alluvial soil
The correct answer is... Bacteria in the plant nodules convert nitrogen from the soil into molecules the plant can use.
excretion
root nodules
oxygen
Soil air has a higher concentration of Carbon Dioxide; plants feed on this and convert it into Oxygen during Osmosis, which is why there is a higher concentration of Oxygen in the atmosphere.
Osmosis is the movement of water molecules from an area of high concentration to an area of low concentration through a semi-permeable membrane. In the case of plants, water moves from the soil into the root through osmosis because the root cells have a higher concentration of solutes than the surrounding soil. This creates a concentration gradient that drives the movement of water into the root.
Old soil is more weathered and mature, with well-developed soil horizons and a higher concentration of nutrients. In contrast, young soil is less weathered, often has less distinct soil horizons, and may have lower nutrient levels. Old soil typically has better drainage and a higher capacity for supporting plant growth compared to young soil.
The nitrogen cycle aids plants through bacterial nodules in soil. These nodules contain nitrogen-fixing bacteria, such as Rhizobium, that convert atmospheric nitrogen into a form that plants can use for growth and development. This symbiotic relationship between plants and nitrogen-fixing bacteria helps increase nitrogen availability in the soil, benefiting plant growth.
Water moves from the soil into the roots of the plants due to a process called osmosis. This occurs because the concentration of water is higher in the soil than in the roots, so water naturally moves from an area of higher concentration to an area of lower concentration. This helps the plants absorb the water and nutrients they need for growth and survival.
They have nitrogen fixing bacteria in their root nodules, so the fertility of the soil is improved.
Bacteria that exist in the root nodules of some plants can absorb nitrogen from the air in the soil. One notable example is the Rhizobia that lives in nodules on soybean roots. Similar root systems exist in clover and alfalfa.
Legumes have nirtifying bacteria in their roots, but mostly they are found in the soil.