Soil structure and its quality are fundamental properties because they control many processes in soils. Tillage, crop and other factors influence soil structure. Efficient protection of it needs indication of changes in soil structure. A new Normalized Stability Index proposed by Six et al. (2000) tries to evaluate these changes, which was comp...ared with some former used indices. The most common method (wet sieving) was modified to reduce the confounding effects of different particle size distribution of different soil types and method used to the investigation. Changes in soil structure caused by tillage and crop management therefore have been made quantitative and comparable. In this paper, we review the new method and Normalized Stability Index proposed by Six et al. (2000) and present the results of our investigations.
Soil structure may be improved by adding readily decomposable organic matter. The extent of amelioration depends on the chemical build-up and decomposability of the crop residues. Three different kinds of organic matters were investigated: (1) maize stem, (2) wheat straw, and (3) maize stem
& wheat straw. Comparing the aggregate stabiliz
Soil structure and changes in its quality caused by Maize stem (1), Wheat straw (2) and Maize stem & wheat straw (3) addition were assessed by three aggregate-stability indices. We observed that the NSI index formula proposed by Six et al. (2000) was nonsensitive to the changes in soil structure caused by the investigated organic matter add...ition. Furthermore it overestimates the aggregate-stability of the investigated silty sandy loam soil. Therefore we proposed a new modified NSI formula which is sensitive to the questionable treatments and that resulted in a more
realistic NSI data. The most sensitive index to differences of the investigated treatments were the Mean weight diameter (MWD) proposed by van Bavel (1953, in Kemper és Rosneau, 1986).
The environmental awareness, coming to the front in the 21st century, motivates us to supply the plant nutrient demand (in point of the plant, the environment and the human health) with natural materials.
Composting is known since the beginning of civilization. We came to know more the processes of composting as a result of last d
The reason of that we chose the more accurate cognition of compost utilization is to do more effective the site-specific nutrient supply. This increases the average yield and the quality of yield. Besides we can decrease the harmful effects, which endanger the plant, the environment, and the human body.
During the compost utilization experiment we blended the acid sandy soil with compost in 4 different volumetric proportions (5 treatments) than we set the pots randomized. The advantage of this method is that we can provide equal conditions for plants so we can measure the effect of treatments correctly. Our experimental plant was ryegrass (Lolium perenne L.), that grows rapidly, tolerates the glasshouse conditions, and indicates the effect of treatments well. After the harvest of ryegrass we measured the fresh and dry weight of harvested leaves and the total C-, N-, S-content of the dry matter and of the soil, we examined the pH and the salt concentration of soil as well.
Our aim was to study and evaluate the relations between the compost-soil proportion and the nutrient content of soil and plant. In our previous experiments we confirmed (based on variance analyses) that the compost has a beneficial effect on soil and increases the nutrient content of the soil (Szabó, 2009). But it’s important to appoint that the compound of compost is seasonally change: in winter the selective gathered municipal solid waste contains salt that were applied for non-skidding of roads, but salt has a negative effect to the plant. We proved that in our experiment the 25/75% compost/soil proportion was ideal for the plant. This content of compost effected 6 times higher green matter weight compared to the 100% sandy soil.
The sewage sludge compost is suitable to improve the colloid-poor sandy soils, which are common characteristics of poor water- and nutrientholding capacity. The general characteristics of sandy soils are the light mechanical composition, the low content of humus and mineral colloids, large pore size and a bad aggregate stability. They have a po...or nutrient supply capacity, due to its high porosity the organic matter is degraded very quickly to mineral colloids (Stefanovits et al., 1999).
By the compost application the soil is enriched mineral and organic colloids, thereby improving the soil structure. The effect of addition of compost to soil the water- and nutrient-holding capacity and porosity could be increased and the bulk density could be decreased (Martens and Frankenberger, 1992).
The aim of our experiment is to carry out physical measurements to determine the effects of compost treatment. In this study the results of the first year are presented.