radiant flux [surface] density

Through the comparison of leaf photosynthetic potential and of photosynthetically active radiation (PAR),leaf nitrogen concentration (Nl),and mass per unit leaf area (Ml) in different canopy layers of un-thinned orchard (UOD) and thinned orchard (TOD),this paper studied the effects of UOD rebuilding on the use efficiencies of PAR and nitrogen,and their relationships to the fruit yield and quality.

通过对成龄苹果密植园和间伐园树冠不同层次和部位叶片光合潜力及辐射通量密度、叶片N含量和比叶重等指标的比较分析,研究了苹果园改造前后辐射能和氮素利用效率差异及其与产量品质的关系。