Effects Of Soil Mineral Particles On Propagation Of Microorganism And Decomposition Of Organic Materials

As soil inorganic nanoparticle (SINP) has some characteristics different from other macro-particle, micro-particle and atoms, it plays an important role in the controlling soil biochemistry reaction and has effect on soil microbe activity。This experiment was divided into two parts, the first part researched the effects of different rank and density soil particle on microorganism system. The result indicated: the propagation of microorganism related to different soil mineral particles and the density of nano-particle. Nano-rank particles significantly increased the propagation of microorganism, middle particles significantly increased the amounts of fungus, the biggest particles had no significant effects on microorganism. Otherwise the density of nanoparticles had different effects on microorganism: the high density and middle density of nanoparticle soil mineral particles all obviously increased the quantity of microorganism, the low density had no significant effects on microorganism.The second part studied the effects of soil mineral particles on the products during organic materials decomposing period by using incubation experiment of corn straw, tree leaves and deer manure. The results showed that: 1)nano-size soil mineral particles significantly increased the amount of water soluble organic material (WOM) and water soluble little molecular organic matters (WLOM) and water soluble humic acid(WAH)derived from woody organic materials; they had no significant effects on WOM and WLOM of herb organic materials, increased the amount of WAH in middle and latter period; during the decomposition of deer manure, nano-size soil mineral particles decreased WOM in former and middle-former period, significantly increased in middle period, for WLOM significantly decreased in former period, but increased in middle-latter period, only significantly decreased WHA in former period.2)the bigger mineral particles was different from nanoparticles: for woody organic materials, they had no significantly effects on WOM and WHA, for WLOM significantly decreased in former period, and increased in middle period; they significantly decreased WOM during the decomposition of deer manure, the effects on WLOM and WHA were concordance with nanoparticles.The different mineral particles had different effects on the products during the decomposition of organic materials which dealing with NaOH. 1) for woody organic materials, nanoparticles significantly decreased the amount of total alkali-soluble organic matters (NaAOM) in former period, but increased in the latter period, they significantly decreased the amount of alkali-soluble flumic acid (NaAFA) during all the decomposing period, significantly decreased the amount of alkali soluble humic acid (NaAHA) in former period; nanoparticles had no significant effects on NaAOM and NaAHA, significantly decreased NaAFA in the middle period during the decomposition of herb organic materials; nanoparticles significantly increased NaAOM and NaAHA derived from deer manure in middle and middle-latter period and decreased in the latter period, for NaAFA significantly decreased in the latter period, but increased in middle period. 2) The bigger size soil mineral particles significantly increased NaAOM of herb organic materials in middle-former and the latter period; significantly decreased NaAHA during all the decomposition; for woody organic materials, had no effect on NaAFA, significantly increased NaAHA after middle period; they increased the amount of NaAOM derived from deer manure in middle-former period and decreased in the former period, increased NaAFA in the middle period, decreased NaAHA s in former and middle period.Handling with Na₄P₂O₇, the result was: 1)nano-size soil mineral particles significantly decreased PAOM and PAFA of woody and herb organic materials, significantly decreased PAHA in the latter period of woody organic materials, significantly increased PAHA in the former and middle period, decreased in the middle-former and middle-latter period during the herb organic materials decomposing. Nanoparticles significantly increased PAOMå’ŒPAHA during the decomposition of deer munaur, for PAFA significantly decreased in the former period, increased in the all other period. 2) the bigger particles significantly decreased PAOM of herb organic materials in the latter period, and decreased in the middle-former period for woody organic materials; the bigger particles decreased PAFA of herb organic materials more significantly than nanoparticles; they decreased PAFA in the former period and after middle period, increased after the middle period during woody organic materials decomposing, increased PAHA in the former period. During the decomposition of deer manure, the bigger particles had the same effects on the products with nanoparticles.With the analysis of fourior transform infrared spectroscopy (FTIR), soil mineral particles decreased methyl, methylene,carbohydrate and carboxy group contents of WHA and AHA derived from woody and herb organic materials; soil mineral particles decreased methyl, methylene,carbohydrate contents of AHA, but increased carboxy group contents of AHA during deer manure decomposing period.