Chen Mingyu, Yang Xi, Shao Ming'an, Wei Xiaorong, Li Tongchuan
College of Natural Resources and Environment, Northwest A & F University, Yangling 712100, China; State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, Northwest A&F University, Yangling 712100, China.
College of Natural Resources and Environment, Northwest A & F University, Yangling 712100, China; State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, Northwest A&F University, Yangling 712100, China; Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100190, China.
Sci Total Environ. 2022 Dec 15;852:158380. doi: 10.1016/j.scitotenv.2022.158380. Epub 2022 Aug 30.
Vegetation restoration is one of the principal strategies for ecosystem recovery in degraded land of fragile regions, which is an important driving factor for soil fertility and elemental circulation. While the relationship between revegetation and soil C-N-P stoichiometry remains unclear. To evaluate the relationships between vegetation restoration and soil C-N-P stoichiometry, the distribution of soil C, N, and P within 0-30 cm soil depth under five typical artificial restored vegetation types on the Loess Plateau was analyzed and the influencing factors were evaluated. The results showed that soil C, N, and P contents were relatively lower at the study site than the mean values for topsoil in China. Compared with other vegetation types (Populus simonii Carr., Pinus tabuliformis Carr., and Caragana korshinskii Kom.), Medicago Sativa L. and Stipa bungeana Trin. helped improve soil fertility better; the soil organic carbon (SOC), total nitrogen (TN), and total phosphorus (TP) contents within the 0-30 cm soil layer respectively maximized under Stipa bungeana Trin. (3.30 g kg), Medicago Sativa L. (0.34 g kg), and Medicago Sativa L. (0.41 g kg). The values of soil C/N, C/P, and N/P for the five vegetation types were 9.50-11.85, 15.36-21.47, and 1.29-1.90, respectively. The contents of SOC and TN under the five vegetation types were significantly (P < 0.001) affected by soil depth and vegetation type (P < 0.001) and decreased with increasing soil depth. However, the TP content was significantly (P < 0.001) affected by vegetation type and not by soil depth. Considering the better adaptability of native species, native herb vegetation types should be considered first for ecological restoration in semiarid continental climate zones.
植被恢复是脆弱地区退化土地生态系统恢复的主要策略之一，是土壤肥力和元素循环的重要驱动因素。然而，植被恢复与土壤碳氮磷化学计量比之间的关系尚不清楚。为了评估植被恢复与土壤碳氮磷化学计量比之间的关系，分析了黄土高原五种典型人工恢复植被类型下0-30厘米土壤深度内土壤碳、氮、磷的分布，并评估了影响因素。结果表明，研究区土壤碳、氮、磷含量低于中国表层土壤平均值。与其他植被类型（小叶杨、油松和柠条锦鸡儿）相比，紫花苜蓿和长芒草更有助于提高土壤肥力；在长芒草（3.30克/千克）、紫花苜蓿（0.34克/千克）和紫花苜蓿（0.41克/千克）下，0-30厘米土层内的土壤有机碳（SOC）、全氮（TN）和全磷（TP）含量分别达到最大值。五种植被类型的土壤C/N、C/P和N/P值分别为9.50-11.85、15.36-21.47和1.29-1.90。五种植被类型下的SOC和TN含量受土壤深度和植被类型的显著影响（P<0.001），并随土壤深度增加而降低。然而，TP含量受植被类型的显著影响（P<0.001），不受土壤深度影响。考虑到本土物种更好的适应性，在半干旱大陆气候区进行生态恢复时，应首先考虑本土草本植被类型。
