Well the soil classification is usually done on the basis of particle sizes and composition of soil.
<span>Clay </span>usually consists of particles less than 0.075 mm in size. It is a sticky soil and shows great changes in volume with variation in its water contact. It also shows considerable strength when air dried.
<span>Silt </span>has larger particles than clay and are mainly inorganic in nature. The particle size is less than 0.075mm and exhibits slightly plastic or non plastic behaviour.
Humus is soil consisting of dead and decaying organic matter. It is mainly organic in content but some inorganic particles may be mixed in it. The top soil in a tropical forest may be considered as humus.
Answer:
A particular population limiting factor or factors must have been removed
Explanation:
The population of the birds must have been kept between 30 and 50 individuals by population limiting factors such as the presence of predators within the community or competition for resources such as food or spaces.
For the population to shoot up to 90 all of a sudden, it may be that one or more of the population limiting factors has been removed from the population. <u>It could be that a major predator has been removed from the community or the competition for food/space is now significantly reduced due to more food/space in the community. </u>
The Answer is A but im only about 5% sure about my answer
You might be able to find the differents in these.