Effects of Long-term Located Fertilization on Soil Invertase Activity in Irrigated Desert Soils

To study the changes of invertase activity under long-term located fertilization,the soil invertase activities of irrigated desert soils for wheat/maize intercropping in 26th year long-term located fertilization were determined and analyzed.The results showed that soil invertase activity increased as the crops growing and reached the highest value in wheat milking stage to maturity stage and then decreased after wheat maturity.The changes of soil invertase activity were showed as the order of OSWNMCK under single fertilizer application,O+NM+OSW+NM+NM+SW under combined application of different two fertilizers and M+SW+O+NM+O+NM+SW+N under combined application of more than two fertilizers.Application of green manure could increase soil invertase activity.Soil invertase activity of organic fertilizer application combined with inorganic fertilizer was higher than that of organic fertilizer combined with organic fertilizer.The relationship was a positive correlation between soil invertase activity and soil available phosphorus.The relationship was a negative correlation between soil invertase activity,soil urease activity and alkaline phosphatase activity but it was a positive correlation between soil invertase activity and catalase activity.