Li Jinsheng, Zhao Yinquan, Shao Xinqing, Huang Ding, Shang Jianying, Li Hui, He Yixuan, Liu Kesi
College of Grassland Science and Technology, China Agricultural University, Beijing, China.
College of Tourism and Urban Planning, Chengdu University of Technology, Chengdu, China.
Front Plant Sci. 2021 Nov 22;12:765041. doi: 10.3389/fpls.2021.765041. eCollection 2021.
The degradation of the grassland system has severely threatened the safety of the ecological environment and animal husbandry. The supplement of key substances lost due to degradation is widely used to accelerate the restoration of the degraded grassland ecosystem. In this study, we investigated the effects of biochar and nitrogen addition on soil properties and microorganisms of degraded alpine grassland. The experimental treatments consisted of the control without any addition, only nitrogen addition (10 gN/m), only biochar addition (4.00 kg/m biochar), and the mixed addition of biochar and nitrogen (4.00 kg/m biochar and 10 gN/m nitrogen, respectively). Adding N alone did not significantly change the pH, total organic carbon (TOC), total nitrogen (TN), microbial biomass (MB), and the composition proportion of microbes of the soil, but increased the contents of soil water content (SWC), NH -N, NO -N, available phosphorus (AP), and the biomass of bacteria and fungi. The addition of biochar or the mixture of biochar and nitrogen increased the contents of pH, TOC, TN, MB, SWC, NH -N, NO -N, AP, bacteria, and fungi in the soil and changed the structure of the soil microbial community. The increasing intensity of AP, bacteria, and fungi under the addition of biochar or the mixture of biochar and nitrogen was significantly greater than that under N addition alone. These results indicated that the separated addition of nitrogen and biochar and the mixed addition of biochar and nitrogen all improved the soil condition of the moderate-severe degraded alpine grassland, but the mixed addition of biochar and nitrogen could be a better strategy to remediate the degraded alpine grassland.
草原系统的退化严重威胁到生态环境和畜牧业的安全。补充因退化而流失的关键物质被广泛用于加速退化草原生态系统的恢复。在本研究中，我们调查了生物炭和氮添加对退化高寒草原土壤性质和微生物的影响。实验处理包括不添加任何物质的对照、仅添加氮（10 gN/m）、仅添加生物炭（4.00 kg/m生物炭）以及生物炭和氮的混合添加（分别为4.00 kg/m生物炭和10 gN/m氮）。单独添加氮并没有显著改变土壤的pH值、总有机碳（TOC）、总氮（TN）、微生物生物量（MB）以及微生物的组成比例，但增加了土壤含水量（SWC）、NH₄⁺-N、NO₃⁻-N、有效磷（AP）的含量以及细菌和真菌的生物量。添加生物炭或生物炭与氮的混合物增加了土壤中pH值、TOC,、TN、MB、SWC、NH₄⁺-N、NO₃⁻-N、AP、细菌和真菌的含量，并改变了土壤微生物群落结构。添加生物炭或生物炭与氮的混合物时，AP、细菌和真菌的增加强度显著大于单独添加氮时。这些结果表明，单独添加氮和生物炭以及生物炭与氮的混合添加都改善了中度-重度退化高寒草原的土壤状况，但生物炭与氮的混合添加可能是修复退化高寒草原的更好策略。
