biodiversity measured?

biodiversity measurement is described on the basis of species richness and species evenness.

9. List several causes of biodiversity loss

i) habitat loss and fragmentation.
ii) invasive species
iii)overexploitation
iv) disturbance and pollution.