[目的]探讨江西红壤侵蚀区植被恢复过程中不同植被恢复模式的土壤碳储量特征，为揭示植被恢复对土壤碳汇的影响机制和江西红壤侵蚀区生态修复及碳库管理提供科学支撑。[方法]以经过27 a植被恢复与重建后的6种人工植被恢复模式(马尾松Pinus massoniana纯林、湿地松P。elliottii纯林、木荷Schima superba纯林、湿地松-木荷混交林、马尾松补植木荷林、湿地松补植木荷林)为研究对象，以未加人工干扰的自然恢复地为对照，比较不同植被恢复模式土壤有机碳质量分数、储量的变化特征，并分析其影响因素。[结果]①相较于对照，在0～20 cm 土层中，6种人工植被恢复模式土壤有机碳质量分数均有显著增加(P＜0。05);在20～30 cm 土层中，除了马尾松纯林和湿地松纯林外，其余4种人工植被恢复模式土壤有机碳质量分数均显著高于对照(P＜0。05);在30～40 cm 土层中，仅有木荷纯林和湿地松-木荷混交林的土壤有机碳质量分数显著高于对照(P＜0。05)。②研究区7种植被恢复模式的土壤有机碳质量分数均表现出较强的表聚效应，但不同植被恢复模式土层间差异不同，其中木荷纯林最大，0～10 cm 土层土壤有机碳质量分数与30～40 cm 土层相差33。26 g·kg-1，对照最小，仅相差4。90 g·kg-1。③土壤有机碳密度变化规律与质量分数变化规律基本一致，均是植被因子与土壤理化性状共同作用的结果。植被因子中凋落物氮质量分数与土壤有机碳密度的相关系数最大(r=0。322，P＜0。01)，土壤理化性状中土壤有机碳质量分数与土壤有机碳密度的相关系数最大(=0。932，P＜0。01)。④土壤有机碳储量从高到低依次表现为木荷纯林、湿地松-木荷混交林、马尾松补植木荷林、湿地松补植木荷林、湿地松纯林、马尾松纯林，与对照相比，分别增加了 50。12、42。73、38。20、33。03、26。93和20。85 Mg·hm-2，最大提升了 2。46倍，最小提升了1。02倍。[结论]人工植被恢复与重建在红壤侵蚀区效果显著，在研究区今后的建设中可继续推广，以促进植物群落恢复，提高和维持土壤碳库的稳定。图4表2参40
Characteristics and influencing factors of soil carbon stocks in different vegetation restoration models in red soil erosion areas
[Objective]This study is to explore the soil carbon stock characteristics of different vegetation restoration models in the process of vegetation restoration in red soil erosion areas of Jiangxi Province,so as to provide scientific support for revealing the impact mechanism of vegetation restoration on soil carbon sinks and ecological restoration and carbon pool management in red soil erosion areas of Jiangxi Province.[Method]The research objects included 6 types of forest stands after 27 years of vegetation restoration and reconstruction:Pinus massoniana pure forest(PM),P.elliottii pure forest(PE),Schima superba pure forest(SS),P.elliottii and S.superba mixed forest(MES),replanting S.superba with P.massoniana(RMS),and replanting S.superba with P.elliottii(RES).Natural restoration sites without artificial disturbance(ck)were used as controls to compare the changes in soil organic carbon(SOC)content and storage under different vegetation restoration models,and analyze their influencing factors.[Result](1)Compared with ck,SOC mass fraction increased significantly(P＜0.05)in the 0-20 cm soil layer in all 6 artificial vegetation restoration models.In the 20-30 cm soil layer,except for PM and PE,SOC mass fraction of the other 4 vegetation restoration models was significantly higher than that of ck(P＜0.05).In the 30-40 cm soil layer,only SS and MES had significantly higher SOC mass fractions than ck(P＜0.05).(2)SOC mass fractions of the 7 vegetation restoration models in the study area showed a strong surface aggregation effect,but the differences between soil layers of different vegetation restoration models were different,among which SS had the largest SOC mass fraction,with a difference of 33.26 g·kg-1 between 0-10 cm soil layer and 30-40 cm layer,and ck had the smallest difference,with only 4.90 g·kg-1.(3)The change rules of SOC density and SOC content were basically the same,both of which were the result of the joint action of vegetation factors and soil physicochemical properties.The correlation coefficient between litter nitrogen mass fraction(r=0.322,P＜0.01)and SOC density was the largest among vegetation factors,and the correlation coefficient between SOC mass fractions(r=0.932,P＜0.01)and SOC density was the largest among soil physicochemical traits.(4)From high to low,SOC storage increased by 50.12 Mg·hm-2 in SS,42.73 Mg·hm-2 in MES,38.20 Mg·hm-2 in RMS,33.03 Mg·hm-2 in RES,26.93 Mg·hm-2 in PE,and 20.85 Mg·hm-2 in PM,respectively,compared with ck,with a maximum enhancement of 2.46 times and a minimum enhancement of 1.02 times.[Conclusion]Artificial vegetation restoration and reconstruction have significant effects in red soil erosion areas and can be further promoted in future construction in the research area to promote plant community restoration and enhance and maintain the stability of soil carbon pool.[Ch,4 fig.2 tab.40 ref.]
red soil erosion areavegetation restorationcarbon densitydistribution characteristicssoil carbon sequestration
万方数据
维普
