Effect of fertilizer and manure application on microbial numbers, biomass, and enzyme activities in volcanic ash soils

Effect of fertilizer and manure application onL-glutaminase andL-asparaginase activities in soils

“…Thus, these activities increased in response to the long-term application of chemical fertilizer and manure compared to the NF plot, particularly in the OM plot. These results correspond to our previous findings (Hasebe et al 1984;Kanazawa et al 1988), showing that the growth of microorganisms (microbial biomass) increased with the contents of available organic carbon and nitrogen, because these exocellular enzymes were produced by soil microorganisms. There was also a moderate correlation between the activities and the total carbon content, as reported by Frankenberger and Tabatabai (1991).…”

Nitrogen uptake response of vegetable crops to organic materials

“…For instance, Hayano (1983Hayano ( , 1985 and Hayano et al (1995) reported wide differences in the activity of phosphatase, phosphomonoesterase, phosphodiesterase, and ,a-glucosidase between soil areas with or without the root system hereafter referred to as "rhizosphere and non-rhizosphere soils," but the differences in the protease activity were negligible. Kanazawa et al (1988) also did not detect any variation in the protease activity between rhizosphere and non-rhizosphere soils among several crops.…”

Relationship between the amount of organic material applied and soil biomass content

“…The field soil with a high total C content (Yatsugatake, Ibaraki, and Tochigi fields) in the current study consisted of volcanic ash soil. Asaka et al (1988) and Kanazawa et al (1988) already reported that the ratio of biomass C to the total C in volcanic ash soil was lower than that in non-volcanic ash soil. Kanazawa et al (1988) stated that the low ratio of biomass C to the total C in volcanic ash soil was due to the low ratio of available organic substances to total organic matter.…”