The aim of this study is to examine seasonal changes in Cu and Co concentrations of three plant species for monitoring the effects of pollution in Elazig,Turkey.For this purpose,the leaves of the Pinus nigra L.,Cedrus...The aim of this study is to examine seasonal changes in Cu and Co concentrations of three plant species for monitoring the effects of pollution in Elazig,Turkey.For this purpose,the leaves of the Pinus nigra L.,Cedrus libani and Cupressus arizonica together with soil samples were collected from different points depending on traffic intensity,nearness the city center and cement factory as well as control location during different months of the year.Flame atomic absorption spectrophotometer(FAAS) was used for measurement of the metals in clear digests after the dry ashing method.Copper and Co concentrations were in the ranges from 1.3to 2.6mg.kg-1 and<LOD to 0.26mg.kg-1 for Pinus nigra L.,1.2to 4.7mg.kg-1 and<LOD to 0.41mg.kg-1 for Cedrus libani and 1.5to 4.8mg.kg-1 and<LOD to 0.42mg.kg-1 for Cupressus arizonica,respectively.The levels observed for Cu and Co in the soil ranged from 12to 38mg.kg-1 and 6.0to 17mg.kg-1,respectively.展开更多
Two varieties of Bouteloua aristidoides have been recognized,the widespread var.aristidoides and the more narrowly distributed var.arizonica.The two varieties differ in inflorescence form even more than that seen betw...Two varieties of Bouteloua aristidoides have been recognized,the widespread var.aristidoides and the more narrowly distributed var.arizonica.The two varieties differ in inflorescence form even more than that seen between many other closely related species of Bouteloua.We therefore asked whether these taxa might be better regarded as distinct species.A total of 93 vouchers were studied by using morphometry(principal components analysis and statistical tests),leaf micromorphology,ancestral state reconstruction,and/or molecular(ITS,trnC-rpoB and trnT-L-F)phylogenetic analyses.Except from the ITS tree,all results supported elevation of B.aristidoides var.arizonica to the rank of species,thus the new combination Bouteloua arizonica(M.E.Jones)L.F.Cuellar&Columbus comb.nov.et stat.nov.,is proposed.Chloroplast and combined chloroplast-nuclear molecular trees depicted var.arizonica as monophyletic(even in sympatric populations with var.aristidoides)and reveals phylogenetic structure within var.aristidoides for which the presence of new undescribed varieties of B.aristidoides(different from B.arizonica)is addressed.B.arizonica differs from B.aristidoides in having fewer branches per inflorescence,a bigger branch with more spikelets,and a shorter branch extension.Scanning electron microscopy revealed the presence of papillae on leaves of B.arizonica as a clear synapomorphy.Growing mature plants of B.arizonica from seeds in a greenhouse revealed a strong cleistogamous nature for this species for which gene flow in sympatric populations with B.aristidoides seems unlikely.A taxonomic treatment and distribution map for identification of B.arizonica is provided.展开更多
We report here a damping-off disease occurring at the seedling stage of the grass Festuca arizonica (Arizona fescue) that is caused by the soil-borne fungal pathogen Rhizoctonia solani.
We report here a damping-off disease occurring at the seedling stage, resulting in severe loss of the seedling stands caused by an important soil-borne fungal pathogen, Fusarium oxysporum. Endophyte-infected plants ap...We report here a damping-off disease occurring at the seedling stage, resulting in severe loss of the seedling stands caused by an important soil-borne fungal pathogen, Fusarium oxysporum. Endophyte-infected plants appear to be more resistant to the damping-off disease than uninfected plants.展开更多
The city of Tehran, like many polluted metropolises of the world, has higher emissions of greenhouse gases than other cities in Iran, due to heavy consumption of fossil fuel and landuse changes. To estimate carbon seq...The city of Tehran, like many polluted metropolises of the world, has higher emissions of greenhouse gases than other cities in Iran, due to heavy consumption of fossil fuel and landuse changes. To estimate carbon sequestration in two 40 year-old stands of plantedCupressus arizonica andFraxinus rotundifolia in degraded lands surrounding Tehran , sampling of above- and below- ground biomass, soil （at two depths of 0-15 and 15-30 cm）, and leaf litter was done by systematic random sampling. The total carbon stocks ofC. arizonica and F. rotundifolia stands were respectively 328.20 and 150.69 Mg·ha-1. The aboveground biomass with 233.16（71%） Mg·ha-1 inC. arizonica and 88.16 （58.50%） Mg·ha-1 inF. rotundifolia contributed the most shares to carbon sequestration. The diameter at breast height, total height, basal area, total volume, and biomass ofC. arizonica were significantly （p 〈0.01） higher than those ofF. rotundifolia. Also the depth of 0-30 cm of soil contributed between 18.29 % and 32.15 % of total ecosystem carbon, respectively. The economic value of carbon sequestration in the two stands in 2011 was calculated at 3.5 and 2.5 million dollars, respectively. Our results indicate that afforestation of the degraded land surrounding Tehran would sequester more carbon than would continuously degraded land, the current status quo. These stands can absorb atmospheric CO2at different rates, thus tree species selection and stand development should be considered in planning future afforestation projects.展开更多
文摘The aim of this study is to examine seasonal changes in Cu and Co concentrations of three plant species for monitoring the effects of pollution in Elazig,Turkey.For this purpose,the leaves of the Pinus nigra L.,Cedrus libani and Cupressus arizonica together with soil samples were collected from different points depending on traffic intensity,nearness the city center and cement factory as well as control location during different months of the year.Flame atomic absorption spectrophotometer(FAAS) was used for measurement of the metals in clear digests after the dry ashing method.Copper and Co concentrations were in the ranges from 1.3to 2.6mg.kg-1 and<LOD to 0.26mg.kg-1 for Pinus nigra L.,1.2to 4.7mg.kg-1 and<LOD to 0.41mg.kg-1 for Cedrus libani and 1.5to 4.8mg.kg-1 and<LOD to 0.42mg.kg-1 for Cupressus arizonica,respectively.The levels observed for Cu and Co in the soil ranged from 12to 38mg.kg-1 and 6.0to 17mg.kg-1,respectively.
