The chemical properties and biological activities of soils were studied in the vicinity of the medieval settlement Podkumskoe-3 in the Kislovodsk basin(Northern Caucasus, Russia). Between the 5 th and 8 th centuries t...The chemical properties and biological activities of soils were studied in the vicinity of the medieval settlement Podkumskoe-3 in the Kislovodsk basin(Northern Caucasus, Russia). Between the 5 th and 8 th centuries this area was ploughed regularly, but it was then abandoned up to the present day. It has been established that past human activity leads to soil undergoing significant transformations in terms of microbial communities and enzyme activity, and that such changes are maintained over long periods. Long-term manuring in the middle of the first millennium AD led to an increase in organic carbon content and the accumulation of nitrate nitrogen. Soils of ancient abandoned fields are associated with increases in microbial biomass, number of saprotrophic bacteria, urease activity, and fungal mycelium biomass. The observed changes in the microbiological and biochemical properties of soil were conditioned by secondary anthropogenically induced succession after the abandonment of arable lands.展开更多
Soils from Poplar,Willow,Black locust plantations were compared to arable soil.Among five tested C cycle functional genes,three discriminated between treatments.Fungi contributed more than bacteria to theβ-glucosidas...Soils from Poplar,Willow,Black locust plantations were compared to arable soil.Among five tested C cycle functional genes,three discriminated between treatments.Fungi contributed more than bacteria to theβ-glucosidase enzyme activity.Fungalβ-glucosidase gene may be considered an indicator of increased C storage.Soil carbon sequestration is regulated by microbial extracellular enzymes.Insight into this process can be gained by studying the relationship between enzyme activity,soil organic carbon and microbial functional genes.The genetic potential of microorganisms to produce carbon cycling enzymes was evaluated in unmanaged plantations of Poplar,Willow,and Black locust,compared with a nearby arable soil.Bacterial and fungal functional genes encoding for cellulase,endoglucanase,endoxylanase andβ-glucosidase enzymes were quantified by real-time PCR.The abundance of three out of five genes differed between the treatments.The fungal gene encodingβ-glucosidase contributed to the corresponding enzyme activity more than the bacterial one,as evidenced by a positive correlation between gene abundance and enzyme activity(r=0.42).This gene exhibited a positive correlation with soil organic carbon content(r=0.42),with higher values in Willow(9×10^(2) gene copiesμL^(−1) and 1.4%SOC).These results suggest that the fungalβ-glucosidase gene abundance can be regarded as an indicator of increased carbon storage,similarly to the corresponding enzyme activity.The integrated analysis of soil carbon enzyme activities and DNA-based techniques enhanced our comprehension of carbon dynamics by revealing distinct contributions of microbial taxonomic groups to carbon accrual.展开更多
基金funded by the Russian Science Foundation(Grant No.17-78-10207)
文摘The chemical properties and biological activities of soils were studied in the vicinity of the medieval settlement Podkumskoe-3 in the Kislovodsk basin(Northern Caucasus, Russia). Between the 5 th and 8 th centuries this area was ploughed regularly, but it was then abandoned up to the present day. It has been established that past human activity leads to soil undergoing significant transformations in terms of microbial communities and enzyme activity, and that such changes are maintained over long periods. Long-term manuring in the middle of the first millennium AD led to an increase in organic carbon content and the accumulation of nitrate nitrogen. Soils of ancient abandoned fields are associated with increases in microbial biomass, number of saprotrophic bacteria, urease activity, and fungal mycelium biomass. The observed changes in the microbiological and biochemical properties of soil were conditioned by secondary anthropogenically induced succession after the abandonment of arable lands.
基金performed within the frame of CREA research facilities by using institutional resources and funds from the European Joint Programme(EJP SOIL)Project AGROECOseqC“AGROECOlogical strategies for an efficient functioning of plant-soil biota interactions to increase SOC sequestration,”European Union’s Horizon 2020 research and innovation program:Grant agreement No.862695.
文摘Soils from Poplar,Willow,Black locust plantations were compared to arable soil.Among five tested C cycle functional genes,three discriminated between treatments.Fungi contributed more than bacteria to theβ-glucosidase enzyme activity.Fungalβ-glucosidase gene may be considered an indicator of increased C storage.Soil carbon sequestration is regulated by microbial extracellular enzymes.Insight into this process can be gained by studying the relationship between enzyme activity,soil organic carbon and microbial functional genes.The genetic potential of microorganisms to produce carbon cycling enzymes was evaluated in unmanaged plantations of Poplar,Willow,and Black locust,compared with a nearby arable soil.Bacterial and fungal functional genes encoding for cellulase,endoglucanase,endoxylanase andβ-glucosidase enzymes were quantified by real-time PCR.The abundance of three out of five genes differed between the treatments.The fungal gene encodingβ-glucosidase contributed to the corresponding enzyme activity more than the bacterial one,as evidenced by a positive correlation between gene abundance and enzyme activity(r=0.42).This gene exhibited a positive correlation with soil organic carbon content(r=0.42),with higher values in Willow(9×10^(2) gene copiesμL^(−1) and 1.4%SOC).These results suggest that the fungalβ-glucosidase gene abundance can be regarded as an indicator of increased carbon storage,similarly to the corresponding enzyme activity.The integrated analysis of soil carbon enzyme activities and DNA-based techniques enhanced our comprehension of carbon dynamics by revealing distinct contributions of microbial taxonomic groups to carbon accrual.
