The Variation Of Soil Microbial Functional Diversity And Abundance Of Ammonia Oxidizers In The Degeneration Successional Original Korean Pine Forest

In this study,we analyzed the 0-10 cm and 10-20 cm soil microbial functional diversity and the nitrogen-cycle’s functional diversity by using the Biolog-ECO micro plate method and Real-time Quantization PCR in two original Korean pine forest and degeneration Korean pine forest located in the Liangshui National nature reserve,Dailing District,Yichun City of Heilongjiang province.The main conclusions are as follows:1)The available K,pH,available P,water content,NO3--N and total P were significantly different among forest types.The values of available K and pH in the original broad-leaved forest were higher than the secondary broad-leaved forest,while the available P,water content,NO3--N,and total P were lower than the secondary broad-leaved forest.2)The soil water content,available K,available N and soil temperature were significant differences during different months in the original broad-leaved forest.The AWCD values and microbial diversity in the whole growth season were significant different between different months.The metabolic activity,therefore,the soil microbial communities had been significantly affected by seasonal variation,which were lowest in July and highest in June.Amino acids,polymers,Carbohydrate were the main advantages utilization carbon sources.The PCA showed that soil microbial community carbon metabolic characteristics were divided into three clusters: i)May to May-June,ii)July,iii)August to October;the utilization of Carbohydrate,Amino acids and carboxylic acids were the more sensitive than other carbon sources according for seasonal variations.The soil water content,available P were the main factors that affected the seasonal variation of microbial functional diversity.The soil microbial functional carbon metabolism characteristics were significant different during the growth season in the original broad-leaved Korean pine forest,been influenced by precipitation of different month.3)The available P,available N,total P,soil water content and soil temperature were significant different during the different months in the secondary broad-leaved forest.The AWCD values and Mcintosh index in the whole growth season and microbial diversity were significant different;the metabolic activity of soil microbial communities were lowest in July and highest in June,affecting significantly by seasonal variation.Amino acids,polymers were the main advantages utilization carbon sources;The PCA showed that soil microbial community carbon metabolic characteristics were divided into two clusters: i)May to May-June,ii)July to October;the utilization of Carbohydrate,Amino acids and carboxylic acids were the more sensitive than other carbon sources if season varied.The soil water content,available P,Available N were the main factors that affected the seasonal variation of microbial functional diversity.The soil microbial functional carbon metabolism characteristics were significant different during the growth season in the secondarybroad-leaved forest,because of precipitation in each month significant different.4)The AWCD(Average Well Color Development)values,the diversity indicia and utilization intensity of six categories of carbon sources of soil microbial communities were fundamental same,of which the original forest was significantly higher than those of secondary broad-leaved forest.The Polymers,Amino acid and Carbohydrate were main advantages utilization carbon sources;After the primitive forest degradation and subsequent succession the soil microbial community who was sensitive to the four carbon sources(carbohydrates,amino acids,carboxylic acids and Polymer)for all utilization of carbon sources.5)The amoA gene abundance of ammonia oxidizing microbe were different in different stages when the original broad-leaved forest degradation.The abundance of AOA of the original broadleaved fores in May,June,and October were significant lower than that in secondary broad-leaved forestt,but the result in August and September were contrary(P<0.05).The abundance of amoA gene of AOB of the original broad-leaved forest in May,and August is significant higher than the secondary broad-leaved forest,but the result in July September and October were contrary(P<0.05).The amoA gene abundance of AOA and AOB in the two forest types showed an inverted "N" pattern from May to October,and the highest and lowest values appeared in July and September or October respectily,there were significant differences among different months.In the whole growth season,the AOA abundance of amoA gene in the original broad-leaved forest and secondary broad-leaved forest were significantly higher than that of the abundance of AOB(AOA/AOB>1),which may be higher about between 1-2 levels.AOA/AOB in original broad-leaved forest is significant lower than that of the secondary broad-leaved forest in May,June and October,while they were reverse in July(P<0.05).The soil temperature,available P,water content and NO3--N,indicating that those soil physicochemical properties were the main factor affecting the amoA gene abundance of ammonia oxidizing microorganisms.