兰考泡桐和刺槐幼苗最适营养需要的研究

按稳态营养理论和方法,本文研究了兰考泡桐(Paulownia elongata)和刺槐(Robinia pseudoacacia)幼苗的最适营养需要。通过每天测定和调整培养液pH值和电导率,及时补偿消耗的营养物,幼苗体内营养状况和最大生长速率均保持稳定。兰考泡桐幼苗每天生长率高达25％以上,刺槐达15％。营养物利用率90％以上。确定兰考泡桐幼苗最适营养物比例为100N:75K:18P:7Ca:8.5Mg;刺槐为100N:60K:15P:8Ca:9Mg。本文还讨论了最适营养研究在育苗和林地施肥应用的前景。

A STUDY ON OPTIMUM NUTRIENT REQUIREMENTS OF PAULOWNIA ELONGATA AND ROBINIA PSEUDOACACIA SEEDLINGS

The optimum nutrient requirements (macronutrients) for maximum growth rate of Paulownia elongata and Robinia pseudoacacia have been studied based on the principles of steady state nutrition, by using a growth technique that the nutrients consumed were compensated by means of daily determinations and adjustments of pH and conductivity titrition.The seedlings were grown under controlled conditions, the nutrient status in seedlings and its maximum growth rate remained stable during the experimental period. To obtain a high relative growth rate over 25% per day in Paulownia elongata and about 15% per day in Robinia pseudoacacia, suitable proportions by weight may be 100N:75K:18P:7Ca:8.5Mg and 100N:60K:15P:8Ca:9Mg respectively.The optimum nutrient requitements by weight and its perspective of applications in fertilizations of nursery and young forest stands were also discussed in this paper.