Microecological System Research Articles

Differences of fungal diversity and structure in rhizosphere of Fritillaria thunbergii from different provenances

To explore the mechanism of soil microbial ecology, the differences of fungal diversities in rhizosphere of different provenances of Fritillaria thunbergii were analyzed. The diversities and compositions of rhizo-fungi of the samples were analyzed by using DGGE and 454 pyrosequencing. DGGE results showed the Shannon index of Ninbo provenance planted in Ninbo was the highest one. And its dominant fungi were Ascomycota, Deuteromycota and Zygomycota. Except the same fungi, every provenance planted in Ninbo had its own special ones. From the 454 pyrosequencing, the fungal diversity in Panan producing was the highest which was similar with DGGE result. Among the ten phylum detected in its rhizosoil, Fungi_incertae_sedis, Ascomycota, Mucoromycotina, Basidiomycota and Chytridiomycota almost amounted to 90% of the whole community. The fungal types and amounts in Panan were more than those in Ninbo indicating the differences between producing areas and the advantage of macro genome sequencing. There were 10 phyla, 29 families, 28 genus and 159 species of fungi in Panan provenance, 6 phyla, 20 families, 19 genus, 136 species in Ninbo provenance, 8 phyla, 37 families, 47 genus, 289 species in Nantong provenance and 7 phyla, 25 families, 24 genus, 102 species in the bulk soil. Some genus such as Dothidea, Capnobotryella and Conidiobolus were only existed in Nantong provenance, while Pyrenochae- ta, Glomus and Pseudonectria were only in Panan provenance, which implied these species could grew because F. thunbergii influenced the existence of fungi. Experiments of provenance and producing area of F. thunbergii showed that the fungal diversity of indigenous provenance was higher than that of exotic provenance and each provenance had unique fungal species in the rhizosphere, which indicated that the diversity and structure was shaped cooperatively by the species and soil type. These fungal species are interacted with the soil-rhizhosphere-microbe microecological system, which in turn influence the growth of F. thunbergii.

Human Pharyngeal Microbiome May Play A Protective Role in Respiratory Tract Infections

The human pharyngeal microbiome, which resides at the juncture of digestive and respiratory tracts, may have an active role in the prevention of respiratory tract infections, similar to the actions of the intestinal microbiome against enteric infections. Recent studies have demonstrated that the pharyngeal microbiome comprises an abundance of bacterial species that interacts with the local epithelial and immune cells, and together, they form a unique micro-ecological system. Most of the microbial species in microbiomes are obligate symbionts constantly adapting to their unique surroundings. Indigenous commensal species are capable of both maintaining dominance and evoking host immune responses to eliminate invading species. Temporary damage to the pharyngeal microbiome due to the impaired local epithelia is also considered an important predisposing risk factor for infections. Therefore, reinforcement of microbiome homeostasis to prevent invasion of infection-prone species would provide a novel treatment strategy in addition to antibiotic treatment and vaccination. Hence continued research efforts on evaluating probiotic treatment and developing appropriate procedures are necessary to both prevent and treat respiratory infections.

Influence of Ionic Liquid 1- butyl-3-methylimidazolium Chloride on the Soil Micro-Ecological System

In order to evaluate the influence of ionic liquid 1- butyl-3-methylimidazolium chloride ([Bmim]Cl) on the soil micro-ecological system, the toxicity of [Bmim]Cl to soil microorganisms and its impact on soil physico-chemical properties were investigated. Three soil samples, which were taken from the rape land, nursery land and the broad bean land respectively, were used for this study. The toxicity test results show that the [Bmim]Cl inhibited the growth of soil microorganisms including bacteria and actinomycetes. This inhibition became stronger with the [Bmim]Cl concentration increasing. The EC50 of soil bacteria was close to that of the Vibrio fischeri, and the EC50 of soil actinomycetes was near to that of the Pseudokirchneriella subcapitata. The soil physico-chemical properties test results indicate that the organic mass and the soluble salts in soil increased with the increase of the [Bmim]Cl concentration. The [Bmim]Cl also caused the pH change in the soil micro-ecological system. It suggests that the ionic liquid [Bmim]Cl would influence the soil micro- ecological system by inhibiting the growth of soil microorganisms and altering the soil physico-chemical properties when it contaminated the soil system.

Advance in Research of Forest Carbon Cycling Under Climate Warming*

Greater attention has been paid to human-induced climate warming,resulting from the enhanced greenhouse gases,and its impacts on forest ecosystems. As an important component of the global carbon cycling,gaining a better understanding of the responses of soil carbon cycling processes to climate warming is critical for predicting the changes in terrestrial ecosystem carbon cycling in the future. This paper reviews the recent progress of the research on climate warming and the factors influencing soil carbon cycling,including soil respiration,microbes,litterfall input and decomposition,enzyme activity and carbon pool. Recently,the effects of climate warming on soil carbon cycling have aroused great concern,but there remains a fundamental uncertainty regarding the research results. To advance our understanding of how climate change influences the soil carbon cycling of forest ecosystem,further studies are needed to address multifactor experiments in the field and enhance the interaction between field studies and modeling approaches. Also,there is an urgent need to analyze the distribution and fate of carbon fluxes in rhizosphere microecological system under climate change. Ref 70

Effect of releasing cotton seedling by turn-over plastic film on micro-ecological system in plastic-mulched cotton field

对地膜棉翻膜放苗的棉田微生态效应研究表明，翻膜放苗地膜的有效覆盖度比打孔放苗增加30%～45%，增强了对棉田水温变化的影响，翻膜放苗可明显提高大行地温，且对提高和稳定小行地温也有良好的效应。放苗初期，小行土壤含水量略低于对照，有利于解决地膜棉易出现高脚苗旺长问题。翻膜放苗后加剧了土壤空隙中水汽的膨缩运动，大行土壤容重平均比对照降低0.12 g·cm^-3，土壤疏松，水、气、热较为协调，耕层土壤微环境得到改善，为增强根系活力和扩大吸收范围创造了条件。有效覆盖度的增加增强了覆盖的反光效应，有利于提高近地层光照强度和棉株制造光合产物的能力，并增大了苗期对蚜虫迁入的拒避作用。

Hepatic Circulation

Hepatic Circulation

A mathematical description of microecologic correlations

Due to the diversity of microbiological interrelations results of animal experiments concerning the effect of nutrition factors on the microecological system in the intestinal tract are often difficulty to interpret. In order to reveal deeper correlations multivariate statistical methods particularly the non-linear multiple regression analysis are tried to use. First results show that correlations between nutrition factors and microecological signs of the colon content can be depict by quadratic polynoms, whereas for biochemical signs also a linear dependence appears possible.