Understanding the underlying processes of how communities are structured remains a central question in community ecology. However, the mechanisms of the soil animal community are still unclear, especially for communit...Understanding the underlying processes of how communities are structured remains a central question in community ecology. However, the mechanisms of the soil animal community are still unclear, especially for communities on a small scale. To evaluate the relative roles of biotic interactions and environmental and spatial processes in a soil collembolan community, a field experiment was carried out on a small scale(50 m) in the farmland ecosystem of the Sanjiang Plain, Northeast China. In August and October, 2011, we took 100 samples each month in a 50 m × 50 m plot using a spatially delimited sampling design. Variation partitioning was used to quantify the relative contributions of the spatial and environmental variables. A null model was selected to test for the non-randomness pattern of species co-occurrence and body size in assemblages of collembolans and to test whether the pattern observed was the result of environmental or biotic processes that structured the community on a small scale. The results showed that large variance was accounted for by spatial variables(18.99% in August and 21.83% in October, both were significant). There were relatively lower effects of environmental variation(3.56% in August and 1.45% in October, neither was significant), while the soil water content, soil p H and soybean height explained a significant portion of the variance that was observed in the spatial pattern of the collembolan community. Furthermore, the null model revealed more co-occurrence than expected by chance, suggesting that collembolan communities had a non-random co-occurrence pattern in both August and October. Additionally, environmental niche overlap and the body size ratio of co-occurrence showed that interspecific competition was not influential in collembolan community structuring. Considering all of the results together, the contributions of spatial and environmental processes were stronger than biotic interactions in the small-scale structuring of a soil collembolan community.展开更多
Background:Accumulating evidence suggests that metabolic disorders,including type 2 diabetes mellitus(T2DM),can be treated with traditional Chinese medicine formulas,such as the Gegen Qinlian decoction(GQD).This study...Background:Accumulating evidence suggests that metabolic disorders,including type 2 diabetes mellitus(T2DM),can be treated with traditional Chinese medicine formulas,such as the Gegen Qinlian decoction(GQD).This study elucidates the mechanisms by which gut microbes mediate the anti-diabetic effects of GQD.Methods:We conducted a double-blind randomized clinical trial involving 120 untreated participants with T2DM.During the 12-week intervention,anthropometric measurements and diabetic traits were recorded every 4 weeks.Fecal microbiota and serum metabolites were measured before and after the intervention using 16S rDNA sequencing,liquid chromatography-mass spectrometry,and Bio-Plex panels.Results:Anti-diabetic effects were observed in the GQD group in the human trial.Specifically,glycated hemoglobin,fasting plasma glucose,and two-hour postprandial blood glucose levels were significantly lower in the GQD group than in the placebo group.Additionally,Faecalibacterium was significantly enriched in the GQD group,and the short-chain fatty acid levels were higher and the serum inflammation-associated marker levels were lower in the GQD group compared to the placebo group.Moreover,Faecalibacterium abundance negatively correlated with the levels of serum hemoglobin,fasting plasma glucose,and pro-inflammatory cytokines.Finally,the diabetes-alleviating effect of Faecalibacterium was confirmed by oral administration of Faecalibacterium prausnitzi(DSMZ 17677)in T2DMmousemodel.Conclusions:GQD improved type 2 diabetes primarily by modulating the abundance of Faecalibacterium in the gut microbiota,alleviating metabolic disorders and the inflammatory state.展开更多
基金Under the auspices of National Natural Science Foundation of China(No.41101049,41471037,41371072,41430857)University Nursing Program for Young Scholars with Creative Talents in Heilongjiang Province(No.UNPYSCT-2015054)+1 种基金Distinguished Young Scholar of Harbin Normal University(No.KGB201204)Excellent Youth Scholars of Northeast Institute of Geography and Agroecology,Chinese Academy of Sciences(No.DLSYQ13003)
文摘Understanding the underlying processes of how communities are structured remains a central question in community ecology. However, the mechanisms of the soil animal community are still unclear, especially for communities on a small scale. To evaluate the relative roles of biotic interactions and environmental and spatial processes in a soil collembolan community, a field experiment was carried out on a small scale(50 m) in the farmland ecosystem of the Sanjiang Plain, Northeast China. In August and October, 2011, we took 100 samples each month in a 50 m × 50 m plot using a spatially delimited sampling design. Variation partitioning was used to quantify the relative contributions of the spatial and environmental variables. A null model was selected to test for the non-randomness pattern of species co-occurrence and body size in assemblages of collembolans and to test whether the pattern observed was the result of environmental or biotic processes that structured the community on a small scale. The results showed that large variance was accounted for by spatial variables(18.99% in August and 21.83% in October, both were significant). There were relatively lower effects of environmental variation(3.56% in August and 1.45% in October, neither was significant), while the soil water content, soil p H and soybean height explained a significant portion of the variance that was observed in the spatial pattern of the collembolan community. Furthermore, the null model revealed more co-occurrence than expected by chance, suggesting that collembolan communities had a non-random co-occurrence pattern in both August and October. Additionally, environmental niche overlap and the body size ratio of co-occurrence showed that interspecific competition was not influential in collembolan community structuring. Considering all of the results together, the contributions of spatial and environmental processes were stronger than biotic interactions in the small-scale structuring of a soil collembolan community.
基金supported by the National Natural Science Foundation of China (Grants No.81430097,81973837,82004242,82274343 and 31771481)the Innovation Team and Talents Cultivation Program of National Administration of Traditional Chinese Medicine (Grant No.ZYYCXTD-D-202001).
文摘Background:Accumulating evidence suggests that metabolic disorders,including type 2 diabetes mellitus(T2DM),can be treated with traditional Chinese medicine formulas,such as the Gegen Qinlian decoction(GQD).This study elucidates the mechanisms by which gut microbes mediate the anti-diabetic effects of GQD.Methods:We conducted a double-blind randomized clinical trial involving 120 untreated participants with T2DM.During the 12-week intervention,anthropometric measurements and diabetic traits were recorded every 4 weeks.Fecal microbiota and serum metabolites were measured before and after the intervention using 16S rDNA sequencing,liquid chromatography-mass spectrometry,and Bio-Plex panels.Results:Anti-diabetic effects were observed in the GQD group in the human trial.Specifically,glycated hemoglobin,fasting plasma glucose,and two-hour postprandial blood glucose levels were significantly lower in the GQD group than in the placebo group.Additionally,Faecalibacterium was significantly enriched in the GQD group,and the short-chain fatty acid levels were higher and the serum inflammation-associated marker levels were lower in the GQD group compared to the placebo group.Moreover,Faecalibacterium abundance negatively correlated with the levels of serum hemoglobin,fasting plasma glucose,and pro-inflammatory cytokines.Finally,the diabetes-alleviating effect of Faecalibacterium was confirmed by oral administration of Faecalibacterium prausnitzi(DSMZ 17677)in T2DMmousemodel.Conclusions:GQD improved type 2 diabetes primarily by modulating the abundance of Faecalibacterium in the gut microbiota,alleviating metabolic disorders and the inflammatory state.
