کودهای آلی و معدنی و هدایت ترکیبات باکتریایی همزیگاه در خاک در چین
Abstract
1- Introduction
2- Material and methods
3- Results
4- Discussion
5- Conclusion
References
Abstract
Soil microbes play vital roles in energy flow and nutrient cycling and, thus, are important for agricultural production. A better understanding of the complex responses of microbial communities to various organic and inorganic fertilization regimes is critical for sustainable development of agroecosystems. Changes in bacterial and fungal abundance and diversity in fluvo-aquic soil in Northern China were studied under 38-year long-term fertilization strategies: four chemical-fertilization strategies (i.e., no fertilizer, N, NP, or NPK), with or without manure amendment, were investigated by high-throughput sequencing and quantitative polymerase chain reaction-based amplification of bacterial 16S rRNA and fungal internal transcribed spacer (ITS) rRNA genes. Chemical fertilizer plus manure addition clearly increased the soil fertility and was recommended for further optimization of fertilization patterns. Both principal component analysis and partial least-square discriminant analysis showed greater impacts of manure addition than chemical fertilizer on bacterial community distributions, whereas fungal communities were more sensitive to inorganic fertilizer. The linear discriminant analysis effect size method revealed that the number of responding microbes (microbes significantly affected by various fertilizations) in bacterial communities in manure-treated soils was markedly higher than that in chemical fertilizer-treated soils, whereas those of fungal communities showed the opposite trend. In addition, redundancy analysis further illustrated the primary importance of organic matter in shaping community distributions of bacteria, rather than in driving fungal community patterns. These results suggested that organic and inorganic fertilizers, respectively, dominated in shaping bacterial and fungal community distributions in fluvo-aquic soils.
Introduction
Soil microorganisms play vital roles in the maintenance of soil health, productivity, and sustainability, and thus crop production, because of their contributions to soil nutrient transformation, formation and decomposition of organic matter, and stabilization of soil aggregates (Van Der Heijden et al., 2008; Zhao et al., 2014; Singh, 2016; Pan et al., 2018a). Therefore, a profound understanding of soil microbial ecology has become increasingly recognized and emphasized because of the ecological and economic importance of microorganisms (Mele and Crowley, 2008). Due to the increasing concerns regarding food demands and the scarcity of land available for agriculture, high amount of fertilizer is implemented to increase crop productivity (Inselsbacher et al., 2010). The application of organic and inorganic fertilizers can cause detectable changes in nutrient availability to plants, as well as in the diversity and function of microorganisms (Marschner et al., 2003). For example, long-term field experiments involving polymerase chain reaction (PCR)-denaturing gradient gel electrophoresis (DGGE) demonstrated the importance of balanced fertilization in promoting the activities of bacterial communities (Chu et al., 2007a,b; Luo et al., 2015). Nitrogen (N) is regarded as a key limiting factor for soil microbes, and N amendment can alter the activity and diversity of soil organisms (Sarathchandra et al., 2001; Xu et al., 2017; Liu et al., 2019). Organic fertilization exerted no effects on the fungal biomass, while increasing the bacterial biomass by increasing soil organic carbon (Corg) and C/N ratio (Crecchio et al., 2001; Marschner et al., 2003). In addition, manure application promoted soil bacterial communities by enhancing root exudates and also improved plant growth (Bittman et al., 2005). Suzuki et al.