Contrasting effects of nitrogen and phosphorus additions on fine root production and morphological traits of different plant functional types in an ombrotrophic peatland
Contrasting effects of nitrogen and phosphorus additions on fine root production and morphological traits of different plant functional types in an ombrotrophic peatland
复制标题
DOI：
10.1007/s11104-023-06087-3
复制
发表时间：
2023-05
期刊：
影响因子：
4.9
通讯作者：
Leming Ge;Cheng Chen;Tong Li;Z. Bu;Meng Wang
中科院分区：
文献类型：
--
作者：
Leming Ge;Cheng Chen;Tong Li;Z. Bu;Meng Wang
研究背景与目的细根形态特征的变化表明植物适应策略的转变。然而，目前还不清楚氮（N）和磷（P）沉积如何改变泥炭地细根适应策略，无论是在生长和非生长season.MethodsWe收集细根灌木和草本植物后，2年的N和P添加和测量的关键形态特征，以评估不同的适应策略。施氮条件下，磷通过降低细根长度（FRL）显著增加灌木细根产量（FRP），但与氮素配施时，这种作用减弱。无论氮添加率如何，磷添加都通过增加草本植物的FRL和细根直径（FRD）来显著增加FRP。施肥后，灌木和草本植物细根采取了不同的适应策略。灌木和草本植物的细根在非生长季节仍然增长，但只有灌木FRP显着下降后，N添加降低根组织密度（RTD.ConclusionShrub FRP更响应于N添加，而P添加对草本FRP有更强的影响。氮和磷的添加可能会导致转向对草本细根的“外包”策略，而灌木细根往往采取“快速”的保护策略下，磷添加。总的来说，施氮不利于灌木越冬。我们的研究结果可以促进对氮磷不平衡沉积条件下北方泥炭地细根适应性变化的理解。
Background and aimsChanges in morphological traits of fine roots indicate shift in adaptive strategies. However, it remains unclear how nitrogen (N) and phosphorus (P) depositions change fine root adaptive strategies in peatlands, both in the growing and non-growing seasons.MethodsWe collected fine roots from shrubs and herbaceous plants after 2-year N and P additions and measured key morphological traits to evaluate different adaptive strategies.ResultsDuring the growing season, P addition significantly increased shrub fine root production (FRP) by decreasing fine root length (FRL) under ambient N condition, while the effect was diminished when P was added in combination with N. Phosphorus addition significantly increased FRP by increasing FRL and fine root diameter (FRD) of herbaceous plants irrespective of N addition rate. Fine roots of shrub and herbaceous plants adopted contrasting adaptive strategies after fertilization. Fine roots of both shrub and herbaceous plants still grew in the non-growing season, but only shrub FRP was significantly decreased after N addition by decreasing root tissue density (RTD).ConclusionShrub FRP was more responsive to N addition whereas P addition had a stronger impact on herbaceous FRP. Nitrogen and P additions may have led to a shift towards the “outsourcing” strategy for herbaceous fine roots, whereas shrub fine roots tended to adopt the “fast” conservation strategy under P addition. Overall, N addition was disadvantageous to shrubs to survive cold winter. Our findings can advance the understanding of changes in fine root adaptation in northern peatlands under imbalanced N and P deposition.