Question

Comment upon the following: (i) Biodiversity hotspots (ii) Productivity.

Hint:

A hotspot needs both high uniqueness and high threat; productivity splits into what is made (gross) and what is left over after the plant's own use (net).

Answer 1

Step 1: Biodiversity hotspots, what they are.
A biodiversity hotspot is a region of the world that has an exceptionally large number of species found nowhere else (high endemism), but which is also under serious threat from habitat loss, making it a priority for conservation.

Step 2: Biodiversity hotspots, examples and importance.
The Western Ghats and Sri Lanka, along with the Indo-Burma region, are recognised biodiversity hotspots within India's neighbourhood. Because such a large fraction of unique species is packed into a small area, protecting hotspots is a highly efficient way to save global biodiversity with limited conservation resources.

Step 3: Productivity, what it is.
Productivity in ecology is the rate at which biomass (organic matter) is produced by organisms in an ecosystem, per unit area, over a period of time, and it forms the base of the energy that supports the whole food chain.

Step 4: Productivity, its two main types.
Gross primary productivity (GPP) is the total rate of production of organic matter by producers through photosynthesis. Net primary productivity (NPP) is what is left after subtracting the amount the producers themselves use up in respiration (NPP = GPP minus respiration), and it is this NPP that is actually available to the herbivores that eat the producers.

Final Answer:
Biodiversity hotspots are species rich but threatened regions (like the Western Ghats) that are conservation priorities, while productivity is the rate of biomass production in an ecosystem, split into gross and net primary productivity.