Which is a tropical food crop requiring a temperature of 270 C and a rainfall of more than 100 cm?

(1) Wheat

(2) Maize

(3) Rice

(4) Barley

Coffee is a

(1) Sub-tropical shrub

(2) Warm temperate shrub

(3) Tropical shrub

(4) Cool temperate shrub

Contour plowing helps in

(1) stopping floods

(2) growing crops

(3) soil conservation

(4) checking landslides

Black soil is mainly related to the crop of

(1) cotton

(2) sugarcane

(3) tea

(4) coffee

Humus is a type of

(1) fossil seen on the rocks

(2) decaying organic matters in soil

(3) fertilizers applied in soil

(4) special growth found in plants

A significant quantity of upper soil is formed by

(1) Igneous rock

(2) Sedimentary rock

(3) Metamorphic rock

(4) Biological degradation

In a desert region, soil erosion can be checked by

(1) Tree plantation/afforestation

(2) Crop rotation

(3) Contour ploughing

(4) Using farm manure

Alluvial soils are usually

(i) Rich in nitrogen

(ii) Poor in humus

(iii) Highly fertile

(iv) Easy to plough

(1) (i), (ii) and (iv)

(2) (ii), (iii) and (iv)

(3) (i), (iii) and (iv)

(4) (i), (ii) and (iii)

The land which is not cultivated every year though it is suitable for cultivation :

(1) Wasteland

(2) Pastureland

(3) Fallow land

(4) Cultivable wasteland

The organic matter present in the soil is known collectively as

(1) Hydrocarbons

(2)Podsols

(3) Humus

(4)Colloids

Which one of the following soils is used for the production of bricks?

(1) Peaty and organic

(2) Saline

(3) Laterite

(4) Red and yellow