Potassium: a neglected nutrient in global change

Abstract Aim Potassium ( K ) is the second most abundant nutrient in plant photosynthetic tissues after nitrogen ( N ). Thousands of physiological and metabolic studies in recent decades have established the fundamental role of K in plant function, especially in water‐use efficiency and economy, and yet macroecological studies have mostly overlooked this nutrient. Methods We have reviewed available studies on the content, stoichiometry and roles of K in the soil–plant system and in terrestrial ecosystems. We have also reviewed the impacts of global change drivers on K content, stoichiometry and roles. Conclusions The current literature indicates that K , at a global level, is as limiting as N and phosphorus (…