[Effects of reductive soil disinfestation and organic fertilizer application on microbial community stability in a facility vegetable soil].

Reductive soil disinfestation (RSD) is an effective method for remediating degraded facility vegetable soils. However, the effectiveness of RSD using green manure as a carbon source in the field has not yet been clarified. We investigated the effects of RSD and organic fertilizer application on soil microbial community composition, diversity, and stability in a degraded facility vegetable soil.

Denitrification process of root nodule endophyte .

To examine the characteristic of denitrification in , a symbiotic nitrogen-fixing microbe associated with non-leguminous plants, and its role as a NO source or sink, root nodule endophyte was isolated using sectioning method, which was then purely cultured to investigate the denitrification process under NO addition. The results showed that after addition of NO to the medium under anaerobic condition, the concentration of NO decreased with time, while the concentrations of NO and NO initially increased and then decreased over time. Key denitrification genes and nitrogenase gene were detected at 26 h, 54 h and 98 h during incubation.

[Effects of Feedstock Material and Pyrolysis Temperature on Dissolved Organic Matter in Biochars].

The aim of this study was to investigate the effects of feedstock material and pyrolysis temperature on the content and spectral properties of dissolved organic matter(DOM) in biochars. Biochars were produced from the pyrolysis of rice straw and litter at three temperatures(350, 500, and 650℃). The results showed that the pH values of the two biochars with pyrolysis temperature increases were improved from 8.

[Analysis of the Traits of Nitrogen Metabolism Pathways for Several Forest Soils in Eastern China].

Nitrogen metabolism pathways mediated by microorganisms play an important role in maintaining the structure and functional stability of soil ecosystems. Clarifying the relationships between microbial communities and nitrogen metabolism pathways can expand our understanding of nitrogen metabolism pathways at a microscopic level. However, the horizontal gene transfer of microorganisms means that taxonomy-based methods cannot be easily applied.

[Effects of litter removal and nitrogen addition on carbon and nitrogen in different soil fractions in a subtropical broad-leaved forest.].

The increasing nitrogen deposition due to human activities has impacted forest ecosystems to a large extent. The organic carbon and nitrogen released from decomposing litters play an important role in the formation, stability and transformation of soil organic carbon and nitrogen. We collected soil samples from a subtropical evergreen broadleaved forest experiment with nitrogen deposition [control (0), LN (75 kg·hm·a), HN (150 kg·hm·a)] and litter control (litter retained and litter removal) for eight years.

[Effects of biochar addition on the mineralization of native soil organic carbon in Cunninghamia lanceolata plantation.].

Effects of addition of different biochars on soil organic carbon (SOC) mineralization were studied by the C-labelling technique for a better understanding of biomass resource utilization and carbon sequestration in subtropical Chinese fir (Cunninghamia lanceolata) plantation. An incubation experiment under 25 ℃ was performed over a period of 112 days to address how different biochar addition would affect the mineralization of native SOC. Biochars were produced from Schimasuperba or C.

[Effects of water-soluble organic matter and residue of litter on nitrogen transformation in subtropical forest soil.].

An incubation experiment was carried out with the addition of litter filtrate, litter residue and alanine at 25 ℃ for 36 days under 60% and 90%WHC (water holding capacity) conditions. The results showed that alanine was rapidly mineralized in soil, and soil NH-N content significantly increased by 5.4%-44.

[Effects of L-methionine on nitrification and N2O emission in subtropical forest soil].

The objective of this study was to investigate the influence of L-methionine on nitrification and nitrous oxide emission in a red soil under laboratory incubation experiments. A subtropical broad-leaved forest soil sample was collected from Wanmulin natural reserve in Fujian Province, Southeast China. Five treatments were carried out with three replications, i.

[Soil microbial community structure of two types of forests in the mid-subtropics of China].

Soil microbial community structures were analyzed by biomarker method of phospholipid fatty acid (PLFA) for a natural forest dominated by Castanopsis fabri (CF) and an adjacent plantation of Cunninghamia lanceolata (CL) in the mid-subtropics of China. The results showed that the amounts of total PLFAs, bacterial PLFAs, fungal PLFAs, gram-positive bacterial PLFAs and gramnegative bacterial PLFAs in the 0-10 cm soil layer were higher than in the 10-20 cm soil layer, and each type of PLFAs in CF were higher than in CL. In either soil layer of the two forest types, the contents of bacterial PLFAs were significantly higher than those of fungal PLFAs.

[Organic carbon decomposition rate in different soil types].

With incubation experiment, this paper studied the decomposition rate of organic carbon in black soil, fluvo-aquic soil, and red soil. It was shown that these three soil types had significantly different decomposition rate constant of organic carbon (P < 0.05 ), with the corresponding value being 2.

Relationship between light and heavy fractions of organic matter for several agricultural soils in China.

Although numerous studies about the nature and turnover of soil organic matter(SOM) in light and heavy fractions(LFOM and HFOM, respectively) have been made, little information is available in relation to the relationship between LFOM and HFOM, and no attempts have been made to quantify a general relationship between LFOM and HFOM for agricultural soils under field condition. Our hypothesis is there may be an inherent relationship between LFOM and HFOM for agricultural soils under certain unaltered management practices for a long period, to this end, we therefore studied typically soils taken from different parts in China by using a simple density fractionation procedure. The results indicated that LFOM was positively correlated with LFOM/HFOM ratio for three typical soils.