若尔盖高寒沙化草地恢复过程中土壤全碳和植物根系特征的变化  

Changes of soil total carbon and plant root characteristics during restoration of Zoige alpine desertified grassland

作　　者：李露航 类延宝 陈秋捷 邓先智 包寒阳 扎琼巴让 孙庚[1] LI Lu-hang;LEI Yan-bao;CHEN Qiu-jie;DENG Xian-zhi;BAO Han-yang;ZHA Qiong Barang;SUN Geng(China-Croatia“Belt and Road”Joint Laboratory on Biodiversity,CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization&Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province,Chengdu 610041,China;Chengdu Institute of Biology,Chinese Academy of Sciences,Chengdu 610041,China;Qinghai-Tibet Plateau Research Institute,Southwest University for Nationalities,Chengdu 610041,China;Zhaqiongcang Ecological Culture Exchange Center,Gannan Tibetan Autonomous Prefecture 747205,Gansu,China)

机构地区：[1]中国-克罗地亚生物多样性和生态系统服务“一带一路”联合实验室,中国科学院山地生态恢复与生物资源利用重点实验室,生态恢复与生物多样性保育四川省重点实验室,成都610041 [2]中国科学院成都生物研究所,成都610041 [3]西南民族大学青藏高原研究院,成都610041 [4]扎琼仓生态文化交流中心,甘肃甘南藏族自治州747205

出　　处：《生态学杂志》2023年第2期282-290,共9页Chinese Journal of Ecology

基　　金：国家科技部重点研发项目(2020YFE0203200);第二次青藏高原综合科学考察研究项目(2019QZKK0302-02);四川省科技厅项目(2020YFH0001,2020YFH0215,2021YFH0008,2021ZHYZ0002和2021YFN0105)资助。

摘　　要：草地对全球碳循环和土壤碳固存的重要性越来越受到重视。我国草地约95%的碳都储存在土壤中。本研究以若尔盖高寒草地为对象,选取了未恢复、恢复1年、恢复4年、恢复8年的4块沙化草地,探究高寒草地恢复过程中土壤全碳和植物根系特征的变化。结果表明:若尔盖高寒草地土壤碳含量受恢复时间和土壤深度的影响,恢复草地的土壤全碳、有机碳和无机碳含量皆高于未恢复草地;有机碳含量在恢复8年达到最高,而无机碳则在恢复1年最高,分别是未恢复草地的7.55、11.78倍;恢复1年、恢复4年草地的土壤有机碳含量表层(0~20 cm)低于深层(20~50 cm),而恢复8年草地则是深层低于表层;而土壤无机碳无论是恢复1年、恢复4年、恢复8年的草地皆是0~5 cm土层的最高;有机碳/无机碳比为恢复4年>恢复8年>恢复1年,且深层(20~70 cm)土壤有机碳占比要高于表层(0~20 cm);根系特征(根长、根体积、组织密度和根生物量)随着恢复时间增加而增加并与土壤有机碳显著正相关(P<0.05),而与土壤无机碳含量无显著相关(P>0.05),土壤无机碳含量与pH显著正相关(P<0.05);在沙化草地恢复过程中,土壤碳含量显著升高,草地植物群落和土壤理化性质也逐步改善。因此,对退化草地实施人工干预,进行次生演替,是增加高寒退化草地土壤碳汇的一种有效策略。The importance of grasslands to soil carbon sequestration and global carbon cycle has been well recognized. About 95% of the carbon in grasslands of China is stored in soil. We selected four desertified grasslands with different restoration durations of 0, 1, 4, 8 years to examine the changes of soil carbon pool and root characteristics during the restoration of alpine grassland in Zoige. The results showed that soil carbon content in Zoige alpine grassland was affected by restoration duration and soil depth. The contents of soil total carbon, organic carbon, and inorganic carbon in the restored grasslands were higher than those in the unrestored grassland. Soil organic carbon content was the highest in the grassland restored for 8 years, while inorganic carbon content was the highest in the grassland restored for 1 year, which were 7.55 and 11.78 times of that in the unrestored grassland, respectively. Soil organic carbon content in surface layer(0-20 cm) was lower than that in deep layer(20-50 cm) in the grassland restored for 1 year and 4 years, while soil organic carbon content in surface layer was higher than that in deep layer in the grassland restored for 8 years. Soil inorganic carbon content in the grassland restored for 1 year, 4 years, and 8 years was the highest in 0-5 cm soil layer. The ratio of soil organic carbon to inorganic carbon was in an order of the grasslands restored for 4 years > 8 years > 1 year, and the proportion of soil organic carbon in deep layer(20-70 cm) was higher than that of surface layer(0-20 cm). Root characteristics(root length, root volume, tissue density, and root biomass) increased with increasing restoration time, and were significantly positively correlated with soil organic carbon, but not with soil inorganic carbon content. Soil inorganic carbon content was positively correlated with pH. During the restoration of desertified grassland, soil carbon content significantly increased, and plant community and soil physicochemical properties were gradually improved. Therefore

关 键 词：若尔盖 沙化草地 土壤全碳 根系特征 草地恢复 

分 类 号：S812.2[农业科学—草业科学]