本文对曾经已发表过的一些东北产莎草科薹草属植物(Carex mongolica Baranov et Skvortzov,C.cobresiaeformis Baranov et Skvortzov,C.chelungkiangnica Baranov et Skvortzov,C.yingkiliensis Baranov et Skvortzov,C.komaroviana Bar...本文对曾经已发表过的一些东北产莎草科薹草属植物(Carex mongolica Baranov et Skvortzov,C.cobresiaeformis Baranov et Skvortzov,C.chelungkiangnica Baranov et Skvortzov,C.yingkiliensis Baranov et Skvortzov,C.komaroviana Baranov et Skvortzov)加以讨论修订,这些植物不应是新种,它们应该分别属于过去已发表过的种类:Carex lithopila Turcz.,C.gynocrates Wormskj.ex Dreier.,C.cinerascens Kaenth.,C.mollissima Christ ex Scheutz.C.angarae steud。展开更多
Biological characteristics of methane emission were compared among Oryza sativa, Panicum crus-galli andCyperus difformis grown on paddy soil. The order of the amounts of methane emitted was P. crus-galli > O. sativ...Biological characteristics of methane emission were compared among Oryza sativa, Panicum crus-galli andCyperus difformis grown on paddy soil. The order of the amounts of methane emitted was P. crus-galli > O. sativa >C. difformis, with the former two 11 and 8 times as much as that of the latter, respectively. And it was just opposite tothat of the methane-forming activities of roots of the three plants. The diurnal changes of methane emission of thethree plants were relatively consistent with valleys during 11:00-14:00 and midnight and peaks during 8:00-11: 00,14:00- 20:00 and about 5:00 early morning. The methanogenic activites in rhizospheric soils were higher than those innonrhizospheric soils with P. crus-galli and O. sativa, but not with C. difformis. The pathways of methane release ofP. crus-galli and O . sativa were probably through the top gaps near the junctions of nodal plate and leaf sheath, how-ever in C. difformistopgaps from which methane could escape into atmosphere were not found.展开更多
The response of plant leaf and root phenology and biomass in the Arctic to global change remains unclear due to the lack of synchronous measurements of above-and belowground parts.Our objective was to determine the ph...The response of plant leaf and root phenology and biomass in the Arctic to global change remains unclear due to the lack of synchronous measurements of above-and belowground parts.Our objective was to determine the phenological dynamics of the above-and belowground parts of Eriophorum vaginatum in the Arctic and its response to warming.We established a common garden located at Toolik Lake Field Station;tussocks of E.vaginatum from three locations,Coldfoot,Toolik Lake and Sagwon,were transplanted into the common garden.Control and warming treatments for E.vaginatum were set up at the Toolik Lake during the growing seasons of 2016 and 2017.Digital cameras,a handheld sensor and minirhizotrons were used to simultaneously observe leaf greenness,normalized difference vegetation index and root length dynamics,respectively.Leaf and root growth rates of E.vaginatum were asynchronous such that the timing of maximal leaf growth(mid-july)was about 28 days earlier than that of root growth.Warming of air temperature by 1°C delayed the timing of leaf senescence and thus prolonged the growing season,but the temperature increase had no significant effect on root phenology.The seasonal dynamics of leaf biomass were affected by air temperature,whereas root biomass was correlated with soil thaw depth.Therefore,we suggest that leaf and root components should be considered comprehensively when using carbon and nutrient cycle models,as above-and belowground productivity and functional traits may have a different response to climate warming.展开更多
文摘本文对曾经已发表过的一些东北产莎草科薹草属植物(Carex mongolica Baranov et Skvortzov,C.cobresiaeformis Baranov et Skvortzov,C.chelungkiangnica Baranov et Skvortzov,C.yingkiliensis Baranov et Skvortzov,C.komaroviana Baranov et Skvortzov)加以讨论修订,这些植物不应是新种,它们应该分别属于过去已发表过的种类:Carex lithopila Turcz.,C.gynocrates Wormskj.ex Dreier.,C.cinerascens Kaenth.,C.mollissima Christ ex Scheutz.C.angarae steud。
文摘Biological characteristics of methane emission were compared among Oryza sativa, Panicum crus-galli andCyperus difformis grown on paddy soil. The order of the amounts of methane emitted was P. crus-galli > O. sativa >C. difformis, with the former two 11 and 8 times as much as that of the latter, respectively. And it was just opposite tothat of the methane-forming activities of roots of the three plants. The diurnal changes of methane emission of thethree plants were relatively consistent with valleys during 11:00-14:00 and midnight and peaks during 8:00-11: 00,14:00- 20:00 and about 5:00 early morning. The methanogenic activites in rhizospheric soils were higher than those innonrhizospheric soils with P. crus-galli and O. sativa, but not with C. difformis. The pathways of methane release ofP. crus-galli and O . sativa were probably through the top gaps near the junctions of nodal plate and leaf sheath, how-ever in C. difformistopgaps from which methane could escape into atmosphere were not found.
基金the Office of Polar Programs(National Science Foundation)(1417763 to J.T.,1418010 to N.F.and 1417645 to M.L.M.).
文摘The response of plant leaf and root phenology and biomass in the Arctic to global change remains unclear due to the lack of synchronous measurements of above-and belowground parts.Our objective was to determine the phenological dynamics of the above-and belowground parts of Eriophorum vaginatum in the Arctic and its response to warming.We established a common garden located at Toolik Lake Field Station;tussocks of E.vaginatum from three locations,Coldfoot,Toolik Lake and Sagwon,were transplanted into the common garden.Control and warming treatments for E.vaginatum were set up at the Toolik Lake during the growing seasons of 2016 and 2017.Digital cameras,a handheld sensor and minirhizotrons were used to simultaneously observe leaf greenness,normalized difference vegetation index and root length dynamics,respectively.Leaf and root growth rates of E.vaginatum were asynchronous such that the timing of maximal leaf growth(mid-july)was about 28 days earlier than that of root growth.Warming of air temperature by 1°C delayed the timing of leaf senescence and thus prolonged the growing season,but the temperature increase had no significant effect on root phenology.The seasonal dynamics of leaf biomass were affected by air temperature,whereas root biomass was correlated with soil thaw depth.Therefore,we suggest that leaf and root components should be considered comprehensively when using carbon and nutrient cycle models,as above-and belowground productivity and functional traits may have a different response to climate warming.
