According to a latest research, Pakistan is predominantly a dryland country; 80% of its land area is arid and semi arid, 12% sub-humid and 8% under humid climate. Thus , soils of arid & semi-arid regions are vulnerable to a wide range of degradation process. As the case in arid and semi-arid climates elsewhere in south-central/southern Asia and Sub-Saharan Africa; _________________ are among the major causes of soil degradation and desertification?

According to a latest research, Pakistan is predominantly a dryland country; 80% of its land area is arid and semi arid, 12% sub-humid and 8% under humid climate. Thus , soils of arid & semi-arid regions are vulnerable to a wide range of degradation process. As the case in arid and semi-arid climates elsewhere in south-central/southern Asia and Sub-Saharan Africa; _________________ are among the major causes of soil degradation and desertification?

A. Drought stress
B. Accelerated erosion & salinization
C. Depletion of soil fertility and SOM
D. All of the above

Although some acid soils do exist in the northern mountainous regions of Pakistan (Mansehra, Sawat, Dir). Almost all cultivated soils of the country are ________________, with high base saturation and low organic matter content (generally less than 1%)?

Although some acid soils do exist in the northern mountainous regions of Pakistan (Mansehra, Sawat, Dir). Almost all cultivated soils of the country are ________________, with high base saturation and low organic matter content (generally less than 1%)?

A. Alkaline
B. Very much acidic
C. Calcareous
D. both A & C