title: [Effects of planting years of vegetable solar greenhouse on soil microbial flora and enzyme activities].
abstract: Taking the vegetable solar greenhouses having been planted for 2, 4, 6, 11, 13, 16, and 19 years as test objects, and with the open vegetable field as the control, this paper studied the variations of soil microbial flora and enzyme activities. With the increasing years of planting, the numbers of soil bacteria, actinomycetes, and total microbes in vegetable solar greenhouses decreased after an initial increase, and reached the maximum in the greenhouse of 11 years planting, with a significant increment of 54.8%, 63.7%, and 55.4%, respectively, as compared to the control. The number of soil fungi in the vegetable solar greenhouses increased steadily with increasing planting years, being about 2.2 times higher in the greenhouse of 11 years planting. Among the microbial physiological groups, the numbers of aerobic cellulose-decomposer, aerobic azotobacter, nitrite bacteria, denitrifier, and sulphur reducer showed the same variation trend as the soil bacteria's, and those in the greenhouse of 11 years planting being 1.5, 1.6, 1.9, 1.4, and 1.1 times of the control, respectively. The number of ammonifiers increased after an initial decrease, reached the minimum in the greenhouse of 13 years planting, being only 56.0% of the control. The enzyme activities of soil urease, polyphenol oxidase, sucrase, protease, cellulase, and alkaline phosphatase increased firstly and then decreased with the increasing years of planting, but soil catalase activity was relatively stable. Correlation analysis showed that the numbers of soil bacteria, actinomycetes, and total microbes were significantly positively correlated with all test soil enzyme activities, while the number of soil fungi had significant negative correlation with the activity of soil catalase.
authors.affiliation: College of Resources and Environment Sciences, Gansu Agricultural University, Lanzhou 730070, China. yangqinjcdd@163.com
authors.forename: Qin
authors.initials: Q
authors.lastname: Yang
authors.affiliation: College of Resources and Environment Sciences, Gansu Agricultural University, Lanzhou 730070, China.
authors.forename: Liang
authors.initials: L
authors.lastname: Li
mesh_terms: D000383:Agriculture / Q000379:methods*; D002374:Catalase / Q000378:metabolism; D002681:China; D017753:Ecosystem; D004780:Environment, Controlled; D012987:Soil / Q000737:chemistry; D012988:Soil Microbiology; D013997:Time Factors; D014510:Urease / Q000378:metabolism*; D014675:Vegetables / Q000254:growth & development*
chemical_list: D012987:Soil; D002374:Catalase; D014510:Urease