Identify the ecologist from the given hints

(i) Has carried out long-term ecosystem experiments using outdoor plots

(ii) In his experiments he showed that increased diversity contributed to higher productivity

• Ahmed Khan

• David Tilman

• Stanley Choen

• Ernest Chain

• Ernest Chain

The rate of biomass production and the rate of production of organic matter during photosynthesis are called respectively

• Total productivity, primary production

• Gross primary productivity, gross secondary productivity

• Net primary productivity, secondary productivity

• Net productivity, gross secondary productivity

• Net productivity, gross secondary productivity

Which of the following ecological pyramids is generally inverted?

• Pyramid of energy

• Pyramid of biomass in a forest

• Pyramid of biomass in a sea

• Pyramid of numbers in grassland

The pioneer species in xerarch and hydrarch succession are respectively

• Lichens and sedges

• Phytoplanktons and sedges

• Lichens and zooplanktons

• Lichens and phytoplanktons

• Lichens and phytoplanktons

The gross primary productivity of an ecosystem is 170 tons organic matter and amount used in respiration is 50 tons. Calculate the net primary productivity of the ecosystem.

• 120 tons

• 100 tons

• 70 tons

• 12 tons

• 12 tons