湖泊湿地碳汇功能形成机制及碳储量评估方法研究进展

Research Progress on the Formation Mechanisms of Carbon Sink Functions and Carbon Storage Assessment Methods in Lake Wetlands

摘要: 湖泊湿地是陆地生态系统与水域生态系统相互作用最强烈的生态交错带，在区域碳循环和全球气候调节中具有重要作用。与森林、草地等典型陆地生态系统相比，湖泊湿地长期处于水分饱和或季节性淹水状态，低氧环境能够抑制有机质分解，促进植物残体、悬浮颗粒有机碳和沉积物有机碳的长期保存，从而形成重要的碳汇功能。近年来，随着“双碳”目标和湿地保护修复工作的推进，湖泊湿地碳固定、碳储量和碳埋藏速率的准确评估逐渐成为湿地生态学和碳循环研究的热点。已有研究表明，湖泊和水库沉积物有机碳埋藏是内陆水体碳循环的重要组成部分，且湖泊沉积物在长期尺度上能够将有机碳移出短期生物圈–大气碳循环。全球湖泊和水库有机碳埋藏研究也指出，内陆水体虽然面积有限，但其沉积碳汇功能不容忽视。本文从湖泊湿地碳汇功能的形成机制、主要影响因素、碳储量评估方法及未来研究方向等方面进行综述。总体来看，湖泊湿地碳汇形成主要受植被初级生产、沉积物碳埋藏、水文过程、营养盐输入、氧化还原环境和人类活动共同调控；碳储量评估方法主要包括样地实测法、沉积柱芯与同位素定年法、遥感反演法、碳收支模型法和多源数据融合方法。未来研究需要加强湖泊湿地植被–水体–沉积物连续体的综合观测，提升不同时间尺度碳储量与碳汇速率的区分能力，并将碳储量、温室气体排放和生态修复管理结合起来，为湖泊湿地碳汇功能提升和生态调控提供科学依据。

Abstract: Lake wetlands are ecological ecotones where terrestrial ecosystems and aquatic ecosystems interact most strongly, and they play an important role in regional carbon cycling and global climate regulation. Compared with typical terrestrial ecosystems such as forests and grasslands, lake wetlands are in a state of long-term water saturation or seasonal inundation. The low-oxygen environment can inhibit organic matter decomposition and promote the long-term preservation of plant residues, suspended particulate organic carbon, and sediment organic carbon, thereby forming an important carbon sink function. In recent years, with the advancement of the “dual carbon” goals and wetland protection and restoration work, the accurate assessment of carbon fixation, carbon storage, and carbon burial rates in lake wetlands has gradually become a research hotspot in wetland ecology and carbon cycle studies. Existing studies have shown that organic carbon burial in lake and reservoir sediments is an important component of the carbon cycle in inland waters, and that lake sediments can remove organic carbon from the short-term biosphere-atmosphere carbon cycle over long timescales. Global studies on organic carbon burial in lakes and reservoirs have also pointed out that although inland waters occupy a limited area, their sedimentary carbon sink function cannot be ignored. This paper reviews the formation mechanisms, main influencing factors, carbon storage assessment methods, and future research directions of the carbon sink function of lake wetlands. Overall, the formation of carbon sinks in lake wetlands is mainly jointly regulated by vegetation primary production, sediment carbon burial, hydrological processes, nutrient input, redox environment, and human activities. The main methods for assessing carbon storage include field plot measurement, sediment cores combined with isotope dating, remote sensing inversion, carbon budget models, and multi-source data fusion methods. Future research needs to strengthen the integrated observation of the lake wetland vegetation-water-sediment continuum, improve the ability to distinguish carbon storage from carbon sink rates at different temporal scales, and combine carbon storage, greenhouse gas emissions, and ecological restoration management, so as to provide a scientific basis for enhancing the carbon sink function and ecological regulation of lake wetlands.