Mohammed VI Polytechnic University, Lot 660, Hay Moulay Rachid, 43150, Benguerir, Morocco.
OCP-Africa, 2-4, rue Al Abtal, Hay Erraha, 20 200, Casablanca, Morocco.
Sci Rep. 2018 Nov 20;8(1):17061. doi: 10.1038/s41598-018-34736-6.
Little is known to what extent soil biota, in particular, the mycorrhizae are altered through different fallow durations/types in tropical soils. We found that soil-N, -C, -Al, -K and -Ca contents significantly differed due to the fallow durations/types. Subsequently, the effects of fallow types and soil depths on the diversity, species richness and community structure of arbuscular mycorrhizal (AM) fungi were examined. A higher AM species richness was identified in the cropping than in forest fallow fields, suggesting a positive cropping feedback on the AM community composition. Distribution of the AM species was positively related to soil properties, specifically soil-pH, and soil-Pi, -Ca and -Mg contents. The soil properties conjointly accounted for 78.5% of explained variation in the AM community composition, signifying that the main factors altering the community structure under different fallow and cropping systems were the soil properties. Among the soil chemical characteristics, the soil-pH disclosed a significant explained variation in the AM community composition in the topsoil layer under the short fallow. Structural modeling equation to understand multiple predictive pathways that connect soil properties, fallow practices and AM community structures indicated that soil-C, -N and -Ca contents were highlighted as important factors influencing the AM community compositions.
目前人们对于在热带土壤中，不同休耕时间/类型会在何种程度上改变土壤生物群，尤其是菌根真菌知之甚少。我们发现，由于休耕时间/类型的不同，土壤中的氮、碳、铝、钾和钙含量有显著差异。随后，我们研究了休耕类型和土壤深度对丛枝菌根（AM）真菌多样性、物种丰富度和群落结构的影响。与森林休耕田相比，耕作田中的 AM 物种丰富度更高，这表明耕作对 AM 群落组成有积极的反馈作用。AM 物种的分布与土壤特性，特别是土壤 pH 值和土壤 Pi、Ca 和 Mg 含量呈正相关。这些土壤特性共同解释了 AM 群落组成的 78.5%的变异，表明在不同休耕和耕作系统下改变群落结构的主要因素是土壤特性。在土壤化学特性中，在短期休耕的表土层中，土壤 pH 值对 AM 群落组成的解释变异最大。结构建模方程用于理解连接土壤特性、休耕实践和 AM 群落结构的多个预测途径，结果表明，土壤 C、N 和 Ca 含量是影响 AM 群落组成的重要因素。
