Effect of soil-compost proportion on the abiotic and biotic parameters of soilplant system

Abstract

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 decades’ research, but numerous unexplained questions remained up to this day. The good compost is dark gray or brown, and it should not create an odor. It has aggregate structure, and it’s pH is neutral. Compost is soil-like (Fehér, 2001), nutrient-rich material, which contains valuable nutrients extracted from soil, so if we recycle this, we can decrease the chemical fertilizer and other (example: mineral energy) expenses.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.