包头南海湖沉积物有机碳空间分布特征

为了解包头南海湿地的有机碳分布特点及碳库稳定性,以南海湖沉积物有机碳为研究对象,利用活性有机碳及其占总有机碳比例,分析其空间分布特征及碳库稳定性。结果表明:有机碳含量在垂向总体呈现随沉积物深度增加而降低的趋势,总有机碳含量在3.96~28.35 g·kg~(-1)之间,平均值为13.11 g·kg~(-1),活性有机碳含量在1.16~16.47 g·kg~(-1)之间,平均值为6.12 g·kg~(-1),活性有机碳含量占总有机碳含量的34.19%~54.64%。变异系数均在10%~100%之间,属中等变异,0~10 cm层、10~20 cm层沉积物中有机碳含量峰值集中在0~10 cm层,在8.91~28.35 g·kg~(-1)之间,平均值为16.52 g·kg~(-1),活性有机碳含量整体所占比例较大,有机碳易受到干扰,碳库稳定性较低,但整体以惰性有机碳含量为主,亦属稳定碳库;水平分布总体呈现从湖心向四周逐减的规律,但进水口和芦苇区的有机碳含量较高,活性有机碳以湖心为最高,总有机碳含量越高,活性有机碳含量也越高,湖心小岛处活性有机碳占总有机碳含量的44.16%,湖心处为43.47%,但芦苇区总有机碳含量最高,而活性有机碳含量却较低,活性有机碳含量占总有机碳含量的39.78%,以稳定的惰性有机碳为主,属稳定碳库,表明芦苇对碳库稳定较为有利。研究表明,沉积物碳库稳定性受芦苇区和人为活动影响,随着沉积物深度的增加碳库稳定性增强。

Spatial distribution characteristics of the organic carbon insediments of Nanhai Lake in Baotou City

As one of the important carbon pools in the ecosystem, lake organic carbon pools are major carbon reserves for atmospheric CO₂. Their stability is of great significance to the entire ecosystem. This essay considered the organic carbon of Nanhai Lake sediments as the research object, analyzing its spatial distribution characteristics and stability, based on the ratio of active organic carbon to total organic carbon. The results showed that the organic carbon content decreased vertically along with the increase in sediment depth, while the total organic carbon varied between 3.96 and 28.35 g·kg^-1, with an average of 13.11 g·kg^-1. The active organic carbon ranged from 1.16 to 16.47 g·kg^-1, with an average of 6.12 g·kg^-1. Thus, the active organic carbon ranged from 34.19 to 54.64 percent of the total organic carbon. Its coefficient of variation, between 10 and 100 percent, appeared moderately variable. The organic carbon content varied between 8.91 and 28.35 g·kg^-1, with an average of 16.52 g·kg^-1, peaking at a depth of 0 to 10 cm. Meanwhile, the active organic carbon occupied a large proportion of the total. As a result, its susceptibility to interference contributed to the poor stability of the carbon pool. However, due to the inertness of the organic carbon in general, the entire carbon pool seemed stable. The results also demonstrated that the organic carbon content decreased horizontally along the radius of the lake, with the maximum being at the center of the lake, along with a high content in the influent and ditch reed areas. The higher the total organic carbon, the higher the active organic carbon. The active organic carbon accounted for 44.16 percent of the total on the central island, with 43.47 percent at the lake center. The total organic carbon reached the maximum in ditch reed areas, where a significantly lower content of active organic carbon, at 39.78 percent, was detected. In the same way, the inert organic carbon occupied a large proportion, with the carbon pool appearing stable. To sum up, the stability of the sediment carbon pools can be affected by ditch reed areas and human activities, with an increase in the sediment depth corresponding to an increase in their stability.