How Internal (Plant) and External (Environmental) Factors Influence Nutrient Supply to the Plant Root by Mass flow The plant loses water through transpiration. That's why there creates a vacuum in the plant. Then the plant absorbs water from the soil. This phenomenon is known as mass flow. It also takes the nutritional substances dissolved in the water at that time. As there happens a plant-environment interaction, there are a wide range of plant and environmental factors which can influence the nutrient supply to the roots of the plant Internal Factors or Plant Factors Species and Variety Water absorption by mass flow depends on the species and variety of the plants. Such as Eucalyptus absorbs much water than others. High yielding varieties uptake much water. In this way, it influences the nutrient uptake. Leaf Surface and Age of leafs Leaf Surface and leafage affect transpiration. Broader and younger leaves mean more transpiration. And transpiration is directly related to mass flow. More transpiration means more mass flow and more nutrient uptake. Influx to the Apoplasm For effective use of the nutrients, they need to reach the stele for transportation to the entire plant body. Endodermis creates a barrier to reach the nutrient through apoplasm. Plant Development Stage Transpiration and water uptakes depend on the age of the plant. So Nutrient uptake is affected. Metabolic Activity Ion accumulation depends on the expenditure of energy through metabolic activity like respiration. Thus ion uptake can be affected by metabolic activity. Such as, with lowering the oxygen tension, the uptake of potassium and phosphate is decreased. External or Environmental Factors Air Humidity As the humidity of air decreased, the plan losses more water through transpiration. On the other hand, mass flow increased. After all the nutrient uptake is affected. Concentration of the Solution If the available water is highly concentrated with the nutrient then the plant will get more nutrients. So, applying fertilizer can increase nutrient uptake. Effects of pH Nutrient uptake is largely affected by the pH of certain soil. pH influences the cations and anions of the solution. P, Zn, Fe are less available in alkali soil. Again Al3+ and Mn2+ inhibits the plant growth in the acid soil. Temperature Due to high temperature the rate of transpiration increases. Thus water starts absorbing more water through mass flow. Consequently, it increases the nutrient uptake. Soil properties Soil texture, structure, porosity can affect the nutrient uptake.