Abstrakt: |
Modern sand‐based golf course putting greens are constructed for optimum soil physical properties. However, since they are sand based and synthetically prepared, it is often perceived that they support a less numerous and diverse microbial population than comparable native soils. This field study was conducted to monitor the microbial properties of five newly constructed sand‐based rootzone mixtures planted to creeping bentgrass (Agrostis stoloniferavar. palustrisHuds. Farw.) during the first 2 yr of turfgrass establishment. Bacteria, fungi, actinomycetes, and aerobic spore forming (Bacillusspp.) populations were determined on selective media. Nitrifiers and denitrifiers were estimated by a most probable number (MPN) technique. Within the first 6 mo after seeding, bacteria exceeded 108cfu g−1dry soil, similar to levels recorded in a mature sand‐based putting green. Bacteria were most numerous followed by actinomycetes, fungi, and Bacillusspp., respectively. Temporal changes in microbial populations were observed only in year one. The nitrogen transforming populations were numerically smaller (<104cfu g−1dry soil) than total bacteria but followed a similar temporal trend. Rootzone amendments had minimal effects on microbial properties but environmental factors and an actively growing turfgrass root system may have a greater influence on microbial activity. |