有机肥施用对红壤原生生物与微生物互作的影响

为明确不同施肥处理对土壤原生生物群落、微生物碳代谢活性的影响，以南方典型旱地红壤为研究对象，基于中国科学院鹰潭红壤生态实验站玉米单作系统有机培肥长期定位试验，选取不施肥(M0)、低量猪粪(M1)、高量猪粪(M2)、高量猪粪+石灰(M3)4个处理，利用高通量测序技术研究不同猪粪处理下红壤原生生物多样性、群落结构的变化，揭示原生生物与微生物互作对土壤微生物碳代谢活性和玉米产量的影响。结果表明：(1)长期施用猪粪处理下，土壤pH、有机质(SOM)、全氮(TN)、全磷(TP)、速效磷(AP)和速效钾(AK)的含量显著提高；(2)与M0处理相比，施肥处理显著提高了原生生物生物量和多样性，并且显著改变了其群落结构，其中土壤TP、pH、AP、TN、SOM和AK是原生生物群落结构变化的重要驱动因子；(3)施肥处理显著提高了土壤细菌和真菌生物量，增加了微生物碳代谢活性(Average well color development, AWCD);(4)土壤pH和AP通过影响原生生物多样性和群落结构，间接提高了微生物碳代谢活性和玉米产量。本研究结果为提升旱地红壤的生物多样性，保障土壤健康和维持生态系统服务功...

Impacts of manure application on interaction between protists community and microorganisms in red soil

The purpose of this study was to investigate the protist community and soil microbial carbon metabolism with pig manure application in the dryland red soil of south China. The long-term field experiment was conducted in maize mono-cropping system at the National Agro-Ecosystem Observation and Research Station in Yingtan, Jiangxi Province. Four treatments included no manure (M0), low manure (M1), high manure (M2), and high manure with lime addition (M3). The high-throughput sequencing of 18S rRNA gene was used to explore the diversity and structure of soil protist community, and to estimate the effect of protists-microorganisms interaction on microbial carbon metabolism and maize yield. Our results showed that soil chemical properties significantly varied under the four fertilization treatments. Soil pH, soil organic matter (SOM), total nitrogen (TN), total phosphorus (TP), available phosphorus (AP), and available potassium (AK) were significantly increased under manure treatments. Compared with M0 treatment, manure treatments (M1, M2, and M3) significantly enhanced the biomass and diversity of protist, and remarkably modified the protist community structure. The protist community composition was mainly affected by soil TP, pH, AP, TN, SOM, and AK. Manure application significantly improved the bacterial and fungal biomasses, and consequently promoted microbial carbon metabolism indicated by the values of average well color development (AWCD). Structural equation modelling indicated that soil pH and AP could indirectly increase microbial carbon metabolism and maize yield through regulating the diversity and structure of protist community. Taken together, we provide the scientific basis for promoting the microbial diversity in the dryland red soil, and maintaining soil health and ecosystem service functioning.