Long-term effects of elevated atmospheric CO2 concentration on soybean phosphorus acquisition and soil phosphorus transformation in the rhizosphere of soybean
Phosphorus(P),the second important plant nutrient,regulates crop adaptation to climate change.The organic matter content of Mollisols in different areas of Northeast China is quite different,which greatly influences crop nutrient absorption.How-ever,few studies have investigated the long-term effects of elevated CO2 concentration on soybean growth,soil phosphorus fraction and relevant microbial mechanisms with different organic matter content of Mollisols.The study used open-top growth chambers to mainly investigate the effects of elevated CO2 on soil phosphorus fractions and relevant functional genes in Mollisols with different organic matter content.The results showed that the response of P uptake of soybean to the long-term elevated CO2 was the same change with different organic matter content,increasing first and then decreasing,while differences existed on P fractions in rhizo-sphere of soybean.Elevated CO2 decreased NaHCO3-Po fraction in high-SOM(H-SOM)soil,however,elevated CO2 favored the accumulation of organic fraction(NaHCO3-Po and NaOH-Po),reduced inorganic fraction(NaOH-Pi)in low-SOM(L-SOM)soil.In addition,elevated CO2 concentration increased the copy numbers of phoC by 53.0%in H-SOM,but increased the copy numbers of pstS by 44.4%in L-SOM.Therefore,under long-term climate change,soybean can meet the P demand through organic P mineraliza-tion by soil microorganisms in H-SOM,while inorganic P and relevant functional genes are affected in L-SOM.
万方数据
维普
