title: Over 150 years of long-term fertilization alters spatial scaling of microbial biodiversity.
abstract: Spatial scaling is a critical issue in ecology, but how anthropogenic activities like fertilization affect spatial scaling is poorly understood, especially for microbial communities. Here, we determined the effects of long-term fertilization on the spatial scaling of microbial functional diversity and its relationships to plant diversity in the 150-year-old Park Grass Experiment, the oldest continuous grassland experiment in the world. Nested samples were taken from plots with contrasting inorganic fertilization regimes, and community DNAs were analyzed using the GeoChip-based functional gene array. The slopes of microbial gene-area relationships (GARs) and plant species-area relationships (SARs) were estimated in a plot receiving nitrogen (N), phosphorus (P), and potassium (K) and a control plot without fertilization. Our results indicated that long-term inorganic fertilization significantly increased both microbial GARs and plant SARs. Microbial spatial turnover rates (i.e., z values) were less than 0.1 and were significantly higher in the fertilized plot (0.0583) than in the control plot (0.0449) (P < 0.0001). The z values also varied significantly with different functional genes involved in carbon (C), N, P, and sulfur (S) cycling and with various phylogenetic groups (archaea, bacteria, and fungi). Similarly, the plant SARs increased significantly (P < 0.0001), from 0.225 in the control plot to 0.419 in the fertilized plot. Soil fertilization, plant diversity, and spatial distance had roughly equal contributions in shaping the microbial functional community structure, while soil geochemical variables contributed less. These results indicated that long-term agricultural practice could alter the spatial scaling of microbial biodiversity.
  
  
  OBJECTIVE
  Determining the spatial scaling of microbial biodiversity and its response to human activities is important but challenging in microbial ecology. Most studies to date are based on different sites that may not be truly comparable or on short-term perturbations, and hence, the results observed could represent transient responses. This study examined the spatial patterns of microbial communities in response to different fertilization regimes at the Rothamsted Research Experimental Station, which has become an invaluable resource for ecologists, environmentalists, and soil scientists. The current study is the first showing that long-term fertilization has dramatic impacts on the spatial scaling of microbial communities. By identifying the spatial patterns in response to long-term fertilization and their underlying mechanisms, this study makes fundamental contributions to predictive understanding of microbial biogeography.
authors: Yuting
authors: Y
authors: Liang
authors: Institute for Environmental Genomics and Microbiology and Plant Biology, University of Oklahoma, Norman, Oklahoma, USA.
authors: Liyou
authors: L
authors: Wu
authors: Rothamsted Research, Harpenden, Herts, United Kingdom.
authors: Ian M
authors: IM
authors: Clark
authors: Institute for Environmental Genomics and Microbiology and Plant Biology, University of Oklahoma, Norman, Oklahoma, USA.
authors: Kai
authors: K
authors: Xue
authors: State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing, China.
authors: Yunfeng
authors: Y
authors: Yang
authors: Institute for Environmental Genomics and Microbiology and Plant Biology, University of Oklahoma, Norman, Oklahoma, USA.
authors: Joy D
authors: JD
authors: Van Nostrand
authors: Institute for Environmental Genomics and Microbiology and Plant Biology, University of Oklahoma, Norman, Oklahoma, USA.
authors: Ye
authors: Y
authors: Deng
authors: Institute for Environmental Genomics and Microbiology and Plant Biology, University of Oklahoma, Norman, Oklahoma, USA.
authors: Zhili
authors: Z
authors: He
authors: Rothamsted Research, Harpenden, Herts, United Kingdom.
authors: Steve
authors: S
authors: McGrath
authors: Rothamsted Research, Harpenden, Herts, United Kingdom.
authors: Jonathan
authors: J
authors: Storkey
authors: Rothamsted Research, Harpenden, Herts, United Kingdom.
authors: Penny R
authors: PR
authors: Hirsch
authors: State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, China.
authors: Bo
authors: B
authors: Sun
authors: jzhou@ou.edu.
authors: Jizhong
authors: J
authors: Zhou
mesh_terms: D000383:Agriculture / Q000379:methods*; D001105:Archaea / Q000145:classification* / Q000235:genetics; D001419:Bacteria / Q000145:classification* / Q000235:genetics; D058448:Biota; D005308:Fertilizers / Q000706:statistics & numerical data*; D005658:Fungi / Q000145:classification* / Q000235:genetics; D046228:Microarray Analysis; D020411:Oligonucleotide Array Sequence Analysis; D010944:Plants / Q000145:classification*; D012988:Soil Microbiology
chemical_list: D005308:Fertilizers