Wang Yanfang, Liu Ling, Yue Feixue, Li Dong
College of Agriculture, Henan University of Science and Technology, Luoyang, Henan, China.
State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Northwest Agriculture and Forestry University, Yangling, China.
PeerJ. 2019 Sep 18;7:e7708. doi: 10.7717/peerj.7708. eCollection 2019.
In China's Loess Plateau, afforestation and reforestation are considered the foremost practices for sequestering carbon and conserving soil and water. In order to evaluate the carbon storage changes of tree, soil, and litter, and the soil total nitrogen (STN) in two typical artificial forests in the region, we conducted plot surveys for different ages of both artificial forest types. Soil samples were collected at different depths from 0-100 cm. The results indicated that forest ecosystem carbon storage increased with tree development. The rates of mean annual carbon sequestration of and plantation ecosystems were 3.31 and 3.53 Mg ha year, respectively. The rate of mean annual carbon sequestration of plantation ecosystems was higher by 6.65% than that of plantation ecosystems. The soil organic carbon (SOC) and STN decreased at deeper soil depths in both plantations at different stand ages, significantly decreasing in the 0-60 cm of soil ( < 0.05), and the highest SOC content and storage were in the top 0-20 cm of soil. The temporal patterns for SOC and STN changes at different soil sampling depths from 0 to 100 cm all showed an initial decrease during the early stage of restoration, and then an increase that coincided with the development of the two plantation forests. At 0-100 cm depth, the SOC storage was in the range of 40.95-106.79 and 45.13-113.61 Mg ha for the forest and forest, respectively. The STN storage in the 0-100 cm soil layer with the stand age development ranged from 4.16 to 8.34 Mg ha in the plantation and 4.19-7.55 Mg ha in the forest. The results showed a significant positive correlation between SOC and STN. This study suggests that we should pay more attention to changes in soil carbon and nitrogen sequestration during long-term vegetation restoration.
在中国黄土高原地区，造林和再造林被视为固碳以及水土保持的首要措施。为了评估该地区两种典型人工林中树木、土壤和凋落物的碳储量变化以及土壤全氮（STN）情况，我们针对这两种人工林类型的不同树龄进行了样地调查。在0至100厘米的不同深度采集土壤样本。结果表明，森林生态系统碳储量随树木生长而增加。[此处原文缺失两种人工林名称，无法准确翻译]人工林生态系统的年均固碳率分别为3.31和3.53 Mg ha⁻¹ year⁻¹。[此处原文缺失两种人工林名称，无法准确翻译]人工林生态系统的年均固碳率比[此处原文缺失另一种人工林名称，无法准确翻译]人工林生态系统高6.65%。在不同林龄的两种人工林中，土壤有机碳（SOC）和STN在土壤较深处均有所下降，在0至60厘米土层中显著下降（P < 0.05），且SOC含量和储量最高的是土壤表层0至20厘米。从0至100厘米不同土壤采样深度的SOC和STN变化的时间模式均显示，在恢复初期呈下降趋势，随后随着两种人工林的生长而增加。在0至100厘米深度，[此处原文缺失两种人工林名称，无法准确翻译]林和[此处原文缺失另一种人工林名称，无法准确翻译]林的SOC储量分别在40.95 - 106.79和45.13 - 113.61 Mg ha之间。随着林龄增长，0至100厘米土层中的STN储量在[此处原文缺失一种人工林名称，无法准确翻译]人工林中为4.16至8.34 Mg ha，在[此处原文缺失另一种人工林名称，无法准确翻译]林中为4.19 - 7.55 Mg ha。结果表明，SOC与STN之间存在显著正相关。本研究表明，在长期植被恢复过程中，我们应更加关注土壤碳氮固存的变化。
