Soil acidity (and acidity of anything else, for that matter) is measured on a scale of 1 to 14. Everything below 7 is considered to be acidic. Everything above is considered to be alkaline. Most garden plants thrive at a pH between 6 and 7.5. The reason a pH between 6 and 7.5 is optimal for garden plants is that between 6 and 7.5, phosphorus in the soil is soluble - meaning that it dissolves in water and is taken up by plant roots.
Some of the factors that affect the rate at which particles diffuse include: the particle's molecular weight, temperature, concentration difference, diffusion distance, permeability and surface area. Pressure is also known to affect the rate of diffusion since it increases the speed of molecules.
Biotic and Abiotic Factors Influenceâ¦ Both abiotic and biotic factors determine both where an organism can live and how much a population can grow. A limiting factor is a factor that restricts the size of a population from reaching its full potential. The amount of food & water in a habitat is an example of a limiting factor. Other factors include geographical space, predation, climate, competition (for prey, food, mates) etc.