Co-Innovation Center for Soil-Water and Forest-Grass Ecological Conservation in Yellow River Basin of Shandong Higher Education Institutions, College of Forestry, Shandong Agricultural University, Tai'an 271018, China; Mountain Tai Forest Ecosystem Research Station of State Forestry and Grassland Administration, Tai'an 271018, China.
Water Resources Research Institute of Shandong Province, Ji'nan 250000, China.
Sci Total Environ. 2024 Nov 1;949:175127. doi: 10.1016/j.scitotenv.2024.175127. Epub 2024 Jul 30.
Salinization is a global problem affecting agricultural productivity and sustainability. The application of exogenous microbial fertilizer harbors great potential for improving saline-alkali soil conditions and increasing land productivity. Yet the responses to microbial fertilizer application rate in terms of rhizosphere soil biochemical characteristics, soil microbial community, and crop yield and their interrelationships and underlying mechanisms are still unclear. Here, we studied changes to rhizosphere soil-related variables, soil enzyme activity (catalase, sucrase, urease), microbial community diversity, and sweet sorghum (Sorghum bicolor (L.) Moench) yield under four fertilization concentration levels (0, 0.12, 0.24, and 0.36 kg m) in a saline-alkali ecosystem (Shandong, China). Our results showed that the best improvement effect on soil when the microbial fertilizer was applied at a rate of 0.24 kg m. Compared with the control (sweet sorghum + no fertilizer), it significantly increased soil organic carbon (21.50 %), available phosphorus (26.14 %), available potassium (36.30 %), and soil urease (38.46 %), while significantly reducing soil pH (2.21 %) and EC (12.04 %). Meanwhile, the yield of sweet sorghum was increased by 24.19 %. This is mainly because microbial fertilizers enhanced the diversity and the network complexity of bacterial and fungal communities, and influenced catalase (CAT), urease (UE), and sucrase (SC), thereby facilitating nutrient release in the soil, enhancing soil fertility, and indirectly influencing sweet sorghum productivity. Among them, Gemmatimonadota and Verrucomicrobiota may be the key microbial factors affecting sweet sorghum yield, while available potassium, soil urease and available phosphorus are the main soil factors. These findings provide valuable theoretical insights for preserving the health of coastal saline-alkali soils and meeting the agricultural demand for increased yield per unit of land area.
盐渍化是一个全球性问题，影响着农业生产力和可持续性。外源微生物肥料的应用在改善盐碱地条件和提高土地生产力方面具有巨大潜力。然而，微生物肥料施用量对根际土壤生化特性、土壤微生物群落、作物产量及其相互关系和潜在机制的响应仍不清楚。在这里，我们研究了在山东盐碱生态系统中，四种施肥浓度（0、0.12、0.24 和 0.36 kg·m-2）下，根际土壤相关变量、土壤酶活性（过氧化氢酶、蔗糖酶、脲酶）、微生物群落多样性和甜高粱（Sorghum bicolor (L.) Moench）产量的变化。结果表明，当微生物肥料施用量为 0.24 kg·m-2 时，对土壤的改善效果最佳。与对照（甜高粱+无肥）相比，它显著增加了土壤有机碳（21.50%）、有效磷（26.14%）、有效钾（36.30%）和土壤脲酶（38.46%），同时显著降低了土壤 pH（2.21%）和 EC（12.04%）。同时，甜高粱的产量增加了 24.19%。这主要是因为微生物肥料增强了细菌和真菌群落的多样性和网络复杂性，并影响了过氧化氢酶（CAT）、脲酶（UE）和蔗糖酶（SC），从而促进了土壤中养分的释放，提高了土壤肥力，间接地影响了甜高粱的生产力。其中，Gemmatimonadota 和 Verrucomicrobiota 可能是影响甜高粱产量的关键微生物因素，而有效钾、土壤脲酶和有效磷是主要的土壤因素。这些发现为保护沿海盐碱地的健康和满足单位土地面积农业产量增加的需求提供了有价值的理论见解。
