Absence of soil frost affects plant-soil interactions in temperate grasslands
Absence of soil frost affects plant-soil interactions in temperate grasslands
复制标题
DOI：
10.1007/s11104-013-1724-y
复制
发表时间：
2013-04
期刊：
影响因子：
4.9
通讯作者：
Jan Schuerings;C. Beierkuhnlein;Kerstin Grant;A. Jentsch;Andrey V Malyshev;J. Peñuelas;J. Sardans;J. Kreyling
中科院分区：
文献类型：
--
作者：
Jan Schuerings;C. Beierkuhnlein;Kerstin Grant;A. Jentsch;Andrey V Malyshev;J. Peñuelas;J. Sardans;J. Kreyling
背景和目的由于持续的气候变暖，冬季间歇性冻土预计将在温带大片地区消失。土壤霜冻的缺乏影响了植物与土壤的相互作用，需要进行更详细的研究。方法在温带草原连续两个冬季的田间试验中，利用地下电热线避免了冬季土壤霜冻。对两个冬季反复冻融循环的无霜区和参照区的土壤呼吸、土壤氮素有效性和植株表现(地上生物量、两个深度水平的根长、绿度、养分含量)进行了比较。土壤剖面上部10 cm土层的氮素有效性没有受到影响，这可能是由于冬季植物氮素积累量增加(+163%)、生长季植物氮素浓度增加(+18%)和生物量增加(+31.5%)所致。然而，根部向深层转移而不改变总根长可能是养分淋失的迹象。结论土壤变暖对碳循环的累积影响取决于土壤生物活性增加导致的冬季碳损失增加与生长季养分积累增加导致的植物生产力提高之间的平衡。
Background and aimsIntermittently frozen ground in winter is expected to disappear over large areas in the temperate zone due to ongoing climate warming. The lack of soil frost influences plant soil interactions and needs to be studied in more detail.MethodsWinter soil frost was avoided by belowground heating wires in a field experiment over two subsequent winters in a temperate grassland. Soil respiration, soil nitrogen availability and plant performance (aboveground biomass, root length at two depth levels, greenness, nutrient content) were compared between “no-frost” and reference plots which underwent repeated freeze-thaw cycles in both winters.ResultsSoil respiration increased in the “no-frost” treatment during the warming phase (+291 %). N-availability in the upper 10 cm of the soil profile was not affected, possibly due to increased plant N accumulation during winter (+163 %), increased plant N concentration (+18 %) and increased biomass production (+31.5 %) in the growing season. Translocation of roots into deeper soil layers without changes in total root length in response to the “no-frost” treatment, however, may be a sign of nutrient leaching.ConclusionsThe cumulative effect on carbon cycling due to warmer soils therefore depends on the balance between increased winter carbon loss due to higher soil biotic activity and enhanced plant productivity with higher nutrient accumulation in the growing season.