1.Who identified Blue-Green Algae (BGA) as a nitrogen-fixing organism in rice fields?
2.Which organisms are responsible for breaking down organic material in waterlogged soils?
3.Which nutrient is commonly referred to as the 'chemical policeman' in plants?
4.Which nutrient elements are considered to function as energy carriers in biological systems?
5.Which mineral soil surface horizon is characterized by being excessively thin, pale in color, or having a low organic matter content?
6.Soil Organic Matter (SOM), containing approximately what percentage of organic carbon, is essential for supplying both macro and micronutrients?
7.Phyllosilicate minerals are structured from which two types of sheets?
8.Soil colloids have charges on both their internal and external surfaces. Which type of charge is generally predominant?
9.Which soil order is not commonly found in Pakistan?
10.Identify the incorrect statement from the following options:
11.Which soil property primarily regulates the accessibility of vital nutrients to plants?
12.Which of the following are key components of conservation agriculture that enhance water use efficiency in dryland farming systems?
13.What term describes the systematic planning, allocation, and utilization of water resources?
14.What percentage of water typically makes up the biomass of plants, considering water is the primary component of all living organisms?
15.How are soil pores classified according to their diameter?
16.Based on the proportions of sand, silt, and clay, soils are categorized into how many textural classes?
17.Which type of particles have diameters that fall between 0.002 mm and 0.02 mm?
18.What term describes the organized study of soil in both field and lab settings, including its description and categorization based on classification systems?
19.Which soil type is characterized by swelling clays that cause the formation of cracks due to their high content of expansive clay minerals?
20.Out of the twelve recognized soil orders worldwide, which six are commonly identified in various regions?