Analysis Of Plant Nutrition Internal Cycle And Its Influencing Factor In Eucalyptus Plantation

The study of plant nutritional endo circulation,and its synergistic effect with soil fertility,soil microorganisms and so on in the continuous operation of Eucalyptus plantation provided theoretical and technological support for the continuous operation of Eucalyptus plantation.In this study,three locations where Mashan,Liangfeng Jiang and Xiaolin were selected as the research areas.Research objects that juvenile leaves,mature leaves,and senescent leaves of the sample trees were measured the nutrient element content and water-soluble nutrient element content,and between them relationship;hat to analysis the internal cycle of nutrition and the internal cycle of water-soluble nutrients of the Eucalyptus Plantation.The soil in the root area and the inter row were collected as the research objects.The objects were determination soil basic physicochemical properties and using Illumina Miseq determination soil microorganisms.The conducted were to analyze the effects of differences in soil physicochemical properties,soil bacteria,fungal communities on the nutrient endo cycle of Eucalyptus plantation plants.It’s findings are as follows:1.The transfer of N,P,K,Mg nutrient elements was from senescent leaves to tender leaves and mature leaves,Ca,Fe,Al,Mn,Si,B these seven nutrient elements increased as the leaves continue growing,and the content of Zn decreased with the growth and development of the leaves,but with an accumulation from mature leaves to senescent leaves.Mo content in the three plots showed a different trend with the growth and development of leaves.The reabsorption rate of N,P,K and Mg elements in juvenile leaves was higher than that in mature leaves.For Zn,only juvenile leaves are reabsorbed.The reabsorption rate of P element is greatly affected by the soil properties,and the reabsorption rate of juvenile and mature leaves is inconsistent with soil properties.2.The results showed that the water-soluble fractions contents of nitrogen,phosphorus,potassium,magnesium,and zinc gradually decreased with leaf growth,that of calcium,aluminum,manganese,boron,and silicon gradually increased with leaf growth,and that the water-soluble fractions contents of iron and molybdenum did not change linearly with leaf growth.The N,P,K,Mg,Ca,Al,Mn,Si,and B nutrient elements showed the same trend with the change of water-soluble content,while the Fe elements showed the difference with the change trend of water-soluble content.The proportion of the whole amount of water-soluble nutrient contents varied among juvenile,mature and senescent leaves,and the proportion did not correlate with nutrient transfer.3.Bacteria in the soil of Eucalyptus plantation belonged to 33 phyla 102 classes 192 orders 313 families 558 genera,and the dominant bacterial phyla were consistent among the three plots.The indicator bacteria in the soil of Eucalyptus plantation on Liangfeng Jiang were Candidatus＿Xiphinematobacter,Verrucomicrobia,Salinispora.The indicator bacteria in the soil of Eucalyptus plantation on Mashan were Betaproteobacteria,Burkholderiales,Burkholderiaceae,Firmicutes.And the indicator bacteria in the soil of Eucalyptus plantation on Xiaolin were Actinobacteria,Actinomycetales,Gammaproteobacteria,Mycobacteriaceae,and Mycobacterium.The fungal community on the soil of Eucalyptus plantation belonged to 14 phyla 35 classes84 orders 178 families 299 genera,and the dominant fungal phyla in the three plots were consistent.The indicator fungal in the soil of Eucalyptus plantation on Liangfeng Jiang were Sclerodermataceae,Scleroderma,Boletales,etc;The indicator fungal in the soil of Eucalyptus plantation on Mashan were Agaricales,Glomerellales,Plectosphaerellaceae,etc.The indicator fungal in the soil of Eucalyptus plantation on Xiaolin were Trechispora,Trechisporales,Hydnodontaceae et al.