红树林碳埋藏过程对海平面上升、气候变化和人类活动的响应

红树林具有很高的初级生产力和沉积速率,能够在沉积过程中埋藏封存大量有机碳,在全球碳循环中扮演着重要角色。本文总结有关红树林碳埋藏特征和沉积过程对气候变化、海平面上升和人类活动响应的相关文献研究。红树林土壤碳埋藏储量主要取决于红树林根系分布深度,碳埋藏速率则主要受沉积速率控制。全球变暖导致亚热带冬季低温事件减少,以及降雨量的增多,都会促进红树林扩张,有利于红树林碳埋藏。在短期内,海平面上升可以通过增加滩面沉积速率和有机碳含量的方式,达到保持或提高红树林碳埋藏速率的效果。但是从长期来看,不断增加的海平面上升速率会对泥沙供应较少或潮差较小地区的红树林造成严重威胁。人类的不合理活动则会造成红树林面积和碳埋藏储量的大幅减少。因此,为保护红树林并发挥其碳库潜力,应采取有效措施保证红树林沉积的物源供给,以维持红树林滩面高程增加速率,并在适宜地区进行人工红树林栽种。

Response of Carbon Sequestration in Mangroves to Sea Level Rise,Climate Change and Human Activities

Mangroves have high primary productivity and sedimentation rate.They can bury and store a large amount of organic carbon during the sedimentation process,and play an important role in the global carbon cycle.This article summarizes relevant literatures and studies on mangrove carbon burial characteristics and sedimentation processes in response to climate change,sea level rise,and human activities.The buried carbon reserves of mangrove soil are mainly determined by the distribution depth of mangrove roots,while the buried carbon rate is mainly controlled by the sedimentation rate.Global warming induced fewer cold weather events in subtropical and increased rainfall,which will promote the expansion of mangrove and mangrove carbon burial.In the short term,sea level rise can be dealt with by increasing the beach sedimentation rate and organic carbon content to achieve the effect of maintaining and increasing the mangrove carbon burial rate.But in the long run,the increasing rate of sea level rise will pose a serious threat to mangroves in areas with low sediment supplies or low tidal ranges.Irrational human activities will result in a significant reduction in mangrove area and carbon storage.Therefore,in order to protect mangroves and realize their carbon potential,effective measures should be taken to ensure the supply of mangrove sediment sources to maintain the increase rate of mangrove flat elevation and artificial mangrove planting in suitable areas.