Search
Search Results
-
The Effect of Soil Coverings on Cellulose Decomposition Activity of Sandy Soil
15-20Views:180The purpose of our experiments is to discover the effect of different soil cover matter (agroszövet and black polyethylene) on actual (under field circumstances) and potential (under laboratory circumstances) cellulose decomposition activity. In our field research, the Unger-test was used, and in laboratory research, the Petkov-Markova method was applied. In the first year of the experiment (2000) actual cellulose decomposition activity was significantly higher in covered than in the uncovered soil both in spring and autumn. The difference between the two treatments was significant only in spring. In the spring of 2001 black polyethylene showed significantly the lowest, activity, while in autumn the agroszövet (a porous black polyethylene) showed significantly the highest activity. In the autumn of 2001 the soil covered by black polyethylene gave non-significant,and the soil covered by agroszövet gave a significant higher activity value than the control. Averaging the two experimental years (2000-2001), the actual cellulose decomposition activity was significantly higher in covered soils both in spring (with 30-39%) and in autumn (with 34-69%). Moreover, in autumn a significantly higher value was detected under agroszövet than in any other treatment. The difference between the effect of treatments was not significant. In 2000, the potential cellulose decomposition activity was the highest in soil covered by agroszövet in spring, but in autumn higher activity value was detected in every covered soil than in the control. In the spring of 2001, every covered soil showed a lower, but in autumn a higher, potential cellulose decomposition rate than the control. The activity decreased significantly 27 (agroszövet) and 45 (black polyethylene) percent in spring, and increased no- significantly 8 (agroszövet) and 4 (black polyethylene) percent in autumn. During the two experimental years, we observed on average lower potential cellulose decomposition activity (15-60%) in spring and a higher one (14-43%) in autumn. Neither was significant. The dynamic of potential cellulose decomposition activity averaging 2000 and 2001 showed a slight, the actual cellulose decomposition activity an explicit non-significant upward tendency. There was a strong (r=0,189) correlation obtained between the actual and potential cellulose decomposition activity of soil, and a medium-strong (r=0,673) relationship between the soil moisture content and actual cellulose decomposition activity.
-
Effect of extreme crop year on soil moisture in maize
35-40Views:190We examined the change of the time of water balance of soil in 25 years old experiment, on chernozem soil, in different croprotation systems (mono-, bi- and triculture) in two extreme cropyear in 2007 and 2009 in maizestock.
According to our findings the values of waterdeficit of soil of maizestock were about 100 mm before the sowing time that grew because of considerable deficit of precipitation and high average temperature in months of summer. Values of waterdeficit achieved at the end of August the maximum and lessed a little bit to end of crop time. Decrease of waterstock stopped because of irrigation treatments in irrigated plots but the difference between two irrigation treatments (Ö1-Ö3) vanishedat the end of summer, waterdeficit were higher with 17 mm in monoculture in irrigated plot than value of not-irrigated plot. Considerabler precipitation in Jun effected on waterbalance of soils of three of crop-rotation systems favourable, rapid waterloss starting to april began to lessenat the end of May and started to increase from early in July. Precipitation in Jun had positiv effect on yield also. -
Changes of some soil chemical and microbiological characteristics in a long-term fertilization experiment in Hungary
253-265Views:650Agricultural management practices – directly or indirectly – influence soil properties.
Fertilization rates and crop rotation can strongly affect soil pH, soil nutrient supply and soil organic matter content due to the changes of microbial processes. The objective of this study was to compare the effects of different fertilization doses in monoculture and tri-culture of maize (monoculture: only maize grown since 1983, tri-culture: it is a three-year crop rotation system: pea – winter wheat – maize) on selected soil characteristics. The long-term fertilization experiments were set up in 1983 in Eastern Hungary. These experiments are situated west of Debrecen in Hajdúság loess region, on calcareous chernozem (according to WRB: Chernozems).
The test plant was maize (Zea mays L.). One-one pilot blocks were selected from monoculture and tri-culture of the long-term experiments. The observed soil samples were taken in the 30th year of the experiment, in 2013. The doses of NPK fertilizers increased parallel together, so the effects of N-, P- and K-fertilizers cannot be separated.
With the increasing fertilizer doses, the soil pH has decreased in both crop production systems and, in parallel, the hydrolytic acidity has significantly increased. A close negative correlation was proved between the pHH2O, pHKCl and hydrolytic acidity. An increased nutrient content in soil was recorded in every NPK treatment and the available phosphorus and nitrate content increased in higher proportion than that of potassium. Of the measured parameters of C-and N-cycles, fertilization has mostly had a positive effect on the microbial activity of soils. Besides the effects of fertilizer doses, correlation were looked for between soil microbiological properties. Evaluating the ratios among the measured parameters (organic carbon and microbial biomass carbon, OC/MBC ratio; carbon-dioxide and microbial biomass carbon; CO2/MBC proportion), the fertilization rate seems to be favoured by the increase of amounts of organic compounds