College of Animal Science, Guizhou University, Guiyang 550025, China.
State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China.
Int J Environ Res Public Health. 2022 Sep 1;19(17):10936. doi: 10.3390/ijerph191710936.
This study explored the relationship between soil organic carbon (SOC) and root distribution, with the aim of evaluating the carbon stocks and sequestration potential under five plant communities (, , , , and ) in an arid region, the Sangong River watershed desert ecosystem. Root biomass, ecological factors, and SOC in different layers of a 0-100 cm soil profile were investigated. The results demonstrated that almost all living fine root biomass (11.78-34.41 g/m) and dead fine root biomass (5.64-15.45 g/m) levels were highest in the 10-20 cm layer, except for the community, which showed the highest living and dead fine root biomass at a depth of 60-70 cm. Fine root biomass showed strong seasonal dynamics in the five communities from June to October. The biomass levels of the (138.31 g/m) and (229.73 g/m) communities were highest in August, whereas those of the (87.76 g/m), (66.29 g/m), and (148.31 g/m) communities were highest in September. The SOC of the five communities displayed strong changes with increasing soil depth. The mean SOC value across all five communities was 77.36% at 0-30 cm. The highest SOC values of the (3.08 g/kg), (2.35 g/kg), and (2.34 g/kg) communities were found in June, and the highest value of the (2.25 and 2.31 g/kg, > 0.05) community was found in June and September. The highest SOC values of the (1.88 g/kg) community were found in July. Fine root production and turnover rate were 50.67-486.92 g/m/year and 1.25-1.98 times per year. The relationships among SOC, fine root biomass, and ecological factors (soil water content and soil bulk density) were significant for all five communities. Based on the results, higher soil water content and soil conductivity favored the decomposition of root litter and increased fine root turnover, thereby facilitating SOC formation. Higher pH and bulk density levels are not conducive to soil biological activity and SOC mineralization, leading to increased SOC levels in desert regions.
本研究探讨了土壤有机碳（SOC）与根系分布之间的关系，旨在评估在干旱地区（三工河流域沙漠生态系统）的五个植物群落（，，，，和）下的碳储量和固碳潜力。研究了不同土层 0-100cm 土壤剖面中的根系生物量、生态因子和 SOC。结果表明，除了 群落外，几乎所有活细根生物量（11.78-34.41g/m）和死细根生物量（5.64-15.45g/m）水平都在 10-20cm 层最高，而 群落则在 60-70cm 深处表现出最高的活细根和死细根生物量。五个群落的细根生物量在 6 月至 10 月之间具有强烈的季节性动态。8 月时，群落（138.31g/m）和群落（229.73g/m）的生物量水平最高，而群落（87.76g/m）、群落（66.29g/m）和群落（148.31g/m）的生物量水平则在 9 月最高。五个群落的 SOC 随土壤深度的增加而发生强烈变化。五个群落的平均 SOC 值在 0-30cm 处为 77.36%。群落（3.08g/kg）、（2.35g/kg）和（2.34g/kg）的 SOC 值最高，均出现在 6 月，而群落（2.25 和 2.31g/kg，>0.05）的 SOC 值最高则出现在 6 月和 9 月。群落（1.88g/kg）的 SOC 值最高出现在 7 月。细根生产力和周转率分别为 50.67-486.92g/m/year 和 1.25-1.98 次/年。SOC、细根生物量和生态因子（土壤含水量和土壤容重）之间的关系对所有五个群落都具有重要意义。基于这些结果，较高的土壤含水量和土壤电导率有利于根屑的分解和细根周转率的提高，从而促进 SOC 的形成。较高的 pH 值和容重水平不利于土壤生物活性和 SOC 矿化，导致沙漠地区 SOC 水平升高。
