In the Argentine Puna,a particular type of wetlands called vegas are considered unique,as they are the main biodiversity hotspots in this arid high-elevation environment.Also,they provide essential ecosystem services....In the Argentine Puna,a particular type of wetlands called vegas are considered unique,as they are the main biodiversity hotspots in this arid high-elevation environment.Also,they provide essential ecosystem services.Despite their ecological significance,these ecosystems remain poorly studied.Particularly soil mesofauna,which play critical roles in nutrient cycling and organic matter dynamics,remain to be explored.We investigated the composition,abundance,and richness of taxa and feeding guilds of soil mesofauna communities across 10 vegas.These wetlands were distributed along an environmental gradient,in an elevation range of 3323-4748 m a.s.l.,where we analysed soil properties and plant communities.We collected a total of 5239 invertebrates,from which Acari was the most abundant group,followed by Collembola.Regarding feeding guilds,detritivores and predators dominated soil mesofauna communities.Variability in taxa abundance and richness was strongly influenced by local soil properties,such as organic matter,carbon-to-nitrogen ratio,and phosphorus content,as well as plant community attributes,particularly cushion plant cover.However,no soil or vegetation variables explained the differences in taxa identity across vegas.These findings highlight the critical role of local heterogeneity in shaping soil mesofauna communities and provide the first insights into these understudied ecosystems.展开更多
Under warming soil respiration was higher,but soil microbial biomass was lower.Warming effect on soil respiration was higher in soil from the highest elevation.Soil respiration was higher in soil with higher soil carb...Under warming soil respiration was higher,but soil microbial biomass was lower.Warming effect on soil respiration was higher in soil from the highest elevation.Soil respiration was higher in soil with higher soil carbon content.Warming increased biomass-specific respiration and enzyme activity.The Q_(10) did not differ among soils from different elevations.Global warming is expected to increase the rate of soil carbon(C)efflux through enhanced soil microbial processes,mainly in systems,such as high elevation wetlands,storing large quantities of soil organic C.Here,we assessed the impact of experimental warming on respiration and microbial communities of high Andean wetland soils of the Puna region located at three different elevations(3793,3862,4206 m a.s.l.).We incubated soils at 10℃ and 25℃ for 68 days and measured the soil respiration rate and its temperature sensitivity(Q_(10)).Furthermore,we measured biomass and composition and enzymatic activity of soil microbial communities,and initial and final soil C content.Although warming increased soil respiration rates,with more pronounced effect in soils sampled from 4206 m a.s.l.,Q_(10) did not differ between elevations.Soil C content was higher at the highest elevation.Soil microbial biomass,but not enzymatic activity,was lower for warmed soil samples.However,the biomass-specific respiration and biomass-specific enzymatic activity were higher under warming,and in soil from the highest elevation wetland.These results suggest that,in the short-term,warming could stimulate resource allocation to respiration rather than microbial growth,probably related to a reduction in the microbial carbon use efficiency.Simultaneously,soils with higher soil C concentrations could release more CO_(2),despite the similar Q_(10) in the different wetlands.Overall,the soil of these high Andean wetlands could become C sources instead of C sinks,in view of forecasted increasing temperatures,with C-losses at regional scale.展开更多
基金supported by FONCYT grants(PICT 2016-2173,PICT 2018-04228).
文摘In the Argentine Puna,a particular type of wetlands called vegas are considered unique,as they are the main biodiversity hotspots in this arid high-elevation environment.Also,they provide essential ecosystem services.Despite their ecological significance,these ecosystems remain poorly studied.Particularly soil mesofauna,which play critical roles in nutrient cycling and organic matter dynamics,remain to be explored.We investigated the composition,abundance,and richness of taxa and feeding guilds of soil mesofauna communities across 10 vegas.These wetlands were distributed along an environmental gradient,in an elevation range of 3323-4748 m a.s.l.,where we analysed soil properties and plant communities.We collected a total of 5239 invertebrates,from which Acari was the most abundant group,followed by Collembola.Regarding feeding guilds,detritivores and predators dominated soil mesofauna communities.Variability in taxa abundance and richness was strongly influenced by local soil properties,such as organic matter,carbon-to-nitrogen ratio,and phosphorus content,as well as plant community attributes,particularly cushion plant cover.However,no soil or vegetation variables explained the differences in taxa identity across vegas.These findings highlight the critical role of local heterogeneity in shaping soil mesofauna communities and provide the first insights into these understudied ecosystems.
基金supported by FONCYT(Grant Nos.PICT 2016-2173,PICT 2018-04228)。
文摘Under warming soil respiration was higher,but soil microbial biomass was lower.Warming effect on soil respiration was higher in soil from the highest elevation.Soil respiration was higher in soil with higher soil carbon content.Warming increased biomass-specific respiration and enzyme activity.The Q_(10) did not differ among soils from different elevations.Global warming is expected to increase the rate of soil carbon(C)efflux through enhanced soil microbial processes,mainly in systems,such as high elevation wetlands,storing large quantities of soil organic C.Here,we assessed the impact of experimental warming on respiration and microbial communities of high Andean wetland soils of the Puna region located at three different elevations(3793,3862,4206 m a.s.l.).We incubated soils at 10℃ and 25℃ for 68 days and measured the soil respiration rate and its temperature sensitivity(Q_(10)).Furthermore,we measured biomass and composition and enzymatic activity of soil microbial communities,and initial and final soil C content.Although warming increased soil respiration rates,with more pronounced effect in soils sampled from 4206 m a.s.l.,Q_(10) did not differ between elevations.Soil C content was higher at the highest elevation.Soil microbial biomass,but not enzymatic activity,was lower for warmed soil samples.However,the biomass-specific respiration and biomass-specific enzymatic activity were higher under warming,and in soil from the highest elevation wetland.These results suggest that,in the short-term,warming could stimulate resource allocation to respiration rather than microbial growth,probably related to a reduction in the microbial carbon use efficiency.Simultaneously,soils with higher soil C concentrations could release more CO_(2),despite the similar Q_(10) in the different wetlands.Overall,the soil of these high Andean wetlands could become C sources instead of C sinks,in view of forecasted increasing temperatures,with C-losses at regional scale.
