Aims Foliar pH of terrestrial plants,a trait tightly associated with plant physiology and nutrient utilization,varies with plant functional types(PFTs)and environmental changes.However,it is yet unclear about the vari...Aims Foliar pH of terrestrial plants,a trait tightly associated with plant physiology and nutrient utilization,varies with plant functional types(PFTs)and environmental changes.However,it is yet unclear about the variation in foliar pH of aquatic plants,and the difference between aquatic and terrestrial plants.Methods Foliar pH,leaf carbon,nitrogen content of plants along the lakeshore zones and the environmental conditions(water or soil pH,water status)of the corresponding vegetation of three small plateau lakes were investigated,to determine the variation and potential influence factors of foliar pH at both PFT and community levels.Important Findings Foliar pH varied largely among aquatic plants,and across aquatic,helophytic and terrestrial plants.Floating-leaved macrophytes had more acidic foliage(pH=4.21±0.05)than emergent(5.71±0.07)and submerged macrophytes(5.82±0.06).Foliar pH of aquatic herbs(5.43±0.10)was lower than that of helophytic(6.12±0.07)and terrestrial herbs(5.74±0.05).Terrestrial herbs had significantly higher foliar pH than woody plants.The variation in foliar pH across PFTs may be mainly ascribed to leaf structure,light utilization and nutrient characteristics.Consistent with the pattern on PFT level,aquatic communities had more acidic foliage than terrestrial communities,which was mainly shaped by species composition,water status and environmental pH.This study documented the first-time foliar pH of aquatic plants,and comparison of foliar pH among various plant types at a landscape scale.Our results provide bases for further exploration of the underlying mechanism and its ecological significance for wetland ecosystems.展开更多
Forest edges have been well studied in temperate and tropical forests,but less so in open canopy forests.We investigated edge influence on plant species diversity and soil properties in sparse oak forest fragments.Dat...Forest edges have been well studied in temperate and tropical forests,but less so in open canopy forests.We investigated edge influence on plant species diversity and soil properties in sparse oak forest fragments.Data were collected along three transects from the edge to the interior of three small(under 10 ha)and three large(over 10 ha)oak forest fragments in Kermanshah Province,Iran.We measured herbaceous plants(<0.5 m in height)and soil attributes at 0(forest edge),25,50,100 and 150 m.We quantified species diversity using the Shannon index,used rarefaction to compare species richness between two different sizes of fragments and applied non-metric multidimensional scaling ordination to investigate the variation in species composition.We estimated the distance of edge influence using randomization tests.Generalized linear mixed models with post-hoc Tukey’s HSD tests were used to assess the effects of distance from edge and fragment size on diversity and soil properties.We found greater species richness,diversity and evenness at the edge of both small and large fragments and lower nitrogen and organic carbon at the edge compared to the interior of large fragments,with most changes within 50 m of the edge.Species composition,organic carbon and total nitrogen were significantly different between small and large fragments.Our findings of significant edge influence on herbaceous plants and soil properties in these sparse forests provide a significant contribution to the literature on edges,especially in relation to herbaceous plants.展开更多
基金This research was supported by the National Key Research and Development Program of China(2018YFC0507204)the National Natural Science Foundation of China(41473068,32001165).
文摘Aims Foliar pH of terrestrial plants,a trait tightly associated with plant physiology and nutrient utilization,varies with plant functional types(PFTs)and environmental changes.However,it is yet unclear about the variation in foliar pH of aquatic plants,and the difference between aquatic and terrestrial plants.Methods Foliar pH,leaf carbon,nitrogen content of plants along the lakeshore zones and the environmental conditions(water or soil pH,water status)of the corresponding vegetation of three small plateau lakes were investigated,to determine the variation and potential influence factors of foliar pH at both PFT and community levels.Important Findings Foliar pH varied largely among aquatic plants,and across aquatic,helophytic and terrestrial plants.Floating-leaved macrophytes had more acidic foliage(pH=4.21±0.05)than emergent(5.71±0.07)and submerged macrophytes(5.82±0.06).Foliar pH of aquatic herbs(5.43±0.10)was lower than that of helophytic(6.12±0.07)and terrestrial herbs(5.74±0.05).Terrestrial herbs had significantly higher foliar pH than woody plants.The variation in foliar pH across PFTs may be mainly ascribed to leaf structure,light utilization and nutrient characteristics.Consistent with the pattern on PFT level,aquatic communities had more acidic foliage than terrestrial communities,which was mainly shaped by species composition,water status and environmental pH.This study documented the first-time foliar pH of aquatic plants,and comparison of foliar pH among various plant types at a landscape scale.Our results provide bases for further exploration of the underlying mechanism and its ecological significance for wetland ecosystems.
基金financially supported by the vice chancellor for research and technology of Urmia University and received no external funding.
文摘Forest edges have been well studied in temperate and tropical forests,but less so in open canopy forests.We investigated edge influence on plant species diversity and soil properties in sparse oak forest fragments.Data were collected along three transects from the edge to the interior of three small(under 10 ha)and three large(over 10 ha)oak forest fragments in Kermanshah Province,Iran.We measured herbaceous plants(<0.5 m in height)and soil attributes at 0(forest edge),25,50,100 and 150 m.We quantified species diversity using the Shannon index,used rarefaction to compare species richness between two different sizes of fragments and applied non-metric multidimensional scaling ordination to investigate the variation in species composition.We estimated the distance of edge influence using randomization tests.Generalized linear mixed models with post-hoc Tukey’s HSD tests were used to assess the effects of distance from edge and fragment size on diversity and soil properties.We found greater species richness,diversity and evenness at the edge of both small and large fragments and lower nitrogen and organic carbon at the edge compared to the interior of large fragments,with most changes within 50 m of the edge.Species composition,organic carbon and total nitrogen were significantly different between small and large fragments.Our findings of significant edge influence on herbaceous plants and soil properties in these sparse forests provide a significant contribution to the literature on edges,especially in relation to herbaceous plants.
