近20年间鄱阳湖湿地春秋季植被生物量时空动态

Spatial and Temporal Dynamics of Plant Biomass in Poyang Lake Wetland in Spring and Autumn in Recent Two Decades

湿地生态系统是碳密度最大的生态系统之一,摸清湿地植被生物量及其动态变化对于实现“双碳”目标具有重要意义。基于Landsat遥感影像对鄱阳湖湿地2000—2020年间春秋季的植被地上生物量进行了反演和估算,分析了植被生物量随时间的变化趋势以及空间热点区域。结果表明:①近20年间鄱阳湖湿地春季和秋季植被地上生物量分别为0.85×10^(9)~4.20×10^(9) g和0.68×10^(9)~6.69×10^(9) g,春季植被地上生物量随时间变化不明显,秋季植被地上生物量随时间呈上升趋势。②鄱阳湖湿地春季植被地上生物量分布热点区域面积为754.15 km^(2),秋季为1085.49 km^(2),分别占鄱阳湖湿地总面积的21.58%和30.66%。③鄱阳湖湿地春季和秋季植被地上生物量与月均温度呈显著正相关关系。鄱阳湖湿地植被碳汇功能较强,且呈平稳甚至上升趋势,有利于碳中和目标的实现。

Wetlands possess some of the highest carbon densities among ecosystems.Understanding the dynamics and growth trends of wetland vegetation biomass is crucial for achieving the carbon peaking and carbon neutrality goals.Based on LandSat remote sensing images,we estimated the aboveground vegetation biomass in Poyang Lake wetland during spring and autumn between 2000 and 2020,and examined its development trend in different growing seasons and hotspot areas.The findings revealed that:1)In recent two decades,aboveground vegetation biomass in spring ranged from 0.85×10^(9) to 4.20×10^(9) g,while in autumn from 0.68×10^(9) to 6.69×10^(9) g.Spring biomass remained stable,whereas autumn biomass exhibited a consistent increase over time.2)Hotspot areas for aboveground vegetation biomass in spring and autumn covered 754.15 km^(2) and 1085.49 km^(2),respectively,representing 21.58%and 30.66%of the total wetland area.3)Spring and autumn biomass showed a positive correlation with monthly mean temperature.The vegetation in Poyang Lake wetland serves as a robust carbon sink,aiding in the pursuit of carbon peaking and carbon neutrality.