No evidence that chronic nitrogen additions increase photosynthesis in mature sugar maple forests - Talhelm, A F; Pregitzer, K S; Burton, A J (Ecological applications, 2011)
Keywords: Acer - drug effects; Acer - growth & development; Acer - physiology; Carbon - chemistry; Carbon - metabolism; Carbon Isotopes; Fertilizers - analysis; Michigan; Nitrates - chemistry; Nitrates - pharmacology; Nitrogen - chemistry; Nitrogen - pharmacology; Oxygen - chemistry; Oxygen - metabolism; Oxygen Isotopes; Photosynthesis - drug effects; Plant Leaves - chemistry; Plant Leaves - growth & development; Time Factors; Trees - drug effects; Trees - physiology; Michigan