Which element is responsible for causing soil salinity ? At what concentration does the soil become saline ?
Soil salinity is the salt content in the soil.
Salts are a natural component in soils and water.
The ions responsible for salination are : $\mathrm{Na}^{+}, \mathrm{K}^{+}, \mathrm{Ca}^{2+}, \mathrm{Mg}^{2+}$ and $\mathrm{Cl}^{-}$.
Soil becomes saline at a high soluble salts concentration $(0.2 \%$ or above) or $500 \mathrm{ppm}$ sodium (sodic soil).
Why do high altitude areas have brighter sunlight and lower temperatures as compared to the plains ?
Consider the following statements $(A - D)$ each with one or two blanks.
$(A)$ Some snails go into _____$(i)$_____ to avoid ____$(ii)$_____ related problems.
$(B)$ Since small animals have a ____$(iii)$___ surface area relative to their volume, they tend to lose body heat
_____$(iv)$______ when it is cold outside.
$(C)$ Next to temperature, _____$(v)$____ is the most ecologically important environmental factor.
$(D)$ Every ____$(vi)$____ the famous Keolado National Park in Rajasthan host thousands of migrating birds.
Which one of the following option gives the correct fill ups for the respective blank numbers from $(i)$ to $(vi)$ in
the statements?
List the various abiotic environmental factors.
Which of the following ecological factor exerts a direct effect