大兴安岭多年冻土区泥炭地中8种植物叶片凋落物的元素含量特征

Characteristics of Element Contents of Leaf Litters of 8 Plant Species in Peatlands in Permafrost Regions of Daxing'an Mountains

2019年9月上旬,在大兴安岭地区漠河市图强镇连续性多年冻土区和新林区不连续性多年冻土区的泥炭地中,采集了落叶灌木、常绿灌木、草本植物和藓类植物功能群的柴桦(Betula fruticosa)、笃斯越橘(Vaccinium uliginosum)、狭叶杜香(Ledum palustre)、甸杜(Chamaedaphne calyculata)、小叶杜鹃(Rhododendron capitatum)、玉簪薹草(Carex globularis)、粗叶泥炭藓(Sphagnum squarrosum)和真藓(Bryum argenteum)的叶片凋落物样品,测定各种植物叶片凋落物中的碳、氮、磷、钾、钠、钙、镁、锰、铝和铁元素含量以及碳、氮同位素自然丰度(δ^(13)C、δ^(15)N)值。研究结果表明,图强镇连续性多年冻土区与新林区不连续性多年冻土区泥炭地中的狭叶杜香、甸杜、小叶杜鹃(常绿灌木)和粗叶泥炭藓、真藓(藓类植物)叶片凋落物的总有机碳含量相当,图强镇泥炭地中的柴桦、笃斯越橘(落叶灌木)和玉簪薹草(草本植物)叶片凋落物的总有机碳含量显著小于新林区泥炭地中的相同植物;图强镇泥炭地中的柴桦、笃斯越橘(落叶灌木)和粗叶泥炭藓、真藓(藓类植物)叶片凋落物的全氮含量分别显著大于新林区泥炭地中的相同植物,图强镇与新林区泥炭地中的其它4种植物叶片凋落物的全氮含量相当;图强镇泥炭地中的柴桦、小叶杜鹃叶片凋落物的全磷含量显著大于新林区泥炭地中的相同植物,图强镇泥炭地中的笃斯越橘、甸杜叶片凋落物的全磷含量显著小于新林区泥炭地中的相同植物,图强镇与新林区泥炭地中的其它4种植物叶片凋落物的全磷含量相当;总体上,新林区泥炭地中的8种植物叶片凋落物的碳氮比都明显大于图强镇泥炭地中的同一种植物,而其氮磷比都明显小于图强镇泥炭地中的同一种植物,图强镇和新林区泥炭地中的玉簪薹草叶片凋落物的碳氮比、碳磷比和氮磷比都明显大于其它功能群的植物;图强镇和新林区泥炭地中藓类植物凋落物的钠元素含量、铁元素含量、铝元素含量都远大于其它7种植物,常绿灌木和落叶灌木植物叶片凋落物的钾元素含量、镁元素含量、锰元素含量、钙元素含量都偏大,玉簪薹草的镁元素含量、锰元素含量、钙元素含量相对都最小;氮同位素自然丰度(δ^(15)N)对植物叶片凋落物的总有机碳含量、全氮含量、全磷含量及其比值的解释度最高达47.7%。

In early September 2019,the leaf litter samples of Betula fruticosa,Vaccinium uliginosum,Ledum palustre,Chamaedaphne calyculata,Rhododendron capitatum,Carex globularis,Sphagnum squarrosum,and Bryum argenteum were collected to determine the contents of carbon,nitrogen,phosphorus,potassium,sodium,calcium,magnesium,manganese,aluminum,and iron as well as the natural abundance of carbon and nitrogen isotopes(δ^(13)C,δ^(15)N)in the leaf litters of various plants.The results showed that total organic carbon contents of leaf litters of Ledum palustre,Chamaedaphne calyculata,Rhododendron capitatum(evergreen shrubs)and Sphagnum squarrosum,Bryum argenteum(mosses)in the peatlands of continuous permafrost zone in Tuqiang town were similar with those in the peatlands of discontinuous permafrost zone in Xinlin region;total organic carbon contents of leaf litters of Betula fruticosa,Vaccinium uliginosum(deciduous shrubs)and Carex globularis(herbs)in the peatlands of Tuqiang town were significantly less than those in the peatlands of Xinlin region;total nitrogen contents of leaf litters of Betula fruticosa,Vaccinium uliginosum and Sphagnum squarrosum,Bryum argenteum in the peatlands of Tuqiang town were significantly greater than those in the peatlands of Xinlin region,respectively,and the total nitrogen contents of leaf litters of the other four plants in the peatlands of Tuqiang town and Xinlin region were similar;total phosphorus contents of the leaf litters of Betula fruticosa and Rhododendron capitatum in the peatland of Tuqiang town was significantly greater than those in the peatland of Xinlin region,total phosphorus contents of leaf litters of Vaccinium uliginosum and Chamaedaphne calyculata in the peatland of Tuqiang town were significantly less than those in the peatland of Xinlin region,and total phosphorus contents of leaf litters of other 4 plants in the peatland of Tuqiang town and Xinlin region were similar;in general,the ratios of carbon content to nitrogen content of the leaf litters of the eight plants in the peatland of Xinlin region weree significantly greater than those in the peatland of Tuqiang town,the ratios of nitrogen content to phosphorus content were significantly less than those in the peatland of Tuqiang town,and the ratios of carbon content to nitrogen content,the ratios of carbon content to phosphorus content,and the ratios of nitrogen content to phosphorus content of leaf litters of Carex globularis in the peatland of Tuqiang town and Xinlin region were significantly greater than those of the other functional groups;the contents of sodium,iron,and aluminum of leaf litters of Sphagnum squarrosum and Bryum argenteum in the peatland of Tuqiang town and Xinlin region were much greater than those of the other seven plants;the contents of sodium,iron,and aluminum of leaf litters of Sphagnum squarrosum and Bryum argenteum in the peatlands of Tuqiang town and Xinlin region were much higher than those of the other seven species;the contents of potassium,magnesium,manganese,and calcium of leaf litters of evergreen shrubs and deciduous shrubs were larger,and the contents of magnesium,manganese and calcium of leaf litters of Carex globularis were the smallest;the maximum of interpretation of the contents of total organic carbon,total nitrogen,total phosphorus and their ratios of leaf litters byδ^(15)N was 47.7%.