Effects on microelements and microorganisms in rhizosphere and non-rhizosphere soil of the Masson pine successive rotation

Through the pair method,for different generations(1,2) and ages(8,9,15,18,20 a),we studied the effects on available microelements,microorganisms and biochemical roles in rhizosphere and non-rhizosphere soil of the Masson pine successive rotation.The results as follows:after successive rotation,the available microelement contents in rhizosphere and non-rhizosphere soil assumes the trend of escalation,and the difference of exchangeable Mg2+ and available Fe content between the 1stand the 2nd generation reached the remarkable level.The quantities of the bacteria,actinomycetes,fungus and the total microorganisms of rhizosphere and non-rhizosphere soil in the 2nd generation is higher than that of the 1st generation,and the difference of the quantities of actinomycetes and fungus between the 1st and the 2nd generation reaches remarkable or the extremely remarkable level.Among the soil microbes in rhizosphere and non-rhizosphere soil of the 1st and 2nd forest,bacteria were predominant,actinomyces were the next,and fungi were the least.We study the effects on the biochemical roles in rhizosphere and non-rhizosphere soil,and find that after successive rotation,regardless of rhizosphere or the non-rhizosphere,the nitrification of the rhizosphere and non-rhizosphere soil tends the rise,but the ammonification tends the drop,and the difference of nitrification and ammonification in rhizosphere and the difference of ammonification in non-rhizosphere soil between the 1st and the 2nd generation reached the remarkable level.