The role and mechanism of commercial macroalgae for soil conditioner and nutrient uptake catalyzer

The growing demand for chemical fertilizer with low utilization and environmental pollution has been issuing challenges to sustainable production of agricultural field. Due to internal nutrient elements and active substances, macroalgae have drawn the interest of agricultural and algal researchers. However, their major functions seem to center on improvement of nutrient utilization efficiency, more than a simple nutrient replacement for amount of fertilizer. In view of excessive fertilizer along with a series of side-effects, this review reports the application roles of macroalgae in agriculture, provides the positive evidences of the extracts on the soil for amendment, and plants for nutrient uptake. Commercial macroalgae will be such an economic and efficient materials source for cooperation even part substitution of conventional fertilizers, to manage soil sustainability and crop production. Worldwide, the researches of macroalgal products call for further advance, and their applications to agricultural market remain certain limitation. Aim at this, we expound their mechanisms on soil–plant system for more nutrient utilization efficiency, then analyze the current situation and advance priorities afterwards, to guide macroalgal application and respond to the strategy for controlling the chemical fertilizer.