原生生物在土壤微生物组中起到枢纽作用,在时间、空间维度上对原生生物分布格局及其对根系微生态影响的研究具有重要意义。本研究按照空间换时间法,选择同一桑园不同树龄(10龄、80龄,200龄左右)桑(Morus alba L.)根际土壤作为样本,利用I...原生生物在土壤微生物组中起到枢纽作用,在时间、空间维度上对原生生物分布格局及其对根系微生态影响的研究具有重要意义。本研究按照空间换时间法,选择同一桑园不同树龄(10龄、80龄,200龄左右)桑(Morus alba L.)根际土壤作为样本,利用Illumina高通量测序技术测定土壤原生生物种类多样性、群落组成差异并分析了其驱动因素,为探讨桑根际原生生物的生态学稳定性机制奠定基础。结果表明,不同树龄桑树原生生物群落优势门基本一致,主要为金藻门Chrysophyta、Kinetoplastida、硅藻门Bacillariophyta、轮虫门Rotaliida、卵菌门Oomycetes和Petalomonadida,但相对丰度存在差异,在10a vs 80a、10a vs 200a和80a vs 200a中相对丰度差异显著的属分别为Paracercomonas、Petalomonas和变形虫Acanthamoeba、吻滴虫属Rhynchomonas,表明土壤原生生物群落在属水平上组成和相对丰度具有明显树龄变异。原生生物多样性受到土壤理化性质的影响,群落多样性、丰富度和均匀度与氯离子含量极显著负相关,Simpson指数与全盐量显著负相关,群落覆盖度与速效钾和碱解氮含量显著正相关。桑根际原生生物与真菌、细菌之间存在共同的环境偏好或潜在的生物相互作用。展开更多
The standard k-ε turbulence model and discrete phase model (DPM) were used to simulate the heat and mass transfer in a liquid-desiccant evaporator driven by a heat pump using FLUENT software, and the temperature fiel...The standard k-ε turbulence model and discrete phase model (DPM) were used to simulate the heat and mass transfer in a liquid-desiccant evaporator driven by a heat pump using FLUENT software, and the temperature field and velocity field in the device were obtained. The performance of the liquid-desiccant evaporator was studied as the concentration of the inlet solution varied between 21% and 30% and the pipe wall temperature between 30 and 50 ℃. Results show that the humidification rate and the humidification efficiency increased with the inlet air temperature, the solution flow rate, the solution temperature, and the pipe wall temperature. The humidification rate and humidification efficiency decreased with increasing moisture content in inlet air and the concentration of inlet solution. The humidification rate increased substantially but the humidification efficiency decreased as the inlet air flow rate increased. The error between the simulations and experimental results is acceptable, meaning that our model can provide a theoretical basis for optimizing the performance of a humidifying evaporator.展开更多
文摘原生生物在土壤微生物组中起到枢纽作用,在时间、空间维度上对原生生物分布格局及其对根系微生态影响的研究具有重要意义。本研究按照空间换时间法,选择同一桑园不同树龄(10龄、80龄,200龄左右)桑(Morus alba L.)根际土壤作为样本,利用Illumina高通量测序技术测定土壤原生生物种类多样性、群落组成差异并分析了其驱动因素,为探讨桑根际原生生物的生态学稳定性机制奠定基础。结果表明,不同树龄桑树原生生物群落优势门基本一致,主要为金藻门Chrysophyta、Kinetoplastida、硅藻门Bacillariophyta、轮虫门Rotaliida、卵菌门Oomycetes和Petalomonadida,但相对丰度存在差异,在10a vs 80a、10a vs 200a和80a vs 200a中相对丰度差异显著的属分别为Paracercomonas、Petalomonas和变形虫Acanthamoeba、吻滴虫属Rhynchomonas,表明土壤原生生物群落在属水平上组成和相对丰度具有明显树龄变异。原生生物多样性受到土壤理化性质的影响,群落多样性、丰富度和均匀度与氯离子含量极显著负相关,Simpson指数与全盐量显著负相关,群落覆盖度与速效钾和碱解氮含量显著正相关。桑根际原生生物与真菌、细菌之间存在共同的环境偏好或潜在的生物相互作用。
基金Project(2016YFC0700100) supported by the National Key R&D Program of ChinaProject(JDJQ20160103) supported by Promotion of the Connotation Development Quota Project of Colleges and Universities-Outstanding Youth of Architectural University,China
文摘The standard k-ε turbulence model and discrete phase model (DPM) were used to simulate the heat and mass transfer in a liquid-desiccant evaporator driven by a heat pump using FLUENT software, and the temperature field and velocity field in the device were obtained. The performance of the liquid-desiccant evaporator was studied as the concentration of the inlet solution varied between 21% and 30% and the pipe wall temperature between 30 and 50 ℃. Results show that the humidification rate and the humidification efficiency increased with the inlet air temperature, the solution flow rate, the solution temperature, and the pipe wall temperature. The humidification rate and humidification efficiency decreased with increasing moisture content in inlet air and the concentration of inlet solution. The humidification rate increased substantially but the humidification efficiency decreased as the inlet air flow rate increased. The error between the simulations and experimental results is acceptable, meaning that our model can provide a theoretical basis for optimizing the performance of a humidifying evaporator.