基金The authors acknowledge to the Consejo Nacional de Ciencia y Tecnologia(Mexico)for its support to Luis Fernando Cuellar-Garrido with the master's degree scholarship 615539。
文摘Two varieties of Bouteloua aristidoides have been recognized,the widespread var.aristidoides and the more narrowly distributed var.arizonica.The two varieties differ in inflorescence form even more than that seen between many other closely related species of Bouteloua.We therefore asked whether these taxa might be better regarded as distinct species.A total of 93 vouchers were studied by using morphometry(principal components analysis and statistical tests),leaf micromorphology,ancestral state reconstruction,and/or molecular(ITS,trnC-rpoB and trnT-L-F)phylogenetic analyses.Except from the ITS tree,all results supported elevation of B.aristidoides var.arizonica to the rank of species,thus the new combination Bouteloua arizonica(M.E.Jones)L.F.Cuellar&Columbus comb.nov.et stat.nov.,is proposed.Chloroplast and combined chloroplast-nuclear molecular trees depicted var.arizonica as monophyletic(even in sympatric populations with var.aristidoides)and reveals phylogenetic structure within var.aristidoides for which the presence of new undescribed varieties of B.aristidoides(different from B.arizonica)is addressed.B.arizonica differs from B.aristidoides in having fewer branches per inflorescence,a bigger branch with more spikelets,and a shorter branch extension.Scanning electron microscopy revealed the presence of papillae on leaves of B.arizonica as a clear synapomorphy.Growing mature plants of B.arizonica from seeds in a greenhouse revealed a strong cleistogamous nature for this species for which gene flow in sympatric populations with B.aristidoides seems unlikely.A taxonomic treatment and distribution map for identification of B.arizonica is provided.
文摘We report here a damping-off disease occurring at the seedling stage of the grass Festuca arizonica (Arizona fescue) that is caused by the soil-borne fungal pathogen Rhizoctonia solani.
文摘We report here a damping-off disease occurring at the seedling stage, resulting in severe loss of the seedling stands caused by an important soil-borne fungal pathogen, Fusarium oxysporum. Endophyte-infected plants appear to be more resistant to the damping-off disease than uninfected plants.
文摘The city of Tehran, like many polluted metropolises of the world, has higher emissions of greenhouse gases than other cities in Iran, due to heavy consumption of fossil fuel and landuse changes. To estimate carbon sequestration in two 40 year-old stands of plantedCupressus arizonica andFraxinus rotundifolia in degraded lands surrounding Tehran , sampling of above- and below- ground biomass, soil （at two depths of 0-15 and 15-30 cm）, and leaf litter was done by systematic random sampling. The total carbon stocks ofC. arizonica and F. rotundifolia stands were respectively 328.20 and 150.69 Mg·ha-1. The aboveground biomass with 233.16（71%） Mg·ha-1 inC. arizonica and 88.16 （58.50%） Mg·ha-1 inF. rotundifolia contributed the most shares to carbon sequestration. The diameter at breast height, total height, basal area, total volume, and biomass ofC. arizonica were significantly （p 〈0.01） higher than those ofF. rotundifolia. Also the depth of 0-30 cm of soil contributed between 18.29 % and 32.15 % of total ecosystem carbon, respectively. The economic value of carbon sequestration in the two stands in 2011 was calculated at 3.5 and 2.5 million dollars, respectively. Our results indicate that afforestation of the degraded land surrounding Tehran would sequester more carbon than would continuously degraded land, the current status quo. These stands can absorb atmospheric CO2at different rates, thus tree species selection and stand development should be considered in planning future afforestation projects.
