Question

Effects of continuous cropping on soil physical and chemical properties?

Answer 1

ObjectiveThe objective of the experiment is to study the effect of Gerbera jamesonii continuous cropping on soil physical-chemical and biological characters. Method Using conventional methods, an experiment was conducted to investigate the changes of Gerbera jamesonii continuous cropping on soil physical-chemical properties , soil microbial and enzyme activities.ResultResults showed that compared with control, soil salt content was increased by 4.00%, 72.80%, 24.00% and 88.00%, respectively, under 1-7 years continuous cropping, while soil pH and bulk density began to decline. With the increasing of continuous cropping years, soil organic matter content and available N content was remarkably raised, but the soil available P and available K content was decreased. The activities of urase and sucrase increased in 1-3 years continuous cropping, while those enzyme activities decreased in 5-7 years, the soil catalase and phosphatase activity decreased with the continuous cropping year increasing, while the protease activity increased by 9.09%, 50.00%, 63.64%, 93.18%, respectively, under 1-7 years continuous cropping, compared with control. With the time of continuous cropping increasing, soil fungi number increased gradually, the number of 7 years continuous cropping increased by 192.04%, the number of bacteria decreased, but the number of other microorganisms increased in 1-3 years continuous cropping and decreased in 5-7 years. Conclusion Under continuous cropp