Answer:
The Bulk density = 1.3 g/cm³
the porosity of the sample is 132 cm³
Explanation:
Given:
Volume of cylinder = 260 cm³
Mass of container and the soil = 403 g
Mass of the empty container = 65 g
Thus,
The mass of the soil is = 403 - 65 = 338 g
Now,
The Bulk density = 
or
The Bulk density = 
or
The Bulk density = 1.3 g/cm³
also,
average particle density for mineral soil is usually given as 2.65 g/cm³
i.e the air present in the given soil sample has reduced its density from 2.65 g/cm³ to 1.3 g/cm³
The mass of the whole sample = Volume × Density
= 260 × 2.65
= 689 gm
but,
The actual mass of the dry sample = 338 g
thus,
Mass of air in the sample = 689 - 338 = 351 g
Therefore,
the volume of 351 g soil =
=
= 132.45 cm³
so the porosity of the sample is 132 cm³
Answer:
Monocropping is the practice of growing the same crop on the same plot of land, year after year. This practice depletes the soil of nutrients (making the soil less productive over time), reduces organic matter in soil and can cause significant erosion which can most probably cause drought.
Answer:
B - sub-Sahara Africa
Explanation:
this region is already very dry - there has been over grazing of animals - deforestation that speeds up desertfication